JPH063307A - Humidity sensor - Google Patents
Humidity sensorInfo
- Publication number
- JPH063307A JPH063307A JP4157091A JP15709192A JPH063307A JP H063307 A JPH063307 A JP H063307A JP 4157091 A JP4157091 A JP 4157091A JP 15709192 A JP15709192 A JP 15709192A JP H063307 A JPH063307 A JP H063307A
- Authority
- JP
- Japan
- Prior art keywords
- humidity
- changes
- sensor
- resistance
- conductive paper
- 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
Landscapes
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は、主に恒温恒湿槽内の
湿度を検出して槽内の湿度を測定又は一定に保つための
監視をしたり制御を行うための湿度センサに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a humidity sensor for detecting humidity in a constant temperature and humidity chamber, and for monitoring or controlling for measuring or keeping the humidity in the chamber constant.
【０００２】[0002]
【従来の技術】空気中の湿度を測定する方法には、例え
ば乾湿計、毛髪計、露点計あるいは、塩化リチューム皮
膜などの電気抵抗の湿度による変化を利用した電気湿度
計など色々ある。2. Description of the Related Art There are various methods for measuring the humidity in the air, such as a psychrometer, a hair meter, a dew point meter, and an electric hygrometer utilizing a change in electric resistance of a lithium chloride film due to humidity.
【０００３】[0003]
【発明が解決しようとする課題】しかし、前述の恒温恒
湿槽の湿度を連続して測定又は監視するときの湿度計と
しては乾湿計や毛髪計あるいは露点計は適切ではなく電
気湿度計が適しているが、一般に恒温恒湿槽で一定制御
される温度は気温に比べて高温であることが多く、従来
の電気湿度計では精度や価格の点で適切なものがないと
いう問題がある。However, as a hygrometer for continuously measuring or monitoring the humidity of the above-mentioned constant temperature and humidity chamber, a psychrometer, a hair meter, or a dew point meter is not suitable, but an electric hygrometer is suitable. However, in general, the temperature that is constantly controlled in the constant temperature and humidity chamber is often higher than the temperature, and there is a problem that there is no appropriate electric hygrometer in terms of accuracy and price.
【０００４】この発明の目的は、このような問題を解決
し、恒温恒湿槽の湿度を連続して測定又は監視するとき
の湿度計として高精度でしかも安価な湿度センサを提供
することにある。An object of the present invention is to solve such a problem and to provide a highly accurate and inexpensive humidity sensor as a hygrometer when continuously measuring or monitoring the humidity of a constant temperature and constant humidity chamber. .
【０００５】[0005]
【課題を解決するための手段】上記課題を解決するため
に、この発明によれば、絶縁性繊維に所定の割合のカー
ボン繊維を混合してなる導電紙の所定の形状寸法の抵抗
値を測定信号としてなるものとし、また、絶縁性繊維が
全芳香族ポリアミド繊維であり、導電紙がこの全芳香族
ポリアミド繊維とカーボン繊維との混合繊維を湿式抄紙
により製作してなるものとする。In order to solve the above problems, according to the present invention, the resistance value of a predetermined shape and size of a conductive paper obtained by mixing a predetermined ratio of carbon fibers with insulating fibers is measured. The insulating fiber is a wholly aromatic polyamide fiber, and the conductive paper is a mixed fiber of the wholly aromatic polyamide fiber and the carbon fiber produced by wet papermaking.
