JPS6263852A - Capacity type humidity sensor compensating temperature - Google Patents

Capacity type humidity sensor compensating temperature

Info

Publication number
JPS6263852A
JPS6263852A JP61165684A JP16568486A JPS6263852A JP S6263852 A JPS6263852 A JP S6263852A JP 61165684 A JP61165684 A JP 61165684A JP 16568486 A JP16568486 A JP 16568486A JP S6263852 A JPS6263852 A JP S6263852A
Authority
JP
Japan
Prior art keywords
sensor
organic polymer
temperature
humidity sensor
thin film
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.)
Granted
Application number
JP61165684A
Other languages
Japanese (ja)
Other versions
JPH0340334B2 (en
Inventor
ベイヨ・アンチカイネン
ヨウコ・ヤラバ
エーロー・サラスマー
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vaisala Oy
Original Assignee
Vaisala Oy
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Vaisala Oy filed Critical Vaisala Oy
Publication of JPS6263852A publication Critical patent/JPS6263852A/en
Publication of JPH0340334B2 publication Critical patent/JPH0340334B2/ja
Granted legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/22Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance
    • G01N27/223Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance for determining moisture content, e.g. humidity
    • G01N27/225Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance for determining moisture content, e.g. humidity by using hygroscopic materials

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
  • Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。
(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 (産業上の利用分野) 本発明は、インピーダンスの変化に基づいて作動する電
気的湿度センサ、特に感湿剤を有機重合体で形成し、温
度補償された容量型altセンサに関するものである。
DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides an electrical humidity sensor that operates based on changes in impedance, in particular a temperature-compensated capacitive alt sensor in which the moisture sensitizer is formed of an organic polymer. It is related to sensors.

(゛従来の技術) インピーダンスの変化が測定すべき湿度に比例するよう
になっている電気検出系を備えたいくつかの湿度センサ
が知られている。この種類の湿度センサは例えば米国特
許第 3168829号、米国特許第3330941号および
フィンランド国特許第48229号の各明細書に記載さ
れている。
(Prior Art) Several humidity sensors are known that are equipped with an electrical detection system in which the change in impedance is proportional to the humidity to be measured. Humidity sensors of this type are described, for example, in US Pat. No. 3,168,829, US Pat. No. 3,330,941 and Finnish Patent No. 48,229.

フィンランド国特許第48229号明細書に記載されて
いる容量型湿度センサでは、誘電材が有機重合体膜から
なり、その誘電係数が有機重合体膜に吸収された水の量
の関数である。
In the capacitive humidity sensor described in Finnish Patent No. 48229, the dielectric material consists of an organic polymer film, the dielectric coefficient of which is a function of the amount of water absorbed into the organic polymer film.

(発明が解決しようとする問題点) これら湿度センサおよびインピーダンスの変化に基づく
別の湿度センサ゛では、特に高い湿度を測定するときに
望ましくない現象が存する。
(Problems to be Solved by the Invention) These humidity sensors and other humidity sensors based on changes in impedance have undesirable phenomena, especially when measuring high humidity.

この種の現象は例えば種々の要因から生じるセンサの緩
いクリープである。この場合に問題とな°るのは一般に
可逆現象であり、この発明の目的は、センサの応答性を
増大させることによってこれら現象の抑制を改善しかつ
特に例えば90%を越えるような高い相対湿度を測定す
る際の測定精度を向上させた容量型湿度センサを提供す
るにある。
A phenomenon of this kind is, for example, a slow creep of the sensor that results from various factors. Problems in this case are generally reversible phenomena, and the object of the invention is to improve the suppression of these phenomena by increasing the responsiveness of the sensor and, in particular, to improve the suppression of these phenomena at high relative humidity, e.g. An object of the present invention is to provide a capacitive humidity sensor with improved measurement accuracy when measuring humidity.

