JP2005077173A - Method and apparatus for sensing gas leak - Google Patents

Method and apparatus for sensing gas leak Download PDF

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JP2005077173A
JP2005077173A JP2003305983A JP2003305983A JP2005077173A JP 2005077173 A JP2005077173 A JP 2005077173A JP 2003305983 A JP2003305983 A JP 2003305983A JP 2003305983 A JP2003305983 A JP 2003305983A JP 2005077173 A JP2005077173 A JP 2005077173A
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gauge
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measuring device
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JP4078422B2 (en
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Atsushi Suzuki
淳 鈴木
Shingo Ichimura
信吾 一村
Akira Kurokawa
明 黒河
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National Institute of Advanced Industrial Science and Technology AIST
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple gas discrimination method using no heat source and not accompanying the reaction of gas itself to be sensed, that is, the consumption thereof, a leaked gas sensing method and a leaked gas sensing apparatus. <P>SOLUTION: In a case that the absolute pressure of the total pressure of a system is not changed or increased or decreased, the pressure of the system is measured by a pressure measuring instrument depending on a physical value and the decrease or increase change in the pressure of the system is sensed to sense the leak or mixing of a specific gas. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は漏洩ガス検出の方法及び装置に関するものであり、ある既知成分のガス中に他のガスが混入した場合にそのガス成分を識別するために、室温作動でき、また被検出ガスを反応、消費することなく熱源なしで検出する新しいタイプのガス検知方法とガスセンサに関する。   The present invention relates to a method and apparatus for detecting a leaked gas. When another gas is mixed in a gas having a certain known component, the gas component can be operated at room temperature to react with the detected gas. The present invention relates to a new type of gas detection method and gas sensor that detect without using a heat source without being consumed.

一般にイオン化やクロマトグラフを用いた質量分析法を行えば漏洩ガスを検出することが可能である。
その他のガス識別法として、様々なガスに対応したガスセンサを複数組み合わせることにより多成分を複数同時に識別しようとするもので、複数個のセンサーと各センサーからのシグナルを解析する情報処理装置からなるものが提案されている(特許文献1)。
また、クリスタルゲージ(水晶振動子)単体で、被測定ガスの高分子膜への吸着による粘性的性質の変化により共振抵抗値が変化することからクリスタルゲージの共振周波数変化と共振抵抗の変化の比を利用することによりガス識別を可能とその電気的インピーダンス変化と共振周波数変化の比を指標としそれぞれの値の組み合わせから成分を識別するガス識別センサーシステム(特許文献2)が提案されている。
また現在市販されているガスセンサとして、主流となっている半導体ガスセンサを含めたものに見られるように測定するガス自身を燃焼反応させることにより検出するものである(特許文献3)。このセンサは可燃性ガスと触媒材との触媒反応による発熱を、熱電変換効果により電圧信号に変換し、それを検出信号として検出するガス検出センサであって、被検出ガスと接触して触媒反応を起こす触媒材と、この反応による発熱から発生する局部的な温度差を電圧信号に変換する熱電変換材料膜を構成要素として含むことを特徴とする可燃性ガス検出センサである。
一方2成分とも既知である2成分混合気体の各濃度を測定する方法が開発されている(特許文献4)。この方法は物性値に敏感な圧力測定装置と、物性値に拠らない圧力測定装置で圧力を測定し、予め求めた物性値データに照らし合わせることによって2成分の各濃度を測定する方法である。この方法はガス成分の物性値に依存する圧力が成分によって異なることを基礎とした測定法である。
In general, leakage gas can be detected by performing mass spectrometry using ionization or chromatography.
Another gas identification method is to identify multiple components simultaneously by combining multiple gas sensors corresponding to various gases, and consists of multiple sensors and an information processing device that analyzes the signals from each sensor. Has been proposed (Patent Document 1).
In addition, since the resonance resistance value changes due to the change in the viscous properties due to the adsorption of the gas to be measured to the polymer film, the ratio of the change in the resonance frequency of the crystal gauge to the change in the resonance resistance. There has been proposed a gas identification sensor system (Patent Document 2) that makes it possible to identify a gas by using the above and identifies a component from a combination of each value using a ratio between a change in electrical impedance and a change in resonance frequency as an index.
Moreover, as a gas sensor currently marketed, it detects by carrying out the combustion reaction of the gas itself to be measured so that it may be seen including the mainstream semiconductor gas sensor (patent document 3). This sensor is a gas detection sensor that converts the heat generated by the catalytic reaction between the combustible gas and the catalyst material into a voltage signal by the thermoelectric conversion effect and detects it as a detection signal. And a thermoelectric conversion material film that converts a local temperature difference generated from heat generated by this reaction into a voltage signal, as a constituent element.
On the other hand, a method has been developed for measuring each concentration of a two-component gas mixture that is known for both components (Patent Document 4). This method is a method of measuring each concentration of two components by measuring pressure with a pressure measuring device sensitive to a physical property value and a pressure measuring device not depending on the physical property value, and comparing it with physical property value data obtained in advance. . This method is a measurement method based on the fact that the pressure depending on the physical property value of the gas component varies depending on the component.