【０００６】[0006]
【作用】この発明の構成において、絶縁性繊維に所定の
割合のカーボン繊維を混合して製作された導電紙の所定
の形状寸法の抵抗値を測定信号とすると、湿度が変化す
ると絶縁性繊維の膨張の程度が変化し、これによってカ
ーボン繊維同士の接触抵抗が変化することによって導電
繊維の面積抵抗が変化するのでこの抵抗を測定信号にす
れば湿度センサとなる。また、絶縁性繊維として全芳香
族ポリアミド繊維を採用し、導電紙としてこの全芳香族
ポリアミド繊維とカーボン繊維との混合繊維を湿式抄紙
により製作したものを採用すると、この導電紙の相対湿
度−面積抵抗特性は相対湿度が５０〜９５％の範囲で両
対数目盛りで直線になる特性を持ち、しかも、抵抗値は
相対湿度の約１０乗に比例した変化をするので精度の良
い湿度センサとなる。In the structure of the present invention, when the resistance value of the conductive paper produced by mixing the insulating fiber with a predetermined ratio of the carbon fiber is the measurement signal, the insulating fiber of the insulating fiber changes when the humidity changes. The degree of expansion changes, which changes the contact resistance between the carbon fibers, which changes the area resistance of the conductive fibers. Therefore, if this resistance is used as a measurement signal, a humidity sensor is obtained. Further, when a wholly aromatic polyamide fiber is adopted as the insulating fiber and a conductive fiber made of a mixed fiber of the wholly aromatic polyamide fiber and the carbon fiber is manufactured by wet papermaking, the relative humidity-area of the conductive paper is The resistance characteristic has a characteristic of being linear on a logarithmic scale in the relative humidity range of 50 to 95%, and the resistance value changes in proportion to about the tenth power of the relative humidity, so that the humidity sensor has high accuracy.
【０００７】[0007]
【実施例】以下この発明を実施例に基づいて説明する。
図１はこの発明の実施例としての湿度センサを用いた湿
度監視装置の概念図である。この図において、鎖線は恒
温恒湿槽８の内外の区別を示してあり、容器１は恒温恒
湿槽８の内部、抵抗測定器５及び記録計６は外部に設け
られてあり内部と外部とは恒温恒湿槽８を貫通する図示
しない貫通孔を通る測定リード４によって接続されてい
る。EXAMPLES The present invention will be described below based on examples.
FIG. 1 is a conceptual diagram of a humidity monitoring device using a humidity sensor as an embodiment of the present invention. In this figure, the chain line indicates the inside and outside of the constant temperature and humidity chamber 8, the container 1 is provided inside the constant temperature and humidity chamber 8, and the resistance measuring device 5 and the recorder 6 are provided outside and inside and outside. Are connected by a measurement lead 4 passing through a through hole (not shown) which penetrates the constant temperature and humidity chamber 8.
【０００８】容器１の中には長方形状の導電紙２１とそ
の両端に導電塗料を塗布して形成した電極２２からなる
湿度センサ２が設けられていてこの電極３に２本の測定
リード４がそれぞれ接続されて抵抗測定器５から電圧Ｖ
が印加される。導電紙２１の電流の流れる方向の寸法、
幅寸法及びその面積抵抗率とから決まる電極３間の抵抗
Ｒに応じた電流Ｉが電極３を通って流れるので、抵抗Ｒ
は電圧Ｖを電流Ｉで除算することによって求められる。
抵抗検出器５で求められた抵抗Ｒの値は記録計６で記
録、表示される。監視者はこの記録計６の表示を観察す
ることによって湿度管理が正常に行われていることを確
認し、また湿度が高くなり過ぎたり低くなり過ぎたりし
たときには適切な処置をとる。Inside the container 1, there is provided a humidity sensor 2 which is composed of a rectangular conductive paper 21 and electrodes 22 formed by applying conductive paint to both ends thereof, and two measuring leads 4 are attached to the electrode 3. The voltage V from the resistance measuring device 5 is connected respectively.
Is applied. The size of the conductive paper 21 in the direction of current flow,
Since the current I corresponding to the resistance R between the electrodes 3 which is determined by the width dimension and its area resistivity flows through the electrodes 3, the resistance R
Is determined by dividing the voltage V by the current I.
The value of the resistance R obtained by the resistance detector 5 is recorded and displayed by the recorder 6. The observer confirms that the humidity control is normally performed by observing the display of the recorder 6, and takes appropriate action when the humidity becomes too high or too low.
【０００９】湿度センサ２を容器１に収納してあるの
は、湿度センサ２の保護のためであり、ファン７を設け
ているのは容器１内が恒温恒湿槽８の雰囲気に速やかに
追従するためであり、これらを省略することも可能であ
る。容器１を金網にすればファン７を使用しなくても容
器１内が恒温恒湿槽８内の雰囲気に速やかに対応するこ
とができるのでこのような構成を採用することもでき
る。The reason why the humidity sensor 2 is housed in the container 1 is to protect the humidity sensor 2, and the fan 7 is provided so that the inside of the container 1 quickly follows the atmosphere of the constant temperature and humidity chamber 8. This is because it is possible to omit them. If the container 1 is a wire mesh, the inside of the container 1 can quickly respond to the atmosphere in the constant temperature and humidity chamber 8 without using the fan 7, and thus such a configuration can be adopted.