(問題点を解決するための手段) 上述したおよび後述する目的を達成するため、本発明は
、ベース11上の一対の底部接触体12、前記底部接触
体12を被覆する有機重合体絶縁薄膜13、前記有機重
合体薄膜I3を被覆する水蒸気透過性でかつ前記底部接
触体のいずれとも電気的に接触しない表面接触体14、
前記底部接触体12の各々に接触する測定装置20から
なる容1型湿度センサ10において、前記有機重合体薄
膜13の温度T を測定する温度センサ15が前記有機
゛重合体薄M13に接触して配置され、周囲温度T を
測定する温度センサ17が前記湿度センサ10の外部に
配置され、かつ前記湿度センサ10は前記 T≦ −To)に比例して調節される前記測定装置20
からの測定電流lにより加熱されることを特徴とする。
(Means for Solving the Problems) In order to achieve the above-mentioned and below-mentioned objects, the present invention provides a pair of bottom contacts 12 on a base 11, an organic polymer insulating thin film 13 covering said bottom contacts 12. , a water vapor permeable surface contact member 14 covering the organic polymer thin film I3 and not in electrical contact with any of the bottom contact members;
In the container type humidity sensor 10 comprising a measuring device 20 in contact with each of the bottom contact members 12, a temperature sensor 15 for measuring the temperature T of the organic polymer thin film 13 is in contact with the organic polymer thin film M13. The measuring device 20 is arranged such that a temperature sensor 17 measuring the ambient temperature T is arranged outside the humidity sensor 10, and the humidity sensor 10 is adjusted in proportion to the T≦−To.
It is characterized in that it is heated by the measurement current l from .

(実施例) 以下、有機電合体を感湿剤とする容量型湿度センサを図
示した添(=j図面を参照しつつ本発明を実施例につき
詳述する。
(Example) Hereinafter, the present invention will be described in detail with reference to the attached drawing, which shows a capacitive humidity sensor using an organic electrolyte as a moisture sensitive agent.

第1図および第2図に示す湿度センサ自身は、フィンラ
ンド国特許出願第48229号明細書に記載されたもの
である。センサ10はガラスのような不活性材料で作ら
れたベース11上に支持される。ベース11上には薄膜
技術で知られている方法により作成された金属メッキ底
部接触体12が存し、この底部接触体上には接触導線2
Iが端子16において蝋付けされ、容量は第1図にブロ
ック20.22で示された装置によって検出され、測定
されかつ表示される。
The humidity sensor itself shown in FIGS. 1 and 2 is described in Finnish patent application no. 48229. Sensor 10 is supported on a base 11 made of an inert material such as glass. On the base 11 there is a metal-plated bottom contact 12 made by methods known in thin film technology, on which contact conductors 2
I is brazed at terminal 16 and the capacitance is detected, measured and displayed by the apparatus shown in block 20.22 in FIG.

センサ・10の活性材料はlOμ晶程度の厚さの有機重
合体薄膜13である。有機重合体薄膜13上には、両底
部接触体12のどちらとも電気的に接触しない水蒸気を
透過する薄い表面接触体14が真空蒸発またはスパッタ
リングで被着され或いは化学的に作られる。測定される
容量CyLは、dおよびe(第2図)の区域における底
部接触体12と表面接触体14の間に形成される2つの
容量の直列接続から形成される。
The active material of sensor 10 is a thin organic polymer film 13 on the order of lOμ thick. A thin water vapor permeable surface contact 14, which is not in electrical contact with either of the bottom contacts 12, is deposited on the organic polymer film 13 by vacuum evaporation or sputtering, or is chemically produced. The measured capacitance CyL is formed from the series connection of two capacitances formed between the bottom contact 12 and the surface contact 14 in the areas d and e (FIG. 2).

(作用) 水分子が有機重合体薄膜13の感湿材料に吸収されると
、水の定着が2つの相異なる現象によって起こる。
(Function) When water molecules are absorbed into the moisture-sensitive material of the organic polymer thin film 13, water fixation occurs through two distinct phenomena.

1つの定着は分子レベルで起こり、容量Cの変化として
迅速かつほぼ直線的な感応を生じる。
One fixation occurs at the molecular level, resulting in a rapid and nearly linear response as the capacitance C changes.

別の現象は極めて湿度の高い状懸(一般に90%を超え
る相対湿度)で起こるいわゆる膨潤効果であって、これ
において水は有機重合体1膜13の感湿材料のポケット
状空洞の中に閉じ込あられる。この現象は前述の現象よ
りかなり遅く、かつ高湿度測定時にセンサのクリープを
生じさせる。
Another phenomenon is the so-called swelling effect that occurs in extremely humid conditions (generally above 90% relative humidity), in which water becomes trapped within the pocket-like cavities of the moisture-sensitive material of the organic polymer 1 membrane 13. It's crowded. This phenomenon is much slower than the previous one and causes sensor creep when measuring high humidity.

