JPS6225988B2 - - Google Patents
Info
- Publication number
- JPS6225988B2 JPS6225988B2 JP56142145A JP14214581A JPS6225988B2 JP S6225988 B2 JPS6225988 B2 JP S6225988B2 JP 56142145 A JP56142145 A JP 56142145A JP 14214581 A JP14214581 A JP 14214581A JP S6225988 B2 JPS6225988 B2 JP S6225988B2
- Authority
- JP
- Japan
- Prior art keywords
- heater
- gas
- sensor
- voltage
- gas concentration
- 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.)
- Expired
Links
- 239000007789 gas Substances 0.000 claims description 37
- 238000001514 detection method Methods 0.000 claims description 11
- 239000001257 hydrogen Substances 0.000 claims description 8
- 229910052739 hydrogen Inorganic materials 0.000 claims description 8
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 8
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 7
- 230000035945 sensitivity Effects 0.000 claims description 6
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 5
- 239000004065 semiconductor Substances 0.000 claims description 5
- 229910044991 metal oxide Inorganic materials 0.000 claims description 4
- 150000004706 metal oxides Chemical class 0.000 claims description 4
- 150000002431 hydrogen Chemical class 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 9
- 230000007774 longterm Effects 0.000 description 5
- 235000019441 ethanol Nutrition 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 2
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 2
- 229910001887 tin oxide Inorganic materials 0.000 description 2
- 229910006404 SnO 2 Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000010411 cooking Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000002123 temporal effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/0004—Gaseous mixtures, e.g. polluted air
- G01N33/0009—General constructional details of gas analysers, e.g. portable test equipment
- G01N33/0062—General constructional details of gas analysers, e.g. portable test equipment concerning the measuring method or the display, e.g. intermittent measurement or digital display
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Analytical Chemistry (AREA)
- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Physics & Mathematics (AREA)
- Combustion & Propulsion (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Description
【発明の詳細な説明】
本発明は、金属酸化物半導体を使用した可燃性
ガス検知装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combustible gas detection device using a metal oxide semiconductor.
従来の酸化錫（SnO2）を主成分とする半導体を
使用した可燃性ガス検知装置においては、第１図
に示すような回路で検知される。図中、Ｓが酸化
錫を主成分としたガス感応体、ＲHはその感応体
Ｓを加熱するためのヒーター、ＲLはガス検知素
子の出力ＶOを取り出すための抵抗である。この
従来例の欠点は長期間使用しているうちに、水
素、エチルアルコール（以下アルコールという）
ガスでの感度が上昇し、警報器が高感度になり過
ぎて調理の際に発生する雑ガスで誤報を発生しや
すくなることである。長期間の使用で警報を発す
る最低のガス濃度がどのように変るかを示したの
が第２図である。 In a conventional combustible gas detection device using a semiconductor mainly composed of tin oxide (SnO 2 ), detection is performed using a circuit as shown in FIG. In the figure, S is a gas sensitive body mainly composed of tin oxide, R H is a heater for heating the sensitive body S, and R L is a resistor for taking out the output V O of the gas detection element. The disadvantage of this conventional method is that after long-term use, hydrogen, ethyl alcohol (hereinafter referred to as alcohol)
The sensitivity to gas increases, making the alarm too sensitive and making false alarms more likely to occur due to miscellaneous gases generated during cooking. Figure 2 shows how the minimum gas concentration that triggers an alarm changes over a long period of use.
本発明は、かかる欠点に鑑みなされたもので、
その目的とするところは、金属酸化物半導体を使
用した可燃性ガス検知装置において、水素、アル
コールでの長期的な経時変化による感度上昇を抑
えるにある。 The present invention was made in view of these drawbacks,
The purpose of this is to suppress the increase in sensitivity due to long-term changes in hydrogen and alcohol in combustible gas detection devices using metal oxide semiconductors.
可燃性ガス検知素子においては、その特性はセ
ンサーの温度に影響される。第３図、第４図はセ
ンサーＳを加熱するヒーターＲHにかける電圧を
変えた時、センサー出力ＶOがガス種、ガス濃度
によつてどう変るかを示したもので、第３図はヒ
ーター電圧を低くしてセンサー温度を比較的低く
した場合であり、第４図はヒーター電圧を高くし
てセンサー温度を高くした場合である。図からわ
かるように、メタンでの温度（ヒーター電圧）の
影響が著しい。従つて、水素、メタン両ガス共に
検知しようとする場合、センサー温度はある程度
高くなければならない。 In a combustible gas sensing element, its characteristics are influenced by the temperature of the sensor. Figures 3 and 4 show how the sensor output V O changes depending on the gas type and gas concentration when the voltage applied to the heater R H that heats the sensor S is changed. This is a case where the heater voltage is lowered and the sensor temperature is made relatively low, and FIG. 4 is a case where the heater voltage is increased and the sensor temperature is made higher. As can be seen from the figure, the effect of temperature (heater voltage) on methane is significant. Therefore, when attempting to detect both hydrogen and methane gases, the sensor temperature must be relatively high.
