JP2005069820A - Electrochemical gas detector - Google Patents

Electrochemical gas detector Download PDF

Info

Publication number
JP2005069820A
JP2005069820A JP2003298771A JP2003298771A JP2005069820A JP 2005069820 A JP2005069820 A JP 2005069820A JP 2003298771 A JP2003298771 A JP 2003298771A JP 2003298771 A JP2003298771 A JP 2003298771A JP 2005069820 A JP2005069820 A JP 2005069820A
Authority
JP
Japan
Prior art keywords
gas
electrochemical
concentration
gas detector
detected
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
JP2003298771A
Other languages
Japanese (ja)
Other versions
JP4458795B2 (en
Inventor
Hiroyuki Matsuda
裕之 松田
Toru Ishichi
徹 石地
Atsushi Ichikawa
敦史 市川
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.)
Riken Keiki KK
Original Assignee
Riken Keiki KK
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 Riken Keiki KK filed Critical Riken Keiki KK
Priority to JP2003298771A priority Critical patent/JP4458795B2/en
Publication of JP2005069820A publication Critical patent/JP2005069820A/en
Application granted granted Critical
Publication of JP4458795B2 publication Critical patent/JP4458795B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Landscapes

  • Measuring Oxygen Concentration In Cells (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrochemical gas detector capable of detecting gas with high reliability over a long period of time. <P>SOLUTION: This electrochemical gas detector is equipped with an electrochemical sensor and constituted so as to detect the concentration of the gas to be detected on the basis of the output value from the electrochemical sensor. The electrochemical gas detector is also equipped with an indication value correcting means for performing correction so as to increase the indication value of the concentration of the gas to be detected to the output value from the electrochemical sensor with the elapse of time and the gas to be detected is preferably a carbon monoxide gas. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、電気化学式ガス検知器に関する。   The present invention relates to an electrochemical gas detector.

一酸化炭素ガスを検知するためのガス検知器としては、例えば定電位電解式ガスセンサ、ガルバニ電池式ガスセンサなどの電気化学式ガスセンサを備えてなるものが知られている(例えば、特許文献1〜特許文献3参照。)。   As a gas detector for detecting carbon monoxide gas, a gas detector including an electrochemical gas sensor such as a constant potential electrolysis gas sensor or a galvanic cell gas sensor is known (for example, Patent Document 1 to Patent Document). 3).

電気化学式ガスセンサの或る種のものとしては、例えば電解液を収容するための電解液収容用空間を形成し、ガス透過性を有する多孔質シートによって塞がれる2つの開口を有する電解液用セルと、一方の多孔質シートの表面に設けられ、検知対象ガスである一酸化炭素ガスを電気分解させるための作用極と、他方の多孔質シートに設けられ、作用極に対する対極と、当該他方の多孔質シートに対極と分離して設けられ、作用極の電位を制御するための参照極とを備えてなる定電位電解式ガスセンサが用いられている。   As a certain type of electrochemical gas sensor, for example, an electrolyte cell having an opening for accommodating an electrolyte solution and having two openings that are closed by a porous sheet having gas permeability And a working electrode provided on the surface of one porous sheet for electrolyzing carbon monoxide gas as a detection target gas, provided on the other porous sheet, a counter electrode for the working electrode, and the other A constant potential electrolytic gas sensor is used which is provided on a porous sheet separately from a counter electrode and includes a reference electrode for controlling the potential of the working electrode.

このような多孔質シート、電極、電解液および電解液用セルを構成要素とする電気化学式ガスセンサは、作用極、対極および参照極が電解液に浸された状態において、当該作用極において検知対象ガスが電気分解されることにより、この作用極および対極に生じる電気化学反応に起因して発生する電解電流値によって示される出力値の大きさと、検知対象ガス濃度とが比例関係にあることを利用し、出力値を測定することによって検知対象ガス濃度を検知するものである。   Such an electrochemical gas sensor including a porous sheet, an electrode, an electrolytic solution, and an electrolytic cell as a constituent element is a gas to be detected at the working electrode in a state where the working electrode, the counter electrode, and the reference electrode are immersed in the electrolytic solution. As a result of the electrolysis, the output value indicated by the electrolytic current value generated due to the electrochemical reaction occurring at the working electrode and the counter electrode is proportional to the concentration of the gas to be detected. The detection target gas concentration is detected by measuring the output value.

しかしながら、電気化学式ガス検知器においては、電気化学式ガスセンサが、例えば多孔質シートの汚れ、電極を構成する金属の酸化、電解液の触媒作用の劣化などに起因する経時的な特性変化が大きく、そのため、使用時間が大きくなるに従って出力値にバラツキが生じてガス検出性能が低下してしまうため、ガス濃度検知性能が次第に低下してしまう、という問題がある。
このような電気化学式ガス検知器におけるガス濃度検知性能低下の問題は、例えば自動車道のトンネル内などの劣悪な環境下において用いられた場合に、電気化学式ガス検知器の稼働を開始した初期期間において顕著なものとなる。
However, in the electrochemical gas detector, the electrochemical gas sensor has a large characteristic change over time due to, for example, contamination of the porous sheet, oxidation of the metal constituting the electrode, deterioration of the catalytic action of the electrolytic solution, etc. As the usage time increases, the output value varies and the gas detection performance is lowered. Therefore, there is a problem that the gas concentration detection performance is gradually lowered.
The problem of the gas concentration detection performance degradation in such an electrochemical gas detector is, for example, when it is used in a poor environment such as in a tunnel on a motorway, during the initial period when the electrochemical gas detector starts operation. It will be remarkable.

