JP4424906B2

JP4424906B2 - Dust measuring device

Info

Publication number: JP4424906B2
Application number: JP2002370679A
Authority: JP
Inventors: 佳幸下田; 正記渡辺
Original assignee: Osaka Gas Co Ltd
Current assignee: Osaka Gas Co Ltd
Priority date: 2002-01-25
Filing date: 2002-12-20
Publication date: 2010-03-03
Anticipated expiration: 2022-12-20
Also published as: JP2003287490A

Description

【０００１】
【発明の属する技術分野】
本発明は、流体に含まれたダストの濃度を測定するためのダスト測定装置に関する。
【０００２】
【従来の技術】
従来から、流体中に含まれたダストの濃度を測定するダスト測定装置として、光の散乱を利用した光散乱方式のものが知られている。この種のダスト測定装置は、測定領域に向けて測定光を照射するための照射手段と、測定領域からの被検知光を受光するための受光手段と、受光された被検知光を所要の通りに演算処理してダスト濃度を算出するためのダスト濃度演算手段と、を備え、流体流路に挿入される検知部ハウジングに照射手段及び受光手段の大部分が内蔵される。このようなダスト測定装置では、照射手段は検知部ハウジングの照射開口を通して測定領域に向けて測定光を照射し、受光手段は検知部ハウジングの受光開口を通して測定領域からの被検知光を受光する。このとき、測定領域を流れる流体中のダスト、即ち粉塵等が多い（又は少ない）と、照射された測定光がダストにより多く（又は少なく）散乱され、散乱した被検知光が明るく（又は暗く）なり、このようなことから、散乱光の散乱率に基づいて流体中のダスト濃度を測定することができる。
【０００３】
【発明が解決しようとする課題】
このようなダスト測定装置には、次の通りの問題がある。第１に、検知部ハウジング内に照射手段及び受光手段の大部分が内蔵されるが、このような構成に関連して検知部ハウジングが大きくなり、小径の流体流路を流れる流体中のダスト濃度を測定することが難しいという問題がある。第２に、流体流路中を流れるダストの濃度を測定するために用いるため、流体中のダストにより照射手段及び受光手段に関連する部材に傷等が生じ易く、それ故に、照射手段及び受光手段に関連する部材のメンテナンスを容易に行うことができるダスト測定装置の実現が望まれている。
【０００４】
また、このようなダスト測定装置においては、流体流路に検知部ハウジングを挿入するとき、また流体流路から検知部ハウジングを抜き取るときに、流体流路を流れる流体の一部が外部に流出するおそれがある。特に、流体流路を流れる流体が高圧の流体である場合、流体の漏れが発生し易くなる。
【０００５】
また、このようなダスト測定装置においては、ダスト濃度を検知する場合、ダスト測定装置全体を検知場所まで運んで測定しなければならず、その検知作業が煩雑である。
【０００６】
更に、このようなダスト測定装置においては、測定が正確に行われるように定期的に校正作業を行っている。このような校正作業では標準部材を測定領域に正確に位置付ける必要があり、正確な位置付けができないと、校正後の測定に誤差が生じる。
【０００７】
本発明の第１の目的は、照射手段及び受光手段に関連する構成を小型化し、これによって検知部ハウジングの小型化を図り、検知ハウジングの挿入を容易にするとともに、小径の流体流路を流れる流体中のダスト濃度をも計測することができるダスト測定装置を提供することである。
【０００８】
本発明の第２の目的は、検知部ハウジングの取付け、取外し時における流体の漏れを確実に防止することができるダスト測定装置を提供することである。
本発明の第３の目的は、比較的簡単な作業でもってダストの濃度を測定することができるダスト測定装置を提供することである。
【００１０】
本発明は、照射開口及び受光開口を有する検知部ハウジングと、前記照射開口を通して測定領域に向けて測定光を照射するための照射手段と、前記測定領域からの被検知光を前記受光開口を通して受光するための受光手段と、前記受光手段にて受光された被検知光を所要の通りに演算処理してダスト濃度を算出するダスト濃度演算手段と、を具備するダスト測定装置であって、
前記検知部ハウジングの所定部位に凹部が設けられ、前記凹部の片側に前記照射開口が設けられ、その他側に前記受光開口が設けられ、前記照射開口及び前記受光開口は前記検知部ハウジングの軸線方向に対向しており、
前記照射手段は、測定光を発光するための発光源と、前記発光源からの測定光を前記照射開口に導くための第１光ファイバとを備え、前記受光手段は、被検知光を受光するための受光素子と、前記受光開口を通して導入された被検知光を前記受光素子に導くための第２光ファイバとを備えており、
前記発光源からの測定光は、前記第１光ファイバを通して前記照射開口から前記検知部ハウジングの軸線方向に対して１０〜３０度傾斜して前記測定領域に向けて照射され、前記測定領域からの被検知光は、前記検知部ハウジングの軸線方向に対して１０〜３０度傾斜して前記受光開口を通して導入され、
照射手段と前記受光手段の一方は、光を反射するための反射鏡を含んでおり、
更に、前記検知部ハウジングは、流体流路を規定する流体配管に連通するシール管の挿入路を通して前記流体流路の前記測定領域に挿入され、前記シール管の前記挿入路の一端部には、一対の基部側シール部材が設けられ、前記挿入路の他端部には、一対の先端側シール部材が設けられ、前記挿入路を通して流体流路の前記測定領域に挿入するとき、前記シール管の内周面と前記検知部ハウジングの外周面との間は、前記一対の基部側シール部材及び前記一対の先端側シール部材のうちの少なくとも二つのシール部材によってシールされることを特徴とする。
【００１１】
本発明に従えば、測定光を照射するための照射手段は、発光源及び第１光ファイバを備え、また被検知光を受光するための受光手段は受光素子及び第２光ファイバを備えているので、発光源からの測定光は第１光ファイバ及び照射開口を通して測定領域に向けて照射され、また被検知光は受光開口及び第２光ファイバを通して受光素子に受光される。そして、測定光の伝送は第１光ファイバにより行われ、また被検知光の伝送は第２光ファイバにより行われるので、検知部ハウジングの外形を小さく細くすることができる。また、検知部ハウジングの凹部の片側に照射開口が設けられ、その他側に受光開口が設けられ、照射開口及び受光開口は検知部ハウジングの軸線方向に対向しているので、これによっても、検知部ハウジングの外形を効果的に小さくすることができる。また、照射手段及び受光手段の一方が反射鏡を含んでいるので、照射開口及び受光開口を検知部ハウジングの軸線方向に対向させたとしても、測定光又は被検知光を伝送する際に第１光ファイバ又は第２光ファイバを曲げることなく、測定光又は被検知光を反対方向に反射させて伝送することができ、これによって、検知部ハウジングの外形を更に小さく細くすることができ、これにより、検知部ハウジングの流体流路への挿入を容易にし、小径の孔を通して流体流路に挿入することが可能になるとともに、小径の流体流路を流れる流体中のダスト濃度を測定することが可能となる。更に、発光源からの測定光は、照射開口から検知部ハウジングの軸線方向に対して１０〜３０度傾斜して測定領域に向けて照射され、また測定領域からの被検知光は、検知部ハウジングの軸線方向に対して１０〜３０度傾斜して前記反射鏡に導かれるので、検知部ハウジングの外形を小さくすることができるとともに、照射開口からの照射光が直接的に受光開口を通して受光されることを防止することができる。加えて、検知部ハウジングが挿入されるシール管の挿入路の一端部には一対の基部側シール部材が設けられ、その他端部側には一対の先端側シール部材が設けられており、このように合計４つのシール部材が所定の位置関係で設けられているので、凹部を有する検知部ハウジングを挿入路を通して流体流路に挿入しても、少なくとも２つのシール部材がシール管の内周面と検知部ハウジングの外周面との間をシールし、かくして、流体流路を流れる流体の挿入路を通しての漏れを確実に防止することができる。尚、反射鏡は光を反対方向に伝送するために用いられ、測定光を反対方向に伝送する場合には照射手段に含まれ、被検知光を反対方向に反射する場合には受光手段に含まれる。
また、本発明は、照射開口及び受光開口を有する検知部ハウジングと、前記照射開口を通して測定領域に向けて測定光を照射するための照射手段と、前記測定領域からの被検知光を前記受光開口を通して受光するための受光手段と、前記受光手段にて受光された被検知光を所要の通りに演算処理してダスト濃度を算出するダスト濃度演算手段と、を具備するダスト測定装置であって、
前記検知部ハウジングの所定部位に凹部が設けられ、前記凹部の片側に前記照射開口が設けられ、その他側に前記受光開口が設けられ、前記照射開口及び前記受光開口は前記検知部ハウジングの軸線方向に対向しており、
前記照射手段は、測定光を発光するための発光源と、前記発光源からの測定光を前記照射開口に導くための第１光ファイバとを備え、前記受光手段は、被検知光を受光するための受光素子と、前記受光開口を通して導入された被検知光を前記受光素子に導くための第２光ファイバとを備えており、
前記発光源からの測定光は、前記第１光ファイバを通して前記照射開口から前記検知部ハウジングの軸線方向に対して１０〜３０度傾斜して前記測定領域に向けて照射され、前記測定領域からの被検知光は、前記検知部ハウジングの軸線方向に対して１０〜３０度傾斜して前記受光開口を通して導入され、
照射手段と前記受光手段の一方は、光を反射するための反射鏡を含んでおり、
更に、前記検知部ハウジングには、測定値を構成するための校正ユニットが着脱自在に取り付けられ、前記校正ユニットは、前記検知部ハウジングに着脱自在に取り付けられるユニットハウジングと、測定値の校正に用いる標準検知部を有し、前記ユニットハウジングの取付部に装着される標準部材と、前記検知部ハウジングに対して前記ユニットハウジングを所定の位置関係に位置付け固定するための芯出し固定機構と、を備えており、
前記検知部ハウジングに前記ユニットハウジングを装着して前記芯出し固定機構により芯出し固定すると、前記ユニットハウジングは前記検知部ハウジングに対して同心状に位置決め固定され、この状態にて前記標準部材を前記ユニットハウジングに装着すると、前記標準部材の前記標準検知部が前記測定領域に位置付けられることを特徴とする。
本発明に従えば、照射手段、受光手段及び検知ハウジングに関する構成が上述したダスト測定装置と実質上同一であるので、同様の作用効果が達成される。加えて、ユニットハウジングを検知部ハウジングに装着するための芯出し固定機構は、検知部ハウジングに対してユニットハウジングを同心状に位置決め固定し、このように固定した状態において、標準部材をユニットハウジングに装着すると、標準部材の標準検知部が測定領域に位置付けられ、従って、照射手段は標準部材の標準検知部に向けて測定光を照射し、またこの標準検知部からの被検知光が受光手段に受光され、かくして、標準部材を用いて測定値の構成を正確に行うことができる。
【００１２】
本発明では、前記受光手段が前記反射鏡を含み、前記反射鏡が前記受光開口と前記第２光ファイバとの間に配設されており、前記検知部ハウジングの前記受光開口を通して導入された被検知光は、前記反射鏡に反射された後に前記第２光ファイバを通して前記受光素子に受光されることを特徴とする。
本発明に従えば、受光手段が反射鏡を含んでいるので、受光開口を通して導入された被検知光は、反射鏡により反対側に反射され、第２光ファイバを通して受光素子に導かれ、受光素子に関連して検知部ハウジングを小型化することができる。
【００１４】
また、本発明では、前記検知部ハウジングは相互に着脱自在に装着される第１及び第２ハウジング部材から構成され、前記照射開口は前記第１ハウジング部材に設けられ、前記受光開口は前記第２ハウジング部材に設けられており、前記照射開口に照射口カバーが着脱自在に装着され、前記受光開口に受光カバーが着脱自在に装着されており、更に、前記反射鏡は前記第２ハウジング部材内に着脱自在に装着されていることを特徴とする。
【００１５】
本発明に従えば、検知部ハウジングの照射開口に照射口カバーが着脱自在に装着され、またこの検知部ハウジングの受光開口に受光口カバーが着脱自在に装着されるので、検知部ハウジングから照射口カバー及び受光口カバーを取り外すことができ、これらのメンテナンス、交換を容易に行うことができる。また、検知部ハウジングは相互に着脱自在に装着される第１及び第２ハウジング部材から構成され、この第２ハウジング部材に反射鏡が着脱自在に装着されているので、第１ハウジング材から第２ハウジング部材を外すことによって、反射鏡を第２ハウジング部材から取り外すことができ、反射鏡のメンテナンス、交換をも容易に行うことができる。
