JPH0194255A - Gas-in-oil sensor - Google Patents
Gas-in-oil sensorInfo
- Publication number
- JPH0194255A JPH0194255A JP25131187A JP25131187A JPH0194255A JP H0194255 A JPH0194255 A JP H0194255A JP 25131187 A JP25131187 A JP 25131187A JP 25131187 A JP25131187 A JP 25131187A JP H0194255 A JPH0194255 A JP H0194255A
- Authority
- JP
- Japan
- Prior art keywords
- film
- hydrogen gas
- gas
- oil
- membrane
- 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
- 229920001721 polyimide Polymers 0.000 claims abstract description 18
- 229910044991 metal oxide Inorganic materials 0.000 claims abstract description 15
- 150000004706 metal oxides Chemical class 0.000 claims abstract description 15
- 239000009719 polyimide resin Substances 0.000 claims abstract description 10
- 239000010408 film Substances 0.000 claims description 21
- 239000010409 thin film Substances 0.000 claims description 16
- 239000000758 substrate Substances 0.000 claims description 7
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 abstract description 34
- 239000007789 gas Substances 0.000 abstract description 19
- 239000004642 Polyimide Substances 0.000 abstract description 4
- 239000012528 membrane Substances 0.000 abstract 6
- 230000005540 biological transmission Effects 0.000 abstract 2
- 239000011248 coating agent Substances 0.000 abstract 1
- 238000000576 coating method Methods 0.000 abstract 1
- 238000000034 method Methods 0.000 description 7
- 239000012466 permeate Substances 0.000 description 5
- 239000010931 gold Substances 0.000 description 3
- -1 polyethylene terephthalate Polymers 0.000 description 3
- 230000005856 abnormality Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910052737 gold Inorganic materials 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 229920000139 polyethylene terephthalate Polymers 0.000 description 2
- 239000005020 polyethylene terephthalate Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 2
- 229920006163 vinyl copolymer Polymers 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 229920001038 ethylene copolymer Polymers 0.000 description 1
- 125000000816 ethylene group Chemical group [H]C([H])([*:1])C([H])([H])[*:2] 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 238000005268 plasma chemical vapour deposition Methods 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
Landscapes
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
この発明は油中に溶存している水素ガスの検知に好適な
油中ガスセンサに関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a gas-in-oil sensor suitable for detecting hydrogen gas dissolved in oil.
（従来の技術）
周知のように変圧器、コンデンサ、リアクトルその他の
油入電気機器においては、局部的にコロナ放電が発生す
るような異常或いは局部加熱により、絶縁油が分解され
て水素ガスが発生することが知られている。したがって
水素ガスを検出することによって、電気機器の異常を、
事故が発生する以前に検知することができるようになる
。(Prior art) As is well known, in oil-filled electrical equipment such as transformers, capacitors, reactors, etc., insulating oil is decomposed and hydrogen gas is generated due to abnormalities such as local corona discharge or local heating. It is known to do. Therefore, by detecting hydrogen gas, abnormalities in electrical equipment can be detected.
It will be possible to detect accidents before they occur.
従来ではこのような水素ガスの検出に、電気機器より絶
縁油を採取し、これより溶存ガスを抽出し、これをガス
クロマトグラフにより分析するようにしている。しかし
このような手段によると、電気機器の設置現場では分析
できないし、またオンライン分析ができないなどの不便
がある。Conventionally, such hydrogen gas has been detected by collecting insulating oil from electrical equipment, extracting dissolved gas from this, and analyzing it using a gas chromatograph. However, with this method, there are inconveniences such as analysis cannot be performed at the site where the electrical equipment is installed, and online analysis cannot be performed.
これを解決するために、絶縁性の基板の表面に水素ガス
に反応して抵抗値が変化する金属酸化物の薄膜を設け、
その表面に一対の電極を形成してセンサ本体を構成し、
その表面をポリイミド樹脂からなる薄膜により被覆して
油中ガスセンサとし、これを油中に浸漬して使用するよ
うにしたものが本発明者によって別途提案された。To solve this problem, we created a thin film of metal oxide on the surface of an insulating substrate whose resistance value changes in response to hydrogen gas.
A pair of electrodes is formed on the surface of the sensor body,
The present inventor has separately proposed a sensor in which the surface of the sensor is coated with a thin film made of polyimide resin to form a gas-in-oil sensor, which is used by being immersed in oil.