特開平05−119020号公報Japanese Patent Laid-Open No. 05-11020 特開平05−223777号公報Japanese Patent Laid-Open No. 05-223777 特開平06−058906号公報Japanese Patent Laid-Open No. 06-058906

本発明は以上のような事情に基づいてなされたものであって、その目的は、信頼性の高いガス検知を長期間にわたって行うことのできる電気化学式ガス検知器を提供することにある。   The present invention has been made based on the above circumstances, and an object thereof is to provide an electrochemical gas detector capable of performing gas detection with high reliability over a long period of time.

本発明の電気化学式ガス検知器は、電気化学式センサを備え、当該電気化学式センサからの出力値に基づいて検知対象ガス濃度を検知する電気化学式ガス検知器であって、
電気化学式センサからの出力値に対する検知対象ガス濃度の指示値を経時的に増加する補正を行う指示値補正手段を備えていることを特徴とする。
The electrochemical gas detector of the present invention is an electrochemical gas detector that includes an electrochemical sensor and detects a detection target gas concentration based on an output value from the electrochemical sensor,
The apparatus is characterized by comprising an instruction value correcting means for correcting the instruction value of the detection target gas concentration with respect to the output value from the electrochemical sensor to increase with time.

本発明の電気化学式ガス検知器においては、検知対象ガスが一酸化炭素ガスであることが好ましい。   In the electrochemical gas detector of the present invention, the detection target gas is preferably carbon monoxide gas.

本発明の電気化学式ガス検知器は、指示値補正手段が、使用初期期間経過後は、使用初期期間の補正率より小さい補正率で補正を行うものであることが好ましい。   In the electrochemical gas detector of the present invention, it is preferable that the indicated value correcting means corrects at a correction rate smaller than the correction rate of the initial use period after the initial use period has elapsed.

本発明の電気化学式ガス検知器は、自動車道のトンネル内における検知対象ガス濃度の検知に好適に用いられる。
このような場合においては、検知された検知対象ガス濃度を、トンネル内の排気機構の制御に用いることができる。
The electrochemical gas detector of the present invention is suitably used for detecting the concentration of a gas to be detected in a tunnel on an automobile road.
In such a case, the detected gas concentration to be detected can be used for controlling the exhaust mechanism in the tunnel.

本発明の電気化学式ガス検知器によれば、検知対象ガス濃度の指示値を補正する指示値補正手段が設けられており、この指示値補正手段によって、電気化学式ガスセンサにおいて経時的に生じるガス検出性能の低下を、その程度に応じて当該電気化学式ガスセンサの出力値に対する検知対象ガス濃度の指示値が大きくなるよう補正して補償することができるため、電気化学式ガスセンサに経時的な特性変化が生じても、検知対象ガス濃度の指示値においてガス濃度検知性能が低下することが抑制されることから、結果として、信頼性の高いガス検知を長期間にわたって行うことができる。   According to the electrochemical gas detector of the present invention, the indicated value correcting means for correcting the indicated value of the gas concentration to be detected is provided, and the detected gas performance that occurs over time in the electrochemical gas sensor by this indicated value correcting means. Can be compensated by increasing the indicated value of the gas concentration to be detected with respect to the output value of the electrochemical gas sensor according to the degree of the decrease, and therefore, the characteristic change with time of the electrochemical gas sensor occurs. However, since the gas concentration detection performance is prevented from being lowered at the indicated value of the detection target gas concentration, as a result, highly reliable gas detection can be performed over a long period of time.

以下、本発明の実施の形態について詳細に説明する。
図1は、本発明の電気化学式ガス検知器の構成の一例を示す説明図である。
この電気化学式ガス検知器10は、電気化学式ガスセンサとして定電位電解式ガスセンサを用いてなるものであって、検査対象のガス(以下、「被検査ガス」ともいう。)を導入するためのガス導入口13Aおよびガス排出口13Bを有するガス用セル13と、当該ガス用セル13に連結された定電位電解式ガスセンサ20と、当該定電位電解式ガスセンサ20を作動させるための制御部(図示せず)とにより構成されているガス検知器本体11を備えている。
Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is an explanatory diagram showing an example of the configuration of the electrochemical gas detector of the present invention.
The electrochemical gas detector 10 uses a constant potential electrolytic gas sensor as an electrochemical gas sensor, and introduces a gas for introducing a gas to be inspected (hereinafter also referred to as “inspected gas”). A gas cell 13 having a port 13A and a gas discharge port 13B, a constant potential electrolytic gas sensor 20 connected to the gas cell 13, and a control unit (not shown) for operating the constant potential electrolytic gas sensor 20 The gas detector main body 11 comprised by these is provided.