【００３２】
【発明の実施の形態】
以下、添付図面を参照して、本発明に従うダスト測定装置の一実施形態について説明する。図１は、本発明に従うダスト測定装置の全体を示す概略図であり、図２は、図１のダスト測定装置の一部を示す部分断面図であり、図３は、図１のダスト測定装置の照射部及び受光部付近を示す部分断面図であり、図４は、図１のダスト測定装置の受光部を拡大して示す部分拡大断面図であり、図５は、図１のダスト測定装置の照射部及び受光部付近を一部分解して示す分解断面図であり、図６は、図１のダスト測定装置の検知部ハウジングを流体流路に挿入するときの状態を示す断面図であり、図７は、図６の状態から検知部ハウジングを少し挿入した状態を示す部分断面図であり、図８は、図７に示す状態から検知部ハウジングを少し挿入した状態を示す部分断面図であり、図９は、図８に示す状態から検知部ハウジングを少し挿入した状態を示す部分断面図であり、図１０は、図９に示す状態から検知部ハウジングを更に少し挿入した状態を示す部分断面図であり、図１１は、変形形態の検知部ハウジングにユニットハウジングを装着した状態を示す部分断面図であり、図１２は、検知部ハウジングにユニットハウジングを取り付けた状態を示す右側面図であり、図１３は、図１２におけるＸＩＩＩ−ＸＩＩＩ線による断面図である。
【００３３】
図１において、図示のダスト測定装置は、流体配管２により規定された流体流路４を流れる流体に含まれた粉塵等のダスト６の濃度を測定するために用いられる。このダスト測定装置は、円筒状の検知部ハウジング８を備え、この検知部ハウジング８の先端側が、挿入管構造７を通して流体流路４内に挿入される。この形態では、挿入管構造７は、流体配管２の所定部位に分岐して設けられたボールバルブ部１０及びガスシール部１２から構成され、これらボールバルブ部１０及びガスシール部１２を通して流体流路４内に挿入される。流体流路４には、流体としての燃料用ガス、例えば高圧（例えば４ＭＰａ）の都市ガスが矢印で示す方向に流れており、ダスト測定装置は、このように流れる燃料用ガス中のダスト濃度を測定するのに好都合に用いることができるが、一般的なガスに含まれたダストの濃度を測定するのにも広く用いることができる。尚、ボールバルブ部１０及びガスシール部１２については、後述する。
【００３４】
図２及び図３をも参照して、検知部ハウジング８は基部側の第１ハウジング部材１１と先端側の第２ハウジング部材１３とから構成され、第１及び第２ハウジング部材１１，１３が相互に着脱自在に螺着される。この検知部ハウジング８の先端側、即ち第２ハウジング部材１３の所定部位には開口が形成され、この開口により凹部１５が形成され、この凹部１５の片側（この形態では基部側）に照射部１４が設けられ、その他側（この形態では先端側）に受光部１６が設けられている。検知部ハウジング８の照射部１４には照射開口１８が設けられ、この照射開口１８に照射口カバー２０が後述する如くして着脱自在に装着されている。また、検知部ハウジング８の受光部１６には受光開口２２が設けられ、この受光開口２２に後述する如くして着脱自在に受光口カバー２４が装着されている。照射口カバー２０及び受光口カバー２４はガラス等の透明な材料から構成され、照射口カバー２０及び受光口カバー２４によって、照射開口１８及び受光開口２２が密封される。
【００３５】
ダスト測定装置は、検知部ハウジング８と分離した測定装置本体２６を備えている。測定装置本体２６には、測定光を発光するための発光源２８と、後述する被検知光を受光するための受光素子３０と、受光素子３０により受光された被検知光を所要の通りに演算処理するためのダスト濃度演算手段３２が内蔵されている。発光源２８は、例えばレーザ発振素子から構成され、近赤外線レーザ光を発光する。尚、指向性の強い他の光を発光する発光源を用いるようにしてもよい。また、受光素子３０は、例えばＣＣＤから構成され、被検知光を受光する。ダスト濃度演算手段３２は、例えばマイクロコンピュータから構成され、受光素子３０からの受光信号を演算処理して流体中に含まれたダストの濃度を算出する。流体中に含まれているダスト量と被検知光とは所定の関係があり、ダスト量が多い（又は少ない）と、ダストによる光の散乱が大きく（又は小さく）なり、従って、受光素子３０に受光される受光量が大きく（又は小さく）なり、このような関係を利用してダスト濃度演算手段３２はダスト濃度を算出する。この測定装置本体２６には、印刷装置３４及び表示装置３６が付設されており、印刷装置３４は、ダスト濃度演算手段３２により算出したダスト濃度を印刷し、また表示装置３６は、算出したダスト濃度を表示する。
【００３６】
この測定装置本体２６と検知部ハウジング８とは、第１及び第２光ファイバ３８，４０により接続されている。第１光ファイバ３８は、発光源２８からの測定光を照射部１４に導き、第２光ファイバ４０は、受光部１６からの被検知光を受光素子３０に導く。このように構成されているので、発光源２８及び第１光ファイバ３８は、測定光を照射するための照射手段を構成し、第２光ファイバ４０及び受光素子３０は被検知光を受光するための受光手段を構成する。
【００３７】
主として図３を参照して、検知部ハウジング８の凹部１５の片側（この形態では第１ハウジング部材１１内に）には、この検知部ハウジング８内に第１閉塞部材４２が装着され、この第１閉塞部材４２にファイバ保持部材４４が螺着され、このファイバ保持部材４４内に第１光ファイバ３８の先端部が位置付け保持されている。このファイバ保持部材４４の先端部には照射開口１８を規定する第１凹部が設けられ、かかる第１凹部に照射口カバー２０が取り付けられている。この照射口カバー２０の表面側には第１カバー取付部材４６が配設され、この第１カバー取付部材４６を通して取付ねじ（図示せず）を第１閉塞部材４２に螺着することによって、照射口カバー２０が照射開口１８に押圧保持され、このようにして照射口カバー２０が照射部１４の第１凹部に着脱自在に装着される。この第１カバー取付部材４６の中央部には開口４８が設けられている。かく構成されているので、発光源２８からの測定光は、第１光ファイバ３８を通ってその先端面から投射され、ファイバ保持部材４４内の空間、照射口カバー２０及び第１カバー取付部材４６の開口４８を通して流体流路４内の測定領域５０に向けて照射される。
【００３８】
また、検知部ハウジング８の凹部１５の他側（この形態では第２ハウジング部材１３内に）には、この検知部ハウジング８内に受光部ホルダ５１を介して第２閉塞部材５２が装着され、この第２閉塞部材５２に集光レンズ５４及び反射鏡５６が装着されているとともに、第２光ファイバ４０の先端部が支持されている。第２閉塞部材５２の所定部位にはレンズ支持スリーブ５８が螺着され、このレンズ支持スリーブ５８の一端部を覆うようにカバー保持部材６０が螺着され、レンズ支持スリーブ５８の一端とカバー保持部材６０の中間段部との間にＯリング６２を介して集光レンズ５４が装着されている。このカバー保持部材６０の先端部には受光開口２２を規定する第２凹部が設けられ、かかる第２凹部に受光口カバー２４が取り付けられている。この受光口カバー２４の表面側には、照射口カバー２０側と同様に、第２カバー取付部材６４が配設され、この第２カバー取付部材６４を通して取付ねじ（図示せず）を第２閉塞部材５２螺着することによって、受光口カバー２４が受光開口２４に押圧保持され、このようにして受光口カバー２４が受光部１６の第２凹部に着脱自在に装着される。この第２カバー取付部材６４の中央部には開口６６が設けられている。
【００３９】
更に、第２閉塞部材５２の所定部位には切欠き６７が設けられ、この切欠き６７内に反射面が突出するように反射鏡５６が第２閉塞部材５２に取り付けられている。この形態では、反射鏡５６が鏡支持部材６８に取り付けられ、第２閉塞部材５２に設けられた挿入孔を通して反射鏡５６の先端側を挿入し、この鏡支持部材６８を固定用ねじ７０により第２閉塞部材５２の裏面に取り付けることにより、反射鏡５６が着脱自在に取り付けられる。また、第２閉塞部材５２にはファイバ挿入孔７２が設けられ、第２光ファイバ４０の先端部はこのファイバ挿入孔７２に挿入保持され、保持ホルダ７４を介して保持される。この第２閉塞部材５２は受光部ホルダ５１に装着され、受光部ホルダ５１は取付用ねじ７１によって第２ハウジング部材１３に着脱自在に取り付けられる。尚、受光部ホルダ５１と第２閉塞部材５２との間にはスペーサ７３が介在されている。第１閉塞部材４２と第２閉塞部材５２との間にはカバースリーブ７６が取り付けられ、このカバースリーブ７６内を通して第２光ファイバ４０が第２閉塞部材５２に延びている。
【００４０】
かく構成されているので、測定領域５０からの被検知光は、第２カバー取付部材６４の開口６６、受光口カバー２４、カバー保持部材６０の内部空間、集光レンズ５４、レンズ支持スリーブ５８の内部空間、第２閉塞部材５２の孔７７及び切欠き６７を通して反射鏡５６に至り、この反射鏡５６の反射面で反射された後、切欠き６７を通して第２光ファイバ４０の先端面に受光され、かく受光された被検知光は、第２光ファイバ４０を通して受光素子３０に導かれる。このように被検知光が受光されるので、集光レンズ５４及び反射鏡５６も上記受光手段の一部を構成する。
【００４１】
この実施形態では、図２及び図３から明らかなように、照射開口１８及び受光開口２２は検知部ハウジング７８の軸線方向に対向し、第１光ファイバ３８の先端部は、検知部ハウジング８の軸線方向（図２及び図３において左右方向）に対して１０〜３０度の適当な角度、例えば約２０度傾斜して保持され、従って、第１光ファイバ３８からの測定光は、上記軸線方向に対して例えば約２０度傾斜した角度で照射される。また、集光レンズ５４を通る光軸は、検知部ハウジング８の軸線方向に対して１０〜３０度の適当な角度、例えば約２０度傾斜し、また第２光ファイバ４０の先端部は検知部ハウジング８の上記軸線方向に延びており、従って、測定領域５０から上記光軸方向に散乱された被検知光は、反射鏡５６の反射面で検知部ハウジング８の上記軸線方向に反射された後に第２光ファイバ４０に導かれる。このように照射部１４からの照射角度及び受光部１６の光軸角度を検知部ハウジング８の軸線に対して所定角度傾斜させることによって、照射部１４からの測定光が直接的に受光部１６に受光されることがなく、測定領域５０からの被検知光のみが受光部１６に受光されるようになり、これにより流体中のダスト濃度を正確に測定することができる。また、受光部１６にて受光された被検知光を反射鏡５６により反射させているので、この被検知光を鋭角に反対方向に導いて第２光ファイバ４０の先端面に到達させることができ、これにより、検知部ハウジング８の外形を小さくすることが可能となり、その小型化、軽量化を達成することができる。尚、この形態では、検知部ハウジング８の凹部１５の軸線方向中央部には、外方に突出する遮光板８０が設けられている。この遮光板８０は、照射部１４から照射された測定光が受光部１６に直接的に受光されるのを確実に防止する。
【００４２】
このダスト測定装置には、更に、照射部１４の照射面（照射口カバー２０の表面）及び受光部１６の受光面（受光口カバー２４の表面）にダストが付着するのを防止するためのパージ機構が設けられている。図示のパージ機構は、照射部１４の照射面へのダスト、ミスト等の付着を防止するための第１パージ流体送給手段８２と、受光部１６の受光面へのダスト、ミスト等の付着を防止するための第２パージ流体送給手段８４とから構成され、第１パージ流体送給手段８２が第１パージ流体送給流路８６を備え、第２パージ流体送給手段８４が第２パージ流体送給流路８８を備えている。この実施形態では、第１及び第２パージ流体送給流路８６，８８は主パージ流体送給流路９０に合流され、この主パージ流体送給流路９０がパージ流体供給源９２に接続されている。パージ流体供給源９２は例えば流体タンクから構成され、この流体タンク内に流体流路４を通して流れる流体と実質上同じ成分の流体が充填され、かく充填されたパージ流体が後述する如くパージ供給される。流体流路４を通して燃料用ガス、例えば都市ガスが流れる場合、パージ流体供給源９２から実質上同じ成分の燃料用ガス、例えば都市ガスがパージ供給され、このようにパージ供給することによって、パージ流体が添加されても流体流路４を流れる流体の成分が変化することがなく、流体流路４を流れる燃料用ガスの燃焼熱量を一定に保つことができる。
【００４３】