第1図に示すように、センサには適当な周波数の測定電
流eが供給され、この電流は湿度センサ10で測定され
る湿度の基礎をなす。何述した理由により、特に高い湿
度レベルにおいて、端子1Gで測定されるインピーダン
スZ は純粋な容量でなく、成る抵抗成分を有するので
測定すべき容量は (即ち、直列に接続された抵抗と容量)で表示される。
As shown in FIG. 1, the sensor is supplied with a measuring current e of a suitable frequency, which current forms the basis of the humidity measured by the humidity sensor 10. For the reasons mentioned above, especially at high humidity levels, the impedance Z measured at terminal 1G is not a pure capacitance, but has a resistive component consisting of a resistive component, so the capacitance to be measured is is displayed.

ここで、Rは誘電電合体の損失抵抗であり、Cは測定さ
れたインピーダンスの容置 量成分′である。高い温度レベルにおいて、上述した膨
潤効果は損失抵抗成分を増大させる。それ故、成分Rの
中に生じかつセンサを加熱する損失効果WはI”Hに等
しい(W=lR)O。
Here, R is the loss resistance of the dielectric combination, and C is the capacitance component of the measured impedance. At high temperature levels, the swelling effect described above increases the loss resistance component. Therefore, the loss effect W occurring in the component R and heating the sensor is equal to I''H (W=lR)O.

ここで、■は定格測定電流゛(二乗平均電流)である。Here, ■ is the rated measurement current (root mean square current).

この発明によればセンサの加熱は、センサによって吸収
された有害な湿分を温度上昇と共に感湿材料から迅速に
離脱させる作用と、周囲空気より若干温かいセンサが包
囲空気を加温して境界表面の空気の相対湿度をセンサの
作動の点から見て有害な高さまで上昇させないようにす
る作用とを有し、或いはこれら両件用のいずれかを有す
ると考えられる。
According to this invention, the heating of the sensor has two effects: the harmful moisture absorbed by the sensor is quickly released from the moisture-sensitive material as the temperature increases, and the sensor, which is slightly warmer than the surrounding air, warms the surrounding air and surfaces the boundary surface. The relative humidity of the air may be prevented from increasing to a height that is harmful from the point of view of sensor operation, or both.

第1図に示されるように、センサ10の有機重合体薄膜
13はセンサ自身に直接向けられる電流Iによって加温
される。この電流■はセンサ自身の測定電流と同じもの
であり、測定される容量の誘電材料(即ち、有機重合体
薄膜13)に損失を生じさせる。第1図に示すように、
前述の加温は、実際上センサーOの入力電圧Uを本発明
から見て適当なレベルまで上昇させることによって遂行
される。本発明のこの実施例の利点として、これは高湿
度のときに大きく加温され(比較的高い損失抵抗゛R)
、加熱を要しない区い湿度レベルのときに加温および損
失の双方が低い。故に、本発明による加温は、著しい誤
差即ち湿度測定における補正の必要を生じない。
As shown in FIG. 1, the organic polymer film 13 of sensor 10 is heated by a current I directed directly into the sensor itself. This current {circle around (2)} is the same as the sensor's own measuring current and causes losses in the dielectric material (ie, the organic polymer thin film 13) of the capacitance being measured. As shown in Figure 1,
The above-mentioned heating is practically accomplished by increasing the input voltage U of the sensor O to a level suitable from the point of view of the invention. An advantage of this embodiment of the invention is that it warms up significantly at high humidity (relatively high loss resistance R).
Both heating and losses are low at humidity levels that do not require heating. Therefore, heating according to the invention does not result in significant errors or the need for correction in humidity measurements.

第1図に示した実施例において、誘電材料の温度T は
有機重合体薄膜13に連結配置された温度センサ15に
よって測定され、この測定結果は有機重合体厚J![1
3の加温に対して適当に使用される(導線38)。実際
上、これは温度T の開it(これは経験に従って選択
される)として入力電圧Uを調節することによって行わ
れる。
In the embodiment shown in FIG. 1, the temperature T of the dielectric material is measured by a temperature sensor 15 arranged in conjunction with the organic polymer thin film 13, and the result of this measurement is determined by the organic polymer thickness J! [1
3 (conductor 38). In practice, this is done by adjusting the input voltage U as the temperature T 1 (which is chosen according to experience).