そして、電気化学式ガス検知器10には、ガス検知器本体11における定電位電解式ガスセンサ20からの出力値に対する検知対象ガス濃度の指示値を経時的に増加する補正を行う指示値補正手段(図示せず)が設けられている。
ここに、「指示値」とは、定電位電解式ガスセンサ20からの出力値の大きさと、検知対象ガス濃度とが比例関係にあることを利用して、当該出力値の大きさに基づいて定められる、検知対象ガスの濃度を示す値である。
この図の例においては、定電位電解式ガスセンサ20の出力値に対する検知対象ガス濃度の指示値の初期値が制御部に記録されている。
Then, the electrochemical gas detector 10 includes an instruction value correction means for correcting the instruction value of the gas concentration to be detected with respect to the output value from the constant potential electrolysis gas sensor 20 in the gas detector body 11 to increase with time (FIG. Not shown).
Here, the “indicated value” is determined based on the magnitude of the output value using the fact that the magnitude of the output value from the constant potential electrolytic gas sensor 20 and the concentration of the detection target gas are in a proportional relationship. Is a value indicating the concentration of the detection target gas.
In the example of this figure, the initial value of the indication value of the detection target gas concentration with respect to the output value of the constant potential electrolytic gas sensor 20 is recorded in the control unit.

定電位電解式ガスセンサ20は、硫酸水溶液よりなる電解液を収容するための電解液収容空間21Aを形成し、外方に伸びる円筒状の連結用部材22が設けられた第1の開口23と、当該第1の開口23と対向する位置に設けられた円状の第2の開口24とを有する、例えばポリカーボネート、塩化ビニルなどよりなる電解液用セル21を備えてなり、当該電解液用セル21の第1の開口23に適合する大きさを有し、この第1の開口23を塞ぐよう設けられた、電解液を透過させない第1のガス透過膜31と、当該第1のガス透過膜31の電解液収容空間21Aに臨む表面に形成された、検知対象ガスを電気分解させるための作用極34と、第2の開口24に適合する大きさを有し、この第2の開口24を塞ぐよう設けられた、電解液を透過させない第2のガス透過膜32と、当該第2のガス透過膜32の電解液収容空間21Aに臨む表面に形成された、作用極34に対する対極35およびこの対極35と分離して設けられた作用極34の電位を制御するための参照極36とを備えてなるものである。
この図の例において、21Bは、電解液用セル21内部の圧力を調整するための開口である。
The constant potential electrolytic gas sensor 20 forms an electrolytic solution housing space 21A for containing an electrolytic solution made of an aqueous sulfuric acid solution, and includes a first opening 23 provided with a cylindrical connecting member 22 extending outwardly, An electrolyte solution cell 21 made of, for example, polycarbonate, vinyl chloride or the like, having a circular second opening 24 provided at a position facing the first opening 23, is provided. A first gas permeable film 31 that has a size suitable for the first opening 23 and is provided so as to close the first opening 23 and that does not allow the electrolyte solution to pass therethrough, and the first gas permeable film 31. The working electrode 34 for electrolyzing the gas to be detected, which is formed on the surface facing the electrolytic solution containing space 21 </ b> A, has a size suitable for the second opening 24, and closes the second opening 24. The electrolyte solution The second gas permeable membrane 32 that is not to be made, and the counter electrode 35 that is formed on the surface of the second gas permeable membrane 32 that faces the electrolytic solution housing space 21A, and the action that is provided separately from the counter electrode 35. A reference pole 36 for controlling the potential of the pole 34 is provided.
In the example of this figure, 21B is an opening for adjusting the pressure inside the electrolyte cell 21.

定電位電解式ガスセンサ20においては、作用極34および参照極36は、例えばポテンショスタット回路39に接続されており、このポテンショスタット回路39には、抵抗Rを介して対極35も接続されている。   In the constant potential electrolytic gas sensor 20, the working electrode 34 and the reference electrode 36 are connected to, for example, a potentiostat circuit 39, and a counter electrode 35 is also connected to the potentiostat circuit 39 via a resistor R.

定電位電解式ガスセンサ20において、作用極34、対極35および参照極36としては、例えば白金、金、銀、銅、ルテニウム、酸化ルテニウムまたはそれらの混合物などの電極用材料金属よりなる電極を用いることができる。
また、第1のガス透過膜31および第2のガス透過膜32の各々としては、例えばポリテトラフルオロエチレン樹脂(PTFE樹脂)製などの多孔質シートを用いることができる。
In the potentiostatic gas sensor 20, as the working electrode 34, the counter electrode 35, and the reference electrode 36, an electrode made of an electrode material metal such as platinum, gold, silver, copper, ruthenium, ruthenium oxide, or a mixture thereof is used. Can do.
Moreover, as each of the 1st gas permeable film 31 and the 2nd gas permeable film 32, porous sheets, such as a product made from polytetrafluoroethylene resin (PTFE resin), can be used, for example.

指示値補正手段としては、例えばマイクロコンピューターなどを用いることができる。   As the instruction value correcting means, for example, a microcomputer can be used.

指示値補正手段による補正は、電気化学式ガス検知器10が用いられる環境条件などに応じて適宜の態様とすることができ、例えば定電位電解式ガスセンサ20からの出力値に対する検知対象ガス濃度の指示値を、経時的な変化に伴って段階的に増大させるものであっても、傾斜的に増大させるものであってもよい。   The correction by the indicated value correcting means can be in an appropriate mode according to the environmental conditions in which the electrochemical gas detector 10 is used. For example, an indication of the detection target gas concentration with respect to the output value from the constant potential electrolytic gas sensor 20 The value may be increased stepwise as the time changes, or may be increased gradually.

