JPH0646181B2 - Infrared carbon dioxide analyzer - Google Patents
Infrared carbon dioxide analyzerInfo
- Publication number
- JPH0646181B2 JPH0646181B2 JP5772288A JP5772288A JPH0646181B2 JP H0646181 B2 JPH0646181 B2 JP H0646181B2 JP 5772288 A JP5772288 A JP 5772288A JP 5772288 A JP5772288 A JP 5772288A JP H0646181 B2 JPH0646181 B2 JP H0646181B2
- Authority
- JP
- Japan
- Prior art keywords
- carbon dioxide
- gas
- sample
- wavelength
- infrared
- 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 - Fee Related
Links
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 title claims description 62
- 229910002092 carbon dioxide Inorganic materials 0.000 title claims description 31
- 239000001569 carbon dioxide Substances 0.000 title claims description 31
- 238000005259 measurement Methods 0.000 claims description 19
- 238000010521 absorption reaction Methods 0.000 claims description 8
- 230000007423 decrease Effects 0.000 claims description 5
- 230000003287 optical effect Effects 0.000 description 6
- 235000013305 food Nutrition 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 230000001678 irradiating effect Effects 0.000 description 3
- 235000021485 packed food Nutrition 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 2
- 230000003385 bacteriostatic effect Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000002778 food additive Substances 0.000 description 1
- 235000013373 food additive Nutrition 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000002503 metabolic effect Effects 0.000 description 1
- 244000005700 microbiome Species 0.000 description 1
- 230000009965 odorless effect Effects 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000002336 sorption--desorption measurement Methods 0.000 description 1
- 230000009967 tasteless effect Effects 0.000 description 1
- 230000036962 time dependent Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
- G01N21/3504—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light for analysing gases, e.g. multi-gas analysis
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、食品パックの中の炭酸ガス濃度を測定する場
合等のように、微量の試料ガスをもって炭酸ガス濃度を
測定するに好適な赤外線式炭酸ガス分析計に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention provides an infrared ray suitable for measuring the carbon dioxide concentration with a small amount of sample gas, such as when measuring the carbon dioxide concentration in a food pack. The present invention relates to a carbon dioxide analyzer.
［従来の技術］ 昨今、食品添加物に対する法的規制の強化及び消費者の
無添加食品指向の流れの中で、食品のガス充填包装が脚
光を浴びている。なかでも、炭酸ガスは無味、無臭、無
色てあって、微生物に対する代謝阻害作用や静菌作用に
基づくシエルフライフの延長の為に広く用いられ、か
つ、かかる包装食品の保存性等の調査研究の為に、それ
に充填されている炭酸ガスの濃度測定が必要とされてい
る。[Prior Art] In recent years, gas-filled packaging of foods has been in the spotlight due to the tightening of legal restrictions on food additives and the trend toward consumer-free foods. Among them, carbon dioxide gas is tasteless, odorless, and colorless, and is widely used for the purpose of prolonging the shelf life based on the metabolic inhibitory action and bacteriostatic action on microorganisms, and the research study on the preservability of such packaged foods. Therefore, it is necessary to measure the concentration of carbon dioxide gas filled in it.
［発明が解決しようとする課題］ しかし、かかる包装食品に充填されている炭酸ガス量が
少量である為、微量の試料ガス（サンプルガス）をもっ
ての濃度測定が余儀無くされ、その為、それに適したガ
ス分析計の開発が急がれていた。[Problems to be Solved by the Invention] However, since the amount of carbon dioxide gas filled in such a packaged food is small, it is unavoidable to measure the concentration with a very small amount of sample gas (sample gas), which is suitable for it. There was an urgent need to develop a gas analyzer.
本発明は、このような背景下において発明されたもので
あって、微量の試料ガス（サンプルガス）をもっての炭
酸ガス濃度測定を正確に行うことができる赤外線式炭酸
ガス分析計を提供しようとするものである。The present invention has been invented under such a background, and an object thereof is to provide an infrared carbon dioxide analyzer capable of accurately measuring the carbon dioxide concentration with a small amount of sample gas (sample gas). It is a thing.
