JPH0358459B2 - - Google Patents
Info
- Publication number
- JPH0358459B2 JPH0358459B2 JP59095960A JP9596084A JPH0358459B2 JP H0358459 B2 JPH0358459 B2 JP H0358459B2 JP 59095960 A JP59095960 A JP 59095960A JP 9596084 A JP9596084 A JP 9596084A JP H0358459 B2 JPH0358459 B2 JP H0358459B2
- Authority
- JP
- Japan
- Prior art keywords
- gas
- changes
- pressure
- crystal
- section
- 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 - Lifetime
Links
- 238000001514 detection method Methods 0.000 claims description 17
- 238000005259 measurement Methods 0.000 claims description 4
- 239000007789 gas Substances 0.000 description 41
- 239000013078 crystal Substances 0.000 description 29
- 230000005284 excitation Effects 0.000 description 10
- 238000010586 diagram Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 5
- 239000004065 semiconductor Substances 0.000 description 5
- 230000035945 sensitivity Effects 0.000 description 5
- 230000010355 oscillation Effects 0.000 description 4
- 206010021143 Hypoxia Diseases 0.000 description 2
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001294 propane Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/02—Analysing fluids
- G01N29/036—Analysing fluids by measuring frequency or resonance of acoustic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N5/00—Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid
- G01N5/02—Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid by absorbing or adsorbing components of a material and determining change of weight of the adsorbent, e.g. determining moisture content
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/025—Change of phase or condition
- G01N2291/0256—Adsorption, desorption, surface mass change, e.g. on biosensors
Landscapes
- Physics & Mathematics (AREA)
- Biochemistry (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Acoustics & Sound (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】
〔産業上の利用分野〕
この発明は、圧電振動子を利用して気体の種
類、および組成変化を検出することができるよう
にしたガス検出装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a gas detection device capable of detecting the type of gas and changes in composition using a piezoelectric vibrator.
都市ガス、プロパンガスなどの漏れ、あるいは
酸欠防止などのために気体の組成変化を検出する
ガス検出装置がある。
There are gas detection devices that detect gas composition changes to prevent leaks of city gas, propane gas, etc., or to prevent oxygen deficiency.
従来のかかる検出装置の大部分は半導体の抵抗
変化を利用しているが、半導体式のガス漏れ検出
装置は半導体センサ部への水蒸気や、他の活性気
体の吸着による感度変化によつて誤動作が生じた
り、長期間にわたる使用では吸着気体の効果や半
導体センサ自身の経時変化のために、感度が変化
したりまつたく感度がなくなるなどの欠点があつ
た。 Most conventional detection devices utilize changes in the resistance of semiconductors, but semiconductor-based gas leak detection devices can malfunction due to changes in sensitivity due to adsorption of water vapor or other active gases to the semiconductor sensor section. However, when used for a long period of time, the sensor has disadvantages such as changes in sensitivity or loss of sensitivity due to the effects of adsorbed gas and changes in the semiconductor sensor itself over time.
この発明は、かかる実状にかんがみてなされた
もので、圧電物質が屈曲振動を行うときの電気的
な特性が気体の圧力や種類によつて変化すること
を利用して、小型で、かつ堅牢であり、長期間に
わたつて安定した感度をもつガス検出装置を提供
するものである。
This invention was made in view of the above circumstances, and takes advantage of the fact that the electrical characteristics of piezoelectric materials change depending on the pressure and type of gas when they undergo bending vibration. This provides a gas detection device with stable sensitivity over a long period of time.
屈曲振動を行つている圧電振動子が、気体の圧
力によつてその電気的特性が変化することは、例
えば特公昭48−16584号公報に記載されているよ
うに公知の事実となつている。
It is a well-known fact, for example, as described in Japanese Patent Publication No. 16584/1984, that the electrical characteristics of a piezoelectric vibrator that undergoes flexural vibration change depending on the pressure of the gas.
