JPH04118524A - Liquid level meter - Google Patents
Liquid level meterInfo
- Publication number
- JPH04118524A JPH04118524A JP24044490A JP24044490A JPH04118524A JP H04118524 A JPH04118524 A JP H04118524A JP 24044490 A JP24044490 A JP 24044490A JP 24044490 A JP24044490 A JP 24044490A JP H04118524 A JPH04118524 A JP H04118524A
- Authority
- JP
- Japan
- Prior art keywords
- liquid level
- electrode
- electrodes
- resistance
- conductivity
- 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.)
- Pending
Links
- 239000007788 liquid Substances 0.000 title claims abstract description 56
- 238000000034 method Methods 0.000 description 6
- 230000005855 radiation Effects 0.000 description 3
- 238000001514 detection method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 239000006060 molten glass Substances 0.000 description 1
Landscapes
- Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
Abstract
Description
【発明の詳細な説明】
（イ）産業上の利用分野
この発明は、液位計、特に被検出物の導電率の変化の影
響を受けずに液位を計測し得る液位計に関する。DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a liquid level meter, and particularly to a liquid level meter that can measure liquid level without being affected by changes in the conductivity of a detected object.
（ロ）従来の技術
従来、例えばルツボ内の溶融ガラス等の液位を検出する
のに、■対になった電極に電圧を印加し、その抵抗から
逆算して液位を算出する。■対になった電極の一方をル
ツボに接続し、他方の電極を上下させ、電極が導通ずる
位置から液位を検出する。■放射線源からの放射線の減
衰率から液位を検出する。■レーザ光等の反射を利用し
て液位を定める。等の方法が採用されている。(b) Prior Art Conventionally, in order to detect the liquid level of molten glass or the like in a crucible, for example, (2) a voltage is applied to a pair of electrodes, and the liquid level is calculated by back calculation from the resistance. (1) Connect one of the paired electrodes to the crucible, move the other electrode up and down, and detect the liquid level from the position where the electrode becomes conductive. ■Detect the liquid level from the attenuation rate of radiation from the radiation source. ■Using reflection of laser light, etc. to determine the liquid level. The following methods have been adopted.
（ハ）発明が解決しようとする課題
上記した従来の液位の計測技術のうち、■、■の放射線
源、あるいはレーザ光を使用する方法は、装置が大がか
りとなり、かつ高価になるという問題があるし、■の方
法は簡便であるが、レスポンスが悪く、かつ狭い場所で
の使用が困難であるという問題があるし、さらに■の方
法は最も簡便ではあるが、液位を検出したい被検出液体
の導電率が温度等の影響で変化する場合は、その変化が
そのまま液位の誤差となって出力されるという問題があ
った。(c) Problems to be Solved by the Invention Among the conventional liquid level measurement techniques described above, methods using a radiation source or a laser beam (2) and (3) have the problem that the equipment becomes large-scale and expensive. Although method (■) is simple, it has problems such as poor response and is difficult to use in narrow spaces.Furthermore, method (■) is the simplest, but it is difficult to use when the liquid level is to be detected. When the conductivity of the liquid changes due to the influence of temperature or the like, there is a problem in that the change is directly output as an error in the liquid level.
この発明は、上記問題点に着目してなされたものであっ
て、簡易な構成で被検出液の導電率の変化の影響を受け
ない液位計を提供することを目的としている。The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a liquid level meter that has a simple configuration and is not affected by changes in the conductivity of the liquid to be detected.
（ニ）課題を解決するための手段及び作用この発明の液
位計は、第１の対の電極と、この第１の対の電極とは液
面よりの長さが相違する第２の対の電極と、これら第１
の対及び第２の対の電極の各月の電極間抵抗を測定する
手段と、測定された各月の電極間抵抗に基づいて液位を
計算する手段とを備えている。(d) Means and operation for solving the problems The liquid level meter of the present invention includes a first pair of electrodes and a second pair of electrodes having different lengths from the liquid surface. electrodes and these first electrodes.
means for measuring the inter-electrode resistance for each month of the pair of electrodes and the second pair of electrodes, and means for calculating the liquid level based on the measured inter-electrode resistance for each month.
一対の電極を用いて液位を検出しようとすれば、算出式
の中に導電率と液位の２つの未知数を含むが、この発明
の液位計では、２対の電極で、それぞれの電極間の抵抗
を測定し、得られる２式より導電率を消去できるので、
導電率の変化の影響を受けることなく、純粋に液位の検
出を行うことができる。If you try to detect the liquid level using a pair of electrodes, the calculation formula will include two unknowns, conductivity and liquid level, but in the liquid level meter of this invention, two pairs of electrodes are used, each electrode is Since we can measure the resistance between and eliminate the conductivity from the two equations obtained,
Pure liquid level detection can be performed without being affected by changes in conductivity.