この実施形態では、主パージ流体送給流路９０は、第１閉塞部材４２に形成された環状流路９６と、この環状流路９６から延びる流路９８と、第１閉塞部材４２に装着された接続部材１００の流路１０２と、検知部ハウジング８の端部部材１０４に形成された流路１０６と、端部部材１０４と接続部材１１０との間に配設された接続パイプ１１２の流路１１４と、を含み、この端部部材１０４の流路１０６がチューブ部材１１６の流路１１８を介してパージ流体供給源９２に接続される。
【００４４】
第１パージ流体送給流路８６は、第１閉塞部材４２に形成された流路１２０を含み、この流路１２０が上記環状流路９６から第１カバー取付部材４６まで延びている。また、第２パージ流路８８は、第１閉塞部材４２の環状流路９６から延びる流路１２２と、第１閉塞部材４２に装着された短接続部材１２４の流路１２６と、第２閉塞部材５２に装着された短接続部材１２８の流路１３０と、短接続部材１２４，１２８間に配設された接続パイプ１３２の流路１３４と、第２閉塞部材５２の流路１３６と、その環状流路１３８と、この環状流路１３８から第２カバー取付部材６４まで延びる流路１４０と、を含んでいる。このように構成されているので、パージ流体供給源９２からのパージ流体は、主パージ流体送給流路９０を通して第１閉塞部材４２の環状流路９６に流れ、この環状流路９６から第１パージ流体送給流路８６を通して第１カバー取付部材４６に向けて流れるとともに、第２パージ流体送給流路８８を通して第２カバー取付部材６４に向けて流れる。
【００４５】
この実施形態では、主パージ流体送給流路９０に逆止弁１４６が配設されている。この逆止弁１４６は、球状の弁体１４８と、この弁体１４８を押圧する押圧部材１５０と、押圧部材１５０に作用するコイルばね１５２から構成され、コイルばね１５２は、押圧部材１５０を介して弁体１４８を閉方向（図２において左方）に弾性的に偏倚する。このように逆止弁１４６を設けることによって、主パージ流体送給流路９０を通しての流体の逆流が防止され、流体流路４を流れる流体が第１パージ流体送給流路８６及び／又は第２パージ流体送給流路８８を通してパージ流体供給源９２側に逆流することが防止される。また、図示の形態では、押圧部材１５０の片側（弁体１４８に作用する面とは反対側）に軸部１５１が設けられ、この軸部を被嵌するようにコイルばね１５２が装着されているので、コイルばね１５２の偏倚力が押圧部材１５０を介して弁体１４８に安定的に作用し、かくして、主パージ流体送給流路９０を通しての流体の逆流をより確実に防止することができる。尚、第１及び第２パージ流体送給流路８６，８８に充分な設置スペースが存在する場合、このような逆止弁を第１及び第２パージ流体送給流路８６，８８に設けるようにしてもよい。
【００４６】
第１及び第２パージ流体送給流路８６，８８を流れるパージ流体は、次のようにして照射口カバー２０の照射面及び受光口カバー２４の受光面に向けて噴出される。第１及び第２カバー取付部材４６，６４は実質上同一の構成であり、以下、主として図４を参照して、第２カバー取付部材６４（第１カバー取付部材４６）及びそれに関連する構成について説明する。
【００４７】
受光口カバー２４（照射口カバー２０）の受光面（照射面）側に取り付けられる第２カバー取付部材６４（第１カバー取付部材４６）は、外周壁１６２と、この外周壁１６２の先端部から受光面（照射面）に向けて半径方向内方に傾斜して延びる内周壁１６４とを有し、外周壁１６２が第２閉塞部材５２（第１閉塞部材４２）に当接するように装着される。この取付状態においては、内周壁１６４の先端部が受光口カバー２４（照射口カバー２０）の受光面（照射面）を押圧し、受光口カバー２４（照射口カバー２０）は受光部１６の第２凹部（照射部１４の第１凹部）に押圧保持される。
【００４８】
この第２カバー取付部材６４（第１カバー取付部材４６）の外周壁１６２と内周壁１６４との間には第２環状空間１６６（第１環状空間）が規定され、かかる第２環状空間１６６（第１環状空間）が第２パージ流体送給流路８８（第１パージ流体送給流路８６）に連通している。また、この内周壁１６４の先端部には、周方向に間隔をおいて複数個の噴出口１７０が設けられている。この形態では、噴出口１７０は矩形状に形成されているが、半円状等の適宜の形状に形成することもできる。
【００４９】
このように構成されているので、第２パージ流体送給流路８８（第１パージ流体送給流路８６）からのパージ流体は、第２カバー取付部材６４（第１カバー取付部材４６）の第２環状空間１６６（第１環状空間）に流れ、この第２環状空間１６６（第１環状空間）を通して複数個の噴出口１７０から半径方向内方に受光口カバー２４（照射口カバー２０）の受光面（照射面）に沿って噴出される。
【００５０】
この実施形態では、更に、流体流路４を流れる流体が検知部ハウジング８内に流入するのを確実に防止するために、必要個所に、Ｏリング１８０を二重に用いた二重シール構造が採用されている。即ち、図２及び図３に示すように、この二重シール構造は、第１閉塞部材４２の装着部位、第２閉塞部材５２の装着部位、ファイバ保持部材４４の装着部位、短接続部材１２４，１２８の装着部位、保持ホルダ７６の装着部位、カバー保持部材６０の装着部位等に採用されている。
【００５１】
上述したダスト測定装置では、パージ流体供給源９２からのパージ流体が主パージ流体送給流路９０を通して第１及び第２パージ流体送給流路８６，８８に送給され、第１パージ流体送給流路８６に送給されたパージ流体は、第１カバー取付部材４６の噴出口から照射口カバー２０の照射面に向けて噴出されるとともに、第２パージ流体送給流路８８に送給されたパージ流体は、第２カバー取付部材６４の噴出口１７０から受光口カバー２４の受光面に向けて噴出される。従って、照射面付近のダスト、ミスト等は、第１カバー取付部材４６の噴出口から半径方向内方に流れた後に照射面から離れる方向へ流れるパージ流体によって吹き飛ばされ、また受光面付近のダスト、ミストは、第２カバー取付部材６４の噴出口１７０から半径方向内方に流れた後に受光面から離れる方向へ流れるパージ流体によって吹き飛ばされ、かくして、ダスト、ミスト等が照射面及び受光面に付着することが防止され、仮にダスト、ミスト等がこれらの面にに付着したとしても吹き飛ばすことができる。
【００５２】
このダスト測定装置では、照射口カバー２０、受光口カバー２４及び反射鏡５６は、次の通りにしてメンテナンス、交換を行うことができる。主として図３及び図５を参照して、照射口カバー２０については、取付ねじ（図示せず）を外すことにより第１カバー取付部材４６を検知部ハウジング８から取り外すことができ、これにより、図５に示すように、照射口カバー２０をその照射部１４の第１凹部から取り外すことができ、かくして、照射口カバー２０のメンテナンス（例えば、照射面の清掃等）、交換を容易に行うことができる。
【００５３】
また、受光口カバー２４については、照射口カバー２０と同様に、取付ねじ（図示せず）を外すことにより第２カバー取付部材６４を検知部ハウジング８から取り外すことができ、これにより、図５に示すように、受光口カバー２４をその受光部１６の第２凹部から取り外すことができ、かくして、受光口カバー２４のメンテナンス（例えば、照射面の清掃等）、交換を容易に行うことができる。
【００５４】
更に、検知部ハウジング８の第１及び第２ハウジング部材１１，１３の螺着を外すと、図５に示すように、第２ハウジング部材１３とともに受光部ホルダ５１、第２閉塞部材５２、レンズ支持スリーブ５８、カバー保持部材６０、集光レンズ５４、受光口カバー２４、第２カバー取付部材６４、鏡支持部材６８及び反射鏡５６が第１ハウジング部材１１側から分離し、この第１ハウジング部材１１側から取り外すことができる。そして、かく取り外した状態で取付用ねじ７１を緩めると、第２ハウジング部材１３側から受光部ホルダ５１及びこれに内蔵された各種部材（受光口カバー２４、反射鏡５６及びこれらに関連する部材）が第２ハウジング材１３から分離し、第２ハウジング部材１３側からこれらを取り外すことができる。この状態において、更に、第２閉塞部材５２を覆う受光部ホルダ５１を外した後に固定用ねじ７０を外すと、第２閉塞部材５２から鏡支持部材６８及びこれに取り付けられた反射鏡５６を取り外すことができ、このように取り外すことによって、反射鏡５６のメンテナンス、交換等容易に行うことができる。
【００５５】
次に、図６〜図１０を参照して、挿入管構造７（ボールバルブ部１０及びガスシール部１２（シール管を構成する））及びこれに関連する構成について説明する。流体配管２には接続部材２０２が接続され、この接続部材２０２にボールバルブ部１０が接続され、このボールバルブ部１０にガスシール部１２が接続されている。接続部材２０２は管状部材から構成され、その一端部の弧状部２０４が配管２の外周面に例えば融着される。この接続部材２０２の他端部には接続フランジ２０６が設けられている。ボールバルブ部１０は流路２０８を有するバルブハウジング２１０を有し、このバルブハウジング２１０の流路２０８にボールバルブ２１２が配設されている。ボールバルブ２１２には貫通孔２１４が設けられている。また、ボールバルブ２１２には軸部材２１６が固定され、軸部材２１６はバルブハウジング２１０から突出し、軸部材２１６の突出端部に操作ハンドル２１８が装着されている。バルブハウジング２１０の一端部には接続フランジ２２０が設けられ、接続部材２０２及びバルブハウジング２１０の接続フランジ２０６，２２０がボルト２２２及びナット２２４により相互に連結されている。
【００５６】
また、ガスシール部１２はシールハウジング２２６を備え、このシールハウジング２２６に挿入路２２８が設けられ、挿入路２２８はバルブハウジング２１０の流路２０８に連通している。シールハウジング２２６の一端部には接続フランジ２３０が設けられ、またバルブハウジング２１０の他端部にも接続フランジ２３２が設けられ、これら接続フランジ２３０，２３１がボルト２２２及びナット２２４により相互に連結されている。
【００５７】
この実施形態では、シールハウジング２２６の挿入路２２８の一端部（図６において右端部）には間隔をおいて一対の基部側シール部材２３２が配設され、またその挿入路２２８の他端部（図６において左端部）には間隔をおいて一対の先端側シール部材２３４が配設されている。これらシール部材２３２，２３４は、例えばゴム製のＯリング等から構成され、流体流路４を流れる流体が外部に漏れるのを防止する。
【００５８】
挿入路２２８の一対の基部側シール部材２３２の外側（図６において右側）には第１ダストシール部材２３６が配設され、また一対の先端側シール部材２３４の外側（図６において左側）には第２ダストシール２３８が設けられている。第１ダストシール部材２３４は、流体流路４を流れる流体中に含まれたダストが基部側シール部材２３２に侵入するのを防止し、また第２ダストシール部材２３８は、外部からのダストが先端側シール部材２３４に侵入するのを防止する。このように第１及び第２ダストシール部材２３６，２３８を設けることによって、後述する如くして検知部ハウジング８を流体流路４に挿入した状態において、基部側及び先端側シール部材２３２，２３４にダストが侵入するのを防止することができ、これらシール部材２３２，２３４の傷等の発生を防止し、長期にわたって所望のシール効果を保つことができる。
【００５９】
次に、流体流路４を流れる流体中のダスト濃度を測定するに際し、検知部ハウジング８の流体流路４への挿入操作について説明する。ボールバルブ部１０を閉状態に保持した状態（ボールバルブ２１２が流路２０８を閉塞する状態）において、まず、検知部ハウジング８の先端部を、図６に示すように、ガスシール部１２の挿入路２２８に挿入する。この挿入状態においては、検知部ハウジング８の凹部１５が一対の先端側シール部材２３４の配置部位に位置するが、このとき、検知部ハウジング８の第２ハウジング部材１３の円筒状部が一対の基部側シール部材２３２に位置し、従って、検知部ハウジング８の外周面とシールハウジング２２６の内周面との間は、一対の基部側シール部材２３２の二つのシール部材によりシールされる。
【００６０】
次に、操作ハンドル２１８を操作してボールバルブ部１０を開状態にし、ボールバルブ２１２の貫通孔２１４をバルブハウジング２１０の流路２０８に連通させる。そして、この状態にて検知部ハウジング８を矢印で示す挿入方向に挿入すると、図７に示すように、検知部ハウジング８の凹部１５が一対の基部側シール部材２３２と一対の先端側シール部材２３４との間に位置するようになり、これに対応して、検知部ハウジング８の第２ハウジング部材１３の円筒状部が一対の基部側シール部材２３２に位置するとともに、その第１ハウジング部材１１の円筒状部が一対の先端側シール部材２３４に位置し、従って、検知部ハウジング８の外周面とシールハウジング２２６の内周面との間は、一対の基部側シール部材２３２及び一対の先端側シール部材２３４の４つのシール部材によりシールされる。
【００６１】