【００１０】導電紙２は全芳香族ポリアミド繊維とカー
ボン繊維とを一定の割合で配合し、湿式抄紙によって製
作されたもので、全芳香族ポリアミド繊維の湿度差によ
る膨張の差がカーボン繊維の接触抵抗の差となって現れ
る。図２は導電紙２の２０°における面積抵抗率Ｒ−相
対湿度Ｈの特性を示すグラフである。この図における導
電紙２は全芳香族ポリアミド繊維とカーボン繊維とを５
０：１の重量比で混合し、厚さ０．１mm、密度０．７５
ｇ／cm3 に仕上げたものである（（株）巴川製紙所製
APC-100 ）。The conductive paper 2 is made by wet papermaking by mixing the wholly aromatic polyamide fiber and the carbon fiber in a fixed ratio, and the difference in expansion due to the humidity difference of the wholly aromatic polyamide fiber causes the contact of the carbon fiber. It appears as a difference in resistance. FIG. 2 is a graph showing the characteristics of the area resistivity R-relative humidity H at 20 ° of the conductive paper 2. The conductive paper 2 in this figure is composed of a wholly aromatic polyamide fiber and a carbon fiber.
Mixing in a weight ratio of 0: 1, thickness 0.1mm, density 0.75
one in which finished in g / cm 3 ((Ltd.) Tomoegawa made
APC-100).
【００１１】この図において、横軸は相対湿度Ｈ
（％）、縦軸は面積抵抗率Ｒ（Ω／□）であり、両対数
目盛りである。この図から明らかなように、相対湿度Ｈ
が５０〜９５％の範囲では特性は図上で直線になってい
る。したがって、この範囲では、ＲとＨとは次式で表さ
れる関係にある。 Ｒ＝ｋＨn ‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥（１） ここで、 ｋ；比例係数 ｎ；巾乗係数 ちなみに、この図の特性では、ｋ＝６．２５×１
０-14 ，ｎ＝１０．８であり、ｎの値が１よりもはるか
に大きいことから相対湿度が僅か変化しても面積抵抗率
抵抗Ｒは大きく変化するのでこの導電紙を使用した湿度
センサ２は検出の感度が非常に良いものとなる。In this figure, the horizontal axis represents the relative humidity H.
(%), The vertical axis is the sheet resistivity R (Ω / □), which is a logarithmic scale. As is clear from this figure, the relative humidity H
In the range of 50 to 95%, the characteristics are linear in the figure. Therefore, in this range, R and H have a relationship represented by the following equation. R = kh n ‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ (1) Where, k: proportional coefficient n; power factor coefficient In the characteristic of, k = 6.25 × 1
0 -14 , n = 10.8, and since the value of n is much larger than 1, the area resistivity resistance R changes greatly even if the relative humidity changes slightly. Therefore, the humidity sensor using this conductive paper No. 2 has very good detection sensitivity.
【００１２】この図は前述のように温度が２０°Ｃにお
けるものであるが、実測によると５０°Ｃの場合は図２
のグラフに対して抵抗率Ｒが約１／２桁小さくなる。し
かし、特性グラフの傾斜は変化しない。すなわち、
（１）式の係数ｋが温度の上昇に伴って小さくなるが巾
乗係数ｎは変化しないという特徴がある。しかし、図１
のように、導電紙２による湿度センサが恒温恒湿槽８に
使用される場合には、温度が一定に保たれるので温度補
正が不要である。また、前述のように５０°Ｃの高温で
も必要とする特性を持っていることを確認しているの
で、導電紙２１を使用した湿度センサ２は５０°Ｃの高
温でも使用可能である。As shown in the figure, the temperature is at 20 ° C. as described above.
The resistivity R is about 1/2 digit smaller than that of the graph. However, the slope of the characteristic graph does not change. That is,
The coefficient k in the equation (1) decreases as the temperature rises, but the power factor n does not change. However,
As described above, when the humidity sensor based on the conductive paper 2 is used in the constant temperature and constant humidity tank 8, the temperature is kept constant, so that the temperature correction is unnecessary. Further, as described above, it has been confirmed that the humidity sensor 2 using the conductive paper 21 can be used even at a high temperature of 50 ° C. because it has been confirmed that the humidity sensor 2 has the required characteristics even at a high temperature of 50 ° C.
