JPH0769256B2 - Crystal oscillation type moisture meter - Google Patents
Crystal oscillation type moisture meterInfo
- Publication number
- JPH0769256B2 JPH0769256B2 JP62154145A JP15414587A JPH0769256B2 JP H0769256 B2 JPH0769256 B2 JP H0769256B2 JP 62154145 A JP62154145 A JP 62154145A JP 15414587 A JP15414587 A JP 15414587A JP H0769256 B2 JPH0769256 B2 JP H0769256B2
- Authority
- JP
- Japan
- Prior art keywords
- gas supply
- sample gas
- flow rate
- cell
- crystal oscillation
- 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
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- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
- Sampling And Sample Adjustment (AREA)
- Oscillators With Electromechanical Resonators (AREA)
Description
【発明の詳細な説明】 （イ）産業上の利用分野 この発明は水晶発振式水分計に関する。さらに詳しくは
水晶発振式センサを内蔵した湿度測定セルを用いて気体
中の水分濃度を測定する水分計に関する。DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a crystal oscillation type moisture meter. More specifically, the present invention relates to a moisture meter that measures a moisture concentration in a gas by using a humidity measuring cell having a built-in crystal oscillation type sensor.
（ロ）従来の技術 水晶発振式センサにより気体中の微量水分濃度を測定し
うる水晶発振式水分計としては、第２図に示すごとく、
試料ガス供給部（21）から第１流量制御部（31）、排気
流路c1へ切換接続しうる第１三方電磁弁（41）をこの順
に介して延設され水晶発振式センサ（51）内蔵湿度測定
セル（61）に接続される試料ガス供給流路（a1）と、該
流路（a1）の上記試料ガス供給部（21）と第１流量制御
部（31）との間の流路から分岐構成され、乾燥部を有す
るゼロガス発生器（71）、第２流量制御部（81）、排気
流路（c2）に切換接続しうる第２三方電磁弁（91）をこ
の順に管路接続して上記湿度測定セル（61）に延設され
るゼロガス（基準ガス）供給流路（b1）とから構成され
るものが知られている。上記構成の水晶発振式水分計に
おいて試料ガス中の水分の測定は、上記第１三方電磁弁
（41）および第２三方電磁弁（91）の切換えにより、湿
度測定セル内に測定対象の試料ガスまたはゼロガス（基
準ガス）を一定時間ずつ交互に導入して行われている。(B) Conventional Technology As a crystal oscillation type moisture meter capable of measuring a trace amount of water concentration in a gas by a crystal oscillation type sensor, as shown in FIG.
A crystal oscillation type sensor (51) which is extended through a sample gas supply section (21), a first flow rate control section (31) and a first three-way solenoid valve (41) which can be switched and connected to the exhaust flow path c 1 in this order. Between the sample gas supply channel (a 1 ) connected to the built-in humidity measurement cell (61) and between the sample gas supply section (21) and the first flow rate control section (31) of the channel (a 1 ). A zero gas generator (71) having a drying section, a second flow rate control section (81), and a second three-way solenoid valve (91) that can be switchably connected to the exhaust flow path (c 2 ). It is known that a zero gas (reference gas) supply flow path (b 1 ) is connected in order to the humidity measurement cell (61) and extended to the humidity measurement cell (61). In the crystal oscillation type moisture meter having the above-mentioned configuration, the moisture content in the sample gas is measured by switching the first three-way solenoid valve (41) and the second three-way solenoid valve (91) to the sample gas to be measured in the humidity measuring cell. Alternatively, zero gas (reference gas) is alternately introduced at regular intervals.
（ハ）発明が解決しようとする問題点 上記のごとき水分計では水晶発振式センサの水分に対す
る感度が高いのが大きな長所であり、微量の水分測定に
は適しているが、しかしながら、濃度の高い水分測定に
は適していない。これは上記センサが高濃度水分に対し
ヒステリシス現象を示すことと、基準ガスから試料ガス
への切換えに伴う過渡特性としてオーバーシュート現象
を示すからである。従って上記水分計により精度良く測
定できうる水分濃度領域が、数ppmから1,000ppm程度の
水分濃度領域に限定されている。なお精度が悪い測定で
良いときは従来法でも3,000〜5,000ppm近くまで測定は
可能であるが、その精度は濃度に対し±20％の誤差を含
むものである。しかし１％近い水分濃度に対しては±50
％近くまで低下するなどの問題がある。(C) Problems to be Solved by the Invention In the moisture meter as described above, the crystal oscillator type sensor has a high sensitivity to moisture, which is a great advantage, and is suitable for measuring a small amount of moisture, but the concentration is high. Not suitable for moisture determination. This is because the sensor exhibits a hysteresis phenomenon with respect to high-concentration moisture and an overshoot phenomenon as a transient characteristic accompanying switching from the reference gas to the sample gas. Therefore, the moisture concentration range that can be accurately measured by the moisture meter is limited to the moisture concentration range of several ppm to 1,000 ppm. When the accuracy is low, the conventional method can measure up to 3,000 to 5,000 ppm, but the accuracy includes an error of ± 20% with respect to the concentration. However, ± 50 for water concentration close to 1%
There is a problem such as a drop in the percentage.