（ホ）実施例
以下、実施例により、この発明をさらに詳細に説明する
。(E) Examples The present invention will be explained in more detail with reference to Examples below.
図面は、この発明の一実施例を示す液位計の構成図であ
る。同図において、被検出液１に、２対の電極棒２．３
と４．５が挿入される。電極棒２と３は長さが同じで、
距離ｄをおいて配置されている。電極棒４と５も長さが
同じで距離ｄをおいて配置されている。電極棒２．３は
電極棒４．５よりもｌだけ長く設定されている。電圧■
。の電池６の（−）側が電極棒３と５に接続されている
。The drawing is a configuration diagram of a liquid level gauge showing an embodiment of the present invention. In the figure, two pairs of electrode rods 2 and 3 are connected to the liquid to be detected 1.
and 4.5 are inserted. Electrode rods 2 and 3 have the same length,
They are placed at a distance d. The electrode rods 4 and 5 also have the same length and are placed at a distance d. The electrode rod 2.3 is set to be longer than the electrode rod 4.5 by l. Voltage■
. The (-) side of the battery 6 is connected to the electrode rods 3 and 5.
電池６の（＋）側が抵抗７を介して電極棒２に接続され
るとともに、アンプ９の入力の一端に接続され、また電
池６の（＋）側は抵抗８を介して電極棒４に接続される
とともにアンプ１０の入力の一端に接続されている。電
池６の（＋）側は、さらにアンプ９．１０の各入力の他
端にも接続されている。アンプ９は抵抗７の両端電圧■
１を増幅し、アンプ１０は抵抗８０両端電圧Ｖ！を増幅
し、出力する。アンプ９．１０の出力電圧は、それぞれ
Ａ／Ｄ変換器１１．１２でデジタル信号に変換され、Ｃ
ＰＵ１３に取り込まれるようになっている。The (+) side of the battery 6 is connected to the electrode bar 2 via a resistor 7 and also connected to one end of the input of an amplifier 9, and the (+) side of the battery 6 is connected to the electrode bar 4 via a resistor 8. and is connected to one end of the input of the amplifier 10. The (+) side of the battery 6 is further connected to the other end of each input of the amplifier 9.10. Amplifier 9 is the voltage across resistor 7■
1, and the amplifier 10 amplifies the voltage V! across the resistor 80. Amplify and output. The output voltages of amplifiers 9 and 10 are respectively converted into digital signals by A/D converters 11 and 12, and C
It is designed to be taken into the PU13.
次に、以上のように構成される液位計により、液位を測
定する場合について説明する。Next, a case will be described in which the liquid level is measured using the liquid level meter configured as described above.
なお、被検出液１の液面から、電極棒２．３の下先端ま
での深さをＬｌ、電極棒４．５の下先端までの深さをＬ
２とし、液位としてＬ２を求めるものとする。Note that the depth from the liquid level of the liquid to be detected 1 to the lower tip of the electrode rod 2.3 is Ll, and the depth to the lower tip of the electrode rod 4.5 is L.
2, and L2 is determined as the liquid level.
測定時に電池６より抵抗７と抵抗８を介して、電極棒２
、被検出液１、電極棒３と、電極棒４、被検出液１、電
極棒５にそれぞれ電流が流れる。During measurement, the electrode rod 2 is connected to the battery 6 through the resistor 7 and the resistor 8.
, current flows through the liquid to be detected 1, the electrode rod 3, the electrode rod 4, the liquid to be detected 1, and the electrode rod 5, respectively.
したがって、抵抗７．８の抵抗値をＲ，□、Ｒ２２、電
極棒２．３間の被検出液１の抵抗値をＲＩ １、電極棒
４．５間の被検出液の抵抗値をＲ２１とすると。Therefore, the resistance value of the resistor 7.8 is R, □, R22, the resistance value of the liquid to be detected between the electrode rods 2.3 is RI1, and the resistance value of the liquid to be detected between the electrode rods 4.5 is R21. Then.
で、被検出液ｌの電極部での抵抗値Ｒ１１、ＲＺＩを算
出できる。この算出はＣＰＵ１３で実行される。Then, the resistance values R11 and RZI of the liquid to be detected 1 at the electrode portion can be calculated. This calculation is executed by the CPU 13.
一方、対向棒状電極の場合、その間の抵抗Ｒ１８、Ｒ，
□は、
で与えられる。ここで、ａは電極半径、には、被検出液
の導電率である。On the other hand, in the case of opposing rod-shaped electrodes, the resistances R18, R,
□ is given by . Here, a is the electrode radius, and a is the conductivity of the liquid to be detected.
（１）式で算出した抵抗値Ｒ０、Ｒ２１を（２）式に入
れ、導電率にを消去し、かつり、＝Ｌ、＋ｆｆｉである
ことを考慮すると、液位Ｌ２は次式
％式％
この（３）式によって求められる液位Ｌｔは、導電率に
にかかわらない値である。Inserting the resistance values R0 and R21 calculated by the formula (1) into the formula (2), deleting from the conductivity, and considering that =L, +ffi, the liquid level L2 can be calculated using the following formula % formula % The liquid level Lt determined by this equation (3) is a value that is independent of electrical conductivity.