この特許公報によると、第５図に示すように開
孔２を設けた容器１の中に水晶振動子３、その電
極４，５、リード線８，９をブツシング６，７に
よつて容器１の中に気密性を保つて収納し、図示
しない振動回路（発振回路）によつて前記水晶振
動子３に振動を与えると、水晶振動子３は容器１
内の圧力によつてそのＱを変化するので、Ｑの変
化を発振レベルで測定することによつて容器１内
の圧力を知ることができるという技術が記載され
ている。 According to this patent publication, as shown in FIG. When the crystal resonator 3 is housed in the container 1 while maintaining airtightness and is given vibration by a vibration circuit (oscillation circuit) not shown, the crystal resonator 3 moves into the container 1.
A technique is described in which the pressure inside the container 1 can be determined by measuring the change in Q at the oscillation level since the Q changes depending on the pressure inside the container 1.
この発明は、かかる気体の圧力と圧電振動子の
ふるまいをさらに詳細に観察した結果、振動子の
電気的な特性が気体の密度と粘性、つまりガスの
種類によつても影響されることを発見してなされ
たものである。 As a result of observing the pressure of the gas and the behavior of the piezoelectric vibrator in more detail, this invention discovered that the electrical characteristics of the vibrator are also affected by the density and viscosity of the gas, that is, the type of gas. It was done by
以下、この発明のガス検出装置の実施例につい
て説明する。
Embodiments of the gas detection device of the present invention will be described below.
第１図は、この発明の概要を示すガス検出装置
のブロツク図で、１０ａ，１０ｂは同一の形状に
構成されている水晶振動部である。一方の水晶振
動部１０ａは外圧に順応したその体積が変化する
ベローズ１１ａまたは隔膜に密閉収納されてお
り、他方の水晶振動部１０ｂは、気体が自由に出
入する開孔を設けた容器１１ｂに収納されてい
る。１２ａ，１２ｂは前記水晶振動部１０ａ，１
０ｂに励振パワーを供給している励振部（発振回
路）、１３ａ，１３ｂは励振部１２ａ，１２ｂか
ら供給されているパワーから水晶振動部１０ａ，
１０ｂの電気的な特性を測定している測定部であ
る。電気的な特性としては水晶振動子に流れる電
流、電圧、および交流インピーダンス等が好まし
い。 FIG. 1 is a block diagram of a gas detection device showing an outline of the present invention, in which reference numerals 10a and 10b are crystal vibrating sections having the same shape. One crystal vibrating part 10a is hermetically housed in a bellows 11a or a diaphragm whose volume changes according to external pressure, and the other crystal vibrating part 10b is housed in a container 11b with an opening through which gas can freely enter and exit. has been done. 12a, 12b are the crystal vibrating parts 10a, 1
The excitation section (oscillation circuit), 13a, 13b that supplies excitation power to the crystal vibrating section 10a, 13b receives the power supplied from the excitation section 12a, 12b.
This is a measurement unit that measures the electrical characteristics of the battery 10b. Preferred electrical characteristics include current flowing through the crystal resonator, voltage, AC impedance, and the like.
１４は測定部１３ａ，１３ｂから検出された信
号を比較して水晶振動部１０ａ，１０ｂの共振電
流、電圧、電力またはインピーダンスの変化を算
出し、この算出値から水晶振動部１０ｂの方に浸
入しているガスの種類や組成の変化、および圧力
を特定する検出部、１５は検出部１４の出力に応
じて組成変化、およびガス種類を表示し、かつ警
報を出力する出力部である。 14 compares the signals detected from the measuring parts 13a and 13b, calculates the change in resonance current, voltage, power, or impedance of the crystal vibrating parts 10a and 10b, and uses the calculated value to calculate the change in the resonance current, voltage, power, or impedance of the crystal vibrating part 10b. A detecting section 15 specifies changes in the type and composition of gas, and pressure, and an output section 15 displays composition changes and gas types according to the output of the detecting section 14, and outputs an alarm.
