JP2011013073A

Movatterモバイル変換

Info

Publication number: JP2011013073A
Application number: JP2009156871A
Authority: JP
Inventors: Yutaka Iizuka; 豊飯塚; Shigenori Hayashi; 繁徳林
Original assignee: Tsukasa Sokken Co Ltd
Current assignee: Tsukasa Sokken Co Ltd
Priority date: 2009-07-01
Filing date: 2009-07-01
Publication date: 2011-01-20
Anticipated expiration: 2029-07-01
Also published as: JP5804619B2

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting element light intensity compensation technology in an opacimeter capable of compensating a light emission quantity of an LED quickly without using a temperature sensing element, and without requiring an individual temperature characteristic to each LED, and capable of determining directly the light emission quantity of the LED corresponding to a temperature change.SOLUTION: In the light emitting element 4 light intensity compensating device in the opacimeter 1 constituted so that light from the light emitting element 4 forming an optical path for measurement reaching a light receiving element for measurement through a measuring chamber 3 into which exhaust gas 21 which is a measuring object is introduced is transmitted through the exhaust gas 21 in the measuring chamber 3, and received by the light receiving element for measurement, a light receiving element 12 for reference is arranged on a position where emitted light from the light emitting element 4 is received bypassing the measuring chamber 3.

Description

Translated fromJapanese

この発明はオパシメータ（透過式スモークメータ）における発光素子の発光光度補償装置に関するものである。
オパシメータは、測定室に導入された排ガスの粒状物質の濃度を光の減衰量で測定する装置である。The present invention relates to a luminous intensity compensation device for a light emitting element in an opacimeter (transmission type smoke meter).
The opacimeter is a device that measures the concentration of particulate matter in the exhaust gas introduced into the measurement chamber by the amount of attenuation of light.

オパシメータ１０１は図４に示すように、測定室３を挟んで向かい合った発光素子４と受光素子５により測定光路が形成され、測定室３内に被測定対象である排ガス２１を導入し、その排ガス２１中に発光素子４からの光を透過させて受光素子５で受光して計測し排ガス２１内の粒状物質が光を吸収する量を検出し、減衰された光量から排ガスの光吸収係数（ｍ^−１）を算出する。排ガスの粒状物質が光を吸収した量を光吸収係数（Ｋ）と呼び、減衰光との関係はベア・ランベルト法則として広く知られている。
Ｋ＝−（１／Ｌａ）・｛ｌn（Ｉ／Ｉ_０）｝（１式）ただしＫ：光吸収係数（１／ｍ）
Ｌａ :有効光路長さ（ｍ）
Ｉ :排ガスがあるときの光量
Ｉ_０：排ガスが無いときの光量
Ｉ／Ｉ_０ :排ガスの透過率
発光素子４の発光量は周囲温度に影響される場合がある。例えば発光素子４をＬＥＤ（発光ダイオード）で構成した場合には、ＬＥＤの発光量はＬＥＤの周囲温度が高くなると大きく減少し、温度が低くなると増加することは広く知られていて測定値の温度補償をする必要がある。As shown in FIG. 4, theopacimeter 101 forms a measurement optical path by thelight emitting element 4 and thelight receiving element 5 facing each other across the measurement chamber 3, and introduces theexhaust gas 21 to be measured into the measurement chamber 3. 21, the light from thelight emitting element 4 is transmitted, received by thelight receiving element 5 and measured, the amount of the particulate matter in theexhaust gas 21 absorbing the light is detected, and the light absorption coefficient of the exhaust gas (m^-1 ) is calculated. The amount of light absorbed by the particulate matter in the exhaust gas is called the light absorption coefficient (K), and the relationship with the attenuated light is widely known as the Bare-Lambert law.
K = − (1 / La) · {ln (I / I₀ )} (1 formula) where K: light absorption coefficient (1 / m)
La: Effective optical path length (m)
I: Light intensity when exhaust gas is present
I₀ : Light quantity when there is no exhaust gas
I / I₀ : Transmittance of exhaust gas The light emission amount of thelight emitting element 4 may be influenced by the ambient temperature. For example, when thelight emitting element 4 is configured by an LED (light emitting diode), it is widely known that the amount of light emitted from the LED greatly decreases as the ambient temperature of the LED increases and increases as the temperature decreases. It is necessary to compensate.

