JPH04110618A - Liquid level sensor - Google Patents
Liquid level sensorInfo
- Publication number
- JPH04110618A JPH04110618A JP2230312A JP23031290A JPH04110618A JP H04110618 A JPH04110618 A JP H04110618A JP 2230312 A JP2230312 A JP 2230312A JP 23031290 A JP23031290 A JP 23031290A JP H04110618 A JPH04110618 A JP H04110618A
- Authority
- JP
- Japan
- Prior art keywords
- liquid level
- liquid
- level sensor
- electrodes
- capacitance
- 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 59
- 239000000758 substrate Substances 0.000 claims abstract description 10
- 238000005259 measurement Methods 0.000 abstract description 5
- 230000000694 effects Effects 0.000 description 2
- -1 polyphenylene sulfate Polymers 0.000 description 2
- 239000004642 Polyimide Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 239000002828 fuel tank Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000010705 motor oil Substances 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 229920000139 polyethylene terephthalate Polymers 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 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】
（産業上の利用分野〕
この発明は、液体の液面レベルを測定するのに用いられ
る液面センサーに関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a liquid level sensor used to measure the level of a liquid.
液体の液面レベルを測定するものとしては、従来から、
フロートによる機械式の液面計と、電極が液体につかる
ことによる電気抵抗の変化を検出する電気式の液面計と
がある。Conventionally, methods for measuring the liquid level are:
There are mechanical liquid level gauges that use floats and electric level gauges that detect changes in electrical resistance when electrodes are immersed in liquid.
Ｃ発明が解決しようとする課題〕
ところが、機械式の液面計は、フロートの大きさや動き
やすさ等で測定精度に制限を受けるという問題の他に、
フロートを含む機械式であるため大型であるという問題
がある。Problems to be solved by the invention C] However, mechanical liquid level gauges have the problem that measurement accuracy is limited by the size and ease of movement of the float, etc.
Since it is a mechanical type that includes a float, there is a problem that it is large.
一方、従来の電気式の液面計は、ある一定の位置に一組
の電極を配置し、この位置まで液体がきたら両電極間が
導通する、あるいは抵抗値が変化するのでこれを検出す
るというものであり、つまり液体の有無を検出するだけ
のものであり、連続的な液面レベルを精密に測定するこ
とはできない。On the other hand, conventional electric liquid level gauges place a set of electrodes at a certain position, and when the liquid reaches this position, conduction occurs between the two electrodes, or the resistance value changes, which is detected. In other words, it only detects the presence or absence of liquid, and cannot accurately measure continuous liquid level.
そこでこの発明は、小型化が可能であり、しかも精密な
液面レベル測定が可能な液面センサーを提供することを
主たる目的とする。Therefore, the main object of the present invention is to provide a liquid level sensor that can be miniaturized and that can accurately measure the liquid level.
１課題を解決するための手段〕
上記目的を達成するため、この発明の液面センサーは、
絶縁基体の表面に交差指形電極を形成して成ることを特
徴とする。1. Means for Solving the Problem] In order to achieve the above object, the liquid level sensor of the present invention has the following features:
It is characterized by forming interdigital electrodes on the surface of an insulating substrate.
この液面センサーの一部分を液体につけると、液体の誘
電率や抵抗率により、その液面レベルに応じて、交差指
形電極間の静電容量や抵抗値が連続的に変化する。しか
も、交差指形電極を用いているため、その各電極指に液
面が達するごとに、上記静電容量や抵抗値は階段状に明
確に変化する。When a portion of this liquid level sensor is immersed in liquid, the capacitance and resistance value between the interdigital electrodes continuously change depending on the liquid level depending on the dielectric constant and resistivity of the liquid. Moreover, since interdigital electrodes are used, each time the liquid level reaches each electrode finger, the capacitance and resistance value change clearly in a stepwise manner.
従ってこの液面センサーの静電容量や抵抗値を測定する
ことによって精密な液面レベル測定が可能になる。Therefore, by measuring the capacitance and resistance of this liquid level sensor, precise liquid level measurement becomes possible.
［実施例〕
第１図は、この発明の一実施例に係る液面センサーを液
体につげて示す拡大正面図である。[Embodiment] FIG. 1 is an enlarged front view showing a liquid level sensor according to an embodiment of the present invention immersed in liquid.
この液面センサー２は、絶縁基体３の表面に交差指形電
極４を形成して成る。The liquid level sensor 2 includes interdigital electrodes 4 formed on the surface of an insulating base 3.
絶縁基体３としては、例えば、ポリフェニレンサルフェ
イト、ポリエチレンテレフタレート、ポリイミド等から
成るフレキシブルな樹脂フィルムや、ガラス、セラミッ
クス等からなる絶縁基板を用いることができる。As the insulating substrate 3, for example, a flexible resin film made of polyphenylene sulfate, polyethylene terephthalate, polyimide, etc., or an insulating substrate made of glass, ceramics, etc. can be used.