［課題を解決するための手段］ かかる目的を達成する本発明に係る赤外線式炭酸ガス分
析計は、赤外線が照射される試料セルに試料ガスを供給
し、前記試料セルにおける透過光の増減を検出すると共
に、それを増幅せしめて演算処理部に出力することによ
り炭酸ガス濃度を測定し得るように構成された赤外線式
炭酸ガス分析計において、注射器を介してシリンジに注
入される前記試料ガスを、前記試料セル及び圧力センサ
に供給し得るように配設された試料供給管路と、同一光
源からの前記赤外線を、測定波長（炭酸ガスの特性吸収
を示す波長）の赤外線と比較波長（測定ガスに吸収され
ない波長）の赤外線とに分けて両者を交互に前記試料セ
ルに照射せしめる照射手段とを備え、かつ、前記演算処
理部への前記出力を、前記試料ガスの供給時における圧
力変動を前記圧力センサが検出して前記演算処理部へ出
力してから数秒経過後においてするようにしたことを特
徴とするものである。[Means for Solving the Problems] An infrared carbon dioxide analyzer according to the present invention that achieves the above object supplies a sample gas to a sample cell irradiated with infrared rays and detects an increase / decrease in transmitted light in the sample cell. In addition, in the infrared type carbon dioxide analyzer configured to be able to measure the carbon dioxide concentration by amplifying it and outputting it to the arithmetic processing unit, the sample gas injected into the syringe via the syringe, A sample supply pipe line arranged so as to be able to supply to the sample cell and the pressure sensor, and the infrared ray from the same light source as an infrared ray of a measurement wavelength (a wavelength showing characteristic absorption of carbon dioxide gas) and a comparison wavelength (measurement gas) And an irradiation means for alternately irradiating the sample cell with infrared rays having a wavelength not absorbed by the sample gas, and supplying the output to the arithmetic processing unit with the sample gas. The present invention is characterized in that the pressure sensor detects a time-dependent pressure fluctuation and outputs it to the arithmetic processing unit after a few seconds have elapsed.
［実施例］ 以下、本発明に係る実施例について述べると、第１図に
おいて、赤外線を発する光源１はセラミックヒータが用
いられているが、かかる赤外線は、照射手段１４によ
り、測定波長（炭酸ガスの特性吸収を示す波長）の赤外
線と、比較波長（測定ガスに吸収されない波長）の赤外
線とに分けられ、かつ、それらが交互に試料セル４に照
射される。[Examples] Examples of the present invention will be described below. In FIG. 1, a ceramic heater is used as the light source 1 that emits infrared rays. The infrared ray having a characteristic absorption of 1) and the infrared ray having a comparative wavelength (a wavelength not absorbed by the measurement gas) are divided into two, and these are alternately irradiated to the sample cell 4.
すなわち、照射手段１４は、モータ３で駆動回転させ得
るように装着されているフイルタホイール２に、測定波
長（炭酸ガスの特性吸収を示す波長）の赤外線だけを透
過させる光学フイルタ２ａと、比較波長（測定ガスに吸
収されない波長）の赤外線だけを透過させる光学フイル
タ２ｂとを装着しているので、モータ３の一方々向への
回転により、一方の光学フイルタ２ａと他方の光学フイ
ルタ２ｂとを交互に赤外線照射位置へ移動させることが
でき、従って、光源１から発せられる赤外線を、測定波
長（炭酸ガスの特性吸収を示す波長）の赤外線と、比較
波長（測定ガスに吸収されない波長）の赤外線とに分
け、かつ、それらを交互に試料セル４に照射することが
できる。That is, the irradiating means 14 has an optical filter 2a for transmitting only infrared rays of a measurement wavelength (a wavelength showing characteristic absorption of carbon dioxide gas) to the filter wheel 2 mounted so as to be driven and rotated by the motor 3, and a comparison wavelength. Since the optical filter 2b that transmits only infrared rays (wavelength not absorbed by the measurement gas) is mounted, one optical filter 2a and the other optical filter 2b are alternately rotated by rotating the motor 3 in one direction. Therefore, the infrared light emitted from the light source 1 is the infrared light of the measurement wavelength (the wavelength showing the characteristic absorption of carbon dioxide gas) and the infrared light of the comparison wavelength (the wavelength which is not absorbed by the measurement gas). And the sample cell 4 can be alternately irradiated with them.