これまでの温度補償技術は、ＬＥＤ付近に感温素子を配置し、その温度測定値からＬＥＤに流す電流を調整して発光量を一定にする手法、あるいは、温度測定値から受光側で受光量を補償する手法を用いている。
スモークメータにおいて、光吸収係数の温度補償を行う技術としては特許文献１及び２に記載されたものがある。Conventional temperature compensation technology is a method of arranging a temperature sensing element near the LED and adjusting the current flowing to the LED from the measured temperature value to make the emitted light amount constant, or the received light amount on the light receiving side from the measured temperature value Is used.
As a technique for performing temperature compensation of a light absorption coefficient in a smoke meter, there are those described in Patent Documents 1 and 2.

このうち、特許文献１に記載された技術は排ガス中の粒子状物質を吸着させてろ紙からの反射光を測定する反射式スモークメータに関する技術であるのでオパシメータ（透過型スモークメータ）とは測定原理が異なっている。 Among these, the technique described in Patent Document 1 is a technique related to a reflective smoke meter that adsorbs particulate matter in exhaust gas and measures the reflected light from the filter paper. Therefore, the opacimeter (transmission type smoke meter) is a measurement principle. Is different.

また特許文献２に記載された技術では排気管から排圧分流された排ガスは、オパシメータの測定室に導入され左右に分流され、測定室の左右の終端で掃気エアー（清浄空気）と合流させて大気に放出する。その間に発光素子のＬＥＤから発せられた光は測定室内の排ガスを透過し、減衰して受光素子で受光され、減衰量から排ガスの光吸収係数が求められる。エアーカーテン１４、１５は掃気エアーを流して、受光素子、発光素子が排ガスの粒状物質、水分、等により汚染されるのを防ぐ役割を果たす。 Further, in the technique described in Patent Document 2, the exhaust gas divided by the exhaust pressure from the exhaust pipe is introduced into the measurement chamber of the opacimeter and divided into left and right, and merged with scavenging air (clean air) at the left and right ends of the measurement chamber. Release into the atmosphere. In the meantime, the light emitted from the LED of the light emitting element passes through the exhaust gas in the measurement chamber, attenuates and is received by the light receiving element, and the light absorption coefficient of the exhaust gas is obtained from the attenuation amount. Theair curtains 14 and 15 serve to prevent the light receiving element and the light emitting element from being contaminated by particulate matter, moisture, etc. of the exhaust gas by flowing scavenging air.

特開平０７−２６０６８３JP 07-260683 A特開平１１−１８３３７９JP-A-11-183379

このような、従来のオパシメータ１０１の問題点を次に示す。
（１）温度に対するＬＥＤの発光量の特性は、個々に特有な特性を示す。よって個別の温
度特性を得る必要がある。
（２）感温素子のメモリ付けを必要とする。
（３）感温素子の熱容量と、ＬＥＤの熱容量が異なり、周囲温度が変化した場合に感温素
子とＬＥＤの温度変化に違いができ、正しい補償値になるまで時間差が生じる。
（４）ＬＥＤの自己発熱により発光量変動を生じる。これは感温素子では検知できない。Such problems of theconventional opacimeter 101 are as follows.
(1) The characteristic of the light emission amount of the LED with respect to temperature shows a characteristic specific to each. Therefore, it is necessary to obtain individual temperature characteristics.
(2) A memory for the temperature sensitive element is required.
(3) The heat capacity of the temperature sensitive element and the heat capacity of the LED are different, and when the ambient temperature changes, the temperature change of the temperature sensitive element and the LED can be different, and a time difference occurs until the correct compensation value is obtained.
(4) The light emission amount fluctuates due to self-heating of the LED. This cannot be detected by the temperature sensitive element.

さらに感温素子によってＬＥＤの周囲の温度を測定し、その温度測定値からＬＥＤの発光量を補償したり、受光量を補正するためには、感温素子が必要となるだけでなく、ＬＥＤの発光量を求めるには間接的で、誤差が入り易い。 Furthermore, in order to measure the ambient temperature of the LED with the temperature sensing element and compensate the light emission amount of the LED from the temperature measurement value or to correct the light reception amount, not only the temperature sensing element is required, but also the LED It is indirect to determine the amount of light emission, and errors are likely to occur.