（３）式をＣＰＵ１３で算出することにより、温度等の
変化による導電率の変化の影響を受けることなく、液位
を検出できる。By calculating equation (3) by the CPU 13, the liquid level can be detected without being affected by changes in conductivity due to changes in temperature or the like.
２対の電極２．３と４．５の長さの差ｌは、導電率の高
さ、測定しようとする液位に応じて決定する。The difference l between the lengths of the two pairs of electrodes 2.3 and 4.5 is determined depending on the level of conductivity and the liquid level to be measured.
また、２対電極は、必ずしも棒状電極に限るものではな
く、液位と抵抗との関係が予め既知なら、他の形状のも
のであってもよい。Further, the two pair electrodes are not necessarily limited to rod-shaped electrodes, and may have other shapes as long as the relationship between the liquid level and the resistance is known in advance.
また、上記（１）、（３）弐等の演算をＣＰＵで行って
いるが、これに限らず、本発明では専用の演算回路を用
いてもよい。Further, although the above calculations (1), (3), etc. are performed by the CPU, the invention is not limited to this, and a dedicated calculation circuit may be used in the present invention.
また、抵抗測定方法も上記実施例の方法に限られるもの
ではない。Further, the resistance measuring method is not limited to the method of the above embodiment.
また、上記実施例では、２対の電極は、それぞれ個別の
電極棒４本を使用しているが、１本を兼用して、３木の
電極棒で２対の電極を構成するものであってもよい。Furthermore, in the above embodiment, the two pairs of electrodes each use four individual electrode rods, but one electrode can also be used to form two pairs of electrodes using three wooden electrode rods. You can.
（へ）発明の効果
この発明によれば、２対の電極を備え、各月の電極間の
抵抗値を測定し、この各月の電極間抵抗値に基づいて、
導電率を含まない式により、液位を計算するものである
から、比較的簡単な構成で導電率の変化にかかわらず、
精度の良い液位検出が可能である。(F) Effects of the Invention According to this invention, two pairs of electrodes are provided, the resistance value between the electrodes is measured for each month, and based on the resistance value between the electrodes for each month,
Since the liquid level is calculated using a formula that does not include conductivity, it has a relatively simple configuration and can be used regardless of changes in conductivity.
Accurate liquid level detection is possible.
図面はこの発明の一実施例を示す液位計の構成図である
。
１：被検出液、 ２・３・４・５：電極棒、６：電池
、 ７・８：抵抗、
：アンプ、
■
： Ａ／Ｄ変換器、
１３：ｃＰＵ。The drawing is a configuration diagram of a liquid level gauge showing an embodiment of the present invention. 1: Liquid to be detected, 2, 3, 4, 5: Electrode rod, 6: Battery, 7, 8: Resistor, : Amplifier, ■: A/D converter, 13: cPU.
Claims (1)
よりの長さが相違する第２の対の電極と、これら第１の
対及び第２の対の電極の各対の電極間抵抗を測定する手
段と、測定された各対の電極間抵抗に基づいて液位を計
算する手段とを備えたことを特徴とする液位計。(1) A first pair of electrodes, a second pair of electrodes that have different lengths from the liquid surface, and a second pair of electrodes that have different lengths from the liquid surface; A liquid level meter comprising: means for measuring the inter-electrode resistance of each pair; and means for calculating the liquid level based on the measured inter-electrode resistance of each pair.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24044490A JPH04118524A (en) | 1990-09-10 | 1990-09-10 | Liquid level meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24044490A JPH04118524A (en) | 1990-09-10 | 1990-09-10 | Liquid level meter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04118524A true JPH04118524A (en) | 1992-04-20 |
Family
ID=17059588
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24044490A Pending JPH04118524A (en) | 1990-09-10 | 1990-09-10 | Liquid level meter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04118524A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003056871A (en) * | 2001-08-10 | 2003-02-26 | Sanyo Electric Co Ltd | Humidifier |
| US7137686B2 (en) | 1997-07-15 | 2006-11-21 | Silverbrook Research Pty Ltd | Inkjet printhead having inkjet nozzle arrangements incorporating lever mechanisms |
-
1990
- 1990-09-10 JP JP24044490A patent/JPH04118524A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7137686B2 (en) | 1997-07-15 | 2006-11-21 | Silverbrook Research Pty Ltd | Inkjet printhead having inkjet nozzle arrangements incorporating lever mechanisms |
| JP2003056871A (en) * | 2001-08-10 | 2003-02-26 | Sanyo Electric Co Ltd | Humidifier |
| JP4683789B2 (en) * | 2001-08-10 | 2011-05-18 | 三洋電機株式会社 | Humidifier |
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