特許第2888886号公報Japanese Patent No. 2888886 特許第2764109号公報Japanese Patent No. 2764109 特開2003−156461公報JP 2003-156461 A 特許第3336384号公報Japanese Patent No. 3336384

しかし上記の例のうち、まず質量分析法は汎用性が高く検出感度、識別能も高い分析法であるが、これを実際に行うには高価で大掛かりな装置が必要である。
また、ガスセンサを複数個用いる方法(特許文献1)では検出する成分にガスセンサを揃えることが必要であり、ガスセンサが対応していない成分については識別することができないという本質的な欠点を持つ。また、情報処理用の装置類を含めるとかなり大掛かりな装置となり、情報処理計算に時間を要するためにリアルタイムでの測定が不可能である。
一方、特許文献2の技術では常温ガス成分に対する識別が記載されておらず、また本発明で対象とするような混合気体への応用についての記載も示唆もない。
また、現在市販されているガスセンサの検知方法ではその検知過程においてガスの燃焼反応を伴うためガス検出の際には危険性が伴う。この検出法では測定に際し被検出ガスの消費を伴うため厳密にはある状況下での成分濃度を正確に測定することができない。さらにこの種のセンサは検出感度を確保するために加熱することが必要であり、こうした点も可燃性ガス検出には安全性の観点から好ましくない。
したがって、上記のいずれの技術においても、既知成分の気体中に別の未知気体成分が混入した場合、混入した気体の成分を識別することは不可能である。
本発明は上記の問題を解決するため、簡便で熱源を用いず、また被検出ガス自身の反応、すなわち消費を伴わないガス識別法及び漏洩ガス検知法を提供することを目的とする。
However, among the above examples, the mass spectrometry is an analysis method that is versatile and has high detection sensitivity and discrimination ability. However, an expensive and large-scale apparatus is required to actually perform this method.
Further, the method using a plurality of gas sensors (Patent Document 1) has an essential drawback that it is necessary to align gas sensors with the components to be detected, and components that are not supported by the gas sensors cannot be identified. In addition, if information processing devices are included, the device becomes quite large, and information processing calculation takes time, so real-time measurement is impossible.
On the other hand, in the technique of Patent Document 2, there is no description for the normal temperature gas component, and there is no description or suggestion about the application to the mixed gas as intended in the present invention.
Moreover, since the gas sensor detection method currently on the market involves a gas combustion reaction in the detection process, there is a risk in detecting the gas. Strictly speaking, this detection method involves consumption of the gas to be detected, so it is not possible to accurately measure the component concentration under certain circumstances. Further, this type of sensor needs to be heated in order to ensure detection sensitivity, and this is also not preferable for the detection of combustible gas from the viewpoint of safety.
Therefore, in any of the above-described techniques, when another unknown gas component is mixed in the known component gas, it is impossible to identify the mixed gas component.
In order to solve the above problems, an object of the present invention is to provide a gas identification method and a leakage gas detection method that are simple, do not use a heat source, and do not involve the reaction of the detected gas itself, that is, consumption.