このようなことから、個々のＬＥＤに個別の温度特性を得る必要がなく、感温素子を使用することなく迅速にＬＥＤの発光量を補償することができ、温度変化に対応したＬＥＤの発光量を直接に求めることができるオパシメータにおける発光素子光度補償技術の開発が望まれている。 For this reason, it is not necessary to obtain individual temperature characteristics for each LED, and the light emission amount of the LED can be quickly compensated without using a temperature sensing element, and the light emission amount of the LED corresponding to the temperature change. It is desired to develop a light-emitting element light intensity compensation technique in an opacimeter that can directly determine the light intensity.

この目的に対応してこの発明のオパシメータにおける発光素子光度補償装置は、被測定対象の排ガスを導入する測定室を通して測定用受光素子に達する測定用光路を形成する発光素子からの光を前記測定室内の排出ガスに透過させて前記測定用受光素子で受光するように構成したオパシメータにおける発光素子光度補償装置であって、前記発光素子からの発光を前記測定室を介さないで受け得る位置に参照用受光素子を配置したことを特徴としている。 Corresponding to this object, the light-emitting element luminous intensity compensation device in the opacimeter according to the present invention transmits light from a light-emitting element that forms a measurement optical path that reaches a light-receiving element for measurement through a measurement chamber that introduces exhaust gas to be measured. Is a light-emitting element light intensity compensation device in an opacimeter configured to be transmitted through an exhaust gas and received by the light-receiving element for measurement, and used as a reference at a position where light emitted from the light-emitting element can be received without passing through the measurement chamber It is characterized in that a light receiving element is arranged.

この発明のオパシメータにおける発光素子光度補償装置では、
（１）感温素子が不要になり、装置の構成を簡単にすることができる。
（２）また感温素子が無くなることで、温度に関連する調整が不要になり、迅速な測定が可能になる。
（３）また、ＬＥＤの発光光度の個々の温度特性取得作業が不要になり、測定操作が簡易になる。
（４）さらに温度変化に大変優れ、かつ低コストのオパシメータが構築できる。In the light emitting element luminous intensity compensation device in the opacimeter of the present invention,
(1) A temperature sensitive element is not required, and the configuration of the apparatus can be simplified.
(2) Further, since there is no temperature sensing element, adjustment related to temperature becomes unnecessary, and rapid measurement becomes possible.
(3) Moreover, the individual temperature characteristic acquisition work of the luminous intensity of the LED becomes unnecessary, and the measurement operation is simplified.
(4) Furthermore, it is possible to construct an opacimeter that is extremely excellent in temperature change and low in cost.

以下この発明の詳細を実施の形態を示す図面について説明する。
図１及び図２において、１はオパシメータである。オパシメータ１は発光素子発光度補償装置（以下単に「補償装置」と称する）２を備えている。
補償装置２は測定室３と発光素子４と受光素子５とを備えている。
測定室３は排ガスを収容可能な空間をなし、その中間部に被測定対象である排ガスを導入する排ガス入り口６とその両端に排ガスを排出する排ガス出口７、８とが開口している。
排ガス出口７、８にはエアーカーテン部１４、１５が設けられ、エアーカーテン部１４、１５には掃気エアーが流出され、排ガス出口７、８における排ガスの流出を案内して排ガスが後述する発光素子４や受光素子５に接触するのを阻止する。The details of the present invention will be described below with reference to the drawings showing embodiments.
1 and 2, reference numeral 1 denotes an opacimeter. The opacimeter 1 includes a light emitting element luminous intensity compensation device (hereinafter simply referred to as “compensation device”) 2.
The compensation device 2 includes a measurement chamber 3, alight emitting element 4, and alight receiving element 5.
The measurement chamber 3 has a space in which exhaust gas can be accommodated, and an exhaust gas inlet 6 for introducing the exhaust gas to be measured is opened at an intermediate portion thereof, and exhaust gas outlets 7 and 8 for discharging the exhaust gas are opened at both ends thereof.
Air curtain portions 14 and 15 are provided at the exhaust gas outlets 7 and 8, scavenging air flows out to theair curtain portions 14 and 15, and the exhaust gas is described later by guiding the outflow of the exhaust gas at the exhaust gas outlets 7 and 8. 4 and thelight receiving element 5 are blocked.