この状態から検知部ハウジング８を矢印で示す挿入方向に更に挿入すると、図８に示すように、検知部ハウジング８の凹部１５が内側の基部側シール部材２３２に位置するようになるが、このとき、検知部ハウジング８の第２ハウジング部材１３の円筒状部が外側の基部側シール部材２３２に位置するとともに、その第１ハウジング部材１１の円筒状部が一対の先端側シール部材２３４に位置し、従って、検知部ハウジング８の外周面とシールハウジング２２６の内周面との間は、外側の基部側シール部材２３２及び一対の先端側シール部材２３４の３つのシール部材によりシールされる。
【００６２】
そして、この状態から検知部ハウジング８を矢印で示す方向に更に挿入すると、図９に示すように、検知部ハウジング８の凹部１５が一対の基部側シール部材２３２の内側に位置するが、このとき、検知部ハウジング８の第１ハウジング部材１１の円筒状部が一対の先端側シール部材２３４に位置し、従って、検知部ハウジング１１の外周面とシールハウジング２２６の内周面との間は、一対の先端側シール部材２３４の二つのシール部材によりシールされる。
【００６３】
その後、更に検知部ハウジング８を矢印で示す挿入方向に挿入すると、図１０に示すように、検知部ハウジング８の凹部１５は一対の基部側シール部材２３２の内側に位置し、これに対応して、検知部ハウジング８の第１ハウジング部材１１の円筒状部が一対の基部側シール部材２３２及び一対の先端側シール部材２３４に位置し、従って、検知部ハウジング８の外周面とシールハウジング２２６の内周面との間は、一対の基部側シール部材２３２及び一対の先端側シール部材２３４の４つのシール部材によりシールされ、このシール状態を維持しながら矢印の方向に所定位置まで挿入される。
【００６４】
この実施形態では、検知部ハウジング８の先端部はシールハウジング２２６の挿入路２２８、バルブハウジング２１０の流路２０８、ボールバルブ２１２の貫通孔２１４及び接続部材２０２内の空間を通して流体流路４の所定部位まで挿入される。そして、この挿入時、上述したように、一対の基部側シール部材２３２及び一対の先端側シール部材２３４のうちの少なくとも二つのシール部材が、検知部ハウジング８とシールハウジング２２６との間の間隙を二重にシールし、流体流路を高圧の流体が流れていてもその漏れを確実に防止することができる。
【００６５】
このようなダスト測定装置においては、次のように構成して測定値の校正を行うようにするのが望ましい。尚、この変形形態の検知部ハウジングにおいて、図１〜図１０に示す実施形態と実質上同一の部材には同一の参照番号を付して説明する。
【００６６】
図１１〜図１３を参照して、測定値の校正を行う場合、図１１に示すように、校正ユニット２５２が検知部ハウジング８の先端部に装着される。図示の校正ユニット２５２は中空円筒状のユニットハウジング２５４を備え、その両端部に端壁２５６，２５８が設けられている。一方端壁２５６の中央部には第１開口２６０が設けられ、この第１開口２６０の両側に第２開口２６４（図１３において一方のみ示す）が設けられ、第２開口２６４の開口部はテーパ状に延びるテーパ部２６６が設けられている（図１３参照）。また、他方の端壁２５８には、検知部ハウジング８の外径に対応する挿入開口２６８が設けられている。
【００６７】
また、検知部ハウジング８の受光部ホルダ５１には一対のねじ軸２７０（図１２参照）が固定されている。第２ハウジング部材１３の端壁２７２には一対の開口２７３が設けられており、各ねじ軸２７０は対応する開口２７３を通して外方に突出している。
【００６８】
このユニットハウジング２５４は、次の通りにして検知部ハウジング８に取り付けられる。即ち、検知部ハウジング８をユニットハウジング２５４の端壁２５８の挿入開口２６８を通して挿入し、第２ハウジング部材１３から突出する一対のねじ軸２７０をその端壁２５６の第２開口２６４を通して挿通させ、その後、ユニットハウジング２５４の端壁２５６から突出するねじ軸２７０の突出端部に締付けねじ２７１を螺着して締め付ける。かく締め付けると、ユニットハウジング２５４の端壁２５６が検知部ハウジング８の端壁２７２に当接し、これによって、ユニットハウジング２５４の軸線方向（図１１において左右方向）の位置決めが行われる。また、ユニットハウジング２５４の他端側においては、端壁２５８が検知部ハウジング８に被嵌され、これによって、検知部ハウジング８に対して同心状に位置決めされる。また、ユニットハウジング２５４の一端側においては、第２開口２６４のテーパ部２６６に対応して締付けねじ２７１に設けられたテーパ部２７４が、対応する第２開口２６４のテーパ部２６６に嵌り込むようになり、これによって、検知部ハウジング８に対して同心状に位置決めされ、このように装着した状態では、取付用ねじ７１の頭部は、ユニットハウジング２５４の端壁２５６の第１開口２６０内に位置する。このように位置決め固定されるので、ねじ軸２７０及び締付けねじ２７１が芯出し固定機構を構成し、この芯出し固定機構によって、ユニットハウジング２５４を検知部ハウジング８の先端部に正確に位置決め固定することができる。
【００６９】
このユニットハウジング２５４の所定部位には取付部２７８が設けられ、この取付部２７８に標準部材２８０が取り付けられる。この形態では、取付部２７８は中空円筒状の案内取付部材２８２から構成され、案内取付部材２８２がユニットハウジング２５４の側面に固定され、この案内取付部材２８２の内周面には軸線方向に延びる案内溝２８３が設けられている。また、案内取付部材２８２に対応して、ユニットハウジング２５４の側面には矩形状の挿通孔２８４が形成されている。一方、標準部材２８０は、円筒状の本体部２８６と、この本体部２８６の先端に設けられた標準検知部２８８とを有し、プレート状の標準検知部２８８には、測定値を校正する際の基準となるダスト模様が施されている。また、本体部２８６の周面には、被案内突起２９０が設けられている。
【００７０】
この標準部材２８０は、案内取付部材２８２内に挿入することによって取り付けられる。このとき、本体部２８６の被案内突起２９０は案内取付部材２８２の案内溝２８３内に挿入され、この案内溝２８３に沿って案内される。かく装着すると、本体部２８６の先端面がユニットハウジング２５４の外周面に当接し、これによって標準部材２８０の挿入方向の位置決めが行われ、標準検知部２８８はユニットハウジング２５４の挿通孔２８４を通してユニットハウジング２５４内に突出して測定領域５０に位置付けられる。また、被案内突起２９０が案内溝２８３内に位置するので、標準部材２８０のユニットハウジング２５４（即ち、検知部ハウジング８）に対する相対的角度の位置決めが行われる。従って、ユニットハウジング２５４を検知部ハウジング８の先端部に上述したように装着した後、標準部材２８０を上述したように取り付けることによって、検知部ハウジング８に対して標準部材２８０の標準検知部２８８を所定の位置関係に、即ち所定の測定領域５０に正確に位置付けることができ、その結果、標準部材２８０を用いた測定値の校正を正確に行うことができる。
【００７１】
次に、図１４〜図１６を参照して、ダスト測定装置の他の形態について説明する。図１４は、他の実施形態のダスト測定装置の検知ユニットを収納した状態で示す断面図であり、図１５は、図１４のダスト測定装置の検知ユニットに接続ユニットを接続する前の状態を示す断面図であり、図１６は、図１４のダスト測定装置の検知ユニットに接続ユニットを接続した状態を示す断面図である。尚、以下の実施形態において、図１〜図１０に示す実施形態と実質上同一のものには同一の番号を付し、その説明を省略する。
【００７２】
図１４〜図１６を参照して、この他の実施形態のダスト測定装置は、検知ユニット３０２と、この検知ユニット３０２の後端部に着脱自在に接続される接続ユニット３０４とを備えている。この検知ユニット３０２は検知部ハウジング３０６を備え、検知部ハウジング３０６の先端部に設けられた凹部３０８の一端側に照射部１４が設けられ、その他端側に受光部１６が設けられている。検知部ハウジング３０６の後部には、環状凹部３１０が設けられている。この検知ユニット３０２のその他の構成は、図１〜図９に示す実施形態における検知部ハウジング８及びそれに関連する構成と実質上同一である。
【００７３】
接続ユニット３０４は接続部ハウジング３１２を備え、その先端部に接続突部３１４を有し、その後端部に後端部材３１６が装着されている。接続部ハウジング３１２は中空部材から構成され、図１６に示すように、第１光ファイバ３８Ａ及び第２光ファイバ４０Ａが挿通される空間が存在するとともに、検知部ハウジング３０６内のパージ流路に接続されるパージ流路用細管３１８が内蔵され、パージ流路用細管３１８は、パージ流体を供給するパージ流体供給源（図示せず）に接続される。
【００７４】
この接続部ハウジング３１２の軸線方向略中央部に環状凹部３２０が設けられている。この環状凹部３２０に対応して、接続部ハウジング３１２内には支持部材３２２が装着され、この支持部材３２２には、第１及び第２光ファイバ３８Ａ，４０Ａを挿通するための挿通孔が設けられているとともに、パージ流路用細管３１８の端部が支持されている。また、接続部ハウジング３１２の後端部には押しハンドル３２４が設けられている。更に、後端部材３１６には、第１及び第２光ファイバ３８Ａ，４０Ａを導出するための導出孔が設けられている。
【００７５】
この検知ユニット３０２及び接続ユニット３０４は、流体配管２に接続された挿入管構造７Ａを通して挿入される。図示の実施形態における挿入管構造７Ａの基本的構造は、図６に示すものと実質上同一であるが、ガスシール部１２Ａ（シール管）のシールハウジング２２６の端部（後端部）にファイバ収容部３２６が設けられ、またシールハウジング２２６にロック手段３２８が設けられ、ロック手段３２８はシールハウジング２２６に螺着されたロックねじ３３０から構成されている。
【００７６】
この実施形態では、第１及び第２光ファイバ３８Ａ，４０Ａの基部側は接続ユニット３０４を通して発光源及び受光素子（図示せず）に接続されるように構成されており、このことに関連して、検知ユニット３０２の後端側（基部側）から延びる第１及び第２光ファイバ３８Ａ，４０Ａの一部がこのファイバ収容部３２６内に収容される。ダスト濃度を測定しないときには、図１４に示すように、検知ユニット３０２は挿入管構造７Ａ内に、即ち接続部材２０２、ボールバルブ部１０及びガスシール部１２内に収容保持され、ロックねじ３３０の先端部が検知部ハウジング３０６の環状凹部３１０に係合することによって、この収容状態にロック保持される。この収容状態においては、検知ユニット３０２の先端部が流路配管２内に突出せず、流体流路４を流れる流体の抵抗になることはない。
【００７７】
この収容状態において、検知ユニット３０２から延びる第１及び第２光ファイバ３８Ａ，４０Ａの一部は、ファイバ収容部３２６内にリング状にして収容され、例えば、破損防止保持片３３２に所要の通りにリング状に巻き掛けることによって収納される。尚、ファイバ収容部３２６の一端は、プレート状の蓋部材３３４によって密封され、このように密封することによって、流体流路４を流れる流体の挿入管構造７Ａを通しての外部への漏出を確実に防止することができる。
【００７８】
次に、このダスト測定装置によるダスト測定について説明すると、ダスト濃度を測定する際には、図１５に示すように、蓋部材３３４を取り外してファイバ収容部３２６を開放し、ファイバ収容部３２６に収容された第１及び第２光ファイバ３８Ａ，４０Ａの一部を取り出す。尚、このとき、破損防止保持片３３２が邪魔になるときには、それらの一部を取り外すようになるが、これら破損防止保持片３２２をファイバ収容部３２６に着脱自在に装着される保持具（図示せず）に取り付けるようにすれば、この保持具を取り外すようにすればよい。
【００７９】
次いで、第１及び第２光ファイバ３８Ａ，４０Ａを接続ユニット３０４の一端部（接続突部３１４）側から他端（後端部材３１６）側に接続部ハウジング３１２を通し、この挿通した状態で、接続ユニット３０４の押しハンドル３１６を矢印３４０で示す挿入方向に押圧してその先端側を挿入管構造７Ａ（ガスシール部１２Ａ）に挿入して検知ユニット３０２の後端部に接続ユニット３０４の先端部を着脱自在に接続する。このような接続は、例えば、検知部ハウジング３０６の後端部に接続用溝を設けるとともに、接続部ハウジング３１２の先端部に接続用ピンを設け、かかる接続用ピンを上記接続用溝に係合することによって行うことができる。このように接続すると、接続ユニット３０４のパージ用細管３１８が検知ユニット３０２のパージ流路（図示せず）に接続される。
【００８０】