この発明はかかる状況に鑑みなされたものであり、１％
程度の高濃度水分をヒステリシス現象およびオーバーシ
ュート現象を示すことなく精度良くできかつ数ppm程度
の微量水分も測定可能な水晶発振式水分計を提供しよう
とするものである。The present invention has been made in view of such circumstances, and is 1%
It is an object of the present invention to provide a crystal oscillation type moisture meter capable of accurately measuring a high-concentration water of a high degree without showing a hysteresis phenomenon and an overshoot phenomenon and measuring a trace amount of water of a few ppm.
（ニ）問題点を解決するための手段 かくしてこの発明によれば、基準ガス供給部から第１流
量制御部を介して水晶発振式センサ内蔵湿度測定セルに
延設される基準ガス供給流路と、試料ガス供給部から第
２流量制御部を介して延設され、上記基準ガス供給流路
の第１流量制御部と上記セルとの間に管路接続される試
料ガス供給流路と、該試料ガス供給流路の第２流量制御
部の後段に付設され排気流路へ切換接続しうる三方弁か
らなり、基準ガス供給流路によって基準ガスを測定セル
へ常時流し、測定時に試料ガスが基準ガスとともに前記
セルに流れるよう前記三方弁を切換えることを特徴とす
る水晶発振式水分計が提供される。(D) Means for Solving the Problems Thus, according to the present invention, a reference gas supply passage extending from the reference gas supply unit to the crystal oscillation type sensor built-in humidity measuring cell via the first flow rate control unit is provided. A sample gas supply channel extending from the sample gas supply section via a second flow rate control section and connected in pipeline between the first flow rate control section of the reference gas supply channel and the cell; It consists of a three-way valve that is attached after the second flow rate control unit of the sample gas supply channel and can be switched and connected to the exhaust channel, and the reference gas is always supplied to the measurement cell by the reference gas supply channel. There is provided a quartz oscillation type moisture meter characterized in that the three-way valve is switched so as to flow with gas into the cell.
この発明は、試料ガス供給流路が水晶発振式センサ内蔵
湿度測定セル手前で基準ガス供給流路に管路接続され、
これにより上記セルに連続して供給される基準ガスに、
測定対象の試料ガスが所望の混合比で添加されることを
可能にして、高濃度の試料ガスを希釈して測定できうる
ように構成されたことを特徴とする。In this invention, the sample gas supply channel is connected to the reference gas supply channel in front of the crystal oscillation type sensor built-in humidity measuring cell,
By this, the reference gas continuously supplied to the cell,
The sample gas to be measured can be added at a desired mixing ratio, and the sample gas of high concentration can be diluted and measured.
この発明において湿度測定セルに設定される水晶発振式
センサは、通常の水晶発振式の湿度センサと同様のもの
が用いられる。In the present invention, the crystal oscillation type sensor set in the humidity measuring cell is the same as a normal crystal oscillation type humidity sensor.
この発明の基準ガス供給流路および試料ガス供給流路に
それぞれ設定される第１および第２の流量制御部は、通
常の流量調整器を用いて構成されていてもよい。The first and second flow rate control units respectively set in the reference gas supply channel and the sample gas supply channel of the present invention may be configured using a normal flow rate regulator.
この発明の試料ガス供給流路に設定される三方弁は、通
常の三方電磁弁が好ましい。該三方弁は試料ガスを上記
湿度測定セルに導入するか該流路外に放出するかのいず
れかに切換えるよう作動する。上記三方弁は第２流量制
御部と上記測定セルとのあいだの流路に設定されること
が好ましい。The three-way valve set in the sample gas supply channel of the present invention is preferably an ordinary three-way solenoid valve. The three-way valve operates to switch between introducing the sample gas into the humidity measuring cell and discharging the sample gas out of the flow path. The three-way valve is preferably set in the flow path between the second flow rate control unit and the measurement cell.