一方の排ガス出口７に対向して発光素子４が配置されていて、発光素子４は測定室３を貫通して、排ガス出口７から排ガス出口８に達する光路１１に光を投射することが可能である。発光素子４としてはＬＥＤやランプで構成することができる。 The light-emittingelement 4 is arranged so as to face one of the exhaust gas outlets 7, and the light-emittingelement 4 can project light onto theoptical path 11 that passes through the measurement chamber 3 and reaches the exhaust gas outlet 8 from the exhaust gas outlet 7. is there. Thelight emitting element 4 can be constituted by an LED or a lamp.

排ガス出口８に対向して光路１１上に受光素子５が配置されている。受光素子５はフォトダイオード等で構成されている。 The light receivingelement 5 is disposed on theoptical path 11 so as to face the exhaust gas outlet 8. The light receivingelement 5 is composed of a photodiode or the like.

発光素子４の近傍に補償装置２が設けられている。補償装置２は参照用受光装置１２を備えている。
参照用受光素子１２の目的は、周囲温度の変化、およびＬＥＤ等の発光素子４の自己発熱によるＬＥＤ光量変化を検出することである。
発光素子４の光路１１に向う光と参照用受光素子１２に向う光との光量比が定まっているもので、かつ参照用受光素子１２は受光素子５と温度特性が同じもので構成し、また参照用受光素子１２と受光素子５の設置位置は同じ温度環境で設置する。A compensation device 2 is provided in the vicinity of thelight emitting element 4. The compensation device 2 includes a referencelight receiving device 12.
The purpose of the referencelight receiving element 12 is to detect a change in the amount of LED light due to a change in ambient temperature and self-heating of thelight emitting element 4 such as an LED.
The light quantity ratio between the light directed to theoptical path 11 of thelight emitting element 4 and the light directed to the referencelight receiving element 12 is fixed, and the referencelight receiving element 12 has the same temperature characteristics as thelight receiving element 5, and The referencelight receiving element 12 and thelight receiving element 5 are installed in the same temperature environment.

また参照用受光素子１２の設置位置は発光素子４からの光が受けられる位置で、かつ発光素子４からの受光量に影響を与えるような実質的な熱量の伝達がない位置であることが必要である。 Thelight receiving element 12 for reference needs to be installed at a position where light from thelight emitting element 4 can be received and a position where there is no substantial amount of heat that affects the amount of light received from thelight emitting element 4. It is.

さらに参照用受光素子１２の設置位置は発光素子４の光路１１と干渉しない位置である必要がある。
このような発光素子４、受光素子５、参照用受光素子１２の条件を満たすために、受光素子５と参照用受光素子１２は一例として
発光素子４はＬＥＤで構成し、受光素子５、参照用受光素子１２は共にフォトダイオードで構成し、かつ参照用受光素子１２の設置位置は、受光面１３が光路１１と平行で発光素子４の側面１６からＸｍｍ（Ｘｍｍ＝０．２〜０．５ｍｍ）離れた位置にする。
受光素子５と参照用受光素子１２との２つの受光素子は温度依存性が少ないもの、あるいは温度に対する受光素子が同じ特性のものを採用する。Furthermore, the referencelight receiving element 12 needs to be installed at a position that does not interfere with theoptical path 11 of thelight emitting element 4.
In order to satisfy the conditions of thelight emitting element 4, thelight receiving element 5, and the referencelight receiving element 12, thelight receiving element 5 and the referencelight receiving element 12 are constituted by LEDs as an example, and thelight receiving element 5 and the referencelight receiving element 12 are used for reference. Both of thelight receiving elements 12 are constituted by photodiodes, and the referencelight receiving element 12 is installed at a position of X mm (X mm = 0.2 to 0.5 mm) from theside surface 16 of thelight emitting element 4 with thelight receiving surface 13 parallel to theoptical path 11. Set it apart.
As the two light receiving elements, thelight receiving element 5 and the referencelight receiving element 12, one having a small temperature dependency or one having the same characteristics with respect to the temperature is employed.