その後、ロックねじ３３０を緩めてロック手段３２８によるロック状態を解除し、押しハンドル３２４を更に矢印３４０で示す方向に押して検知ユニット３０２及び接続ユニット３０４を挿入し、図１６に示すように、検知ユニット３０２の照射部１４及び受光部１６が流体流路４の所定測定領域に達するまで挿入すると、ロックねじ３３０を締め付けてその先端部を接続ユニット３０６の環状凹部３２０に係合する。かくすると、ロック手段３２８がロック状態になり、検知ユニット３０２及び接続ユニット３０４が図１６に示す状態にロック保持される。その後更に、接続ユニット３０４を通して延びる第１及び第２光ファイバ３８Ａ，４０Ａの端部を発光源（図示せず）及び受光素子（図示せず）に接続し、このようにして測定の準備作業を行い、この準備作業の後に流体流路４を流れる流体中のダスト濃度を上述したようにして測定することができる。
【００８１】
尚、ダスト濃度の終了後は、上述したと反対に、ロックねじ３３０を緩める。かくすると、流体流路４を流れる流体の圧力によって、検知ユニット３０２及び接続ユニット３０４が外側に押し出される。そして、所定位置まで押し出されると、ロックねじ３３０を締め付け、その先端部を検知ユニット３０２の環状凹部３１０に係合し、検知ユニット３０２を挿入管構造７Ａ内に収容された状態でロック保持する。次に、接続ユニット３０４を検知ユニット３０２から取り外し、更に第１及び第２光ファイバ３８Ａ，４０Ａを接続ユニット３２６から外してファイバ収容部３２６に収容し、その後、ファイバ収容部３２６の開口部に蓋部材３３４を取り付ける。かくすると、図１４に示すように、検知ユニット３０２が挿入管構造７Ａ内に、また第１及び第２光ファイバ３８Ａ，４０Ａの一部がファイバ収容部３２６内に収容され、これらを流体配管２の所定部位に取り付けた状態で保管される。
【００８２】
この実施形態では、接続ユニット３０４を一つ接続しているが、複数個の接続ユニット３０４を接続するようにしてもよい。この場合、検知ユニット３０２と接続ユニット３０４との間に一つ又は二つ以上の中間接続ユニット（図示せず）が接続され、各中間ユニットの先端側の構造は、上述した接続ユニット３０４の先端側の構造と略同様でよく、その後端側の構造は、上述した検知ユニット３０２の後端側の構造と略同様でよい。
【００８３】
次に、図１７〜図２０を参照して、ダスト測定装置の更に他の形態について説明する。図１７は、更に他の実施形態のダスト測定装置の検知ユニットを収納した状態で示す断面図であり、図１８は、図１７のダスト測定装置の検知ユニットに接続ユニットを接続する前の状態を示す断面図であり、図１９は、図１７のダスト測定装置の検知ユニットと接続ユニットの接続部を示す部分断面図であり、図２０は、図１７のダスト測定装置の検知ユニットに接続ユニットを接続した状態を示す断面図である。
【００８４】
図１７〜図２０を参照して、この更に他の実施形態のダスト測定装置は、検知ユニット３０２Ｂと、この検知ユニット３０２Ｂの後端部に着脱自在に接続される中間接続ユニット３０４Ｂと、この中間接続ユニット３０４Ｂの後端部に着脱自在に装着される後接続ユニット４０４とを備え、第１及び第２光ファイバ３８Ｂ，４０Ｂが検知ユニット３０２Ｂ、中間接続ユニット３０４Ｂ及び後接続ユニット４０４内に内蔵されている。
【００８５】
この検知ユニット３０２Ｂは検知部ハウジング３０６Ｂを備え、検知部ハウジング３０６Ｂの先端部に設けられた凹部３０８の一端側に照射部１４が設けられ、その他端側に受光部１６が設けられている。この検知ユニット３０２Ｂには、第１光ファイバ３８Ｂの照射側第１ファイバ部材３５２及び及び第２光ファイバ４０Ｂの受光側第１光ファイバ部材３５４が内蔵されている。照射側第１ファイバ部材３５２の一端部は照射部１４に延び、その他端部は検知部ハウジング３０６Ｂの後端部に延び、この他端部に接続部材３５６が設けられている。また、受光側第１ファイバ部材３５４の一端部は受光部１６近傍まで延び、その他端部は検知部ハウジング３０６Ｂの後端部に延び、この他端部に接続部材３５８が設けられている。更に、検知部ハウジング３０６Ｂの後部には、環状凹部３１０が設けられている。この検知ユニット３０２Ｂのその他の構成は、図１〜図９に示す実施形態における検知部ハウジング８及びそれに関連する構成と実質上同一である。
【００８６】
中間接続ユニット３０４Ｂは接続部ハウジング３１２Ｂを備え、その先端部に接続突部３１４を有し、その後端部に後端部材３１６が装着されている。この接続ユニット３０４Ｂには、第１光ファイバ３８Ｂの照射側第２ファイバ部材３６０及び及び第２光ファイバ４０Ｂの受光側第２光ファイバ部材３６２が内蔵されている。照射側及び受光側第２ファイバ部材３６０、３６２の一端部は接続部ハウジング３１２Ｂの接続突部３１４に延び、これらの一端部に接続部材３６４，３６６が設けられており、またそれらの他端部は接続部ハウジング３１２Ｂの後端部に延び、これらの他端部に接続部材３６８，３７０が設けられている。更に、接続部ハウジング３１２Ｂの後部には、環状凹部３２０が設けられている。この中間接続ユニット３０４Ｂのその他の構成は、図１４〜図１７に示す実施形態における接続ユニット３０４の構成と略同一である。
【００８７】
後接続ユニット４０４は接続部ハウジング４１２を備え、その先端部に接続突部４１４を有し、その後端部に後端部材４１６が装着されている。この後接続ユニット４０４には、第１光ファイバ３８Ｂの照射側第３ファイバ部材３７２及び及び第２光ファイバ４０Ｂの受光側第３光ファイバ部材３７４が内蔵されている。照射側及び受光側第３ファイバ部材３７２，３７４の一端部は接続部ハウジング４１２の接続突部４１４に延び、これらの一端部に接続部材３７６，３７８が設けられており、またそれらの他端部は後端部材４１６を通して外側に延び、それらの他端部に接続部材３８０，３８２が設けられている。更に、後端部材４１６には、この後接続ユニット４０４を矢印３８４で示す挿入方向に押すための押しハンドル３８６が設けられている。この後接続ユニット４０４のその他の構成は、中間接続ユニット３０４Ｂと略同一である。
【００８８】
この検知ユニット３０２Ｂ、中間接続ユニット３０４Ｂ及び後接続ユニット４０４は、流体配管２に接続された挿入管構造７Ｂを通して挿入される。図示の実施形態における挿入管構造７Ｂの基本的構造は、図１４〜図１７に示すものと略同一で、ガスシール部１２Ｂにロック手段３２８を構成するロックねじ３３０が設けられているが、ファイバ収容部を設けることに代えて、ガスシール部１２Ｂ（シール管）のシールハウジング２２６の端部（後端部）にフランジ３８８が設けられ、このフランジ３８８にボルト３９０及びナット３９２により閉塞部材３９４が密封装着される。
【００８９】
次に、このダスト測定装置によるダスト測定について説明すると、ダスト濃度を測定する際には、図１８に示すように、蓋部材３９４を取り外して挿入管構造７Ｂの挿入側を開放し、中間接続ユニット３０４Ｂの先端側を挿入管構造７Ｂ内に挿入してそれに保持された検知ユニット３０２Ｂの後端部に接続し、更にこの中間接続ユニット３０４Ｂの後端部に後接続ユニット４０４の先端部を接続する。中間接続ユニット３０４Ｂの接続突部３１４を検知ユニット３０２Ｂの後端部に挿入して接続すると、図１９から理解されるように、中間接続ユニット３０４Ｂ側の接続部材３６４，３６６が検知ユニット３０２Ｂ側の接続部材３５６，３５８内に受け入れられ、これによって、中間接続ユニット３０４Ｂ側の照射側及び受光側の第２ファイバ部材３６０，３６２と、検知ユニット３０２Ｂ側の照射側及び受光側の第１ファイバ部材３５２，３５４とが相互に接続される。また、逆止弁３９６が内蔵された検知ユニット３０２Ｂ側のパージ流路３９７と中間接続ユニット３０４Ｂに内蔵されたパージ用細管３９８とが接続される。また、後接続ユニット４０４の接続突部４１４を中間接続ユニット３０４Ｂの後端部に挿入して接続すると、検知ユニット３０２Ｂと中間接続ユニット３０４Ｂとの接続と同様にして、後接続ユニット４０４側の照射側及び受光側の第３ファイバ部材３７２，３７４と、中間接続ユニット３０４Ｂ側の照射側及び受光側の第２ファイバ部材３６０，３６２とが相互に接続されるとともに、後接続ユニット４０４に内蔵されたパージ用細管（図示せず）と中間接続ユニット３０４Ｂに内蔵されたパージ用細管３９８とが接続される。
【００９０】
このように接続した後、ロックねじ３３０を緩めてロック手段３２８によるロック状態を解除し、後接続ユニット４０４の押しハンドル４１６を矢印３８４で示す挿入方向に押し、図２０に示すように、検知ユニット３０２Ｂの照射部１４及び受光部１６が流体流路４の所定測定領域に達するまで挿入すると、ロックねじ３３０を締め付けてその先端部を中間接続ユニット３０４Ｂの環状凹部３２０に係合する。かくすると、ロック手段３２８がロック状態になり、検知ユニット３０２Ｂ、中間接続ユニット３０４Ｂ及び後接続ユニット４０４が図２０に示す状態にロック保持される。その後更に、後接続ユニット４０４を通して延びる照射側及び受光側の第３ファイバ部材３７２，３７４の端部を発光源（図示せず）及び受光素子（図示せず）に接続し、このようにして測定の準備作業を行い、この準備作業の後に流体流路４を流れる流体中のダスト濃度を測定する。
【００９１】
尚、ダスト濃度の終了後は、上述したと反対に、ロックねじ３３０を緩める。かくすると、流体流路４を流れる流体の圧力によって、検知ユニット３０２Ｂ、中間接続ユニット３０４Ｂ及び後接続ユニット４０４が外側に押し出される。そして、所定位置まで押し出されると、ロックねじ３３０を締め付け、その先端部を検知ユニット３０２Ｂの環状凹部３１０に係合し、検知ユニット３０２Ｂを挿入管構造７Ｂ内に収容された状態でロック保持する。そして、後接続ユニット４０４及び中間接続ユニット３０４Ｂを順次に取り外し、その後、ガスシール部１２Ｂのフランジ３８８に蓋部材３９４を取り付ける。かくすると、図１７に示すように、検知ユニット３０２Ｂが挿入管構造７Ｂ内に収容した状態で保管することができる。
【００９２】
この実施形態では、検知ユニット３０２Ｂに接続ユニット３０４Ｂ，４０４を接続しているが、一つ又は三つ以上の接続ユニットを接続するようにしてもよく、一つ接続する場合、後接続ユニット４０４を図１４〜図１７に示す接続ユニットにように構成すればよく、また三つ以上接続する場合、後接続ユニット４０４を一つとし、残りを中間接続ユニット３０４Ｂにすればよい。
【００９３】
上述した各種実施形態では、挿入管構造７Ａ（７Ｂ）に保持された検知ユニット３０２（３０２Ｂ）の照射部１４及び受光部１６に流体流路４を流れる流体が流れ、流体中のダストなどが照射部１４及び受光部に付着するおそれがあり、このような不都合を解消するために、例えば、図２１、図２２又は図２３に示すように構成することができる。
【００９４】
図２１に示す構造では、円筒スリーブ状の保護管５０２が用いられ、この保護管５０２がボールバルブ部１０のバルブハウジング２１０から接続部材２０２にわたって設けられている。検知ユニット３０２（３０２Ｂ）はこの保護管５０２の内側に配設され、保護管５０２の先端部内周面には一対のシール部材５０４が装着され、シール部材５０４は例えば０リングから構成される。
【００９５】
このように構成されるので、ダスト濃度を測定しないときには、検知ユニット３０２（３０２Ｂ）は、図２１に示すように、挿入管構造７Ａ（７Ｂ）内にロック保持され、かかる保持状態においては、一対のシール部材５０４は検知部ハウジング３０６（３０６Ｂ）の先端部に作用して保護管５０２と検知部ハウジング３０６（３０６Ｂ）との間をシールする。このとき、検知ユニット３０２（３０２Ｂ）の照射部１４及び受光部１６は一対のシール部材５０４の内側（挿入管機構７Ａ（７Ｂ））側に位置して保護管５０２により覆われており、従って、流体流路４を流れる流体は照射部１４及び受光部１６側に流入することがなく、照射部１４及び受光部１６のダストによる汚れを防止することができる。尚、ダスト濃度を測定するときには、検知ユニット３０２（３０２Ｂ）の先端側は、かかる一対のシール部材５０４の内側を通って流体流路４内に突出する。
【００９６】
図２２に示す構造では、円筒スリーブ状の保護管５１２が用いられ、この場合にも、保護管５１２がボールバルブ部１０のバルブハウジング２１０から接続部材２０２にわたって設けられる。検知ユニット３０２（３０２Ｂ）はこの保護管５１２の内側に配設され、保護管５１２の先端部には蓋部材５１４が開閉自在に設けられ、この蓋部材５１４は、例えばばね部材（図示せず）によって、保護管５１４の先端開口を密封状態保持する。
【００９７】
このように構成されるので、ダスト濃度を測定しないときには、検知ユニット３０２（３０２Ｂ）は、図２２に示すように、挿入管構造７Ａ（７Ｂ）内にロック保持され、かかる保持状態においては、蓋部材５１４は保護管５１２の先端開口を密封する。このとき、検知ユニット３０２（３０２Ｂ）の照射部１４及び受光部１６は蓋部材５１４の内側（挿入管機構７Ａ（７Ｂ））側に位置しており、従って、流体流路４を流れる流体は照射部１４及び受光部１６側に流入することがなく、このように構成しても照射部１４及び受光部１６のダストによる汚れを防止することができる。尚、ダスト濃度を測定するときには、検知ユニット３０２（３０２Ｂ）が挿入方向に押し出され、これによって、蓋部材５１４は矢印５１６で示す方向に二点鎖線で示す開放位置まで回動して保護管５１２の先端開口を開放し、かく開放された先端開口を通して検知ユニット３０２（３０２Ｂ）の先端側は流体流路４内に突出する。