この発明に用いられる基準ガスは、湿分を含有しないゼ
ロガスを意味し、従って基準ガス供給部には除湿手段が
設けられることが好ましい。該除湿手段としては除湿能
を有して接触する気体中の湿分を除去しうるよう構成さ
れるものであればよく、例えば乾燥剤等を充填した通常
の除湿管等が挙げられる。また、上記基準ガス供給部は
独立して設定されてもよいが、試料ガス供給部と共通し
て設定されるものであってもよい。この場合、試料ガス
供給部から延設される試料ガス供給流路を分岐構成し、
該分岐流路を上記のごとき除湿手段に管路接続し、さら
に該除湿手段から基準ガス供給流路を延設するよう構成
される。The reference gas used in the present invention means a zero gas that does not contain moisture, and therefore it is preferable that the reference gas supply unit be provided with a dehumidifying means. The dehumidifying means may have any dehumidifying ability and can remove moisture in the gas with which it comes into contact, and examples thereof include a normal dehumidifying tube filled with a desiccant or the like. The reference gas supply unit may be set independently, but may be set in common with the sample gas supply unit. In this case, the sample gas supply channel extending from the sample gas supply unit is branched and configured,
The branch channel is connected to the dehumidifying means as described above by a pipeline, and the reference gas supply channel is extended from the dehumidifying means.
この発明の基準ガス供給流路は、上記試料ガス供給流路
における第２流量制御部と測定セルとの間の流路に管路
接続されるが、さらに上記三方弁と測定セルとの間の流
路が好ましい。またこの基準ガス供給流路には、必要に
応じて上記試料ガス供給流路に設定される三方弁と同様
の弁が設定されていてもよい。The reference gas supply passage of the present invention is pipe-connected to the passage between the second flow rate control unit and the measurement cell in the sample gas supply passage, but further between the three-way valve and the measurement cell. Channels are preferred. A valve similar to the three-way valve set in the sample gas supply channel may be set in the reference gas supply channel, if necessary.
（ホ）作用 この発明によれば、調節された流量で基準ガス供給部か
ら湿度測定セルまで移送される基準ガスに、予め調節さ
れた流量で移送される試料ガスが、上記セル手前で合流
され、所定の割合に希釈された試料ガスが上記測定セル
に導入されて、該希釈試料ガスについてその水分濃度
が、セルに内蔵された水晶発振式センサにより測定され
る。(E) Action According to the present invention, the reference gas transferred from the reference gas supply unit to the humidity measuring cell at the adjusted flow rate is combined with the sample gas transferred at the preset flow rate before the cell. A sample gas diluted at a predetermined ratio is introduced into the measurement cell, and the water concentration of the diluted sample gas is measured by a crystal oscillation sensor incorporated in the cell.
以下実施例によりこの発明を詳細に説明するが、これに
よりこの発明は限定されるものではない。Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto.
（ヘ）実施例 第１図はこの発明の水晶発振式水分計の一例の構成説明
図である。図において水晶発振式水分計（１）は、試料
ガス供給部（２）から流量調節器（３）および三方電磁
弁（４）をこの順に介して水晶発振式センサ（５）内蔵
湿度測定セル（６）に延設される試料ガス供給流路
（ａ）と、上記試料ガス供給流路（ａ）の試料ガス供給
部（２）と流量調節器（３）との間の分岐部（イ）か
ら、ゼロガス生成器（７）および流量調節器（８）をこ
の順に介して、前記試料ガス供給流路（ａ）の三方電磁
弁（４）と湿度測定セル（６）との間の合流部（ロ）に
接続されるゼロガス供給流路（ｂ）とから主として構成
されている。上記三方電磁弁（４）の残る１つはバイパ
ス（ｃ）に接続され該電磁弁の作動により、試料ガスの
供給は湿度測定セル（６）側またはバイパス（ｃ）側に
一定時間毎に切換えられるように構成されている。また
ゼロガス生成器（７）には乾燥剤が充填されており、該
乾燥剤により試料ガス中の水分が除去されてゼロガスが
生成される。なお、湿度測定セル（６）には図示しない
水分濃度演算部が設定されており、また該セルには図示
しないドレインへの流路が設定されている。なお、水晶
発振式センサ（５）は1,000ppmまでの水分濃度の測定が
可能なものである。(F) Embodiment FIG. 1 is a structural explanatory view of an example of a crystal oscillation type moisture meter of the present invention. In the figure, a crystal oscillation type moisture meter (1) includes a humidity measuring cell (5) with a built-in crystal oscillation type sensor (5) from a sample gas supply section (2) through a flow rate controller (3) and a three-way solenoid valve (4) in this order. 6) A sample gas supply channel (a) extended to the sample gas supply channel (a), and a branch section (a) between the sample gas supply section (2) and the flow rate controller (3) of the sample gas supply channel (a). Through the zero gas generator (7) and the flow rate controller (8) in this order, the confluence part between the three-way solenoid valve (4) and the humidity measuring cell (6) of the sample gas supply channel (a). It is mainly composed of a zero gas supply channel (b) connected to (b). The remaining one of the three-way solenoid valves (4) is connected to the bypass (c), and the supply of the sample gas is switched to the humidity measuring cell (6) side or the bypass (c) side at regular intervals by the operation of the solenoid valve. It is configured to be. The zero gas generator (7) is filled with a desiccant, and the desiccant removes moisture in the sample gas to generate zero gas. A moisture concentration calculating unit (not shown) is set in the humidity measuring cell (6), and a flow path to a drain (not shown) is set in the cell. The crystal oscillation type sensor (5) can measure the water concentration up to 1,000 ppm.