第２図ａ，ｂは前記水晶振動部１０ａ，１０ｂ
の一実施例を示す水晶振動子の正面図、および側
面図を示したもので、XYカツトされた音叉型水
晶振動子２０のそれぞれの振動片には２組の電極
２１，２１、および２２，２２が密着されて取り
付けられている。 Figures 2a and 2b show the crystal vibrating parts 10a and 10b.
This figure shows a front view and a side view of a crystal resonator showing one embodiment, and each vibrating piece of an XY-cut tuning fork crystal resonator 20 has two sets of electrodes 21, 21, and 22. 22 are attached in close contact.
そして、２組の電極２１，２１、および２２，
２２には励振部１３ａ，１３ｂから音叉型水晶振
動子２０の共振周波数と等しい周波数の交流電圧
が印加される。 Then, two sets of electrodes 21, 21, and 22,
An alternating current voltage having a frequency equal to the resonance frequency of the tuning fork type crystal resonator 20 is applied to the tuning fork type crystal resonator 20 from the excitation parts 13a and 13b.
なお、励振部１３ａ，１３ｂは後述するように
水晶振動子２０を共振素子とする発振回路であつ
てもよい。 Note that the excitation units 13a and 13b may be oscillation circuits using the crystal resonator 20 as a resonant element, as described later.
第３図は、第２図に示したような水晶振動子２
０の共振点におけるインピーダンスＺが振動子を
取りまく気体の圧力、および気体の種類によつて
どのように変化するかを示す実験データである。 Figure 3 shows a crystal oscillator 2 as shown in Figure 2.
This is experimental data showing how the impedance Z at the zero resonance point changes depending on the pressure of the gas surrounding the vibrator and the type of gas.
図中、Z0は振動子自身のインピーダンス、Ｚは
気体の摩擦効果を含めたインピーダンスである。 In the figure, Z 0 is the impedance of the vibrator itself, and Z is the impedance including the frictional effect of the gas.
この図から理解できるように、水晶振動子２０
のインピーダンスＺは前述したように気体の圧力
によつて大幅に変化するとともに、△□〇……等
の記号で示すように気体の種類Xe，Ar，He……
等によつても変化の割合が異なつていることがわ
かる。 As you can understand from this diagram, the crystal oscillator 20
As mentioned above, the impedance Z of the gas changes significantly depending on the pressure of the gas, and as indicated by symbols such as △□〇...
It can be seen that the rate of change also differs depending on the factors.
したがつて、第１図で示したように一方の水晶
振動部１０ａには標準のガスGa（例えば空気
（Air））をベローズ１１ａに密封しておき、他方
の水晶振動部１０ｂには外気が自由に出入できる
ような容器１１ｂに設定しておくと、両方の水晶
振動部１０ａ，１０ｂは同一の圧力のもとで動作
することになるが、水晶振動部１０ｂの方は空気
以外のガスGbにも接触することになる。 Therefore, as shown in FIG. 1, one crystal vibrating part 10a is sealed with a standard gas Ga (for example, air) in the bellows 11a, and the other crystal vibrating part 10b is filled with outside air. If the container 11b is set in such a way that it can be freely entered and exited, both crystal vibrating parts 10a and 10b will operate under the same pressure, but the crystal vibrating part 10b is free from gas other than air Gb. You will also come into contact with
そこで、この両者の振動特性のうち、例えば水
晶振動子２０のインピーダンスＺをそれぞれ測定
部１３ａ，１３ｂにおいて測定すると、ガスGa，
Gbの違いにもとづく数値が検出部１４から出力
されるから、この数値から容器１１ｂに流入した
ガスの種類、および組成変化を検出することがで
きる。 Therefore, when the impedance Z of the crystal oscillator 20 is measured in the measurement units 13a and 13b, among the vibration characteristics of the two, for example, the gas Ga,
Since a numerical value based on the difference in Gb is output from the detection unit 14, the type of gas flowing into the container 11b and a change in composition can be detected from this numerical value.