【００１３】なお、湿度センサ２の導電紙２１や電極２
２としての導電塗料の塗布の形状は特に図１に示すよう
な形状にこだわるものではない。また、電極２２として
導電塗料の塗布によることにこだわるものでもない。こ
の発明の目的に反しない範囲でどのような湿度センサ２
の形状、電極２２の材料を選択することができる。更
に、導電紙２１として前述のような材料と製作方法にこ
だわるものではなく、一般に絶縁性の繊維と導電性を持
つカーボン繊維との混合繊維を紙にしたものであれば、
湿度の変化に応じた繊維の膨張、これに伴うカーボン繊
維の接触抵抗に変化による導電紙の面積抵抗の変化が生
じこの面積抵抗Ｒと相対湿度Ｈとの間に一義的な関係が
得られるものなので、いずれも湿度センサとして使用す
ることが原理的に可能である。ただ、前述の構成、製作
方法による導電紙に比べてＲ−Ｈ特性の安定性、直線性
などにおいて優れていることから、現状では最適なもの
と言える。なお、この導電紙は大容量回転機の電機子巻
線の巻線端部の電界緩和のために巻線導体に巻回して使
用される市販品である。湿度センサとして使用するその
量は僅かなので湿度センサとしては安価なものになる。The conductive paper 21 and the electrodes 2 of the humidity sensor 2
The shape of application of the conductive paint as 2 is not particularly limited to the shape shown in FIG. Further, the electrode 22 is not limited to the application of conductive paint. What kind of humidity sensor 2 does not deviate from the object of the present invention
The shape and the material of the electrode 22 can be selected. Further, the conductive paper 21 is not limited to the above-mentioned material and manufacturing method, but is generally a mixed fiber of an insulating fiber and a conductive carbon fiber, which is a paper.
Expansion of fibers in response to changes in humidity, resulting in changes in the sheet resistance of the conductive paper due to changes in the contact resistance of the carbon fibers, and a unique relationship is obtained between the sheet resistance R and the relative humidity H. Therefore, any of them can be used as a humidity sensor in principle. However, since it is excellent in stability of RH characteristics, linearity, etc., as compared with the conductive paper having the above-described structure and manufacturing method, it can be said that it is optimal at present. This conductive paper is a commercially available product that is wound around a winding conductor to relax the electric field at the winding end of the armature winding of a large-capacity rotating machine. Since the amount used as a humidity sensor is small, the humidity sensor is inexpensive.
【００１４】[0014]
【発明の効果】この発明は前述のように、絶縁性繊維に
所定の割合のカーボン繊維を混合して製作された導電紙
の所定の形状、寸法のものに電圧を印加して電流を流し
これから求められる抵抗値を測定信号にすると、湿度が
変化すると絶縁性繊維の膨張の程度が変化し、これによ
ってカーボン繊維同士の接触抵抗が変化することによっ
て導電紙の面積抵抗が変化する。この面積抵抗の変化が
前述の湿度センサの抵抗変化となっ測定されるので、相
対湿度に一義的な対応のある抵抗値を得られる。また、
絶縁性繊維として全芳香族ポリアミド繊維を採用し、導
電紙としてこの全芳香族ポリアミド繊維とカーボン繊維
との混合繊維を湿式抄紙により製作したものを採用する
と、この導電紙の相対湿度−面積抵抗特性は相対湿度が
５０〜９５％の範囲で両対数目盛りで直線になる特性を
持ち、しかも、面積抵抗は相対湿度の約１０乗で変化す
るので僅かの相対湿度の変化に対して抵抗値が大きく変
化することから精度のよい湿度センサになるという効果
が得られる。更に、湿度センサとして必要な導電紙の量
は僅かであり、また、このような導電紙は市販品なので
安価な湿度センサになるという効果も得られる。As described above, according to the present invention, a voltage is applied to a conductive paper having a predetermined shape and size, which is produced by mixing insulating fibers with a predetermined ratio of carbon fibers, and an electric current is applied to the conductive paper. When the required resistance value is used as a measurement signal, the degree of expansion of the insulating fibers changes when the humidity changes, which changes the contact resistance between the carbon fibers and thus the area resistance of the conductive paper. Since this change in sheet resistance is measured as the change in resistance of the humidity sensor described above, the resistance value uniquely corresponding to the relative humidity can be obtained. Also,
When the wholly aromatic polyamide fiber is adopted as the insulating fiber and the mixed fiber of the wholly aromatic polyamide fiber and the carbon fiber is manufactured by wet papermaking as the conductive paper, the relative humidity-area resistance characteristic of the conductive paper is Has a characteristic that the relative humidity is linear on a logarithmic scale in the range of 50 to 95%. Moreover, since the sheet resistance changes with about 10th power of the relative humidity, the resistance value is large with respect to a slight change in the relative humidity. Since the humidity sensor changes, it is possible to obtain an effect that the humidity sensor has high accuracy. Furthermore, the amount of conductive paper required for the humidity sensor is small, and since such conductive paper is a commercially available product, it is possible to obtain an inexpensive humidity sensor.