上記のごとく構成された水晶発振式水分計（１）の作動
を説明する。該水分計において三方電磁弁をバイパス側
に切換設定することにより、試料ガスは試料ガス供給部
→流量調節器→三方電磁弁→バイパスに移送されてお
り、一方上記試料ガスの一部は試料ガス供給流路から分
岐部→ゼロガス生成器→流量調節器→合流部→湿度測定
セルの順に移送されて、さらに該セルからドレインに放
流されている。上記構成により水晶発振式センサには常
時ゼロガスが接触しているが、測定時には前記三方電磁
弁が切換えられて試料ガス供給部→流量調節部→三方電
磁弁→湿度測定セルをこの順に接続する試料ガス供給流
路が構成されるが、このとき該試料ガス供給流路を移送
される試料ガスは、該流路の合流部でゼロガス供給流路
を移送されるゼロガスと合流され、試料ガスおよびゼロ
ガスからなる混合ガスが湿度測定セル内に導入されるこ
ととなる。このとき試料ガス供給流路の流量調節器とゼ
ロガス供給流路の流量調節器とを調節することによっ
て、湿度測定セルに所定の混合比率からなる上記混合ガ
スを導入することができる。例えば試料ガスとゼロガス
との流量比率を1:9に設定すれば、湿度測定セルに導入
される混合ガス中の水分濃度は、1/10に希釈されること
になり、また同じく1:4に設定すれば1/5に希釈されるこ
ととなる。従って用いている水晶発振式センサの感度か
ら、上記例の場合前者では測定対象の試料ガスが10,000
ppm程度、後者では5,000ppm程度の高濃度水分を含有す
るものであっても充分に測定することができる。希釈率
は上記のものに限定されず、センサの感度との関係から
任意に設定することができる。また希釈率を小さくすれ
ば、従来のものと基本的には変わらないので、2ppm程度
の水分濃度も測定できる。従ってこの発明の水分計は広
範囲の水分濃度を有する試料ガスについて測定すること
ができる。The operation of the crystal oscillation type moisture meter (1) configured as described above will be described. By switching the three-way solenoid valve to the bypass side in the moisture meter, the sample gas is transferred to the sample gas supply unit → flow rate controller → three-way solenoid valve → bypass, while part of the sample gas is the sample gas. It is transferred from the supply flow path in the order of branching section → zero gas generator → flow rate controller → merging section → humidity measuring cell, and further discharged from the cell to the drain. With the above configuration, zero gas is always in contact with the crystal oscillation type sensor, but at the time of measurement, the three-way solenoid valve is switched to connect the sample gas supply section → flow rate control section → three-way solenoid valve → humidity measurement cell in this order. A gas supply channel is formed. At this time, the sample gas transferred through the sample gas supply channel is merged with the zero gas transferred through the zero gas supply channel at the confluence part of the channel, and the sample gas and the zero gas are combined. The mixed gas consisting of is introduced into the humidity measuring cell. At this time, by adjusting the flow rate controller of the sample gas supply channel and the flow rate controller of the zero gas supply channel, the mixed gas having a predetermined mixing ratio can be introduced into the humidity measuring cell. For example, if the flow rate ratio between sample gas and zero gas is set to 1: 9, the water concentration in the mixed gas introduced into the humidity measurement cell will be diluted to 1/10, and also to 1: 4. If set, it will be diluted to 1/5. Therefore, from the sensitivity of the crystal oscillation type sensor used, in the case of the above example, the sample gas to be measured is 10,000
Even in the case of containing high-concentration water of about ppm, in the latter case, about 5,000 ppm, it can be sufficiently measured. The dilution rate is not limited to the above, and can be set arbitrarily according to the sensitivity of the sensor. Also, if the dilution rate is made small, it is basically the same as the conventional one, so a water concentration of about 2 ppm can also be measured. Therefore, the moisture meter of the present invention can measure sample gases having a wide range of moisture concentrations.