なお、このようにして、測定波長（炭酸ガスの特性吸収
を示す波長）の赤外線と比較波長（測定ガスに吸収され
ない波長）の赤外線とを交互を照射する一方において、
試料セル４における透過光の増減が受光素子５で検出さ
れ、それが増幅器６で増幅されて演算処理部７へ出力さ
れる。この点については、更に詳細に後述する。In this way, while irradiating the infrared rays of the measurement wavelength (wavelength indicating characteristic absorption of carbon dioxide gas) and the infrared rays of the comparison wavelength (wavelength not absorbed by the measurement gas) alternately,
The increase / decrease in the transmitted light in the sample cell 4 is detected by the light receiving element 5, amplified by the amplifier 6, and output to the arithmetic processing unit 7. This point will be described later in more detail.
次に、試料セル４は、ガス供給口４ａとガス排出口４ｂ
とを有している微小セル（例えば、その容積が約２５μ
ｌといった微小セル）で構成され、更に、注射器１３を
介してシリンジ１０に注入される試料ガスを、試料セル
４及び圧力センサ１１（半導体圧力センサで構成されて
いる。）に供給し得るように試料供給管路８が配設され
ていると共に、シリンジ１０の排出口側にフイルタ９が
装着されている。Next, the sample cell 4 includes a gas supply port 4a and a gas discharge port 4b.
A microcell having, for example, a volume of about 25 μ
(a micro cell such as 1), and the sample gas injected into the syringe 10 via the injector 13 can be supplied to the sample cell 4 and the pressure sensor 11 (which is composed of a semiconductor pressure sensor). A sample supply conduit 8 is provided, and a filter 9 is attached to the outlet side of the syringe 10.
その為、注射器１３を介してシリンジ１０中に、３ｃｃ
以上の微量の試料ガス（包装食品等から採取した炭酸ガ
ス）を注入すると、かかる試料ガスがフイルタ９を通過
し、試料供給管路８を経て圧力センサ１１及び試料セル
４に導かれ、ガス排出口４ｂから大気中に排出される。
これにより、容積が微小の試料セル４内のガスが、かか
る試料ガスにより瞬時に置換される。Therefore, 3 cc in the syringe 10 via the syringe 13.
When a small amount of the above sample gas (carbon dioxide gas collected from packaged foods, etc.) is injected, the sample gas passes through the filter 9, is guided to the pressure sensor 11 and the sample cell 4 via the sample supply pipe line 8, and is discharged. It is discharged into the atmosphere through the outlet 4b.
As a result, the gas in the sample cell 4 having a small volume is instantly replaced by the sample gas.
更に、圧力センサ１１は、上述のように、試料ガスが、
試料供給管路８を経て圧力センサ１１及び試料セル４に
導かれると、その時（試料ガスの供給時）における圧力
変動を検出して演算処理部７へ出力し得るように装着さ
れ、かつ、かかる出力後、数秒経過した時点において、
増幅器６から演算処理部７に出力される。Further, as described above, the pressure sensor 11 detects that the sample gas is
When it is guided to the pressure sensor 11 and the sample cell 4 via the sample supply pipe line 8, it is mounted so as to detect the pressure fluctuation at that time (when supplying the sample gas) and output it to the arithmetic processing unit 7, and After a few seconds have passed after the output,
It is output from the amplifier 6 to the arithmetic processing unit 7.
すなわち、照射手段１４により、測定波長（炭酸ガスの
特性吸収を示す波長）の赤外線と比較波長（測定ガスに
吸収されない波長）の赤外線とが交互に照射される試料
セル４における透過光の増減が受光素子５で検出され、
それが増幅器６で増幅されて演算処理部７へ出力され
る。この態様が第２図及び第３図において示されてい
る。That is, the irradiation means 14 alternately irradiates infrared rays of a measurement wavelength (a wavelength showing characteristic absorption of carbon dioxide gas) and infrared rays of a comparison wavelength (a wavelength not absorbed by the measurement gas), thereby increasing or decreasing the transmitted light in the sample cell 4. Detected by the light receiving element 5,
It is amplified by the amplifier 6 and output to the arithmetic processing unit 7. This aspect is shown in FIGS. 2 and 3.
なお、演算処理部７には、前回の測定値が保持されてい
るが、圧力センサ１１は、試料ガスの供給時の圧力変動
を瞬時に検出して演算処理部７へ出力する。これが第３
図においてＡで示されている。かかる出力値は、一時的
に高くなるが、その後、次第に低下されて元の値（大気
圧）より少し高い値になる。この時点が第３図において
Ｂで示されている。Although the previous measurement value is held in the arithmetic processing unit 7, the pressure sensor 11 instantaneously detects the pressure fluctuation when the sample gas is supplied and outputs it to the arithmetic processing unit 7. This is the third
This is indicated by A in the figure. The output value temporarily increases, but then gradually decreases to a value slightly higher than the original value (atmospheric pressure). This point is indicated by B in FIG.