これによればポリイミド樹脂が水素ガスを選択透過する
特性を具備しているところから、これによって油中の水
素ガスがこのポリイミド樹脂からなる薄膜を選択透過し
、金属酸化物に反応して所要の水素ガスに反応するよう
になる。According to this, since polyimide resin has the property of selectively permeating hydrogen gas, hydrogen gas in the oil selectively permeates through the thin film made of this polyimide resin, reacts with metal oxides, and produces the required amount. Becomes reactive to hydrogen gas.
しかしポリイミド樹脂からなる膜を被覆した場合、その
膜が極めて薄いために、これを油中に浸漬したとき油が
この膜を透過してくることがあり、そのため透過してき
た油と金属酸化物とが反応してしまうことがある。金属
酸化物は表面が油に触れると、水素ガスに対するセンサ
機能が消失してしまうので、油との反応を確実に防止す
ることが肝要である。However, when a film made of polyimide resin is coated, the film is extremely thin, so when the film is immersed in oil, oil may permeate through the film, resulting in a combination of the permeated oil and metal oxides. may react. If the surface of a metal oxide comes into contact with oil, it loses its sensing function for hydrogen gas, so it is important to reliably prevent reactions with oil.
（発明が解決しようとする問題点）
この発明は油中に溶存している水素ガスの測定に際して
、金属酸化物とこれをポリイミド膜で被覆したセンサ本
体を使用する場合でも、ポリイミド膜を透過してくる油
によって金属酸化物が反応しないようにし、もって油中
の水素ガスを正確に測定できるようにすることを目的と
する。(Problems to be Solved by the Invention) When measuring hydrogen gas dissolved in oil, even when using a sensor body made of a metal oxide and a polyimide film covering the metal oxide, the present invention does not penetrate the polyimide film. The purpose of this method is to prevent metal oxides from reacting with incoming oil, thereby making it possible to accurately measure hydrogen gas in oil.
（問題点を解決するための手段）
この発明は金属酸化物とその表面に互いに向かい合う一
対の電極を形成することによってセンサ本体を構成し、
前記センサ本体の表面を、ポリイミド樹脂からなる薄膜
により被覆し、更に前記センサ本体をガス透過性フィル
ムで覆ってなることを特徴とする。(Means for Solving the Problems) The present invention constitutes a sensor body by forming a metal oxide and a pair of electrodes facing each other on the surface thereof,
The sensor body is characterized in that the surface of the sensor body is covered with a thin film made of polyimide resin, and the sensor body is further covered with a gas permeable film.
（実施例）
この発明の実施例を図によって説明すると、１はたとえ
ばポリエチレンテレフタレートのような樹脂からなるフ
ィルム状の基板（第２図、第３図参照。以下同じ。）、
或いはＡ１□０３，５ｉ０２などの無機絶縁材料からな
る基板、２は基板１の表面に設けられた金属酸化物から
なる薄膜である。これはたとえばＳｎＯ２、Ｔｉｅ□、
ｌ１ｌＯ３、Ｉｎｋ、その他の単体またはこれらのうち
の２種以上の複合体が使用できる。(Example) An example of the present invention will be described with reference to the drawings. 1 is a film-like substrate made of a resin such as polyethylene terephthalate (see FIGS. 2 and 3; the same applies hereinafter);
Alternatively, the substrate 2 is made of an inorganic insulating material such as A1□03, 5i02, etc., and 2 is a thin film made of a metal oxide provided on the surface of the substrate 1. This includes, for example, SnO2, Tie□,
L11O3, Ink, and other single substances or complexes of two or more of these can be used.
この種の金属酸化物類は、水素ガスによってその表面抵
抗が変化するものとして知られている。This type of metal oxide is known to have a surface resistance that changes with hydrogen gas.
なおこれらの金属酸化物の薄膜は、 ＩＶＤ法、ＩＢＳ
法、真空蒸着法、プラズマＣＶＤ法などによって適当に
設けられる。Note that thin films of these metal oxides can be prepared using the IVD method or IBS method.
It is appropriately provided by a method such as a method, a vacuum evaporation method, a plasma CVD method, or the like.