指示値補正手段による補正の好ましい態様としては、使用初期期間経過後の補正率を、使用初期期間の補正率より小さくする。
ここに、「使用初期期間」とは、定電位電解式ガスセンサ20などの電気化学式ガスセンサ自体の有する劣化特性から経時的な特性変化が極めて大きい期間を示し、具体的には、例えば2カ月間である。
また、この使用初期期間は、定電位電解式ガスセンサ20における使用時間に係る期間である。
As a preferred mode of correction by the instruction value correction means, the correction rate after the use initial period has elapsed is made smaller than the correction rate for the use initial period.
Here, the “initial period of use” refers to a period in which the characteristic change over time is extremely large from the deterioration characteristics of the electrochemical gas sensor itself such as the constant potential electrolytic gas sensor 20, and specifically, for example, for two months. is there.
In addition, this initial use period is a period related to the use time in the constant potential electrolytic gas sensor 20.

使用初期期間経過後の補正率を使用初期期間の補正率より小さくすることにより、定電位電解式ガスセンサ20の劣化特性に由来する劣化状態に応じて使用初期期間においては大きな補正が行われ、また、当該使用初期期間経過後においては前記補正に比して小さな補正が行われることから、一層信頼の高いガス検知を確実に行うことができる。   By making the correction rate after the initial period of use less than the correction rate of the initial use period, a large correction is performed in the initial use period according to the deterioration state derived from the deterioration characteristics of the constant potential electrolytic gas sensor 20, and After the initial period of use, a correction that is smaller than the correction is performed, so that more reliable gas detection can be reliably performed.

指示値補正手段による検知対象ガス濃度の指示値の補正率の程度は、例えば実際に電気化学式ガス検知器10が用いられる環境下において、ガス検知器本体11自体の有する劣化特性を測定し、この測定結果に基づいて適宜に定めることができる。   The degree of correction of the indicated value of the gas concentration to be detected by the indicated value correcting means is determined by measuring the deterioration characteristics of the gas detector main body 11 itself in an environment where the electrochemical gas detector 10 is actually used. It can be determined as appropriate based on the measurement result.

指示値補正手段による補正の具体的な一例としては、2カ月間の使用初期期間中においては、月間の補正率を初期値の5〜10%とし、当該使用初期期間経過後においては、月間の補正率を初期値の1〜3%とする。   As a specific example of the correction by the instruction value correction means, during the initial use period of 2 months, the monthly correction rate is set to 5 to 10% of the initial value. The correction rate is 1 to 3% of the initial value.

このような構成を有する電気化学式ガス検知器10は、ガス検知器本体11において、定電位電解式ガスセンサ20における電解液用セル21の電解液収容空間21A内に、少なくとも作用極34、対極35および参照極36が浸された状態となる適宜の量の電解液が収容されることによってガス検知動作が可能となるものであり、そのガス検知動作中においてはポテンショスタット回路39により作用極34と、参照極36との間の電位が一定に保たれており、ガス導入口13Aを介してガス用セル13に被検査ガスが導入されると、この被検査ガス中に存在する検知対象ガスが定電位電解式ガスセンサ20の第1のガス透過膜31を透過することによって作用極34において電気分解され、この作用極34と、対極35とにおいて、各々、電気化学反応が起こることに起因して当該作用極34および対極35との間に流れる電解電流値によって示される出力値を制御部において測定し、この出力値の大きさと、検知対象ガス濃度とが比例関係にあることを利用し、制御部において定電位電解式ガスセンサ20の出力値に対する検知対象ガス濃度の指示値に基づいて検知対象ガス濃度が特定され、その結果、被検査ガス中における検知対象ガス濃度を検知することができる。   The electrochemical gas detector 10 having such a configuration includes at least a working electrode 34, a counter electrode 35, and a counter electrode 35 in the electrolyte solution containing space 21 </ b> A of the electrolyte cell 21 in the constant potential electrolytic gas sensor 20 in the gas detector body 11. A gas detection operation can be performed by accommodating an appropriate amount of electrolyte in which the reference electrode 36 is immersed, and during the gas detection operation, the potentiostat circuit 39 and the working electrode 34, When the potential between the reference electrode 36 is kept constant and the gas to be inspected is introduced into the gas cell 13 through the gas inlet 13A, the detection target gas existing in the gas to be inspected is fixed. By passing through the first gas permeable membrane 31 of the electrolysis gas sensor 20, it is electrolyzed at the working electrode 34, and the working electrode 34 and the counter electrode 35 are respectively An output value indicated by the value of the electrolytic current flowing between the working electrode 34 and the counter electrode 35 due to the occurrence of the electrochemical reaction is measured in the control unit, and the magnitude of the output value and the concentration of the detection target gas are determined. Using the proportional relationship, the control unit specifies the detection target gas concentration based on the indication value of the detection target gas concentration with respect to the output value of the constant potential electrolytic gas sensor 20, and as a result, the detection target in the gas to be inspected. Gas concentration can be detected.