本発明の上記の課題は、以下の手段により達成された。
(1)系の全圧の絶対圧力が変化しないかまたは増加もしくは減少する場合において、物性値に依存する圧力測定装置で系の圧力を測定し、その減少もしくは増加の変化を検知することによって、特定ガスの漏洩、混入を検知する方法。
(2)前記物性値は粘性とし、前記物性値に敏感な圧力測定装置として水晶摩擦真空計またはスピニングロータゲージを用い、物性値に影響を受けない圧力測定装置として隔膜真空計を用いた(1)記載の漏洩ガス検出方法。
(3)既知成分の気体中に別の未知1成分のガスが混入した際に物性値によらない絶対圧力計の増加または不変の出力に対して逆に圧力の減少の変化を示す物性値に敏感な圧力測定器の出力とを組み合わせることによって混入した気体漏洩を検知及び気体の成分を識別する方法。
(4)空気中に水素が漏洩混入した場合、絶対圧力真空計によって圧力の上昇または不変を検出すると同時に、該絶対圧力真空計と水素が増加したことによる粘性の低下を検出しうる、粘性に敏感な圧力計である水晶摩擦真空計、スピニングロータゲージ、もしくはその他の物性値に敏感な圧力測定子とを接続し、同時に圧力を測定して、両圧力測定値の変化の相違から空気中へ混入したガスの成分を識別する方法。
(5)大気中に水素またはヘリウムが漏洩した際に、大気圧センサと物性値に敏感な圧力測定装置の出力とを比較することにより水素またはヘリウムガスの漏洩を検知する方法。
(6)漏洩前後での変化を測定する物性値の影響を受けない圧力測定装置と、漏洩前後での変化を測定する物性値に敏感な圧力測定装置と上記のそれぞれの変化の相対変化を判定する回路からなる漏洩気体検知装置。
(7)微小な増加または不変化に対して減少の現象が起こった場合にそれを増幅して大きな変化として検出できる回路をさらに設けた(6)記載の漏洩気体検知装置。
(8)前記物性値に敏感な圧力測定装置として水晶摩擦真空計またはスピニングロータゲージを用い、物性値に影響を受けない圧力測定装置として隔膜真空計を用いた(6)記載の混合気体用の漏洩ガス検出装置。
(9)大気圧センサと、物性値に敏感な圧力測定装置と、両者の変化を比較する回路からなる、大気中への水素またはヘリウムガス漏洩検出装置。
The above object of the present invention has been achieved by the following means.
(1) When the absolute pressure of the total pressure of the system does not change or increases or decreases, by measuring the pressure of the system with a pressure measuring device depending on the physical property value and detecting the change of the decrease or increase, A method to detect leakage and contamination of specific gases.
(2) The physical property value is viscous, a quartz friction vacuum gauge or a spinning rotor gauge is used as a pressure measuring device sensitive to the physical property value, and a diaphragm vacuum gauge is used as a pressure measuring device not affected by the physical property value (1 ) Leakage gas detection method as described.
(3) When a gas of another unknown component is mixed in a gas of a known component, the physical property value indicates a change in pressure decrease with respect to an increase in the absolute pressure gauge or an unchanged output regardless of the physical property value. A method of detecting mixed gas leaks and identifying gas components by combining with the output of a sensitive pressure gauge.
(4) When hydrogen leaks into the air, the absolute pressure vacuum gauge detects an increase or no change in pressure, and at the same time it can detect a decrease in viscosity due to an increase in the absolute pressure vacuum gauge and hydrogen. Connect a sensitive pressure gauge, such as a quartz friction vacuum gauge, spinning rotor gauge, or other pressure gauge sensitive to physical properties, and measure the pressure at the same time. A method for identifying the components of mixed gases.
(5) A method of detecting leakage of hydrogen or helium gas by comparing an atmospheric pressure sensor and the output of a pressure measuring device sensitive to physical properties when hydrogen or helium leaks into the atmosphere.
(6) A pressure measuring device that is not affected by physical property values that measure changes before and after leakage, a pressure measuring device that is sensitive to physical property values that measure changes before and after leakage, and the relative change of each of the above changes Leakage gas detection device consisting of a circuit to perform.
(7) The leakage gas detection device according to (6), further comprising a circuit capable of amplifying the phenomenon when a decrease phenomenon occurs with respect to a minute increase or no change and detecting it as a large change.
(8) A quartz friction vacuum gauge or a spinning rotor gauge is used as a pressure measuring device sensitive to the physical property value, and a diaphragm vacuum gauge is used as a pressure measuring device not affected by the physical property value. Leakage gas detection device.
(9) A hydrogen or helium gas leak detection device into the atmosphere, comprising an atmospheric pressure sensor, a pressure measurement device sensitive to physical properties, and a circuit for comparing changes between the two.

本発明により既知成分気体に別の未知成分気体が混入した場合にその成分を識別することが可能になる。具体的には、例えば空気中への水素ガスの漏洩を検出することを可能にする。さらにこの検出法は熱源及び被測定対象の反応を伴わないため従来法と比べ安全に、かつ被測定対象を消費することなく検出できる方法である。また、この装置は小型化が可能なため携帯式の漏洩検知器としても応用できる。本発明は、とりわけ水素エネルギー関連の分野での利用が期待される。   According to the present invention, when another unknown component gas is mixed into the known component gas, the component can be identified. Specifically, for example, it is possible to detect leakage of hydrogen gas into the air. Furthermore, since this detection method does not involve the reaction of the heat source and the object to be measured, it can be detected more safely than the conventional method and without consuming the object to be measured. Moreover, since this apparatus can be reduced in size, it can be applied as a portable leak detector. The present invention is expected to be used particularly in the field related to hydrogen energy.

本発明は、系の絶対圧力が増加(減少)または不変の場合に粘性・熱伝導率・密度・分子量およびそれらの関数としての混合気体の物性値に依存する圧力が減少(もしくは増加)する現象を観測することによって漏洩した気体の成分を検知、識別するものである。
更に詳細には、粘性等の物性値に敏感な測定子Aと、絶対圧力のみに敏感な測定子Bを同時に用いて対象混合気体を計測し、測定子A、Bで測定した漏洩前後の圧力の変化を測定、比較することにより漏洩気体の検知、識別を行うものである。
本発明において、系の全圧の絶対圧力で変化しないかまたは増加する場合を例に述べると、これは例えば大気中や流れのある配管内のような、通常一定圧力にあり、かつ外からのガスの流入の可能性があるような状況下で、実際に気体が漏洩、混入した場合をいう。
In the present invention, when the absolute pressure of the system increases (decreases) or does not change, the pressure depending on the physical properties of the gas mixture as a function of viscosity, thermal conductivity, density, molecular weight, and the like decreases (or increases). Detecting and identifying the leaked gas component by observing.
In more detail, the target mixed gas is measured using the measuring element A sensitive to physical properties such as viscosity and the measuring element B sensitive only to absolute pressure, and the pressure before and after leakage measured by the measuring elements A and B is measured. The leakage gas is detected and identified by measuring and comparing these changes.
In the present invention, for example, when the absolute pressure of the total pressure of the system does not change or increases, this is usually at a constant pressure, for example, in the atmosphere or in a flowing pipe, and from the outside. This refers to the case where gas is actually leaked and mixed under the situation where there is a possibility of gas inflow.