一方、長期的な経時変化に対してのヒーター電
圧（つまりセンサー温度）の影響がどうなるかを
示したのが第５図である。この例はガス種が水素
の場合であり、図のＶH＝Highに相当するのが第
２図における水素の経時変動である。これからヒ
ーター電圧としては低い方が長期的には安定する
傾向がある。尚、第５図は一定のガス濃度の時の
センサー出力ＶOとしてとらえたものであり、Ｖ
H＝Lowの時も測定時だけはＶH＝Highの条件で
測つたものである。 On the other hand, FIG. 5 shows how the heater voltage (that is, sensor temperature) affects long-term changes over time. This example is for the case where the gas type is hydrogen, and the temporal variation of hydrogen in FIG. 2 corresponds to V H =High in the diagram. From now on, there is a tendency that the lower the heater voltage, the more stable it will be in the long term. In addition, Fig. 5 is taken as the sensor output V O at a constant gas concentration, and V
Even when H = Low, only the measurement was performed under the condition of V H = High.
つまり本発明では、常時は比較的低いヒーター
電圧にしてセンサー温度を下げておき、ある程度
ガス濃度が上つて来た時点でヒーター電圧を上げ
（センサー温度が上る）、その後警報を発すべきか
どうかの判断をさせようとするものである。その
ガス濃度とセンサー出力、ヒーター電圧の関係を
示したのが第６図である。 In other words, in the present invention, the sensor temperature is lowered by keeping the heater voltage relatively low at all times, and when the gas concentration rises to a certain extent, the heater voltage is raised (sensor temperature rises), and then it is determined whether or not to issue an alarm. It's trying to get you to make a decision. FIG. 6 shows the relationship between the gas concentration, sensor output, and heater voltage.
第７図は本発明の一実施例を示す回路図で、常
時はセンサーＳの出力、つまり抵抗ＲLの端子間
電圧ＶOが低く電圧比較器Ｃからの出力は出てい
ない。従つてトランジスタＱは不導通の状態とな
つている。このためセンサーＳを加熱するヒータ
ーＲHには電圧ＶのヒーターＲHと抵抗R1で分割
された値が印加されており、抵抗R1が直列に入
つている分、ヒーター電圧は低く、センサー温度
は下つている。この状態でガスの濃度が上つて来
るとセンサー出力が少しづつ上つて来る。そし
て、その値が電圧比較器Ｃのしきい値を越える
と、電圧比較器Ｃの出力が出てトランジスタＱが
導通する。これによつてほとんど電圧Ｖすべてが
ヒーターＲHにかかることになり、センサー温度
が上つて行く。そこで、センサー出力は大きく上
昇する（メタンの場合）。更にガス濃度が上つて
行き警報レベルに達することにより、警報器は発
報することになる。実際の使用ではガス濃度が上
ることはまれでありそれによつてヒーター電圧が
上ることによる長期的な経時変化への影響はない
と見てよい。 FIG. 7 is a circuit diagram showing an embodiment of the present invention. Normally, the output of the sensor S, that is, the voltage V O between the terminals of the resistor R L is low, and no output is output from the voltage comparator C. Therefore, transistor Q is in a non-conducting state. Therefore, a voltage divided by the voltage V of the heater R H and the resistor R 1 is applied to the heater R H that heats the sensor S, and since the resistor R 1 is connected in series, the heater voltage is low and the sensor The temperature is dropping. In this state, as the gas concentration increases, the sensor output increases little by little. When the value exceeds the threshold value of voltage comparator C, the output of voltage comparator C is output and transistor Q becomes conductive. This causes almost all of the voltage V to be applied to the heater R H , causing the sensor temperature to rise. Therefore, the sensor output increases significantly (in the case of methane). As the gas concentration further increases and reaches the alarm level, the alarm will sound. In actual use, the gas concentration rarely increases, and therefore, it can be seen that the increase in heater voltage has no effect on long-term changes over time.
本発明は上記のように、金属酸化物半導体を主
成分とする可燃性ガス検知素子を用いた可燃性ガ
ス検知装置において、常時はヒーターでの消費電
力を低くしてセンサー温度を低くし、ある程度ガ
ス濃度が上つた後でヒーター消費電力を上げセン
サー温度を上げるようにしたことを特徴とするの
で、ガスの濃度がある程度以上にならないとヒー
ター電圧が上らず、長期での水素、アルコールガ
スでの感度上昇を大巾に減らすことができる。従
つてこれまで問題とされた使つているうちに感度
が良くなり過ぎてたびたび誤報を発するという問
題が大巾に軽減された。尚、１個のガス検知素子
に複数のヒーターを有するものにあつては１個の
ヒーターを常時一定電圧で加熱しガス濃度が上つ
た時別のヒーターでの加熱を追加しても同等の効
果を奏する。 As described above, the present invention provides a combustible gas detection device using a combustible gas detection element containing a metal oxide semiconductor as a main component, by constantly lowering the power consumption of the heater and lowering the sensor temperature to a certain extent. The feature is that the heater power consumption is increased to raise the sensor temperature after the gas concentration rises, so the heater voltage will not rise unless the gas concentration exceeds a certain level, so it will not work with hydrogen or alcohol gas over a long period of time. The increase in sensitivity can be greatly reduced. Therefore, the problem that had been encountered up until now, where the sensitivity became too good during use and caused frequent false alarms, has been greatly alleviated. If one gas detection element has multiple heaters, the same effect can be obtained by heating one heater at a constant voltage and then adding another heater when the gas concentration rises. play.