続いて、Ｂから０．５〜３秒、好ましくは１秒経過する
と、すなわち、圧力センサ１１が、試料ガスの供給時の
圧力変動を検出し瞬時に演算処理部７に出力した時点か
ら、数秒経過した時点（第３図においてＣで示されてい
る大気圧になった時点）において増幅器６から出力さ
れ、かつ、それが演算処理部７に保持され、この保持さ
れた値が演算処理部７のリニアライズ回路（図示されて
いない）において炭酸ガス濃度と一致した値となって表
示出力部１２に出力される。Then, when 0.5 to 3 seconds, preferably 1 second elapses from B, that is, several seconds from the time when the pressure sensor 11 detects the pressure fluctuation during the supply of the sample gas and instantaneously outputs it to the arithmetic processing unit 7. At the time point when it has elapsed (at the time point when the atmospheric pressure indicated by C in FIG. 3 is reached), it is output from the amplifier 6 and is stored in the arithmetic processing unit 7, and the held value is stored in the arithmetic processing unit 7. Is output to the display output unit 12 as a value that matches the carbon dioxide concentration in a linearizing circuit (not shown).
このように、本発明に係るガス分析計は、注射器１３等
を介して微量の試料ガスを供給し得るようにしていると
共に照射手段１４により、同一光源からの赤外線を、測
定波長（炭酸ガスの特性吸収を示す波長）の赤外線と、
比較波長（測定ガスに吸収されない波長）の赤外線とに
分けて、それらを交互に試料セル４に照射するように
し、しかも、試料セル４における透過光の増減を検出し
て、それを増幅せしめて演算処理部７に出力すること
を、試料ガスの供給時における圧力変動を圧力センサ１
１が検出して演算処理部７へ出力してから数秒経過後、
すなわち、大気圧になった時点においてするようにして
いる。As described above, the gas analyzer according to the present invention is configured to be able to supply a small amount of sample gas via the injector 13 and the like, and at the same time, the irradiation means 14 emits infrared rays from the same light source to the measurement wavelength (of carbon dioxide gas). Infrared of wavelength) which shows characteristic absorption,
It is divided into infrared rays of a comparative wavelength (wavelength not absorbed by the measurement gas) and these are alternately irradiated to the sample cell 4, and moreover, increase / decrease of transmitted light in the sample cell 4 is detected and amplified. The output to the arithmetic processing unit 7 is the pressure fluctuation of the pressure sensor 1 when the sample gas is supplied.
After several seconds have passed since the detection by 1 and output to the arithmetic processing unit 7,
That is, this is done when the atmospheric pressure is reached.
その為、炭酸ガス特有の吸・脱着性、或いは、試料セル
４のガス供給口及びガス排出口からの試料ガスの拡散等
に起因する、試料セル４内の試料濃度変化による読み取
り誤差を無くすることができて微量の試料ガスをもって
の炭酸ガス濃度測定を正確に行うことができ、従って、
食品パック中の炭酸ガス農を測定する場合において好適
である。Therefore, a reading error due to a change in the sample concentration in the sample cell 4 caused by the adsorption / desorption characteristic of carbon dioxide gas or the diffusion of the sample gas from the gas supply port and the gas discharge port of the sample cell 4 is eliminated. It is possible to accurately measure the carbon dioxide concentration with a small amount of sample gas, and therefore,
It is suitable for measuring carbon dioxide production in food packs.
［発明の効果］ 上述の如く、本発明によると、試料セル内の試料ガス濃
度変化による測定誤差を無くすることができて微量の試
料ガスをもっての炭酸ガス濃度測定を正確に行うことが
でき、従って、食品パック中の炭酸ガス濃度を測定する
場合において好適な赤外線式炭酸ガス分析計を得ること
ができる。[Advantages of the Invention] As described above, according to the present invention, it is possible to eliminate a measurement error due to a change in the sample gas concentration in the sample cell, and to accurately perform the carbon dioxide concentration measurement with a small amount of sample gas. Therefore, an infrared type carbon dioxide analyzer suitable for measuring the carbon dioxide concentration in the food pack can be obtained.