物性値の差による漏洩気体識別については系の(物性値に依存しない)絶対圧力が変わらないか又は増加した場合、物性値と絶対圧力に依存する圧力測定装置で測定した系の圧力が減少したとすれば、その減少は絶対圧力によるものではないことから、減少の大きさに関わらず混合気体の物性値が変化したことによるものであることが帰結される。
例えば絶対圧力計で測定した大気の圧力が変化しないか増加した状態で水晶摩擦真空計で測定した圧力のみが減少した場合、その減少は水晶摩擦真空計が敏感に依存する物性である系の質量及び粘性等が大きく低下したことによるものであることが結論される。すなわち元々の構成気体である空気の質量及び粘性に比べて小さい気体が漏洩混入したことになる。この場合、後記の表1に見られるように空気に対してより小さい質量及び粘性を持つガスとしては水素、ヘリウム、窒素などがある。この場合、後述するように水素(またはヘリウム)を用いた場合は最小で2000ppmの濃度においてもここで用いた水晶摩擦真空計の最小変化である1Torr以上を観測することが可能であるため、漏洩気体が水素(またはヘリウム)であることは実際に識別できる。
For leaked gas identification based on the difference in physical properties, when the absolute pressure of the system (independent of the physical properties) does not change or increases, the pressure of the system measured by a pressure measuring device that depends on the physical properties and absolute pressure decreases. If this is the case, the decrease is not due to the absolute pressure, so that it can be attributed to the change in the physical property value of the gas mixture regardless of the magnitude of the decrease.
For example, if the atmospheric pressure measured with an absolute pressure gauge does not change or increases, but only the pressure measured with a quartz friction vacuum gauge decreases, the decrease is the mass of the system whose physical properties are sensitive to the quartz friction vacuum gauge. It is concluded that this is due to a significant decrease in viscosity and the like. That is, a gas that is smaller than the mass and viscosity of air, which is the original constituent gas, leaks and enters. In this case, as shown in Table 1 described later, gases having a smaller mass and viscosity than air include hydrogen, helium, and nitrogen. In this case, as described later, when hydrogen (or helium) is used, it is possible to observe 1 Torr or more, which is the minimum change of the quartz friction vacuum gauge used here even at a minimum concentration of 2000 ppm. It can actually be identified that the gas is hydrogen (or helium).

上記から容易に推測されるように逆に系の(物性値に依存しない)絶対圧力が変わらないかまたは減少した場合に物性値と絶対圧力に依存する圧力測定装置で測定した系の圧力が増加したとすれば、その増加は絶対圧力によるものではないことから、増加の大きさに関わらず混合気体の物性値が変化したことによるものであることが帰結される。   As can be easily guessed from the above, when the absolute pressure of the system (independent of the physical property value) does not change or decreases, the pressure of the system measured by a pressure measuring device that depends on the physical property value and absolute pressure increases. If so, the increase is not due to the absolute pressure, so that it is due to the change in the physical property value of the gas mixture regardless of the magnitude of the increase.

後述するように上記測定子Aと測定子Bに、測定子Aの対象圧力範囲以外に対応した感受性を有する測定子Cを追加することでさらに測定圧力範囲を広げる装置の感度を増幅することができる。
本発明における使用される測定子の例としては、例えば液柱差真空計、圧縮真空計、隔膜真空計、ブルドン管真空計等の圧力のみに敏感なものや、圧力に依存して変わると共に、運動固体が気体から受ける摩擦力変化・固体から気体への熱伝導率変化・固体表面近傍で気体が反応したときの固体が受ける分解生成熱といった物理量のうち、いずれかの物理量が変化する圧力計があげられる。
前記圧力が変化すると共に物理量が変化する圧力計としては、例えば粘性(摩擦)を利用する水晶摩擦真空計やスピニングロータゲージ、熱伝導を利用する熱電対真空計やピラニー真空計、そのほかクヌーセン真空計等を用いることができ、また、電離現象を利用する例えば熱陰極電離真空計、冷陰極電離真空計、放射線電離真空計等を使用することができる。これら測定子は、引火性・爆発性といった気体の性質・対象混合気体の濃度・圧力によって使い分けることができる。この圧力計は前記の測定子Aとして用いられる。
As described later, it is possible to amplify the sensitivity of the device that further expands the measurement pressure range by adding a measurement probe C having sensitivity corresponding to the measurement probe A other than the target pressure range of the measurement probe A to the measurement probe A and the measurement probe B. it can.
Examples of the probe used in the present invention include, for example, a liquid column differential vacuum gauge, a compression vacuum gauge, a diaphragm vacuum gauge, a Bourdon tube vacuum gauge and the like that are sensitive only to pressure, and change depending on the pressure, Pressure gauge that changes any of the physical quantities such as the frictional force that the moving solid receives from the gas, the change in thermal conductivity from the solid to the gas, and the heat of decomposition generated by the solid when the gas reacts near the solid surface Is given.
Examples of pressure gauges that change in physical quantity as the pressure changes include quartz friction vacuum gauges and spinning rotor gauges that use viscosity (friction), thermocouple vacuum gauges and Pirani vacuum gauges that use heat conduction, and other Knudsen vacuum gauges. In addition, for example, a hot cathode ionization vacuum gauge, a cold cathode ionization vacuum gauge, a radiation ionization vacuum gauge, or the like using an ionization phenomenon can be used. These probes can be used properly depending on the gas properties such as flammability and explosiveness, the concentration and pressure of the target mixed gas. This pressure gauge is used as the measuring element A.