この場合、気体の圧力が変化した場合でも、測
定部１３ａの出力から圧力情報を得ることができ
るので、検出部１４において圧力データも判断の
基準となるように演算すると、ガスの種類の特定
が前記第３図のデータから可能になることはいう
までもない。 In this case, even if the pressure of the gas changes, pressure information can be obtained from the output of the measuring section 13a, so if the pressure data is also calculated in the detection section 14 as a criterion for judgment, the type of gas can be identified. It goes without saying that this is possible from the data shown in FIG.
第４図は、励振部１２ａ，１２ｂの一実施例を
示す回路図である。この図においてＸ−talは水
晶振動子、Ａは増幅器、CF，CVはコンデンサ、
Ｒは抵抗を示す。 FIG. 4 is a circuit diagram showing one embodiment of the excitation sections 12a and 12b. In this diagram, X-tal is a crystal oscillator, A is an amplifier, C F and C V are capacitors,
R indicates resistance.
抵抗Ｒに流れる電流は水晶振動子Ｘ−talのイ
ンピーダンスＺに対応する値となるので、この値
を測定することによつてインピーダンスＺの変化
を知ることができる。 Since the current flowing through the resistor R has a value corresponding to the impedance Z of the crystal resonator X-tal, changes in the impedance Z can be known by measuring this value.
以上の説明から、この発明ではガスGaに対す
るガスGbの粘性や密度の変化を知ることができ
るので、大気の組成変化、つまり、空気以外のガ
スの存在や、酸素分圧の欠乏に関する情報も正確
に得ることが可能になり、酸欠防止、ガス漏れ等
の検出器として好適である。 From the above explanation, with this invention, it is possible to know changes in the viscosity and density of gas Gb relative to gas Ga, so information regarding changes in the composition of the atmosphere, that is, the presence of gases other than air and the lack of oxygen partial pressure, is also accurate. It is suitable as a detector for preventing oxygen deficiency and detecting gas leaks.
なお、水晶振動子２０としては棒状の伸縮振動
を行うもの、または板状のタワミ振動を行うもの
でもよく、他に、セラミツク等からなる圧電素子
も振動子として利用することができる。 Note that the crystal resonator 20 may be a rod-shaped one that performs stretching vibration or a plate-shaped one that performs deflection vibration, and a piezoelectric element made of ceramic or the like may also be used as the resonator.
以上説明したように、この発明のガス検出装置
は圧電振動子がガスの種類によつてその振動特性
が変化する点に着目してガスの種類、および組成
変化を検出するように構成されているので、半導
体センサにみられるようにガスの吸着や、経年変
化によつて検出感度が変化し、検出不能になるこ
とがないという利点がある。
As explained above, the gas detection device of the present invention is configured to detect the type of gas and changes in composition by focusing on the fact that the vibration characteristics of the piezoelectric vibrator change depending on the type of gas. Therefore, there is an advantage that the detection sensitivity does not change due to gas adsorption or aging and become undetectable, as is the case with semiconductor sensors.
また、２個の圧電振動子の相対的な変化を検出
するように構成しているので、ガス圧や、温度特
性の補正が不要になり、検出装置の取扱い、およ
び設置が簡単になるという顕著な効果がある。 In addition, since it is configured to detect relative changes between two piezoelectric vibrators, there is no need to compensate for gas pressure or temperature characteristics, which significantly simplifies the handling and installation of the detection device. It has a great effect.
また、水晶振動子の電力消費量は1μw程度と極
めて少なく、交流電源を用いる必要はないので、
設置場所の制限は小さく、移動も容易であつて、
応用範囲は広いという実用的な効果もある。 In addition, the power consumption of the crystal oscillator is extremely low at around 1μW, so there is no need to use an AC power supply.
There are few restrictions on the installation location, and it is easy to move.
It also has the practical effect of having a wide range of applications.