参照用受光素子１２は、ＬＥＤの自己加熱の影響を受けず、かつ、受光量が不足しない距離で図２のようにＬＥＤの側面近傍に配置する。 The referencelight receiving element 12 is arranged in the vicinity of the side surface of the LED as shown in FIG.

参照用受光素子１２の測定値は、ＬＥＤの自己加熱と周囲温度の影響で変化した光量が検出でき、排ガスに含まれる粒状物質による減衰には影響されない。 The measured value of the referencelight receiving element 12 can detect the amount of light changed by the self-heating of the LED and the ambient temperature, and is not affected by the attenuation caused by the particulate matter contained in the exhaust gas.

このように構成されたオパシメータ１における発光度補償つき排ガスの粒状物質の濃度測定は次のようにして行う。
被測定対象である排ガスはエンジンの排気管から排圧によって排ガス入口６から測定室３に入り左右に分かれて測定室３内に充満し、濃度計測され、その後、測定室３の両端の排ガス出口７、８からエアーカーテン１４、１５の掃気空気流に案内されて外部に排出されている。In the thus configured opacimeter 1, the concentration measurement of the particulate matter in the exhaust gas with luminosity compensation is performed as follows.
Exhaust gas to be measured enters the measurement chamber 3 through the exhaust gas inlet 6 by exhaust pressure from the exhaust pipe of the engine, is divided into left and right, fills the measurement chamber 3, measures the concentration, and then exhaust gas outlets at both ends of the measurement chamber 3. 7 and 8 are guided by the scavenging air flow of theair curtains 14 and 15 and discharged to the outside.

光吸収係数の計測においては、発光素子４が発光した発光の主要部分はコンデンサーレンズ１７を通して、光路１１に従って測定室３を通り、その間に測定室３内の排ガスの粒状物質によって減衰されて受光素子５に達し、受光量の計測がなされる。 In the measurement of the light absorption coefficient, the main part of the light emitted by thelight emitting element 4 passes through thecondenser lens 17 and the measuring chamber 3 according to theoptical path 11, while being attenuated by the particulate matter of the exhaust gas in the measuring chamber 3 to receive the light receiving element. 5 is reached, and the amount of received light is measured.

一方、発光素子４の発光の一定割合は排ガスに減衰されない状態で参照用受光素子１２に達する。 On the other hand, a certain proportion of the light emitted from thelight emitting element 4 reaches the referencelight receiving element 12 without being attenuated by the exhaust gas.

発光素子４の周囲温度が変動した場合、発光素子４の光量変動は受光素子１２と同じ割合で変動する。 When the ambient temperature of thelight emitting element 4 varies, the light amount variation of thelight emitting element 4 varies at the same rate as thelight receiving element 12.

一般に透過率（Ｔ）はＴ＝（Ｉ_Ｓ／Ｉ_Ｓ０）×１００（２式）と表される。
Ｔ：粒状物質の透過率（％）
Ｉ_Ｓ：粒状物質が存在するときの受光素子５の受光量
Ｉ_Ｓ０：粒状物質が存在しないときの受光素子５の受光量
受光素子Ｒを利用して温度補償をした透過率は、
Ｔ＝（Ｉ_Ｓ／Ｉ_Ｓ０）・（Ｉ_Ｒ０／Ｉ_Ｒ）×１００（３式）となる。
Ｔ：粒状物質の透過率（％）
Ｉ_Ｓ：粒状物質が存在するときの受光素子５の受光量
Ｉ_Ｓ０：粒状物質が存在しないときの受光素子５の受光量
Ｉ_Ｒ：粒状物質が存在するときの受光素子１２の受光量
Ｉ_Ｒ０ : 粒状物質が存在しないときの受光素子１２の受光量
周囲温度の影響によりＬＥＤ発光量が変動した場合のそれぞれの受光量は同じ割合で影響を受ける。温度による変動分をａとすると、Ｉ_ＳとＩ_Ｒはそれぞれ
Ｉ_Ｓ→ａ・Ｉ_Ｓ
Ｉ_Ｒ→ａ・Ｉ_Ｒ
となる。Generally, the transmittance (T) is expressed as T = (I_S / I_S0 ) × 100 (2 formulas).
T: Permeability of particulate matter (%)
I_S: amount of light received by thelight receiving element 5 when the particulate material is present I_S0: transmittance obtained by temperature compensation using the received light amount receiving element R of the light-receivingelement 5 when the particulate material is not present,
T = (I_S / I_S0 ) · (I_R0 / I_R ) × 100 (3 formulas).
T: Permeability of particulate matter (%)
I_S : Amount of light received by thelight receiving element 5 when the particulate matter is present I_S0 : Amount of light received by thelight receiving element 5 when no particulate matter is present I_R : Amount of received light I_R0 of thelight receiving element 12 when the particulate matter is present : Amount of light received by thelight receiving element 12 when no particulate matter is present The amount of received light when the amount of light emitted by the LED varies due to the influence of the ambient temperature is affected at the same rate. If the fluctuation due to temperature is a, I_S and I_R are I_S → a · I_S respectively.
I_R → a ・ I_R
It becomes.