【図１】この発明の実施例としての湿度センサを使用し
た湿度監視装置の概念図FIG. 1 is a conceptual diagram of a humidity monitoring device using a humidity sensor as an embodiment of the present invention.
【図２】導電紙の２０°Ｃにおける面積抵抗率Ｒ−相対
湿度Ｈの特性を示すグラフFIG. 2 is a graph showing the characteristics of area resistivity R-relative humidity H of conductive paper at 20 ° C.
２ 湿度センサ ２１ 導電紙 ２２ 電極 ４ 測定リード ５ 抵抗測定器 ６ 記録計 ８ 恒温恒湿槽 2 Humidity sensor 21 Conductive paper 22 Electrode 4 Measuring lead 5 Resistance measuring instrument 6 Recorder 8 Constant temperature and humidity chamber
Claims (2)
混合してなる導電紙の所定の形状寸法の抵抗値を測定信
号としてなることを特徴とする湿度センサ。1. A humidity sensor characterized in that a resistance value of a conductive paper made of a mixture of insulating fibers and carbon fibers in a predetermined ratio is used as a measurement signal.
り、導電紙がこの全芳香族ポリアミド繊維とカーボン繊
維との混合繊維を湿式抄紙により製作してなることを特
徴とする請求項１記載の湿度センサ。2. The insulating fiber is a wholly aromatic polyamide fiber, and the conductive paper is produced by wet-making a mixed fiber of the wholly aromatic polyamide fiber and the carbon fiber. Humidity sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4157091A JPH063307A (en) | 1992-06-17 | 1992-06-17 | Humidity sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4157091A JPH063307A (en) | 1992-06-17 | 1992-06-17 | Humidity sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH063307A true JPH063307A (en) | 1994-01-11 |
Family
ID=15642053
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4157091A Pending JPH063307A (en) | 1992-06-17 | 1992-06-17 | Humidity sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH063307A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106595977A (en) * | 2016-12-16 | 2017-04-26 | 国家电网公司 | Equipment insulation oil leakage monitoring alarm apparatus |
| CN109324091A (en) * | 2018-04-11 | 2019-02-12 | 湖北大学 | A kind of preparation method of the intellectual material for being suitable for moist sensing based on controllable asymmetric swelling system |
| CN110739096A (en) * | 2018-10-20 | 2020-01-31 | 嘉兴学院 | conductive materials for sensor and preparation method thereof |
-
1992
- 1992-06-17 JP JP4157091A patent/JPH063307A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106595977A (en) * | 2016-12-16 | 2017-04-26 | 国家电网公司 | Equipment insulation oil leakage monitoring alarm apparatus |
| CN109324091A (en) * | 2018-04-11 | 2019-02-12 | 湖北大学 | A kind of preparation method of the intellectual material for being suitable for moist sensing based on controllable asymmetric swelling system |
| CN109324091B (en) * | 2018-04-11 | 2020-12-29 | 湖北大学 | Preparation method of intelligent material suitable for sensing humid environment |
| CN110739096A (en) * | 2018-10-20 | 2020-01-31 | 嘉兴学院 | conductive materials for sensor and preparation method thereof |
| CN110739096B (en) * | 2018-10-20 | 2021-01-08 | 嘉兴学院 | Conductive material for sensor and preparation method thereof |
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