第１図は、この発明のガス検出装置の概要を示
すブロツク図、第２図ａ，ｂは水晶振動部の一実
施例を示す正面図と側面図、第３図は励振部の一
実施例を示す回路図、第４図は励振部の励振回路
の一例を示す回路図、第５図は従来の圧力検出用
の振動部を示す構造図である。
図中、１０ａ，１０ｂは水晶振動部、１１ａは
ベローズ、１２ａ，１２ｂは励振部、１３ａ，１
３ｂは測定部、１４は検出部、１５は出力部を示
す。
FIG. 1 is a block diagram showing an overview of the gas detection device of the present invention, FIGS. 2a and b are front and side views showing an embodiment of the crystal vibrating section, and FIG. 3 is an embodiment of the excitation section. FIG. 4 is a circuit diagram showing an example of an excitation circuit of an excitation section, and FIG. 5 is a structural diagram showing a conventional vibrating section for pressure detection. In the figure, 10a and 10b are crystal vibrating parts, 11a is a bellows, 12a and 12b are excitation parts, and 13a and 1
3b is a measurement section, 14 is a detection section, and 15 is an output section.
Claims (1)
され、屈曲振動をする第１の圧電振動体と、外気
が出入する容器に設置し、前記第１の圧電振動体
とほぼ同一条件で屈曲振動するように配置されて
いる第２の圧電振動体と、前記第１、および第２
の圧電振動体の電気的インピーダンスをそれぞれ
測定する第１、第２の測定部と、前記第１、第２
の測定部から出力された信号を比較し、前記第２
の圧電振動体に接触している気体の種類、または
組成変化を特定する検出部を備えていることを特
徴とするガス検出装置。1. A first piezoelectric vibrator that is sealed in a standard gas-sealed bellows and vibrates flexurally, and is installed in a container through which outside air enters and exits, and vibrates flexurally under almost the same conditions as the first piezoelectric vibrator. a second piezoelectric vibrator arranged as shown in FIG.
a first and a second measurement unit that respectively measure the electrical impedance of the piezoelectric vibrating body;
The signals output from the second measuring section are compared, and the second
What is claimed is: 1. A gas detection device comprising a detection unit that identifies a change in the type or composition of a gas that is in contact with a piezoelectric vibrating body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9596084A JPS60238742A (en) | 1984-05-14 | 1984-05-14 | Gas detecting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9596084A JPS60238742A (en) | 1984-05-14 | 1984-05-14 | Gas detecting device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60238742A JPS60238742A (en) | 1985-11-27 |
| JPH0358459B2 true JPH0358459B2 (en) | 1991-09-05 |
Family
ID=14151787
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9596084A Granted JPS60238742A (en) | 1984-05-14 | 1984-05-14 | Gas detecting device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60238742A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0484569A1 (en) * | 1990-11-06 | 1992-05-13 | Asea Brown Boveri Ag | Apparatus for measuring sulphur hexafluoride decomposition products |
| CN100465613C (en) * | 2005-06-28 | 2009-03-04 | 上海理工大学 | Method and its device for on-line detecting atmospheric particulate matter concentration |
| JP2007121250A (en) * | 2005-10-31 | 2007-05-17 | Kyocera Kinseki Corp | Sensor for small mass measurement |
| JP5626502B2 (en) * | 2009-01-23 | 2014-11-19 | セイコーエプソン株式会社 | Stress detector |
| DE102018210387B4 (en) * | 2018-06-26 | 2023-03-23 | Robert Bosch Gmbh | Sensor device and method for detecting gases |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5542054A (en) * | 1978-09-19 | 1980-03-25 | Seikosha Co Ltd | Watch with gas detector |
-
1984
- 1984-05-14 JP JP9596084A patent/JPS60238742A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5542054A (en) * | 1978-09-19 | 1980-03-25 | Seikosha Co Ltd | Watch with gas detector |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60238742A (en) | 1985-11-27 |
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| EXPY | Cancellation because of completion of term |