【００９８】
図２３に示す構造では、円筒スリーブ状の保護管５２２が用いられ、この場合には、保護管５２２が検知ユニット３０２（３０２Ｂ）の検知部ハウジング３０６（３０６Ｂ）に相対的に回動自在に被嵌される。この保護管５２２の所定部位には、検知ユニット３０２（３０２Ｂ）の照射部１４及び受光部１６に対応して測定開口５２４が設けられ、図２３に示す閉角度位置に位置するときには、測定開口５２４は検知ユニット３０２（３０２Ｂ）の照射部１４及び受光部１６と反対側に位置し、この閉角度位置から１８０度回動した開角度位置においては、この測定開口５２４は照射部１４及び受光部１６に対向して位置する。
【００９９】
このように構成されるので、ダスト濃度を測定しないときには、検知ユニット３０２（３０２Ｂ）は、図２３に示すように、挿入管構造７Ａ（７Ｂ）内にロック保持されるとともに、保護管５２２が図２３に示す閉角度位置に保持される。かかる保持状態においては、保護管５２２が検知ユニット３０２（３０２Ｂ）の照射部１４及び受光部１６を覆い、流体流路４を流れる流体が照射部１４及び受光部１６側に流入するのを防止することができる。尚、ダスト濃度を測定するときには、保護管５２２が上記閉角度位置から１８０度回動した開角度位置に保持され、これによって、検知ユニット３０２（３０２Ｂ）の照射部１４及び受光部１６は外側に露出され、流体流路４内を流れる流体のダスト濃度を測定することができる。
【０１００】
以上、本発明に従うダスト測定装置の実施形態について説明したが、本発明はかかる実施形態に限定されるものではなく、本発明の範囲を逸脱することなく種々の変形乃至修正が可能である。
【０１０１】
例えば、図示のダスト測定装置の実施形態では、検知部ハウジング８の先端側に受光部１６を配置したことに関連して、受光部１６にて受光した被検知光を第２光ファイバ４０に導くために反射鏡５６を用いているが、これとは反対に、照射部を検知部ハウジングの先端側に配置するように構成した場合、第１光ファイバからの測定光を照射部に導くために反射鏡を用いるようになる。
【０１０２】
また、例えば、図示のダスト測定装置においては、締付けねじ２７１のテーパ部２７４を利用してユニットハウジング２５４を検知部ハウジング８に対して同心状に位置決め固定しているが、このような構成に限定されず、芯出し固定機構として、例えば、ばね付勢された位置決めロック片を用いるようにしてもよい。
【０１０３】
本発明の請求項１のダスト測定装置によれば、測定光の伝送は第１光ファイバにより行われ、また被検知光の伝送は第２光ファイバにより行われるので、検知部ハウジングの外形を小さく細くすることができる。また、検知部ハウジングの凹部の片側に照射開口が設けられ、その他側に受光開口が設けられ、照射開口及び受光開口は検知部ハウジングの軸線方向に対向しているので、これによっても、検知部ハウジングの外形を効果的に小さくすることができる。更に、照射手段及び受光手段の一方が反射鏡を含んでいるので、測定光又は被検知光を伝送する際に第１光ファイバ又は第２光ファイバを曲げることなく、測定光又は被検知光を反対方向に反射させて伝送させることができ、これによって、検知部ハウジングの外形を更に小さく細くすることができ、これによって、検知部ハウジングの挿入を容易にし、小径の孔を通して流体流路に挿入することが可能になるとともに、小径の流体流路を流れる流体中のダスト濃度を測定することが可能となる。更に発光源からの測定光は、照射開口から検知部ハウジングの軸線方向に対して１０〜３０度傾斜して測定領域に向けて照射され、また測定領域からの被検知光は、検知部ハウジングの軸線方向に対して１０〜３０度傾斜して前記反射鏡に導かれるので、検知部ハウジングの外形を小さくすることができるとともに、照射開口からの照射光が直接的に受光開口を通して受光されることを防止することができる。加えて、検知部ハウジングが挿入されるシール管の挿入路の一端部には一対の基部側シール部材が設けられ、その他端部側には一対の先端側シール部材が設けられているので、凹部を有する検知部ハウジングを挿入路を通して流体流路に挿入しても、少なくとも２つのシール部材がシール管の内周面と検知部ハウジングの外周面との間をシールし、かくして、流体の挿入路を通しての漏れを確実に防止することができる。
また、本発明の請求項２に記載のダスト測定装置によれば、照射手段、受光手段及び検知ハウジングに関する構成が上述したダスト測定装置と実質上同一であるので、請求項１に記載のダスト測定装置と同様の効果が達成される。加えて、ユニットハウジングは検知部ハウジングに装着され、この装着は芯出し固定機構により行われるので、検知部ハウジングに対してユニットハウジングを同心状に位置決め固定することができる。従って、かく固定した状態において、標準部材をユニットハウジングに装着すると、標準部材の標準検知部が測定領域に正確に位置付けられ、かくして、標準部材を用いての測定値の校正を正確に行うことができる。
【０１０４】
また、本発明の請求項３に記載のダスト測定装置によれば、受光開口を通して導入された被検知光は、反射鏡により反対側に反射され、第２光ファイバを通して受光素子に導かれるので、受光手段に関連して検知部ハウジングを小型化することができる。
【０１０５】
また、本発明の請求項４のダスト測定装置によれば、検知部ハウジングから照射口カバー及び受光口カバーを取り外すことができ、これらのメンテナンス、交換を容易に行うことができる。また、検知部ハウジングは相互に着脱自在に装着される第１及び第２ハウジング部材から構成され、この第２ハウジング部材に反射鏡が着脱自在に装着されているので、第２ハウジング部材から反射鏡も取り外すことができ、反射鏡のメンテナンス、交換をも容易に行うことができる。
【図面の簡単な説明】
【図１】本発明に従うダスト測定装置の一実施形態の全体を示す概略図である。
【図２】図１のダスト測定装置の一部を示す部分断面図である。
【図３】図１のダスト測定装置の照射部及び受光部付近を示す部分断面図である。
【図４】図１のダスト測定装置の受光部を拡大して示す部分拡大断面図である。
【図５】図１のダスト測定装置の照射部及び受光部付近を一部分解して示す分解断面図である。
【図６】図１のダスト測定装置の検地部ハウジングを流体流路に挿入するときの状態を示す断面図である。
【図７】図６の状態から検知部ハウジングを少し挿入した状態を示す部分断面図である。
【図８】図７に示す状態から検知部ハウジングを少し挿入した状態を示す部分断面図である。
【図９】図８に示す状態から検知部ハウジングを少し挿入した状態を示す部分断面図である。
【図１０】図９に示す状態から検知部ハウジングを更に少し挿入した状態を示す部分断面図である。
【図１１】変形形態の検知部ハウジングにユニットハウジングを装着した状態を示す部分断面図である。
【図１２】検知部ハウジングにユニットハウジングを取り付けた状態を示す右側面図である。
【図１３】図１２におけるＸＩＩＩ−ＸＩＩＩ線による断面図である。
【図１４】ダスト測定装置の他の実施形態における検知ユニットを収納した状態で示す断面図である。
【図１５】図１４のダスト測定装置の検知ユニットに接続ユニットを接続する前の状態を示す断面図である。
【図１６】図１４のダスト測定装置の検知ユニットに接続ユニットを接続した状態を示す断面図である。
【図１７】ダスト測定装置の更に他の実施形態における検知ユニットを収納した状態で示す断面図である。
【図１８】図１７のダスト測定装置の検知ユニットに接続ユニットを接続する前の状態を示す断面図である。
【図１９】図１７のダスト測定装置の検知ユニットと接続ユニットの接続部を示す部分断面図である。
【図２０】図１７のダスト測定装置の検知ユニットに接続ユニットを接続した状態を示す断面図である。
【図２１】検知ユニットへのダスト進入防止構造の一実施形態を示す部分断面図である。
【図２２】検知ユニットへのダスト進入防止構造の他の実施形態を示す部分断面図である。
【図２３】検知ユニットへのダスト進入防止構造の更に他の実施形態を示す部分断面図である。
【符号の説明】
２流体配管
４流体流路
６ダスト
７，７Ａ，７Ｂ挿入管構造
８検知部ハウジング
１０ボールバルブ部
１２，１２Ａ，１２Ｂガスシール部
１４照射部
１６受光部
２０照射口カバー
２４受光口カバー
２６測定装置本体
２８発光源
３０受光素子
３２ダスト濃度演算手段
３８，３８Ａ，３８Ｂ，４０，４０Ａ，４０Ｂ光ファイバ
４６，６４カバー取付部材
５０測定領域
５４集光レンズ
５６反射鏡
２２６シールハウジング
２３２基部側シール部材
２３４先端側シール部材
２３６，２３８ダストシール部材
２５２校正ユニット
２５４ユニットハウジング
２７８取付部
２８０標準部材
３０２，３０２Ｂ検知ユニット
３０４，３０４Ｂ，４０４接続ユニット
３２６ファイバ収容部
３２８ロック手段
５０２，５１２，５２２保護管[0001]
BACKGROUND OF THE INVENTION
  The present invention is a dust measurement for measuring the concentration of dust contained in a fluid.EquipmentRelated.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a dust measuring device for measuring the concentration of dust contained in a fluid, a light scattering method using light scattering is known. This type of dust measuring apparatus includes an irradiating means for irradiating measurement light toward a measurement area, a light receiving means for receiving detected light from the measurement area, and the received detected light as required. A dust concentration calculating means for calculating a dust concentration by performing a calculation process on the sensor, and most of the irradiating means and the light receiving means are built in a detector housing inserted into the fluid flow path. In such a dust measuring device, the irradiating means irradiates the measurement light toward the measurement region through the irradiation opening of the detection unit housing, and the light receiving unit receives the detected light from the measurement region through the light reception opening of the detection unit housing. At this time, when the dust in the fluid flowing through the measurement region, that is, dust is large (or small), the irradiated measurement light is scattered by the dust (or less) and the scattered detected light becomes bright (or dark). Thus, the dust concentration in the fluid can be measured based on the scattering rate of the scattered light.