以上の電気化学式ガス検知器10においては、使用時間が大きくなるに従って、例えば第1のガス透過膜31および第2のガス透過膜32の汚れ、作用極34、対極35および参照極36の各々を構成する金属の酸化、電解液の触媒作用の劣化などに起因して定電位電解式ガスセンサ20の出力値にバラツキが生じてガス検出性能が低下し、その結果、予め初期値として制御部に記録されている検知対象ガス濃度の指示値に従って特定される検知対象ガス濃度が実際上の検知対象ガス濃度よりも小さくなってしまうこととなるが、指示値補正手段により、定電位電解式ガスセンサ20において経時的に生じるガス検出性能の低下を、その程度に応じて当該定電位電解式ガスセンサ20の出力値に対する検知対象ガス濃度の指示値が大きくなるよう補正して補償することができるため、定電位電解式ガスセンサ20に経時的な特性変化が生じても、検知対象ガス濃度の指示値において、ガス濃度検知性能が低下することが抑制される。
従って、電気化学式ガス検知器10によれば、信頼性の高いガス検知を長期間にわたって行うことができる。
実際上、このような電気化学式ガス検知器10は、例えば自動車道のトンネル内などの自動車の排気ガス等が滞留する劣悪な環境下において検知対象ガス濃度の検知を行うものとして好適に用いることができる。
In the electrochemical gas detector 10 described above, as the usage time increases, for example, contamination of the first gas permeable membrane 31 and the second gas permeable membrane 32, the working electrode 34, the counter electrode 35, and the reference electrode 36 are removed. The output value of the constant potential electrolysis gas sensor 20 varies due to oxidation of the constituent metals, deterioration of the catalytic action of the electrolyte, and the like, and the gas detection performance deteriorates. As a result, the initial value is recorded in the control unit in advance. The detection target gas concentration specified in accordance with the indicated value of the detection target gas concentration will be smaller than the actual detection target gas concentration. The indicated value of the gas concentration to be detected with respect to the output value of the constant potential electrolysis gas sensor 20 increases according to the degree of deterioration in gas detection performance that occurs over time. It is possible to cormorants corrected and compensated, even temporal characteristic change in potential electrolysis type gas sensor 20 occurs, the indicated value of the detection target gas concentration, gas concentration detection performance is suppressed to decrease.
Therefore, the electrochemical gas detector 10 can perform highly reliable gas detection over a long period of time.
In practice, such an electrochemical gas detector 10 is preferably used as one that detects the concentration of a gas to be detected in a poor environment in which, for example, an automobile exhaust gas or the like stays in a tunnel on a motorway. it can.

また、この電気化学式ガス検知器10によれば、長期間にわたって信頼性の高いガス検知を行うことができることから、一のメンテナンス後に次のメンテナンスを行うまでの間のメンテナンス期間が大きくなるため、特に、ガス検知器のメンテナンスのために、例えば自動車の通行を一時的に停止する必要のある自動車道のトンネル内などにおいて用いる場合には、メンテナンス回数を少なくすることができる、という利点もある。   In addition, according to the electrochemical gas detector 10, since a highly reliable gas detection can be performed over a long period of time, a maintenance period between one maintenance and the next maintenance is increased. For maintenance of the gas detector, for example, when it is used in a tunnel of an automobile road where it is necessary to temporarily stop the traffic of the automobile, there is an advantage that the number of maintenance can be reduced.

更に、電気化学式ガス検知器10は、例えばその内部における検知対象ガス濃度を一定レベル以下に維持するための排気機構を備えたトンネル内において、当該排気機構の作動を制御する制御装置における検知対象ガス濃度を検知するガス検知部として用いることができ、この場合には、当該ガス検知部において検知された検知対象ガス濃度が、トンネル内の排気機構の制御に用いられることとなるため、ガス検知部におけるガス検知が信頼性の高いものとなり、その結果、制御装置によって排気機構の作動を確実に制御することができる。   Furthermore, the electrochemical gas detector 10 is, for example, a detection target gas in a control device that controls the operation of the exhaust mechanism in a tunnel having an exhaust mechanism for maintaining the concentration of the detection target gas in the interior below a certain level. It can be used as a gas detection unit that detects the concentration. In this case, the gas detection unit detects the concentration of the detection target gas detected in the gas detection unit, so that the gas detection unit As a result, the operation of the exhaust mechanism can be reliably controlled by the control device.

この電気化学式ガス検知器10は、一酸化炭素ガスを検知対象ガスとして好適に用いることができる。   The electrochemical gas detector 10 can suitably use carbon monoxide gas as a detection target gas.

以上において、電気化学式ガスセンサとして定電位電解式ガスセンサを備えた電気化学式ガス検知器について説明したが、本発明はこれに限定されるものではなく、電気化学式センサからの出力値に対する検知対象ガス濃度の指示値を経時的に増加する補正を行う指示値補正手段を備えるものであれば、その他の構成部材としては種々のものを用いることができる。
例えば、電気化学式ガスセンサとしては、ガルバニ電池式ガスセンサを用いることができる。
In the above, the electrochemical gas detector provided with the constant potential electrolytic gas sensor as the electrochemical gas sensor has been described, but the present invention is not limited to this, and the concentration of the detection target gas concentration with respect to the output value from the electrochemical sensor is not limited to this. Various other members can be used as long as they include instruction value correction means for correcting the instruction value to increase over time.
For example, a galvanic cell type gas sensor can be used as the electrochemical gas sensor.

以下、本発明の作用効果を確認するために行った実験について説明する。   Hereinafter, experiments conducted for confirming the effects of the present invention will be described.