フレキシブルな絶縁基体３上に交差指形電極４を形成す
ることで、当該液面センサー２を例えば円筒形容器や変
形容器の内面に張り付けて使用することができる。By forming the interdigital electrodes 4 on the flexible insulating substrate 3, the liquid level sensor 2 can be used, for example, by being attached to the inner surface of a cylindrical container or a deformable container.
交差指形電極４は、インターディジタル形電極とも呼ば
れるものであり、一対のくし形電極４ａ、４ｂを隙間を
あけて噛み合わせたものである。５ａ、５１−＋はその
端子電極である。The interdigital electrode 4 is also called an interdigital electrode, and is a pair of comb-shaped electrodes 4a and 4b that are interlocked with each other with a gap between them. 5a and 51-+ are the terminal electrodes thereof.
この交差指形電極４は、例えばＡ９！、Ａｕ等の導電性
材料から成り、その電極幅は例えば数μｍ〜数ｍｍとし
、電極間隔Ｇも例えば数μｍ〜数ｍｍとし、これを適当
な長さで絶縁基体３上に形成すれば良い。This interdigital electrode 4 is, for example, A9! , made of a conductive material such as Au, the electrode width is, for example, several μm to several mm, and the electrode spacing G is, for example, several μm to several mm, and may be formed to an appropriate length on the insulating substrate 3. .
この液面センサー２の一部分を液体６につけると、液体
６の誘電率や抵抗率により、その液面レベルに応じて、
交差指形電極４間の（より具体的にはその端子電極５ａ
、５ｂ間の）静電容量や抵抗値が変化する。より具体的
には、液体６が導電性の場合は抵抗値の変化を、絶縁性
の場合は静電容量の変化を見れば良い。When a part of this liquid level sensor 2 is immersed in the liquid 6, depending on the dielectric constant and resistivity of the liquid 6, depending on the liquid level,
Between the interdigital electrodes 4 (more specifically, the terminal electrodes 5a)
, 5b) and the resistance value change. More specifically, if the liquid 6 is conductive, the change in resistance may be observed, and if the liquid 6 is insulating, the change in capacitance may be observed.
しかも、交差指形電極４を用いているため、その各電極
指４Ｃに液体６の液面が達するごとに、上記静電容量や
抵抗値は階段状に明確に変化する。Moreover, since the interdigital electrodes 4 are used, the capacitance and resistance value change clearly in a stepwise manner each time the surface of the liquid 6 reaches each electrode finger 4C.
その−例を第２図に示す。An example is shown in FIG.
従ってこの液面センサー２を用いてその静電容量や抵抗
値を別の測定回路で測定することによって、液体６の精
密な液面レベル測定が可能になる。Therefore, by using this liquid level sensor 2 and measuring its capacitance and resistance value with a separate measuring circuit, it becomes possible to accurately measure the liquid level of the liquid 6.
しかもこの液面センサー２は、絶縁基体３の表面に交差
指形電極４を形成して成るものであるから、非常に小型
にできる。Moreover, since this liquid level sensor 2 is formed by forming interdigital electrodes 4 on the surface of an insulating substrate 3, it can be made very small.
ちなみに、交差指形電極４の代わりに、単なる２本の平
行電極を用いた場合は、静電容量や抵抗値は液面レベル
に応じて非常に緩やかにしが変化しないため、液面レベ
ルの精密な測定は困難である。これに対してこの実施例
のように交差指形電極４を用いると、少な（ともその電
極間隔Ｇふんの分解能で精密に液面レベル測定が可能で
ある。By the way, when simply two parallel electrodes are used instead of the interdigital electrode 4, the capacitance and resistance value do not change very gradually depending on the liquid level, so it is difficult to accurately determine the liquid level. It is difficult to make accurate measurements. On the other hand, if interdigital electrodes 4 are used as in this embodiment, the liquid level can be precisely measured with a small resolution (or at least the electrode spacing G).
換言すれば、高分解能を得たければそれに応じて交差指
形電極４の電極間隔Ｇを小さくすれば良い。In other words, if high resolution is desired, the electrode spacing G of the interdigital electrodes 4 may be reduced accordingly.
このような液面センサー２は、例えば、自動車等の燃料
タンク、エンジンオイル等の残量センサーや、オイルマ
ノメータの指示値の自動読み取り等にも使用することが
できる。Such a liquid level sensor 2 can be used, for example, as a sensor for the remaining amount of fuel tank or engine oil in an automobile, etc., or for automatically reading the indicated value of an oil manometer.
以上のようにこの発明の液面センサーによれば、小型化
が可能であり、しがも精密な液面レベル測定が可能にな
る。As described above, according to the liquid level sensor of the present invention, it is possible to downsize the liquid level, and it is also possible to precisely measure the liquid level.