第1図に示したように、周囲温度T もセンす17で測
定され、この測定結果は測定装置20へ送られてセンサ
10の加温の関節に適当な方法、で使用される。第1図
において、ブロック22は相対湿度(RH)指示器をし
めす。
As shown in FIG. 1, the ambient temperature T 2 is also measured by the sensor 17 and the result of this measurement is sent to a measuring device 20 and used in a suitable manner for the heating joint of the sensor 10. In FIG. 1, block 22 represents a relative humidity (RH) indicator.

上述したように、湿度センサ自身によって与えられる湿
度情報を、加熱モネルギの調節に使用できる。温度T 
およびT によって与えられる情報も、例えば90%を
越えるような高い相対湿度のときに測定結果を温度差Δ
T = T。
As mentioned above, the humidity information provided by the humidity sensor itself can be used to adjust the heating energy. Temperature T
The information given by
T = T.

−T  に比例する信号で補正するよう温度を調′ O 節するために使用できる。- Adjust the temperature to compensate with a signal proportional to T. It can be used to make a clause.

成る用途では、実際の測定作業の間加熱を遮断し、別の
期間中にこの加熱をおこなって水分子の有害な定着を防
止するのが有利である。
In such applications, it is advantageous to shut off the heating during the actual measuring operation and carry out this heating during another period to prevent harmful fixation of water molecules.

本発明は例示の目的で記載した上記の実施例のみに限定
されず、本発明の思想および範囲内において多くの設計
変更が可能である。
The invention is not limited only to the embodiments described above for illustrative purposes, but many modifications are possible within the spirit and scope of the invention.

(発明の効果) 本発明に係る温度補償の容量型湿度センサによると、高
い相対湿度の場合でも正確な湿度値が迅速に測定可能と
なる。
(Effects of the Invention) According to the temperature compensated capacitive humidity sensor according to the present invention, accurate humidity values can be quickly measured even in the case of high relative humidity.

【図面の簡単な説明】[Brief explanation of drawings]

第1面は本発明に係る温度補償の容量型湿度センサの1
部をブロック線図で示した線図、第2図は第1図に示し
た実際の容量型湿度センサの■−■線断面図である。 10・・・湿度センサ  −ト・・ベース12パ・・底
部接触体 】3・・・有機重合体薄膜 14・・・表面接触体 15.17・・・温度センサ −6・・・端子18.1
9.21・・・導線  20測定装置22・・・指示器
   To  ・・・周囲温度T ・・・センサ温度
The first side shows one of the temperature compensated capacitive humidity sensors according to the present invention.
FIG. 2 is a cross-sectional view taken along the line ■--■ of the actual capacitive humidity sensor shown in FIG. 1. 10...Humidity sensor -T...Base 12...Bottom contact body]3...Organic polymer thin film 14...Surface contact body 15.17...Temperature sensor -6...Terminal 18. 1
9.21...Conducting wire 20Measuring device 22...Indicator To...Ambient temperature T...Sensor temperature

Claims (1)

【特許請求の範囲】[Claims] (1)ベース11上の一対の底部接触体12、前記底部
接触体12を被覆する有機重合体絶縁薄膜13、前記有
機重合体薄膜13を被覆する水蒸気透過性でかつ前記底
部接触体のいずれとも電気的に接触しない表面接触体1
4、前記底部接触体12の各々に接触する測定装置20
からなる容量型湿度センサ10において、前記有機重合
体薄膜13の温度T_sを測定する温度センサ15が前
記有機重合体薄膜13に接触して配置され、周囲温度T
_oを測定する温度センサ17が前記湿度センサ10の
外部に配置され、かつ前記湿度センサ10は前記T_s
−T_oに比例して調節される前記測定装置20からの
測定電流Iにより加熱されることを特徴とする温度補償
の容量型湿度センサ。
(1) A pair of bottom contact members 12 on the base 11, an organic polymer insulating thin film 13 covering the bottom contact members 12, and a water vapor permeable film covering the organic polymer thin film 13 that is not connected to any of the bottom contact members. Surface contact body 1 that does not make electrical contact
4. Measuring device 20 that contacts each of the bottom contact bodies 12
In the capacitive humidity sensor 10, a temperature sensor 15 for measuring the temperature T_s of the organic polymer thin film 13 is placed in contact with the organic polymer thin film 13, and the temperature sensor 15 measures the temperature T_s of the organic polymer thin film 13.
A temperature sensor 17 for measuring _o is arranged outside the humidity sensor 10, and the humidity sensor 10 measures the T_s
- a temperature-compensated capacitive humidity sensor, characterized in that it is heated by the measuring current I from the measuring device 20, which is adjusted in proportion to T_o;
JP61165684A 1977-12-02 1986-07-16 Capacity type humidity sensor compensating temperature Granted JPS6263852A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FI773680A FI58402C (en) 1977-12-02 1977-12-02 FARING EQUIPMENT WITHOUT ELECTRICAL EQUIPMENT HOS EN ELECTRICAL FUNCTIONAL EQUIPMENT
FI773680 1977-12-02