[0003]
[Problems to be solved by the invention]
Such a dust measuring apparatus has the following problems. First, most of the irradiation means and the light receiving means are built in the detection unit housing, but the detection unit housing becomes large in relation to such a configuration, and the dust concentration in the fluid flowing through the small diameter fluid flow path There is a problem that it is difficult to measure. Second, since it is used to measure the concentration of dust flowing in the fluid flow path, the dust in the fluid is liable to cause damage to the members related to the irradiation means and the light receiving means, and hence the irradiation means and the light receiving means. It is desired to realize a dust measuring device that can easily perform maintenance of members related to.
[0004]
In such a dust measurement device, when the detection unit housing is inserted into the fluid flow path or when the detection unit housing is removed from the fluid flow path, a part of the fluid flowing through the fluid flow path flows out to the outside. There is a fear. In particular, when the fluid flowing through the fluid flow path is a high-pressure fluid, fluid leakage is likely to occur.
[0005]
Further, in such a dust measuring device, when detecting the dust concentration, the entire dust measuring device must be carried to a detection place, and the detection work is complicated.
[0006]
Further, in such a dust measuring apparatus, calibration work is periodically performed so that the measurement is accurately performed. In such calibration work, it is necessary to accurately position the standard member in the measurement region. If accurate positioning is not possible, an error occurs in the measurement after calibration.
[0007]
The first object of the present invention is to downsize the configuration related to the irradiating means and the light receiving means, thereby reducing the size of the detecting portion housing, facilitating insertion of the detecting housing, and flowing through a small diameter fluid flow path. It is an object of the present invention to provide a dust measuring device capable of measuring dust concentration in a fluid.
[0008]
A second object of the present invention is to provide a dust measuring device that can reliably prevent fluid leakage when the detector housing is attached or detached.
A third object of the present invention is to provide a dust measuring apparatus capable of measuring the dust concentration with a relatively simple operation.
[0010]
  The present invention includes a detection unit housing having an irradiation opening and a light receiving opening, irradiation means for irradiating measurement light toward the measurement region through the irradiation opening, and light to be detected from the measurement region received through the light receiving opening. A dust measuring device comprising: a light receiving means for performing the above operation; and a dust concentration calculating means for calculating a dust concentration by calculating the detected light received by the light receiving means as required,
  A concave portion is provided at a predetermined portion of the detection unit housing, the irradiation opening is provided on one side of the concave portion, the light receiving opening is provided on the other side, and the irradiation opening and the light receiving opening are in the axial direction of the detection unit housing Facing the
  The irradiating means includes a light emitting source for emitting measuring light and a first optical fiber for guiding the measuring light from the light emitting source to the irradiation aperture, and the light receiving means receives the detected light. And a second optical fiber for guiding the detected light introduced through the light receiving opening to the light receiving element,
  The measurement light from the light source is irradiated through the first optical fiber from the irradiation opening toward the measurement region with an inclination of 10 to 30 degrees with respect to the axial direction of the detection unit housing. The light to be detected is introduced through the light receiving opening inclined by 10 to 30 degrees with respect to the axial direction of the detection unit housing,
  One of the irradiating means and the light receiving means has a reflecting mirror for reflecting light.Including
  Furthermore, the detection unit housing is inserted into the measurement region of the fluid flow path through an insertion path of a seal pipe that communicates with a fluid pipe that defines the fluid flow path, and at one end of the insertion path of the seal pipe, A pair of base side seal members are provided, and at the other end of the insertion path, a pair of tip side seal members are provided, and when inserted into the measurement region of the fluid flow path through the insertion path, The space between the inner peripheral surface and the outer peripheral surface of the detection unit housing is sealed by at least two of the pair of base side seal members and the pair of distal end side seal members.It is characterized by.
[0011]
  According to the present invention, the irradiating means for irradiating the measuring light includes the light source and the first optical fiber, and the light receiving means for receiving the detected light includes the light receiving element and the second optical fiber. Therefore, the measurement light from the light source is irradiated toward the measurement region through the first optical fiber and the irradiation opening, and the detected light is received by the light receiving element through the light receiving opening and the second optical fiber. Since the measurement light is transmitted by the first optical fiber and the detected light is transmitted by the second optical fiber, the outer shape of the detection unit housing can be made small and thin. In addition, an irradiation opening is provided on one side of the concave portion of the detection unit housing, and a light reception opening is provided on the other side. The irradiation opening and the light reception opening are opposed to each other in the axial direction of the detection unit housing. The outer shape of the housing can be effectively reduced. In addition, since one of the irradiating means and the light receiving means includes a reflecting mirror, even when the irradiation opening and the light receiving opening are opposed to each other in the axial direction of the detection unit housing, the first light is transmitted when measuring light or detected light is transmitted. Without bending the optical fiber or the second optical fiber, the measurement light or the detected light can be reflected and transmitted in the opposite direction, thereby further reducing the outer shape of the detection unit housing. The detector housing can be easily inserted into the fluid flow path, and can be inserted into the fluid flow path through a small diameter hole, and the dust concentration in the fluid flowing through the small diameter fluid flow path can be measured. It becomes. Further, the measurement light from the light source is irradiated from the irradiation opening to the measurement region with an inclination of 10 to 30 degrees with respect to the axial direction of the detection unit housing, and the detected light from the measurement region is irradiated to the detection unit housing. Since it is guided to the reflecting mirror with an inclination of 10 to 30 degrees with respect to the axial direction, the outer shape of the detector housing can be reduced, and the irradiation light from the irradiation opening is directly received through the light receiving opening. This can be prevented.In addition, a pair of base side seal members are provided at one end of the insertion path of the seal tube into which the detection unit housing is inserted, and a pair of tip side seal members are provided at the other end side. Since a total of four seal members are provided in a predetermined positional relationship, even if a detection unit housing having a recess is inserted into the fluid flow path through the insertion path, at least two seal members are connected to the inner peripheral surface of the seal tube. It is possible to seal between the outer peripheral surface of the detector housing and thus reliably prevent leakage of the fluid flowing through the fluid flow path through the insertion path.The reflecting mirror is used to transmit light in the opposite direction, and is included in the irradiation means when transmitting the measurement light in the opposite direction, and included in the light receiving means when reflecting the detected light in the opposite direction. It is.
  In addition, the present invention provides a detector housing having an irradiation opening and a light receiving opening, irradiation means for irradiating measurement light toward the measurement region through the irradiation opening, and the light receiving opening for detecting light from the measurement region. A dust measuring device comprising: a light receiving means for receiving light through; and a dust concentration calculating means for calculating a dust concentration by calculating the detected light received by the light receiving means as required,
  A concave portion is provided at a predetermined portion of the detection unit housing, the irradiation opening is provided on one side of the concave portion, the light receiving opening is provided on the other side, and the irradiation opening and the light receiving opening are in the axial direction of the detection unit housing Facing the
  The irradiating means includes a light emitting source for emitting measuring light and a first optical fiber for guiding the measuring light from the light emitting source to the irradiation aperture, and the light receiving means receives the detected light. And a second optical fiber for guiding the detected light introduced through the light receiving opening to the light receiving element,
  The measurement light from the light source is irradiated through the first optical fiber from the irradiation opening toward the measurement region with an inclination of 10 to 30 degrees with respect to the axial direction of the detection unit housing. The light to be detected is introduced through the light receiving opening inclined by 10 to 30 degrees with respect to the axial direction of the detection unit housing,
  One of the irradiation means and the light receiving means includes a reflecting mirror for reflecting light,
  Further, a calibration unit for constituting a measurement value is detachably attached to the detection unit housing, and the calibration unit is used for calibrating the measurement value and a unit housing that is detachably attached to the detection unit housing. A standard member having a standard detection unit and mounted on the mounting portion of the unit housing; and a centering fixing mechanism for positioning and fixing the unit housing in a predetermined positional relationship with the detection unit housing. And
  When the unit housing is mounted on the detection unit housing and centered and fixed by the centering fixing mechanism, the unit housing is positioned and fixed concentrically with respect to the detection unit housing. When mounted on the unit housing, the standard detection part of the standard member is positioned in the measurement region.
  According to the present invention, the configuration relating to the irradiating means, the light receiving means, and the detection housing is substantially the same as that of the dust measuring apparatus described above, so that the same effect is achieved. In addition, the centering fixing mechanism for mounting the unit housing to the detection unit housing positions and fixes the unit housing concentrically with respect to the detection unit housing, and in this state, the standard member is attached to the unit housing. When mounted, the standard detection part of the standard member is positioned in the measurement region, so that the irradiation means irradiates the measurement light toward the standard detection part of the standard member, and the detected light from this standard detection part is applied to the light receiving means. The light is received, and thus the measurement values can be accurately configured using the standard member.
[0012]
  In the present invention, the light receiving means includes the reflecting mirror, and the reflecting mirror is disposed between the light receiving opening and the second optical fiber, and is received through the light receiving opening of the detection unit housing. The detection light is reflected by the reflecting mirror and then received by the light receiving element through the second optical fiber.
  According to the present invention, since the light receiving means includes the reflecting mirror, the detected light introduced through the light receiving opening is reflected to the opposite side by the reflecting mirror and guided to the light receiving element through the second optical fiber. The detector housing can be downsized in relation to the above.
[0014]
In the present invention, the detection unit housing includes first and second housing members that are detachably attached to each other, the irradiation opening is provided in the first housing member, and the light receiving opening is the second light receiving opening. An irradiation port cover is detachably attached to the irradiation opening, a light receiving cover is detachably attached to the light receiving opening, and the reflecting mirror is disposed in the second housing member. It is characterized by being detachably mounted.
[0015]
According to the present invention, the irradiation port cover is detachably attached to the irradiation opening of the detection unit housing, and the light reception port cover is detachably attached to the light reception opening of the detection unit housing. The cover and the light receiving opening cover can be removed, and maintenance and replacement thereof can be easily performed. In addition, the detection unit housing includes first and second housing members that are detachably attached to each other, and a reflecting mirror is detachably attached to the second housing member. By removing the housing member, the reflecting mirror can be removed from the second housing member, and maintenance and replacement of the reflecting mirror can be easily performed.