第１図は従来例を示す回路図、第２図は経過年
数に対する警報を発する最低ガス濃度の特性図、
第３図及び第４図はガス濃度に対するセンサー出
力の特性図、第５図は経過年数に対するセンサー
出力の特性図、第６図はガス濃度に対するセンサ
ー出力及びヒーター電圧の関係図、第７図は本発
明の一実施例を示す回路図である。
Figure 1 is a circuit diagram showing a conventional example, Figure 2 is a characteristic diagram of the minimum gas concentration that issues an alarm depending on the number of years that have passed.
Figures 3 and 4 are characteristic diagrams of sensor output with respect to gas concentration, Figure 5 is a characteristic diagram of sensor output with respect to elapsed years, Figure 6 is a relationship diagram of sensor output and heater voltage with respect to gas concentration, and Figure 7 is a characteristic diagram of sensor output with respect to gas concentration. FIG. 1 is a circuit diagram showing an embodiment of the present invention.
Claims (1)
検知素子を用いた可燃性ガス検知装置において、
常時はヒーターでの消費電力を低くして、水素、
アルコールガス等の感度の経時変化が少ない低温
のセンサー温度に保持し、ある一定以上のガス濃
度検出後、ヒーター消費電力を高くして、メタン
ガスが水素やアルコールガスと略同感度で検出で
きるセンサー温度に昇温することを特徴とする可
燃性ガス検知装置。1. In a combustible gas detection device using a combustible gas detection element containing a metal oxide semiconductor as a main component,
At all times, the power consumption of the heater is kept low, and hydrogen,
The sensor temperature is maintained at a low temperature where the sensitivity of alcohol gas, etc. does not change over time, and after detecting a gas concentration above a certain level, the heater power consumption is increased, so that methane gas can be detected with approximately the same sensitivity as hydrogen or alcohol gas. A combustible gas detection device characterized by a temperature rise of .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14214581A JPS5842962A (en) | 1981-09-08 | 1981-09-08 | Detection apparatus of combustible gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14214581A JPS5842962A (en) | 1981-09-08 | 1981-09-08 | Detection apparatus of combustible gas |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5842962A JPS5842962A (en) | 1983-03-12 |
| JPS6225988B2 true JPS6225988B2 (en) | 1987-06-05 |
Family
ID=15308403
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14214581A Granted JPS5842962A (en) | 1981-09-08 | 1981-09-08 | Detection apparatus of combustible gas |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5842962A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01111284U (en) * | 1988-01-21 | 1989-07-26 |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5635628A (en) * | 1995-05-19 | 1997-06-03 | Siemens Aktiengesellschaft | Method for detecting methane in a gas mixture |
| JP4734833B2 (en) * | 2004-03-08 | 2011-07-27 | パナソニック株式会社 | Fuel cell system |
| JP4734834B2 (en) * | 2004-03-08 | 2011-07-27 | パナソニック株式会社 | Fuel cell system with combustible gas sensor |
| JP4734856B2 (en) * | 2004-06-23 | 2011-07-27 | パナソニック株式会社 | Fuel cell system |
| JP5517963B2 (en) * | 2011-02-10 | 2014-06-11 | 富士電機株式会社 | Gas detector |
| CN102520121B (en) * | 2011-12-08 | 2015-06-24 | 中国电力科学研究院 | Environment-friendly type real-time detection apparatus for analysis of components in sulfur hexafluoride gas and method used therein |
| JP6576056B2 (en) * | 2015-03-10 | 2019-09-18 | 新コスモス電機株式会社 | Gas detection device and control method thereof |
| DE202019100292U1 (en) | 2018-01-19 | 2019-05-09 | Lg Electronics Inc. | air cleaner |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52121391A (en) * | 1976-04-06 | 1977-10-12 | Tokai Konetsu Kogyo Kk | Gas sensing apparatus with self cleaning mechanisms |
| JPS57178148A (en) * | 1981-04-27 | 1982-11-02 | Matsushita Electric Works Ltd | Detection apparatus of combustible gas |
-
1981
- 1981-09-08 JP JP14214581A patent/JPS5842962A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52121391A (en) * | 1976-04-06 | 1977-10-12 | Tokai Konetsu Kogyo Kk | Gas sensing apparatus with self cleaning mechanisms |
| JPS57178148A (en) * | 1981-04-27 | 1982-11-02 | Matsushita Electric Works Ltd | Detection apparatus of combustible gas |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01111284U (en) * | 1988-01-21 | 1989-07-26 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5842962A (en) | 1983-03-12 |
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