Publications (2)

Publication Number Publication Date
JPS6263852A true JPS6263852A (en) 1987-03-20
JPH0340334B2 JPH0340334B2 (en) 1991-06-18

Family

ID=8511289

Family Applications (2)

Application Number Title Priority Date Filing Date
JP14730878A Granted JPS5494090A (en) 1977-12-02 1978-11-30 Method of minimizing undesirable characteristics of humidity sensor
JP61165684A Granted JPS6263852A (en) 1977-12-02 1986-07-16 Capacity type humidity sensor compensating temperature

Family Applications Before (1)

Application Number Title Priority Date Filing Date
JP14730878A Granted JPS5494090A (en) 1977-12-02 1978-11-30 Method of minimizing undesirable characteristics of humidity sensor

Country Status (9)

Country Link
JP (2) JPS5494090A (en)
AU (1) AU4203378A (en)
BR (1) BR7807935A (en)
DE (1) DE2851686C2 (en)
FI (1) FI58402C (en)
FR (1) FR2410821A1 (en)
GB (1) GB2011093A (en)
IT (1) IT1100442B (en)
ZA (1) ZA786573B (en)

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US4352059A (en) * 1980-06-13 1982-09-28 Massachusetts Institute Of Technology Determination of moisture level in materials
DE3513065C1 (en) * 1985-04-12 1986-01-02 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., 8000 München Probe for measuring the relative humidity of the air without hysteresis
EP0317871A3 (en) * 1987-11-24 1991-03-06 Siemens Aktiengesellschaft Probe for detecting gases
FI82554C (en) * 1988-11-02 1991-03-11 Vaisala Oy Calibration procedure for measuring the relative content of gas or steam
FI95626C (en) * 1993-09-29 1996-02-26 Vaisala Oy Procedure and arrangement for measuring humidity, especially in radio probes
FI99164C (en) * 1994-04-15 1997-10-10 Vaisala Oy Method for measuring the dew point or gas content and equipment for predicting freezing
DE4426736C2 (en) * 1994-07-28 1999-12-23 Mannesmann Vdo Ag Moisture sensor for a window pane of a motor vehicle
AT1469U1 (en) * 1996-04-10 1997-05-26 E & E Elektronik Gmbh METHOD FOR DETERMINING ABSOLUTE HUMIDITY
DE19729697C1 (en) 1997-07-11 1999-02-11 Mannesmann Vdo Ag Arrangement for determining the relative humidity
DE19953195A1 (en) * 1999-11-05 2001-05-23 Preh Elektro Feinmechanik Sensor to detect moisture, for commercial vehicle brake system; has printed circuit board with two tracks at different voltages, which are connected, short-circuited or interrupted by moisture
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AU4203378A (en) 1979-06-07
IT7830461A0 (en) 1978-12-01
GB2011093A (en) 1979-07-04
DE2851686A1 (en) 1979-06-07
FI58402B (en) 1980-09-30
FI773680A (en) 1979-06-03
FI58402C (en) 1981-01-12
DE2851686C2 (en) 1981-10-01
IT1100442B (en) 1985-09-28
FR2410821A1 (en) 1979-06-29
BR7807935A (en) 1979-07-31
ZA786573B (en) 1980-03-26
FR2410821B1 (en) 1984-04-20
JPH0340334B2 (en) 1991-06-18
JPS5494090A (en) 1979-07-25
JPH0151771B2 (en) 1989-11-06

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