〔実験例1〕
図1の構成に従い、電気化学式ガスセンサとして定電位電解式ガスセンサを備え、一酸化炭素ガスを検知対象ガスとする電気化学式ガス検知器(以下、「電気化学式ガス検知器(1)」ともいう。)を作製した。
この電気化学式ガス検知器(1)においては、指示値補正手段として、2カ月間の初期期間中においては、月間の補正率を初期値の6%とし、当該初期期間経過後においては、月間の補正率を初期値の2%とする補正を行う、マイクロコンピューターを用いた。
[Experimental Example 1]
In accordance with the configuration of FIG. 1, an electrochemical gas sensor including a constant potential electrolytic gas sensor as an electrochemical gas sensor and using carbon monoxide gas as a detection target gas (hereinafter also referred to as “electrochemical gas detector (1)”). Was made.
In this electrochemical gas detector (1), as the indicated value correction means, during the initial period of 2 months, the monthly correction rate is set to 6% of the initial value. A microcomputer that performs correction with a correction rate of 2% of the initial value was used.

作製した電気化学式ガス検知器(1)を、濃度100ppmの一酸化炭素ガス雰囲気中に6カ月間配置し、1カ月毎にガス検知結果を確認するガス検知テストを行ったところ、6カ月間の間、実用上問題のないガス濃度検知性能が維持されることが確認された。   The produced electrochemical gas detector (1) was placed in a carbon monoxide gas atmosphere at a concentration of 100 ppm for 6 months, and a gas detection test was performed to confirm the gas detection results every month. In the meantime, it was confirmed that the gas concentration detection performance without any practical problem was maintained.

〔比較実験例1〕
電気化学式ガス検知器(1)において、指示値補正手段を備えていないこと以外は電気化学式ガス検知器(1)と同様の構成を有する電気化学式ガス検知器(以下、「比較用電気化学式ガス検知器(1)」ともいう。)を作製した。
[Comparative Experiment Example 1]
The electrochemical gas detector (1) has the same configuration as the electrochemical gas detector (1) except that it does not include the indicated value correction means (hereinafter referred to as “comparison electrochemical gas detector”). (Also referred to as “vessel (1)”).

作製した比較用電気化学式ガス検知器(1)に対して実験例(1)と同様の手法によってガス検知テストを行ったところ、使用時間が大きくなるに従ってガス濃度検知性能が低下することが確認された。   When a gas detection test was performed on the produced comparative electrochemical gas detector (1) by the same method as in Experimental Example (1), it was confirmed that the gas concentration detection performance deteriorated as the usage time increased. It was.

以上の実験例(1)および比較実験例(1)により、本発明に係る電気化学式ガス検知器(1)によれば、電気化学式ガスセンサに経時的な特性変化が生じても、ガス濃度検知性能が低下することを抑制することができることが確認された。   According to the experimental example (1) and the comparative experimental example (1), the electrochemical gas detector (1) according to the present invention can detect the gas concentration even if the electrochemical gas sensor changes in characteristics over time. It was confirmed that it can suppress that falls.

〔実験例2〕
実験例(1)における電気化学式ガス検知器(1)を、自動車道のトンネル内に210日間配置し、定期的に、一酸化炭素ガス濃度100ppmのガスを被検査対象ガスとしてガス用セルに導入することによって検知される一酸化炭素ガス濃度を確認するガス検知テストを行った。結果を図2において曲線aにより示す。
[Experiment 2]
The electrochemical gas detector (1) in the experimental example (1) is placed in a tunnel on the motorway for 210 days, and a gas with a carbon monoxide concentration of 100 ppm is periodically introduced into the gas cell as a gas to be inspected. A gas detection test was conducted to confirm the concentration of carbon monoxide gas detected by the test. The result is shown by curve a in FIG.

〔比較実験例2〕
実験例(2)において、電気化学式ガス検知器(1)に代えて、比較実験例(1)における比較用電気化学式ガス検知器(1)を用いたこと以外は実験例(2)と同様の手法によってガス検知テストを行った。結果を図2において曲線bにより示す。
[Comparative Experiment 2]
In Experimental Example (2), the same as in Experimental Example (2) except that the electrochemical gas detector for comparison (1) in Comparative Experimental Example (1) was used instead of the electrochemical gas detector (1). The gas detection test was conducted by the method. The result is shown by curve b in FIG.

以上の実験例(2)および比較実験例(2)により、本発明に係る電気化学式ガス検知器(1)によれば、自動車道のトンネル内などの自動車の排気ガス等が滞留する劣悪な環境下においても、ガス濃度検知性能が低下することを抑制することができることが確認された。   From the above experimental example (2) and comparative experimental example (2), according to the electrochemical gas detector (1) according to the present invention, an inferior environment in which the exhaust gas of a car such as in a tunnel of a motorway stays. It has been confirmed that the gas concentration detection performance can be prevented from being lowered even at the bottom.

以上の結果から、本発明に係る電気化学式ガス検知器(1)によれば、信頼性の高いガス検知を長期間にわたって行うことができることが確認された。   From the above results, it was confirmed that the electrochemical gas detector (1) according to the present invention can perform highly reliable gas detection over a long period of time.