薄膜２の表面には互いに向かい合う一対の電極３が形成
される。これは図のように櫛型とするのが好ましい。電
極３はたとえばＡｕ、Ｐｄなどによって形成される。こ
のようにしてセンサ本体４が構成されるが、更にこのセ
ンサ本体４はポリイミド樹脂からなる薄膜５で被覆され
る。なお電極３にはリードが接続され外部に導出される
。A pair of electrodes 3 facing each other are formed on the surface of the thin film 2. This is preferably comb-shaped as shown in the figure. The electrode 3 is made of Au, Pd, etc., for example. The sensor main body 4 is constructed in this manner, and is further coated with a thin film 5 made of polyimide resin. Note that a lead is connected to the electrode 3 and led out to the outside.
センサ本体４はガス透過性フィルムたとえば、フッ素系
樹脂からなるフィルムで覆うようにする。The sensor main body 4 is covered with a gas permeable film, for example, a film made of fluororesin.
フッ素系樹脂は油を透過することがなく、また水素ガス
その他のガスに対する透過係数が、ポリイミド樹脂より
も大きい。Fluororesin does not allow oil to pass through it, and its permeability coefficient for hydrogen gas and other gases is greater than that of polyimide resin.
したがってフッ素系樹脂のフィルムで覆っておくと、こ
のフィルムによって油は確実に遮断されるとともに、こ
のフィルムを透過してきたガスのうち、水素ガスはポリ
イミドからなる薄膜により選択透過し、金属酸化物は確
実に水素ガスに反応するようになる。Therefore, if covered with a fluororesin film, this film will surely block oil, and among the gases that permeate through this film, hydrogen gas will selectively permeate through the thin film made of polyimide, and metal oxides will be It will definitely react to hydrogen gas.
これを第１図によって説明すると、６はたとえば変圧器
のタンクで、その側壁の一部に窓７を開け、ここを蓋８
で閉塞自在としておく。蓋８には支柱９を介してセンサ
本体４を、タンク６の内部に入り込むように取り付けて
おく。窓７の周縁のフランジ１０を利用して、センサ本
体４を覆うようにフッ素系樹脂からなる筒状のフィルム
１１を取り付ける。To explain this with reference to Fig. 1, 6 is a transformer tank, for example, and a window 7 is opened in a part of the side wall of the tank, and a lid 8 is inserted into the window 7.
Let it be closed freely. The sensor main body 4 is attached to the lid 8 via a support 9 so as to fit inside the tank 6. A cylindrical film 11 made of fluororesin is attached using a flange 10 at the periphery of the window 7 so as to cover the sensor body 4.
具体的にはフィルム１１を、筒状に丸めた金網１２の内
面に支持することによって保護するとともに、この金網
１２の基端をフランジ１０の先端に溶接などによって固
定する。金［１２の先端は保護板１３の内面に溶接など
によって固定する。Specifically, the film 11 is protected by being supported on the inner surface of a wire mesh 12 rolled into a cylindrical shape, and the base end of the wire mesh 12 is fixed to the tip of the flange 10 by welding or the like. The tip of the gold plate 12 is fixed to the inner surface of the protective plate 13 by welding or the like.
フィルム１１はパツキン１４、押え部材１５を介して、
フランジ１０、保護板１３にビス１６によって固定され
る。なお１７は○リング、１８はセンサ本体４からのリ
ードに接続されるケーブル、１９は防雨用のカバーであ
る。The film 11 is passed through the packing 14 and the pressing member 15,
It is fixed to the flange 10 and the protection plate 13 with screws 16. Note that 17 is a ring, 18 is a cable connected to a lead from the sensor body 4, and 19 is a rainproof cover.
以上の構成によれば、タンク６内の油はフィルム１１に
よって確実に遮断され、センサ本体４の周囲にまでは到
達しない。しかし水素ガスその他のガスに対しては、こ
のフィルム１１は透過係数が大きいので、これらのガス
は確実に透過してくる。According to the above configuration, the oil in the tank 6 is reliably blocked by the film 11 and does not reach around the sensor body 4. However, since the film 11 has a large permeability coefficient for hydrogen gas and other gases, these gases will certainly pass through.