次に本発明の好ましい実施態様を図面に従って説明する。
なお図面中、同符号は同じものを示す。
Next, preferred embodiments of the present invention will be described with reference to the drawings.
In the drawings, the same symbols indicate the same items.

図1に本発明を実施する装置の模式図を示す。同図に示されるように、被測定混合ガスが供給される配管4に連通管10を接続し、この連通管に対して混合ガスの粘性や分子密度等の物性によって測定値が変化しない絶対圧力を測定することができる絶対圧力測定子1を接続すると共に、気体の粘度等の物性により表示圧力が変化し、且つ予めその特性が知られている圧力測定子、即ち圧力・物性値測定子2を接続している。
また、前記絶対圧力測定子1及び圧力・物性測定子2で測定した漏洩前後の圧力変化から特定の気体漏洩を判断する気体成分識別(気体漏洩検知)装置3を備えている。
FIG. 1 shows a schematic diagram of an apparatus for carrying out the present invention. As shown in the figure, a communication pipe 10 is connected to a pipe 4 to which a mixed gas to be measured is supplied, and an absolute pressure at which the measured value does not change due to physical properties such as the viscosity and molecular density of the mixed gas with respect to this communication pipe. Is connected to an absolute pressure measuring element 1, and a pressure measuring element whose display pressure changes depending on physical properties such as gas viscosity and whose characteristics are known in advance, that is, a pressure / physical property measuring element 2 Is connected.
Further, a gas component identification (gas leakage detection) device 3 is provided for judging a specific gas leakage from pressure changes before and after leakage measured by the absolute pressure gauge 1 and the pressure / physical property gauge 2.

図2により具体的な実施態様を示す。図2は、空気中に水素ガスが混入した場合の水素検知装置の実施例であり、絶対圧力測定子として隔膜真空計5を用いている。この隔膜真空計5は物性値に無関係に気体圧力の絶対値を得ることができ、それにより気体の種別に無関係に漏洩前後の気体圧力を計測することができる。図中8は被測定混合ガスが供給される配管であり、7は気体成分識別装置である。   A specific embodiment is shown in FIG. FIG. 2 shows an embodiment of a hydrogen detector when hydrogen gas is mixed in the air, and a diaphragm vacuum gauge 5 is used as an absolute pressure gauge. The diaphragm vacuum gauge 5 can obtain the absolute value of the gas pressure regardless of the physical property value, and can thereby measure the gas pressure before and after the leakage regardless of the type of gas. In the figure, 8 is a pipe to which a mixed gas to be measured is supplied, and 7 is a gas component identification device.

図2の態様において、圧力・物性値測定子としては水晶摩擦真空計6を用いている。
この水晶摩擦真空計6の特性を図3に示す。これは例えば表1に示すように気体の分子量と粘性係数の違いによって水晶摩擦真空計の指示値が見かけ上異なる圧力を表示していることを示すものである。この理由は、水晶摩擦真空計が、気体に接した水晶振動子の受ける気体との摩擦力が、圧力が粘性流の領域では気体の分子量と気体の粘性係数の積の1/2乗に比例することから生じるものである。この水晶摩擦真空計は、常温で動作し、被測定気体を反応させることがないため測定によって被反応気体を消費せず、可燃性ガスを安全に検出、測定することが可能である。
In the embodiment of FIG. 2, a quartz friction vacuum gauge 6 is used as a pressure / physical property value measuring element.
The characteristics of this quartz friction vacuum gauge 6 are shown in FIG. This indicates that, as shown in Table 1, for example, the indicated value of the quartz friction vacuum gauge is different depending on the difference in gas molecular weight and viscosity coefficient. This is because the friction force between the quartz friction vacuum gauge and the gas received by the quartz crystal in contact with the gas is proportional to the 1/2 power of the product of the molecular weight of the gas and the viscosity coefficient of the gas in the viscous flow region. It is a result of doing. Since this quartz friction vacuum gauge operates at room temperature and does not react with the gas to be measured, it does not consume the gas to be measured by the measurement and can detect and measure the combustible gas safely.