これを３式に代入すると
Ｔ＝｛（ａ・Ｉ_Ｓ）／Ｉ_Ｓ０｝・｛Ｉ_Ｒ０／（ａ・Ｉ_Ｒ）｝×１００（４式）
となり、温度変動による光量変動分は相殺される。
こうして図３に示すように、周囲温度の変動に対して透過率の測定値が良好に補償される。
以上の説明から明らかなように、本発明による補償検出器付オパシメータ１によって、測定中の温度変化および光源の光量変化の影響は完全に補償できる。図３には従来の測定方式の検出器の場合の周囲温度の影響の測定例に対比して、本発明の補償検出器付の場合の周囲温度の影響の実測例が示してある。このように、５℃〜４５℃と大きく周囲温度が変化しても測定値には全く影響しない。また、一般には光源は時間と共に光量が変化するが、本発明の補償検出器によってはこの光源光量の変化も十分に補償して測定できる。さらに、測定出力信号は通常のアナログ計測器においては３桁程度の分解能しか得られないが、本発明による演算処理によって４桁以上の精度と読み取りが可能となる。これらの効果によって、ディーゼル排気の黒煙濃度の測定において従来の方式よりも１桁低い濃度まで高精度と高分解能で測定できる。Substituting this into Equation 3, T = {(a · I_S ) / I_S0 } · {I_R0 / (a · I_R )} × 100 (Equation 4)
Thus, the light quantity fluctuation due to temperature fluctuation is canceled out.
Thus, as shown in FIG. 3, the measured transmittance value is well compensated for variations in ambient temperature.
As is clear from the above description, the effect of the temperature change during measurement and the light quantity change of the light source can be completely compensated by the opacimeter 1 with a compensation detector according to the present invention. FIG. 3 shows an actual measurement example of the influence of the ambient temperature in the case with the compensation detector of the present invention, in contrast to the measurement example of the influence of the ambient temperature in the case of the detector of the conventional measurement method. In this way, even if the ambient temperature changes greatly as 5 ° C. to 45 ° C., the measured value is not affected at all. In general, the light amount of the light source changes with time. However, depending on the compensation detector of the present invention, the change in the light source amount can be sufficiently compensated for and measured. Furthermore, the measurement output signal can only have a resolution of about 3 digits in a normal analog measuring instrument, but the arithmetic processing according to the present invention makes it possible to read and read with an accuracy of 4 digits or more. Due to these effects, the black smoke concentration of diesel exhaust can be measured with high accuracy and high resolution down to an order of magnitude lower than the conventional method.