本発明の電気化学式ガス検知器の構成の一例を示す説明図である。It is explanatory drawing which shows an example of a structure of the electrochemical gas detector of this invention. 実験例(2)および比較用実験例(2)に係る経過日数と検知される一酸化炭素ガス濃度の関係を示す説明図である。It is explanatory drawing which shows the relationship between the elapsed days and the detected carbon monoxide gas density | concentration which concern on Experimental example (2) and Comparative experimental example (2).

符号の説明Explanation of symbols

10 電気化学式ガス検知器
11 ガス検知器本体
13 ガス用セル
13A ガス導入口
13B ガス排出口
20 定電位電解式ガスセンサ
21 電解液用セル
21A 電解液収容用空間
21B 開口
22 連結用部材
23 第1の開口
24 第2の開口
31 第1のガス透過膜
32 第2のガス透過膜
34 作用極
35 対極
36 参照極
39 ポテンショスタット回路
DESCRIPTION OF SYMBOLS 10 Electrochemical gas detector 11 Gas detector main body 13 Gas cell 13A Gas inlet 13B Gas outlet 20 Constant potential electrolytic gas sensor 21 Electrolyte cell 21A Electrolyte storage space 21B Opening 22 Connecting member 23 First Opening 24 Second opening 31 First gas permeable membrane 32 Second gas permeable membrane 34 Working electrode 35 Counter electrode 36 Reference electrode 39 Potentiostat circuit

Claims (5)

電気化学式センサを備え、当該電気化学式センサからの出力値に基づいて検知対象ガス濃度を検知する電気化学式ガス検知器において、
電気化学式センサからの出力値に対する検知対象ガス濃度の指示値を経時的に増加する補正を行う指示値補正手段を備えていることを特徴とする電気化学式ガス検知器。
In an electrochemical gas detector that includes an electrochemical sensor and detects a gas concentration to be detected based on an output value from the electrochemical sensor,
An electrochemical gas detector, comprising: an instruction value correction means for performing correction to increase the instruction value of the detection target gas concentration with respect to the output value from the electrochemical sensor over time.
検知対象ガスが一酸化炭素ガスであることを特徴とする請求項1に記載の電気化学式ガス検知器。   The electrochemical gas detector according to claim 1, wherein the detection target gas is carbon monoxide gas. 指示値補正手段が、使用初期期間経過後は、使用初期期間の補正率より小さい補正率で補正を行うものであることを特徴とする請求項1または請求項2に記載の電気化学式ガス検知器。   3. The electrochemical gas detector according to claim 1, wherein the indicated value correcting means corrects at a correction rate smaller than the correction rate of the initial use period after the initial use period has elapsed. . 自動車道のトンネル内における検知対象ガス濃度の検知に用いられることを特徴とする請求項1〜請求項3のいずれかに記載の電気化学式ガス検知器。   The electrochemical gas detector according to any one of claims 1 to 3, wherein the electrochemical gas detector is used for detecting a concentration of a gas to be detected in a tunnel of an automobile road. 検知された検知対象ガス濃度が、トンネル内の排気機構の制御に用いられることを特徴とする請求項4に記載の電気化学式ガス検知器。   5. The electrochemical gas detector according to claim 4, wherein the detected gas concentration to be detected is used for controlling an exhaust mechanism in the tunnel.
JP2003298771A 2003-08-22 2003-08-22 Electrochemical gas detector Expired - Lifetime JP4458795B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2003298771A JP4458795B2 (en) 2003-08-22 2003-08-22 Electrochemical gas detector

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2003298771A JP4458795B2 (en) 2003-08-22 2003-08-22 Electrochemical gas detector

Publications (2)

Publication Number Publication Date
JP2005069820A true JP2005069820A (en) 2005-03-17
JP4458795B2 JP4458795B2 (en) 2010-04-28

Family

ID=34404177

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2003298771A Expired - Lifetime JP4458795B2 (en) 2003-08-22 2003-08-22 Electrochemical gas detector

Country Status (1)

Country Link
JP (1) JP4458795B2 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006348906A (en) * 2005-06-20 2006-12-28 Tsukuba Technology Seed Kk Liquid feeder
JP2011174722A (en) * 2010-02-23 2011-09-08 Riken Keiki Co Ltd Gas detector
JP2017037549A (en) * 2015-08-12 2017-02-16 新コスモス電機株式会社 Alarm unit
CN110700874A (en) * 2019-09-26 2020-01-17 武汉理工大学 Mine self-propelled air purification equipment
JP2020106482A (en) * 2018-12-28 2020-07-09 東亜ディーケーケー株式会社 Diaphragm type gas sensor and sensor unit
JP2020173143A (en) * 2019-04-09 2020-10-22 株式会社チノー Constant potential electrolytic gas sensor

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7165593B2 (en) * 2019-01-28 2022-11-04 リンナイ株式会社 Combustion device

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02274999A (en) * 1989-04-17 1990-11-09 Shimizu Corp Tunnel exhaust gas disposing method
JPH0443951A (en) * 1990-06-11 1992-02-13 Matsushita Electric Works Ltd Electrochemical system gas sensor
JPH06229980A (en) * 1993-02-04 1994-08-19 Gastec:Kk Constant potential electrolyte type gas sensor
JPH0755764A (en) * 1993-08-12 1995-03-03 Riken Keiki Co Ltd Constant potential electrolysis type acidic gas sensor
JPH10311815A (en) * 1997-05-09 1998-11-24 Japan Storage Battery Co Ltd Method for judging deterioration of electrochemical carbon monoxide gas sensor and calibrating method
JPH1123512A (en) * 1997-07-02 1999-01-29 Riken Keiki Co Ltd Measuring device
JP2000008798A (en) * 1998-06-26 2000-01-11 Hitachi Ltd Tunnel ventilation control device
JP2002071621A (en) * 2000-08-25 2002-03-12 New Cosmos Electric Corp Constant potential electrolytic gas sensor