Figure 2005077173
Figure 2005077173

特に測定子5の増加に対して測定子6の変化が逆に減少するような場合はその相対変化が大きく結果としてその変化が検出しやすくなるため、ガス識別を有効に行うことができる。このような例として、空気中への水素及びヘリウムの漏出がある。   In particular, when the change of the probe 6 decreases conversely with the increase of the probe 5, the relative change is large and the change is easily detected as a result, so that the gas identification can be performed effectively. An example of this is leakage of hydrogen and helium into the air.

図4は、図3の装置を用い、上記によって示された検出の例である。圧力のみに敏感な隔膜真空計5と圧力と例えば粘性等の物性値に敏感な水晶摩擦真空計6とで測定されている系において、空気中に他の未知成分ガスが混入した場合に隔膜真空計5の測定値aは混入した分増加するが、水晶摩擦真空計6の測定値bは混合気体の物性値に応じてその変化量の割合は隔膜真空計5の変化量と比べて異なる値を示し、減少する結果を示した。
水晶摩擦真空計は測定対象の質量及び粘性に大きく依存することから、この場合空気中に空気と比較して質量または粘性の小さいガス、すなわち水素(またはヘリウム)が混入したことがわかる。
なお、ヘリウムの場合も同様な変化を検出した。
FIG. 4 is an example of the detection shown above using the apparatus of FIG. In a system in which a diaphragm vacuum gauge 5 sensitive only to pressure and a quartz friction vacuum gauge 6 sensitive to physical properties such as viscosity are measured, a diaphragm vacuum is generated when other unknown component gas is mixed in the air. The measured value a of the total 5 increases by the amount of contamination, but the measured value b of the quartz friction vacuum gauge 6 is different from the change amount of the diaphragm vacuum gauge 5 according to the physical property value of the mixed gas. And decreased results.
Since the quartz friction vacuum gauge greatly depends on the mass and viscosity of the object to be measured, it can be understood that in this case, a gas having a smaller mass or viscosity than that of air, that is, hydrogen (or helium) is mixed in the air.
Similar changes were detected in the case of helium.

時間応答特性については、水晶摩擦真空計の最大変化の90%までの立ち上がり時間は200秒程度であったが、この時間にはガス流れの飽和に要する時間が含まれているため、実際の応答時間はより短い。また最大変化の90%までの立ち下がり時間も100秒程度であったが、この場合もここでの実施上水素ガスが完全に排出されるまでの時間が含まれているため実際の応答時間はこれよりも短い。本発明のガス漏洩検知方法は以上のような時間応答特性を持つため繰り返し特性において優れた方法である。
さらに本発明の方法では、濃度計算機と組み合わせて前述した「2種類混合気体の濃度測定方法および濃度測定装置(特許第3336384号)」の方法を用いることにより検知したガスの濃度が定量できる。
Regarding the time response characteristics, the rise time up to 90% of the maximum change of the quartz friction vacuum gauge was about 200 seconds, but this time includes the time required for saturation of the gas flow. The time is shorter. Also, the fall time to 90% of the maximum change was about 100 seconds, but in this case as well, the actual response time is Shorter than this. Since the gas leakage detection method of the present invention has the time response characteristics as described above, it is an excellent method in repetition characteristics.
Further, in the method of the present invention, the concentration of the detected gas can be quantified by using the method of “concentration measuring method and concentration measuring apparatus (Japanese Patent No. 3336384)” described above in combination with a concentration calculator.

図5は、本発明の変更実施態様を示し、前記図2に示す実施態様の装置に、更に配管15の連通管にスピニングロータゲージ13を接続し、3種類の真空計で構成された濃度計測装置の実施例を示す。隔膜式真空計11は前記のように気体の種別に無関係に絶対圧力を計測し、水晶摩擦真空計12は気体の粘性・分子量の物性値と圧力の双方に敏感であって使用圧力範囲は10−2pa から10−5pa であり、スピニングロータゲージ13は水晶摩擦真空計12と同様に気体の粘性・分子量の物性値と圧力の双方に敏感であって、使用圧力範囲は10−5Pa から1Pa である。識別結果は気体成分識別装置14より得られる。 FIG. 5 shows a modified embodiment of the present invention, in which the spinning rotor gauge 13 is further connected to the communication pipe of the pipe 15 in the apparatus of the embodiment shown in FIG. 2, and the concentration measurement is made up of three types of vacuum gauges. An embodiment of the apparatus is shown. As described above, the diaphragm type vacuum gauge 11 measures the absolute pressure regardless of the type of gas, and the quartz friction vacuum gauge 12 is sensitive to both the physical properties of the viscosity and molecular weight of the gas and the pressure. −2 pa to 10 −5 pa, and the spinning rotor gauge 13 is sensitive to both the viscosity and molecular weight physical properties and pressure of the gas, like the quartz friction vacuum gauge 12, and the operating pressure range is 10 −5 Pa. To 1 Pa. The identification result is obtained from the gas component identification device 14.