第１図は赤外線式炭酸ガス分析計の構成を概略的に示す
図、第２図は増幅器６の出力状態を示す図、第３図は圧
力センサ１１の出力状態を示す図である。 １は赤外線を発する光源、２ａは測定波長の赤外線だけ
を透過させる光学フイルタ、２ｂは比較波長の赤外線だ
けを透過させる光学フイルタ、４は試料セル、５は受光
素子、６は増幅器、７は演算処理部、８は試料供給管
路、１０はシリンジ、１１は圧力センサ、１３は注射
器、１４は照射手段FIG. 1 is a diagram schematically showing a configuration of an infrared carbon dioxide analyzer, FIG. 2 is a diagram showing an output state of an amplifier 6, and FIG. 3 is a diagram showing an output state of a pressure sensor 11. Reference numeral 1 is a light source that emits infrared rays, 2a is an optical filter that transmits only infrared rays of a measurement wavelength, 2b is an optical filter that transmits only infrared rays of a comparison wavelength, 4 is a sample cell, 5 is a light receiving element, 6 is an amplifier, 7 is an operation Processing unit, 8 is a sample supply line, 10 is a syringe, 11 is a pressure sensor, 13 is a syringe, and 14 is irradiation means.
Claims (1)
供給し、前記試料セルにおける透過光の増減を検出する
と共に、それを増幅せしめて演算処理部に出力すること
により炭酸ガス濃度を測定し得るように構成された赤外
線式炭酸ガス分析計において、注射器を介してシリンジ
に注入される前記試料ガスを、前記試料セル及び圧力セ
ンサに供給し得るように配設された試料供給管路と、同
一光源からの前記赤外線を、測定波長（炭酸ガスの特性
吸収を示す波長）の赤外線と比較波長（測定ガスに吸収
されない波長）の赤外線とに分けて両者を交互に前記試
料セルに照射せしめる照射手段とを備え、かつ、前記演
算処理部への前記出力を、前記試料ガスの供給時におけ
る圧力変動を前記圧力センサが検出して前記演算処理部
へ出力してから数秒経過後においてするようにしたこと
を特徴とする赤外線式炭酸ガス分析計。1. A carbon dioxide concentration is measured by supplying a sample gas to a sample cell irradiated with infrared rays, detecting an increase / decrease in transmitted light in the sample cell, amplifying it, and outputting it to an arithmetic processing unit. In an infrared carbon dioxide analyzer configured to be capable of, the sample gas injected into the syringe via a syringe, and a sample supply conduit arranged so as to be able to supply the sample cell and the pressure sensor. , The infrared ray from the same light source is divided into an infrared ray of a measurement wavelength (a wavelength showing characteristic absorption of carbon dioxide gas) and an infrared ray of a comparison wavelength (a wavelength not absorbed by the measurement gas), and both are alternately irradiated to the sample cell. An irradiation unit, and the output to the arithmetic processing unit is detected after the pressure sensor detects a pressure fluctuation during the supply of the sample gas and is output to the arithmetic processing unit. Infrared carbon dioxide analyzer, characterized in that so as to after elapse.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5772288A JPH0646181B2 (en) | 1988-03-10 | 1988-03-10 | Infrared carbon dioxide analyzer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5772288A JPH0646181B2 (en) | 1988-03-10 | 1988-03-10 | Infrared carbon dioxide analyzer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01229941A JPH01229941A (en) | 1989-09-13 |
| JPH0646181B2 true JPH0646181B2 (en) | 1994-06-15 |
Family
ID=13063834
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5772288A Expired - Fee Related JPH0646181B2 (en) | 1988-03-10 | 1988-03-10 | Infrared carbon dioxide analyzer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0646181B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4948145B2 (en) * | 2006-12-13 | 2012-06-06 | 日本信号株式会社 | Gas detector |
| KR100871909B1 (en) * | 2007-06-15 | 2008-12-05 | 한국표준과학연구원 | Infrared gas detector having a selective detector module |
| SG11201701015QA (en) | 2014-08-29 | 2017-03-30 | Univ Tohoku | Optical concentration measuring method |
| KR102127636B1 (en) * | 2018-09-21 | 2020-06-29 | 한국표준과학연구원 | Infrared Light Emitting Diode And Infrared Gas Sensor |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH055483Y2 (en) * | 1987-05-06 | 1993-02-12 |
-
1988
- 1988-03-10 JP JP5772288A patent/JPH0646181B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01229941A (en) | 1989-09-13 |
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