この発明のオパシメータの構成を示す説明図Explanatory drawing which shows the structure of the opacimeter of this inventionこの発明の発光素子光度補償装置Light-emitting element luminous intensity compensation device of the present invention透過率と周囲温度との関係を示すグラフGraph showing the relationship between transmittance and ambient temperature従来のオパシメータの構成を示す説明図Explanatory drawing showing the configuration of a conventional opacimeter

１オパシメータ
２発光素子発光度補償装置
３測定室
４発光素子
５受光素子
６排ガス入口
７排ガス出口
８排ガス出口
１１光路
１２参照用受光素子
１４エアーカーテン部
１５エアーカーテン部
１６発光素子の側面
１７コンデンサーレンズ
２１排ガス
１０１オパシメータDESCRIPTION OF SYMBOLS 1 Opacimeter 2 Light emitting element luminous intensity compensation apparatus 3Measurement chamber 4Light emitting element 5 Light receiving element 6 Exhaust gas inlet 7 Exhaust gas outlet 8Exhaust gas outlet 11Optical path 12 Light receiving element forreference 14Air curtain part 15Air curtain part 16 Side surface of light emittingelement 17Condenser lens 21exhaust gas 101 opacimeter

Claims

Translated fromJapanese

被測定対象の排ガスを導入する測定室を通して測定用受光素子に達する測定用光路を形成する発光素子からの光を前記測定室内の排出ガスに透過させて前記測定用受光素子で受光するように構成したオパシメータにおける発光素子光度補償装置であって、前記発光素子からの発光を前記測定室を介さないで受け得る位置に参照用受光素子を配置したことを特徴とするオパシメータにおける発光素子光度補償装置。 A configuration in which light from a light-emitting element that forms a measurement optical path that reaches a measurement light-receiving element through a measurement chamber that introduces exhaust gas to be measured is transmitted through the exhaust gas in the measurement chamber and received by the measurement light-receiving element. A light-emitting element luminous intensity compensation device in an opacimeter, wherein a reference light-receiving element is arranged at a position where light from the light-emitting element can be received without passing through the measurement chamber.

前記発光素子がＬＥＤであることを特徴とする請求項１記載のオパシメータにおける発光素子光度補償装置。 2. The light-emitting element luminous intensity compensation device in an opacimeter according to claim 1, wherein the light-emitting element is an LED.

前記参照用受光素子は前記測定用受光素子と温度特性が同じであることを特徴とする請求項１記載のオパシメータにおける発光素子光度補償装置。 The light-emitting element light intensity compensation device in an opacimeter according to claim 1, wherein the reference light-receiving element has the same temperature characteristic as the measurement light-receiving element.

前記参照用受光素子の設置位置は前記発光素子の設置位置と同じ環境温度であることを特徴とする請求項１記載のオパシメータにおける発光素子光度補償装置。 The light emitting element light intensity compensation device in an opacimeter according to claim 1, wherein the installation position of the reference light receiving element is the same environmental temperature as the installation position of the light emitting element.

前記参照用受光素子の設置位置は前記発光素子からの前記参照用受光素子の受光量に影響を与える熱量の熱伝達が無い位置で前記発光素子からの光が受けられる位置であることを特徴とする請求項１記載のオパシメータにおける発光素子光度補償装置。 The installation position of the reference light receiving element is a position where light from the light emitting element is received at a position where there is no heat transfer of the amount of heat that affects the amount of light received by the reference light receiving element from the light emitting element. The light-emitting element luminous intensity compensation device for an opacimeter according to claim 1.

前記参照用受光素子の設置位置は前記光路と干渉しない位置であることを特徴とする請求項１記載のオパシメータにおける発光素子光度補償装置。 The light-emitting element luminous intensity compensation device for an opacimeter according to claim 1, wherein the reference light-receiving element is installed at a position that does not interfere with the optical path.

前記発光素子は前記光路に向かう光と前記参照用受光素子に向かう光との光量比が定まっていることを特徴とする請求項１記載のオパシメータにおける発光素子光度補償装置。 The light-emitting element light intensity compensation device for an opacimeter according to claim 1, wherein the light-emitting element has a light amount ratio between light traveling toward the optical path and light traveling toward the reference light-receiving element.

前記参照用受光素子の前記光軸に平行な受光面は前記ＬＥＤから前記光軸から垂直な方向に０．２〜０．５ｍｍ離れて配置することを特徴とする請求項２記載のオパシメータにおける発光素子光度補償装置 3. The light emission in the opacimeter according to claim 2, wherein a light receiving surface parallel to the optical axis of the reference light receiving element is disposed 0.2 to 0.5 mm away from the LED in a direction perpendicular to the optical axis. Element brightness compensation device