図6には前記スピニングロータゲージ13の特性を示しており、この測定子は水晶摩擦真空計よりも真空度の高い領域を計測できる。同図に見られるように大気圧以上の圧力領域ではスピニングローターでの指示値において空気と水素の差は少なくとも2倍はあるため、その差から推測して水素ガス識別が可能である。
したがって、図5の気体成分識別装置14においては、真空度の高い領域ではスピニングロータゲージ13の表示値を用い、低い領域では水晶摩擦真空計12の表示値に基づくことにより漏洩気体の識別を行うことができ、また、両者の値の有効な範囲では両者の値を用い、圧力の影響を演算処理して取り除くことで、気体の物性値を得ることにより漏洩気体の識別を行うことができる。
FIG. 6 shows the characteristics of the spinning rotor gauge 13. This probe can measure a region having a higher degree of vacuum than the quartz friction vacuum gauge. As seen in the figure, the difference between air and hydrogen is at least twice in the indicated value at the spinning rotor in the pressure region above the atmospheric pressure, so that the hydrogen gas can be identified by inferring from the difference.
Therefore, in the gas component identification device 14 of FIG. 5, the leaked gas is identified by using the display value of the spinning rotor gauge 13 in the high vacuum region and based on the display value of the quartz friction vacuum gauge 12 in the low region. In addition, it is possible to identify the leaked gas by obtaining the physical property value of the gas by using both values in the effective range of both values and removing the influence of the pressure by performing arithmetic processing.

本発明の装置を模式的に説明する測定機器構成図である。It is a measuring device block diagram which illustrates the apparatus of this invention typically. 本発明の実施例の測定機器構成図である。It is a measuring device block diagram of the Example of this invention. 本発明の実施例で用いる水晶摩擦真空計の特性を示すグラフである。It is a graph which shows the characteristic of the quartz friction vacuum gauge used in the Example of this invention. 空気中に水素ガスが漏洩した場合の測定結果を示すグラフである。It is a graph which shows the measurement result when hydrogen gas leaks in the air. 本発明の別の実施例の測定機器構成図である。It is a measuring device block diagram of another Example of this invention. 本発明の実施例で用いるスピニングロータゲージの特性図である。It is a characteristic view of the spinning rotor gauge used in the embodiment of the present invention.

符号の説明Explanation of symbols

1 絶対圧力測定子
2 圧力・物性測定子
3 気体成分識別(気体漏洩検知)装置
4 配管
5 隔膜真空計
6 水晶摩擦真空計
7 気体成分識別装置
8 配管
10 連通管
11 隔膜式真空計
12 水晶摩擦真空計
13 スピニングロータゲージ
14 気体成分識別装置
DESCRIPTION OF SYMBOLS 1 Absolute pressure measuring element 2 Pressure / physical property measuring element 3 Gas component identification (gas leak detection) device 4 Piping 5 Diaphragm vacuum gauge 6 Quartz friction vacuum gauge 7 Gas component discriminating device 8 Piping 10 Communication pipe 11 Diaphragm type vacuum gauge 12 Quartz friction Vacuum gauge 13 Spinning rotor gauge 14 Gas component identification device

Claims (9)