一方水素ガスに対してはポリイミド膜５は透過６一
係数が他のガスよりも大きいので、前記のようにフィル
ム１１を透過してきたガスのうち、水素ガスがポリイミ
ドＭ５を選択透過して金属酸化物からなる薄膜２に接触
して反応する。これによってその薄Ｍ２の表面抵抗が、
水素ガスの濃度に応じて変化する。したがってこの表面
抵抗を電極３ｍの抵抗として検知することによって、水
素ガスの濃度を知ることができるようになる。On the other hand, for hydrogen gas, the polyimide film 5 has a permeation coefficient 6 larger than other gases, so among the gases that have permeated through the film 11 as described above, hydrogen gas selectively permeates through the polyimide M5 and oxidizes the metal. It comes into contact with the thin film 2 made of the substance and reacts. As a result, the surface resistance of the thin M2 becomes
It changes depending on the concentration of hydrogen gas. Therefore, by detecting this surface resistance as the resistance of the electrode 3m, the concentration of hydrogen gas can be determined.
なおフィルム１１のためのフッ素系樹脂としては、４フ
ッ化エチレン−パーフロロアルキルビニル共重合物、４
フッ化エチレン−６フツ化プロピレン共重合物、４フッ
化エチレン−エチレン共重合物、４フツ化エチレンなど
が使用できる。The fluororesin for the film 11 includes tetrafluoroethylene-perfluoroalkyl vinyl copolymer, 4
Fluorinated ethylene-hexafluorinated propylene copolymer, tetrafluorinated ethylene-ethylene copolymer, tetrafluorinated ethylene, etc. can be used.
次にこの発明の実験例について説明する。厚さ１５μｍ
、５０ｍｍ平方のポリエチレンテレフタレートフィルム
からなる基板１の表面に１．ＴＶＤ法により厚さ１．０
μｍに金属酸化物であるＳｎＯ□の薄膜２を設け、この
薄膜２の表面にＡｕによって櫛状の電極３を形成して、
センサ本体４を構成し、これにプラズマ重合法によりポ
リイミド膜５を約１．０μｍの厚さに形成した。これを
第１図に示すように変圧器内で、４フッ化エチレン−パ
ーフロロアルキルビニル共重合物からなるフィルム１１
により覆うように設定した。Next, an experimental example of this invention will be explained. Thickness 15μm
, 1. on the surface of a substrate 1 made of a 50 mm square polyethylene terephthalate film. Thickness 1.0 by TVD method
A thin film 2 of SnO□, which is a metal oxide, is provided in μm, and a comb-shaped electrode 3 is formed with Au on the surface of this thin film 2.
A sensor body 4 was constructed, and a polyimide film 5 of about 1.0 μm thick was formed thereon by plasma polymerization. As shown in FIG. 1, a film 11 made of tetrafluoroethylene-perfluoroalkyl vinyl copolymer
It was set to cover the
第４図は第１図のように水素ガスが溶存している変圧器
の油中に浸漬して、そのときの水素ガス濃度に対する抵
抗変化率（水素ガスと反応した後の抵抗値／反応前の初
期の抵抗値）をグラフにした特性曲線である。これによ
れば水素ガス濃度に対して抵抗変化率は、はぼ直線的に
変化していることが判明する。Figure 4 shows the rate of change in resistance (resistance after reacting with hydrogen gas/before reaction) when immersed in the oil of a transformer in which hydrogen gas is dissolved as shown in Figure 1. This is a characteristic curve that is a graph of the initial resistance value of According to this, it is clear that the resistance change rate changes approximately linearly with respect to the hydrogen gas concentration.
第５図は同じ曲内の水素ガス濃度を、ガスクロマトグラ
フによって測定したときの測定値Ａと、この発明による
ガスセンサによって測定したときの測定値（油中濃度換
算値）Ｂとの相関関係を示す特性曲線である。これによ
ると水素ガス濃度が５０ｐｐｍ以上のとき、両側定値Ａ
、Ｂは互いにほぼ同じ値を呈するようになる。Figure 5 shows the correlation between hydrogen gas concentration in the same song, measured value A when measured by a gas chromatograph, and measured value B (concentration in oil converted value) when measured by the gas sensor according to the present invention. It is a characteristic curve. According to this, when the hydrogen gas concentration is 50 ppm or more, both sides constant value A
, B have almost the same value.