第１図は、この発明の一実施例に係る液面センサーを液
体につけて示す拡大正面図である。第２図は、第１図の
液面センサーにおける液面レベルと静電容量との関係の
概略を示すグラフである。
２、・・実施例に係る液面センサー ３・・・絶縁基体
、４・・・交差指形電極、６０２．液体。FIG. 1 is an enlarged front view showing a liquid level sensor according to an embodiment of the present invention immersed in liquid. FIG. 2 is a graph schematically showing the relationship between the liquid level and capacitance in the liquid level sensor of FIG. 1. 2. Liquid level sensor according to the example 3. Insulating substrate, 4. Interdigital electrode, 602. liquid.
Claims (1)
とを特徴とする液面センサー。(1) A liquid level sensor characterized by forming interdigital electrodes on the surface of an insulating substrate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2230312A JPH04110618A (en) | 1990-08-30 | 1990-08-30 | Liquid level sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2230312A JPH04110618A (en) | 1990-08-30 | 1990-08-30 | Liquid level sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04110618A true JPH04110618A (en) | 1992-04-13 |
Family
ID=16905863
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2230312A Pending JPH04110618A (en) | 1990-08-30 | 1990-08-30 | Liquid level sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04110618A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11108735A (en) * | 1997-10-03 | 1999-04-23 | Nitta Ind Corp | Water level sensor |
| WO2002084228A1 (en) * | 2001-04-11 | 2002-10-24 | Robert Bosch Gmbh | Capacitive sensor element and method for producing a capacitive sensor element |
| JP2011214904A (en) * | 2010-03-31 | 2011-10-27 | Seiren Co Ltd | Liquid level detector and inkjet recording device including the same |
| CN102268807A (en) * | 2010-06-01 | 2011-12-07 | 三星电子株式会社 | Dryer and control method of same |
| KR101148630B1 (en) * | 2010-04-30 | 2012-05-24 | 안동대학교 산학협력단 | Structure of water level sensor |
| JP2014021073A (en) * | 2012-07-23 | 2014-02-03 | Aisan Ind Co Ltd | Liquid sensor |
| EP4312003A1 (en) * | 2022-07-28 | 2024-01-31 | ASM IP Holding B.V. | Capacitive sensor system for precursor level measurement and method therefor |
-
1990
- 1990-08-30 JP JP2230312A patent/JPH04110618A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11108735A (en) * | 1997-10-03 | 1999-04-23 | Nitta Ind Corp | Water level sensor |
| WO2002084228A1 (en) * | 2001-04-11 | 2002-10-24 | Robert Bosch Gmbh | Capacitive sensor element and method for producing a capacitive sensor element |
| JP2011214904A (en) * | 2010-03-31 | 2011-10-27 | Seiren Co Ltd | Liquid level detector and inkjet recording device including the same |
| KR101148630B1 (en) * | 2010-04-30 | 2012-05-24 | 안동대학교 산학협력단 | Structure of water level sensor |
| CN102268807A (en) * | 2010-06-01 | 2011-12-07 | 三星电子株式会社 | Dryer and control method of same |
| JP2014021073A (en) * | 2012-07-23 | 2014-02-03 | Aisan Ind Co Ltd | Liquid sensor |
| EP4312003A1 (en) * | 2022-07-28 | 2024-01-31 | ASM IP Holding B.V. | Capacitive sensor system for precursor level measurement and method therefor |
| US12656165B2 (en) | 2022-07-28 | 2026-06-16 | Asm Ip Holding B.V. | Capacitive sensor system for precursor level measurement and method therefor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4641434A (en) | Inclination measuring device | |
| US4429343A (en) | Humidity sensing element | |
| KR950014819B1 (en) | Electronic inclinometer | |
| US6222376B1 (en) | Capacitive moisture detector and method of making the same | |
| US4564882A (en) | Humidity sensing element | |
| US20080231290A1 (en) | Capacitive Position Sensor | |
| US4763534A (en) | Pressure sensing device | |
| JPH0512661B2 (en) | ||
| US7550979B2 (en) | System and method for measuring conductivity of fluid | |
| JPH0337501A (en) | Electrostatic capacitance type detecting apparatus | |
| GB2055477A (en) | Electrostatic type fuel measuring device | |
| JPS6263852A (en) | Temperature compensated capacitive humidity sensor | |
| JP7071723B2 (en) | Circuit for measuring complex permittivity, device for measuring complex permittivity, and method for measuring complex permittivity | |
| JPH11108735A (en) | Water level sensor | |
| CN102980630A (en) | Intelligent digital capacitive liquid level sensor | |
| US5479716A (en) | Capacitive based gravity sensor | |
| JP2020003356A (en) | Sensor device | |
| JP3165484B2 (en) | Liquid level sensor | |
| JPS6379016A (en) | Liquid level measuring apparatus | |
| EP0430651B1 (en) | Level sensor | |
| JP2003057093A (en) | Electrode for liquid level detector | |
| JPH03125917A (en) | Capacitance type linear encoder | |
| GB2064130A (en) | Electromagnetic Channel Flowmeter | |
| KR102260386B1 (en) | Sensing device | |
| JP4052716B2 (en) | Pressure detecting element and pressure sensor |