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02274999A (en) * 1989-04-17 1990-11-09 Shimizu Corp Tunnel exhaust gas disposing method
JPH0443951A (en) * 1990-06-11 1992-02-13 Matsushita Electric Works Ltd Electrochemical system gas sensor
JPH06229980A (en) * 1993-02-04 1994-08-19 Gastec:Kk Constant potential electrolyte type gas sensor
JPH0755764A (en) * 1993-08-12 1995-03-03 Riken Keiki Co Ltd Constant potential electrolysis type acidic gas sensor
JPH10311815A (en) * 1997-05-09 1998-11-24 Japan Storage Battery Co Ltd Method for judging deterioration of electrochemical carbon monoxide gas sensor and calibrating method
JPH1123512A (en) * 1997-07-02 1999-01-29 Riken Keiki Co Ltd Measuring device
JP2000008798A (en) * 1998-06-26 2000-01-11 Hitachi Ltd Tunnel ventilation control device
JP2002071621A (en) * 2000-08-25 2002-03-12 New Cosmos Electric Corp Constant potential electrolytic gas sensor

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006348906A (en) * 2005-06-20 2006-12-28 Tsukuba Technology Seed Kk Liquid feeder
JP2011174722A (en) * 2010-02-23 2011-09-08 Riken Keiki Co Ltd Gas detector
JP2017037549A (en) * 2015-08-12 2017-02-16 新コスモス電機株式会社 Alarm unit
JP2020106482A (en) * 2018-12-28 2020-07-09 東亜ディーケーケー株式会社 Diaphragm type gas sensor and sensor unit
JP7266170B2 (en) 2018-12-28 2023-04-28 東亜ディーケーケー株式会社 Diaphragm type gas sensor and sensor unit
JP2020173143A (en) * 2019-04-09 2020-10-22 株式会社チノー Constant potential electrolytic gas sensor
JP7260376B2 (en) 2019-04-09 2023-04-18 株式会社チノー Constant potential electrolytic gas sensor
CN110700874A (en) * 2019-09-26 2020-01-17 武汉理工大学 Mine self-propelled air purification equipment

Also Published As

Publication number Publication date
JP4458795B2 (en) 2010-04-28

Similar Documents

Publication Publication Date Title
JP2016524789A (en) Estimating the charge state of the positive electrolyte solution in a working redox flow battery cell without a reference electrode
EP1593962B1 (en) Eletrochemical oxygen sensor
EP2366995A1 (en) Amperometric sensor
JP4458795B2 (en) Electrochemical gas detector
GB2582049A (en) Method for operating an electrolysis system and electrolysis system
US10031105B2 (en) Electrochemical total organic carbon analyzer
CN1841059A (en) Method of checking the function of a sensor
EP0432840A2 (en) Solid-state sensor for the determination of the concentration of gases which can react with hydrogen
JP2006194708A (en) Electrochemical oxygen sensor
KR20160077125A (en) Potentiostatic electrolytic gas sensor
US6404205B1 (en) Method for testing the reliability of an electrochemical gas sensor
EP1672362B1 (en) Coulometric water vapor sensor
EP2251683B1 (en) Method of regenerating electrochemical gas sensors
JP3881540B2 (en) Constant potential electrolysis gas sensor and gas detector
JPH10311815A (en) Method for judging deterioration of electrochemical carbon monoxide gas sensor and calibrating method
JP2009047431A (en) Gas concentration detector and gas concentration detecting method
JP5320324B2 (en) Gas detector
KR101115050B1 (en) Method for measuring dissolved hydrogen in boiler water
WO2017022812A1 (en) Constant potential electrolytic gas sensor
JP6466022B1 (en) Constant potential electrolytic gas sensor
JP2005127927A (en) Continuous exhaust gas analyzer equipped with controlled potential electrolysis type gas sensor
JP7260376B2 (en) Constant potential electrolytic gas sensor
JP6315983B2 (en) Constant potential electrolytic gas sensor
JP2020085877A (en) Constant potential electrolysis gas sensor
JPH0334690Y2 (en)

Legal Events

Date Code Title Description
A711 Notification of change in applicant

Free format text: JAPANESE INTERMEDIATE CODE: A711

Effective date: 20050530

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A821

Effective date: 20050602

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20050804

A711 Notification of change in applicant

Free format text: JAPANESE INTERMEDIATE CODE: A712

Effective date: 20051215

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A821

Effective date: 20051215

A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20060802

RD02 Notification of acceptance of power of attorney

Free format text: JAPANESE INTERMEDIATE CODE: A7422

Effective date: 20060802

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A821

Effective date: 20060802

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20090313

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20090421

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20090619

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20091006

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20091202

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20100202

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20100209

R150 Certificate of patent or registration of utility model

Ref document number: 4458795

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20130219

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20130219

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20160219

Year of fee payment: 6

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

EXPY Cancellation because of completion of term