（ト）発明の効果 この発明によれば、試料ガスを所定の濃度に希釈して測
定できるので、０〜2ppm程度から０〜10,000ppm程度ま
での水分濃度が測定できる。試料ガスおよび基準ガスを
交互に導入する必要がなく、基準ガスを常時流した状態
で試料ガスの混合・測定ができるので、従来よりもシン
プルな構成とすることができる。高濃度に水分を含有す
る試料ガスについてのオーバーシュートおよびヒステリ
シスを低減することができ、測定の精度が向上する。(G) Effect of the Invention According to the present invention, since the sample gas can be diluted to a predetermined concentration for measurement, the water concentration from about 0 to 2 ppm to about 0 to 10,000 ppm can be measured. Since it is not necessary to alternately introduce the sample gas and the reference gas, and the sample gas can be mixed and measured while the reference gas is constantly flowing, the configuration can be simpler than in the past. It is possible to reduce the overshoot and the hysteresis for the sample gas containing a high concentration of water, and improve the measurement accuracy.
第１図はこの発明の水晶発振式水分計の一例の構成説明
図、第２図は従来例の第１図相当図である。 （２）……試料ガス供給部、（３）（８）……流量調節
器、（４）……三方電磁弁、（５）……水晶発振式セン
サ、（６）……湿度測定セル、（７）……ゼロガス生成
器、（ａ）……試料ガス供給流路、（ｂ）……ゼロガス
供給流路、（ｃ）……バイパス。FIG. 1 is a structural explanatory view of an example of a crystal oscillation type moisture meter of the present invention, and FIG. 2 is a view corresponding to FIG. 1 of a conventional example. (2) ... Sample gas supply unit, (3) (8) ... Flow rate controller, (4) ... Three-way solenoid valve, (5) ... Crystal oscillation sensor, (6) ... Humidity measuring cell, (7) ... Zero gas generator, (a) ... Sample gas supply flow path, (b) ... Zero gas supply flow path, (c) ... Bypass.
Claims (1)
て水晶発振式センサ内蔵湿度測定セルに延設される基準
ガス供給流路と、試料ガス供給部から第２流量制御部を
介して延設され、上記基準ガス供給流路の第１流量制御
部と上記セルとの間に管路接続される試料ガス供給路
と、該試料ガス供給流路の第２流量制御部の後段に付設
され排気流路へ切換接続しうる三方弁からなり、基準ガ
ス供給流路によって基準ガスを測定セルへ常時流し、測
定時に試料ガスが基準ガスとともに前記セルに流れるよ
う前記三方弁を切換えることを特徴とする水晶発振式水
分計。1. A reference gas supply passage extending from a reference gas supply unit to a humidity measuring cell with a built-in crystal oscillation type sensor via a first flow rate control unit, and a sample gas supply unit via a second flow rate control unit. And a sample gas supply path that is connected between the first flow rate control unit of the reference gas supply flow path and the cell, and a second flow rate control unit of the sample gas supply flow path. It consists of an attached three-way valve that can be switched and connected to the exhaust flow path.The reference gas supply flow path allows the reference gas to constantly flow into the measurement cell, and the three-way valve is switched so that the sample gas flows into the cell along with the reference gas during measurement. Characteristic quartz oscillator type moisture meter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62154145A JPH0769256B2 (en) | 1987-06-19 | 1987-06-19 | Crystal oscillation type moisture meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62154145A JPH0769256B2 (en) | 1987-06-19 | 1987-06-19 | Crystal oscillation type moisture meter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63317743A JPS63317743A (en) | 1988-12-26 |
| JPH0769256B2 true JPH0769256B2 (en) | 1995-07-26 |
Family
ID=15577856
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62154145A Expired - Lifetime JPH0769256B2 (en) | 1987-06-19 | 1987-06-19 | Crystal oscillation type moisture meter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0769256B2 (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5922512Y2 (en) * | 1981-10-28 | 1984-07-05 | 加野 元 | Dust weight concentration measuring device using piezoelectric crystal vibration method |
| JPS5924252A (en) * | 1982-07-30 | 1984-02-07 | Shimadzu Corp | Crystal oscillation moisture meter system |
-
1987
- 1987-06-19 JP JP62154145A patent/JPH0769256B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63317743A (en) | 1988-12-26 |
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