以上の結果、この発明によるガスセンサによって水素ガ
ス濃度を計測するとき、その濃度に対応して感度よく抵
抗が変化するとともに、これによる測定値は、ガスクロ
マトグラフによる測定値とほぼ匹敵する正確な値となる
ことが理解される。As a result of the above, when the hydrogen gas concentration is measured by the gas sensor according to the present invention, the resistance changes with high sensitivity in response to the concentration, and the measured value is an accurate value that is almost comparable to the measured value by a gas chromatograph. It is understood that
（発明の効果）
以上詳述したようにこの発明によれば、油中に溶存する
水素ガス濃度の測定を、その測定対象の油の中に単に浸
漬するだけの簡単な操作で可能となるし、しかも油の透
過を確実に回避し、水素ガスに正確に反応させることが
できるようになるといった効果を奏する。(Effects of the Invention) As detailed above, according to the present invention, it is possible to measure the concentration of hydrogen gas dissolved in oil with a simple operation of simply immersing it in the oil to be measured. Moreover, it has the effect of reliably avoiding oil permeation and making it possible to react accurately with hydrogen gas.
第１図はこの発明の実施例を示す断面図、第２図はセン
サ本体の断面図、第３図は同正面図、第４図は抵抗変化
率を示す特性曲線図、第５図は測定値の相関関係を示す
特性曲線図である。
１・・・基板、２・・・薄膜、３・・・電極、４・・・
センサ本体５・・・薄膜、１１・・・フィルム、Fig. 1 is a sectional view showing an embodiment of the present invention, Fig. 2 is a sectional view of the sensor main body, Fig. 3 is a front view thereof, Fig. 4 is a characteristic curve diagram showing the rate of change in resistance, and Fig. 5 is a measurement FIG. 3 is a characteristic curve diagram showing a correlation between values. 1... Substrate, 2... Thin film, 3... Electrode, 4...
Sensor body 5... thin film, 11... film,
Claims (1)
表面に互いに向かい合う一対の電極を形成することによ
ってセンサ本体を構成し、前記センサ本体の表面を、ポ
リイミド樹脂からなる薄膜により被覆し、更に前記セン
サ本体をガス透過性フィルムで覆ってなる油中ガスセン
サ。A sensor body is constructed by providing a thin film of metal oxide on the surface of an insulating substrate, forming a pair of electrodes facing each other on the surface, and covering the surface of the sensor body with a thin film made of polyimide resin. . A gas-in-oil sensor further comprising: the sensor body covered with a gas-permeable film.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25131187A JPH0194255A (en) | 1987-10-05 | 1987-10-05 | Gas-in-oil sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25131187A JPH0194255A (en) | 1987-10-05 | 1987-10-05 | Gas-in-oil sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0194255A true JPH0194255A (en) | 1989-04-12 |
Family
ID=17220918
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP25131187A Pending JPH0194255A (en) | 1987-10-05 | 1987-10-05 | Gas-in-oil sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0194255A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7228724B2 (en) | 2002-10-17 | 2007-06-12 | Advanced Technology Materials, Inc. | Apparatus and process for sensing target gas species in semiconductor processing systems |
| US7296458B2 (en) | 2002-10-17 | 2007-11-20 | Advanced Technology Materials, Inc | Nickel-coated free-standing silicon carbide structure for sensing fluoro or halogen species in semiconductor processing systems, and processes of making and using same |
| US7475588B2 (en) * | 2002-10-17 | 2009-01-13 | Advanced Technology Materials, Inc. | Apparatus and process for sensing fluoro species in semiconductor processing systems |
| KR20210126381A (en) * | 2020-04-10 | 2021-10-20 | 부산대학교 산학협력단 | A case for seismic wave observation equipment |
-
1987
- 1987-10-05 JP JP25131187A patent/JPH0194255A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7228724B2 (en) | 2002-10-17 | 2007-06-12 | Advanced Technology Materials, Inc. | Apparatus and process for sensing target gas species in semiconductor processing systems |
| US7296458B2 (en) | 2002-10-17 | 2007-11-20 | Advanced Technology Materials, Inc | Nickel-coated free-standing silicon carbide structure for sensing fluoro or halogen species in semiconductor processing systems, and processes of making and using same |
| US7475588B2 (en) * | 2002-10-17 | 2009-01-13 | Advanced Technology Materials, Inc. | Apparatus and process for sensing fluoro species in semiconductor processing systems |
| KR20210126381A (en) * | 2020-04-10 | 2021-10-20 | 부산대학교 산학협력단 | A case for seismic wave observation equipment |
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