系の全圧の絶対圧力が変化しないかまたは増加もしくは減少する場合において、物性値に依存する圧力測定装置で系の圧力を測定し、その減少もしくは増加の変化を検知することによって、特定ガスの漏洩、混入を検知する方法。   When the absolute pressure of the total pressure of the system does not change or increases or decreases, the pressure of the system is measured by a pressure measuring device that depends on the physical property value, and the change in the specific gas is detected by detecting the change in the decrease or increase. A method to detect leakage and contamination. 前記物性値は粘性とし、前記物性値に敏感な圧力測定装置として水晶摩擦真空計またはスピニングロータゲージを用い、物性値に影響を受けない圧力測定装置として隔膜真空計を用いた請求項1記載の漏洩ガス検出方法。   The physical property value is viscosity, a quartz friction vacuum gauge or a spinning rotor gauge is used as a pressure measuring device sensitive to the physical property value, and a diaphragm vacuum gauge is used as a pressure measuring device not affected by the physical property value. Leakage gas detection method. 既知成分の気体中に別の未知1成分のガスが混入した際に物性値によらない絶対圧力計の増加または不変の出力に対して逆に圧力の減少の変化を示す物性値に敏感な圧力測定器の出力とを組み合わせることによって混入した気体漏洩を検知及び気体の成分を識別する方法。   Pressure sensitive to a physical property value that shows a change in pressure decrease against an increase or an invariant output of an absolute pressure gauge that does not depend on the physical property value when another unknown one component gas is mixed in a known component gas A method for detecting mixed gas leakage and identifying gas components by combining with the output of a measuring device. 空気中に水素が漏洩混入した場合、絶対圧力真空計によって圧力の上昇または不変を検出すると同時に、該絶対圧力真空計と水素が増加したことによる粘性の低下を検出しうる、粘性に敏感な圧力計である水晶摩擦真空計、スピニングロータゲージ、もしくはその他の物性値に敏感な圧力測定子とを接続し、同時に圧力を測定して、両圧力測定値の変化の相違から空気中へ混入したガスの成分を識別する方法。   Pressure that is sensitive to viscosity that can detect a rise or no change in pressure with an absolute pressure gauge when hydrogen leaks into the air, and at the same time, a decrease in viscosity due to an increase in the absolute pressure gauge and hydrogen. Connected to a quartz friction vacuum gauge, spinning rotor gauge, or other pressure gauge sensitive to physical properties, and simultaneously measured the pressure, gas mixed into the air due to the difference in both pressure measurements To identify the components of 大気中に水素またはヘリウムが漏洩した際に、大気圧センサと物性値に敏感な圧力測定装置の出力とを比較することにより水素またはヘリウムガスの漏洩を検知する方法。   A method for detecting leakage of hydrogen or helium gas by comparing the atmospheric pressure sensor and the output of a pressure measuring device sensitive to physical properties when hydrogen or helium leaks into the atmosphere. 漏洩前後での変化を測定する物性値の影響を受けない圧力測定装置と、漏洩前後での変化を測定する物性値に敏感な圧力測定装置と上記のそれぞれの変化の相対変化を判定する回路からなる漏洩気体検知装置。   From a pressure measuring device that is not affected by physical property values that measure changes before and after leakage, a pressure measuring device that is sensitive to physical property values that measure changes before and after leakage, and a circuit that determines the relative changes of each of the above changes A leaking gas detection device. 微小な増加または不変化に対して減少の現象が起こった場合にそれを増幅して大きな変化として検出できる回路をさらに設けた請求項6記載の漏洩気体検知装置。   7. The leaked gas detection device according to claim 6, further comprising a circuit that amplifies the phenomenon when a decrease phenomenon occurs with respect to a minute increase or no change and detects it as a large change. 前記物性値に敏感な圧力測定装置として水晶摩擦真空計またはスピニングロータゲージを用い、物性値に影響を受けない圧力測定装置として隔膜真空計を用いた請求項6記載の混合気体用の漏洩ガス検出装置。   7. A leak gas detection for a mixed gas according to claim 6, wherein a quartz friction vacuum gauge or a spinning rotor gauge is used as the pressure measuring device sensitive to the physical property value, and a diaphragm vacuum gauge is used as the pressure measuring device not affected by the physical property value. apparatus. 大気圧センサと、物性値に敏感な圧力測定装置と、両者の変化を比較する回路からなる、大気中への水素またはヘリウムガス漏洩検出装置。
A hydrogen or helium gas leak detection device into the atmosphere, comprising an atmospheric pressure sensor, a pressure measurement device sensitive to physical properties, and a circuit that compares changes in both.
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Cited By (6)

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JP2009059483A (en) * 2007-08-30 2009-03-19 National Institute Of Advanced Industrial & Technology Method and apparatus for measuring variation in plasma component
JP2009115760A (en) * 2007-11-09 2009-05-28 National Institute Of Advanced Industrial & Technology Method and device for measuring concentration
JP2010038867A (en) * 2008-08-08 2010-02-18 National Institute Of Advanced Industrial & Technology Device and method for measuring supply gas decomposition rate of plasma system
JP2016170072A (en) * 2015-03-13 2016-09-23 Vista株式会社 Evacuation monitoring device
CN108414414A (en) * 2017-12-15 2018-08-17 南京利德东方橡塑科技有限公司 Resistance to combustion gas permeability experimental rig
US11335575B2 (en) 2017-08-25 2022-05-17 Inficon, Inc. Unconsumed precursor monitoring

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009059483A (en) * 2007-08-30 2009-03-19 National Institute Of Advanced Industrial & Technology Method and apparatus for measuring variation in plasma component
JP2009115760A (en) * 2007-11-09 2009-05-28 National Institute Of Advanced Industrial & Technology Method and device for measuring concentration
JP2010038867A (en) * 2008-08-08 2010-02-18 National Institute Of Advanced Industrial & Technology Device and method for measuring supply gas decomposition rate of plasma system
JP2016170072A (en) * 2015-03-13 2016-09-23 Vista株式会社 Evacuation monitoring device
US11335575B2 (en) 2017-08-25 2022-05-17 Inficon, Inc. Unconsumed precursor monitoring
US11929270B2 (en) 2017-08-25 2024-03-12 Inficon, Inc. Unconsumed precursor monitoring
CN108414414A (en) * 2017-12-15 2018-08-17 南京利德东方橡塑科技有限公司 Resistance to combustion gas permeability experimental rig
CN108414414B (en) * 2017-12-15 2023-09-22 南京利德东方橡塑科技有限公司 Gas permeation resistance test device

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