[0032]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a dust measuring device according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic view showing the whole dust measuring apparatus according to the present invention, FIG. 2 is a partial sectional view showing a part of the dust measuring apparatus of FIG. 1, and FIG. 3 is a dust measuring apparatus of FIG. 4 is a partial cross-sectional view showing the vicinity of the irradiating part and the light receiving part, FIG. 4 is an enlarged partial cross-sectional view showing the light receiving part of the dust measuring apparatus in FIG. 1, and FIG. 5 is a dust measuring apparatus in FIG. FIG. 6 is an exploded cross-sectional view showing a part of the vicinity of the irradiation part and the light-receiving part of FIG. 6, and FIG. 6 is a cross-sectional view showing a state when the detection unit housing of the dust measurement device of FIG. 7 is a partial cross-sectional view showing a state where the detection unit housing is slightly inserted from the state shown in FIG. 6, and FIG. 8 is a partial cross-sectional view showing a state where the detection unit housing is inserted a little from the state shown in FIG. FIG. 9 shows that the detector housing is inserted a little from the state shown in FIG. FIG. 10 is a partial cross-sectional view showing a state in which the detection unit housing is further inserted from the state shown in FIG. 9, and FIG. 11 is a diagram showing a modified example of the detection unit housing. FIG. 12 is a right side view showing a state where the unit housing is attached to the detection unit housing, and FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG.
[0033]
In FIG. 1, the illustrated dust measuring device is used for measuring the concentration of dust 6 such as dust contained in a fluid flowing through a fluid flow path 4 defined by a fluid pipe 2. The dust measuring device includes a cylindrical detection unit housing 8, and the distal end side of the detection unit housing 8 is inserted into the fluid flow path 4 through the insertion tube structure 7. In this embodiment, the insertion tube structure 7 is composed of a ball valve portion 10 and a gas seal portion 12 that are branched from a predetermined portion of the fluid piping 2, and a fluid flow path is provided through the ball valve portion 10 and the gas seal portion 12. 4 is inserted. A gas for fuel as a fluid, for example, high-pressure (for example, 4 MPa) city gas, flows in the fluid flow path 4 in the direction indicated by the arrow, and the dust measuring device determines the dust concentration in the fuel gas flowing in this way. Although it can be used conveniently for measurement, it can also be widely used for measuring the concentration of dust contained in general gases. The ball valve portion 10 and the gas seal portion 12 will be described later.
[0034]
2 and 3, the detection unit housing 8 includes a first housing member 11 on the base side and a second housing member 13 on the tip side, and the first and second housing members 11 and 13 are mutually connected. It is detachably screwed to. An opening is formed in the front end side of the detection unit housing 8, that is, a predetermined portion of the second housing member 13, and a recess 15 is formed by the opening, and the irradiation unit 14 is formed on one side (the base side in this embodiment) of the recess 15. And the light receiving portion 16 is provided on the other side (the tip side in this embodiment). An irradiation opening 18 is provided in the irradiation unit 14 of the detection unit housing 8, and an irradiation port cover 20 is detachably attached to the irradiation opening 18 as described later. The light receiving portion 16 of the detection portion housing 8 is provided with a light receiving opening 22, and a light receiving opening cover 24 is detachably attached to the light receiving opening 22 as will be described later. The irradiation opening cover 20 and the light receiving opening cover 24 are made of a transparent material such as glass, and the irradiation opening 18 and the light receiving opening 22 are sealed by the irradiation opening cover 20 and the light receiving opening cover 24.
[0035]
The dust measuring device includes a measuring device main body 26 separated from the detection unit housing 8. The measuring device main body 26 calculates a light emission source 28 for emitting measurement light, a light receiving element 30 for receiving detected light described later, and detected light received by the light receiving element 30 as required. A dust concentration calculation means 32 for processing is incorporated. The light emission source 28 is composed of, for example, a laser oscillation element, and emits near-infrared laser light. In addition, you may make it use the light emission source which light-emits other light with strong directivity. The light receiving element 30 is constituted by a CCD, for example, and receives light to be detected. The dust concentration calculating means 32 is composed of, for example, a microcomputer, and calculates the concentration of dust contained in the fluid by calculating the light reception signal from the light receiving element 30. There is a predetermined relationship between the amount of dust contained in the fluid and the light to be detected. If the amount of dust is large (or small), the scattering of light by the dust becomes large (or small). The amount of received light increases (or decreases), and the dust concentration calculation means 32 calculates the dust concentration using such a relationship. The measuring device main body 26 is provided with a printing device 34 and a display device 36. The printing device 34 prints the dust concentration calculated by the dust concentration calculating means 32, and the display device 36 calculates the calculated dust concentration. Is displayed.
[0036]
The measuring device body 26 and the detection unit housing 8 are connected by first and second optical fibers 38 and 40. The first optical fiber 38 guides the measurement light from the light source 28 to the irradiation unit 14, and the second optical fiber 40 guides the detected light from the light receiving unit 16 to the light receiving element 30. Since it is configured in this way, the light emission source 28 and the first optical fiber 38 constitute an irradiating means for irradiating the measurement light, and the second optical fiber 40 and the light receiving element 30 receive the detected light. The light receiving means is configured.
[0037]
Referring mainly to FIG. 3, a first closing member 42 is mounted in the detection unit housing 8 on one side of the recess 15 of the detection unit housing 8 (in this embodiment, in the first housing member 11). A fiber holding member 44 is screwed onto the one closing member 42, and the distal end portion of the first optical fiber 38 is positioned and held in the fiber holding member 44. A first concave portion that defines the irradiation opening 18 is provided at the tip of the fiber holding member 44, and the irradiation port cover 20 is attached to the first concave portion. A first cover mounting member 46 is disposed on the surface side of the irradiation port cover 20, and an irradiation is performed by screwing a mounting screw (not shown) to the first closing member 42 through the first cover mounting member 46. The mouth cover 20 is pressed and held by the irradiation opening 18, and thus the irradiation port cover 20 is detachably attached to the first recess of the irradiation unit 14. An opening 48 is provided at the center of the first cover mounting member 46. Thus, the measurement light from the light emission source 28 is projected from the front end surface through the first optical fiber 38, and the space in the fiber holding member 44, the irradiation port cover 20, and the first cover mounting member 46. Irradiated toward the measurement region 50 in the fluid flow path 4 through the opening 48.
[0038]
Further, on the other side of the recess 15 of the detection unit housing 8 (in this embodiment, in the second housing member 13), a second closing member 52 is mounted in the detection unit housing 8 via the light receiving unit holder 51, A condensing lens 54 and a reflecting mirror 56 are attached to the second closing member 52, and the distal end portion of the second optical fiber 40 is supported. A lens support sleeve 58 is screwed to a predetermined portion of the second closing member 52, and a cover holding member 60 is screwed so as to cover one end of the lens support sleeve 58, and one end of the lens support sleeve 58 and the cover holding member are covered. A condensing lens 54 is mounted between the intermediate stage 60 and an O-ring 62. A second recess for defining the light receiving opening 22 is provided at the tip of the cover holding member 60, and the light receiving port cover 24 is attached to the second recess. Similar to the irradiation port cover 20 side, a second cover mounting member 64 is disposed on the surface side of the light receiving port cover 24, and a mounting screw (not shown) is closed through the second cover mounting member 64. By screwing the member 52, the light receiving port cover 24 is pressed and held by the light receiving opening 24, and thus the light receiving port cover 24 is detachably attached to the second concave portion of the light receiving unit 16. An opening 66 is provided at the center of the second cover mounting member 64.
[0039]
Furthermore, a notch 67 is provided at a predetermined portion of the second closing member 52, and a reflecting mirror 56 is attached to the second closing member 52 so that the reflecting surface protrudes into the notch 67. In this embodiment, the reflecting mirror 56 is attached to the mirror supporting member 68, the distal end side of the reflecting mirror 56 is inserted through the insertion hole provided in the second closing member 52, and the mirror supporting member 68 is fixed by the fixing screw 70. 2 By attaching to the back surface of the closing member 52, the reflecting mirror 56 is detachably attached. The second closing member 52 is provided with a fiber insertion hole 72, and the distal end portion of the second optical fiber 40 is inserted and held in the fiber insertion hole 72 and is held via a holding holder 74. The second closing member 52 is attached to the light receiving part holder 51, and the light receiving part holder 51 is detachably attached to the second housing member 13 by an attaching screw 71. A spacer 73 is interposed between the light receiving unit holder 51 and the second closing member 52. A cover sleeve 76 is attached between the first closing member 42 and the second closing member 52, and the second optical fiber 40 extends to the second closing member 52 through the cover sleeve 76.
[0040]
Thus, the light to be detected from the measurement region 50 passes through the opening 66 of the second cover mounting member 64, the light receiving port cover 24, the internal space of the cover holding member 60, the condensing lens 54, and the lens support sleeve 58. After reaching the reflecting mirror 56 through the internal space, the hole 77 of the second closing member 52 and the notch 67 and reflected by the reflecting surface of the reflecting mirror 56, the light is received by the tip surface of the second optical fiber 40 through the notch 67. The light to be detected thus received is guided to the light receiving element 30 through the second optical fiber 40. Since the detected light is received in this way, the condenser lens 54 and the reflecting mirror 56 also constitute part of the light receiving means.
[0041]
  In this embodiment,As is apparent from FIGS. 2 and 3, the irradiation opening 18 and the light receiving opening 22 face each other in the axial direction of the detector housing 78.The distal end portion of the first optical fiber 38 is held at an appropriate angle of 10 to 30 degrees, for example, about 20 degrees with respect to the axial direction of the detection section housing 8 (left and right direction in FIGS. 2 and 3). Accordingly, the measurement light from the first optical fiber 38 is irradiated at an angle inclined by, for example, about 20 degrees with respect to the axial direction. The optical axis passing through the condenser lens 54 is inclined at an appropriate angle of 10 to 30 degrees, for example, about 20 degrees with respect to the axial direction of the detection unit housing 8, and the tip of the second optical fiber 40 is the detection unit. The light to be detected that extends in the axial direction of the housing 8 and is scattered in the optical axis direction from the measurement region 50 is reflected by the reflecting surface of the reflecting mirror 56 in the axial direction of the detection unit housing 8. Guided to the second optical fiber 40. In this way, the measurement light from the irradiation unit 14 directly enters the light receiving unit 16 by inclining the irradiation angle from the irradiation unit 14 and the optical axis angle of the light receiving unit 16 with respect to the axis of the detection unit housing 8 by a predetermined angle. Only the detected light from the measurement region 50 is received by the light receiving unit 16 without being received, whereby the dust concentration in the fluid can be accurately measured. Further, since the detected light received by the light receiving unit 16 is reflected by the reflecting mirror 56, the detected light can be guided in an opposite direction at an acute angle to reach the distal end surface of the second optical fiber 40. As a result, the outer shape of the detection unit housing 8 can be reduced, and the reduction in size and weight can be achieved. In this embodiment, a light shielding plate 80 that protrudes outward is provided at the central portion in the axial direction of the recess 15 of the detection unit housing 8. The light shielding plate 80 reliably prevents the measurement light emitted from the irradiation unit 14 from being directly received by the light receiving unit 16.
[0042]
The dust measuring apparatus further includes a purge for preventing dust from adhering to the irradiation surface of the irradiation unit 14 (the surface of the irradiation port cover 20) and the light receiving surface of the light receiving unit 16 (the surface of the light reception port cover 24). A mechanism is provided. The illustrated purge mechanism is configured to prevent the dust, mist, and the like from adhering to the irradiation surface of the irradiation unit 14 and the dust, mist, and the like from adhering to the light receiving surface of the light receiving unit 16. Second purge fluid feeding means 84 for preventing, the first purge fluid feeding means 82 includes a first purge fluid feeding flow path 86, and the second purge fluid feeding means 84 is a second purge. A fluid feed channel 88 is provided. In this embodiment, the first and second purge fluid feed channels 86, 88 are joined to the main purge fluid feed channel 90, and the main purge fluid feed channel 90 is connected to the purge fluid supply source 92. ing. The purge fluid supply source 92 is composed of, for example, a fluid tank. The fluid tank is filled with a fluid having substantially the same component as the fluid flowing through the fluid flow path 4, and the purge fluid thus filled is purged as described later. . When a fuel gas, for example, city gas, flows through the fluid flow path 4, a purge gas of substantially the same component, for example, city gas, is purged from the purge fluid supply source 92. By purging in this way, the purge fluid Even if is added, the component of the fluid flowing through the fluid flow path 4 does not change, and the amount of combustion heat of the fuel gas flowing through the fluid flow path 4 can be kept constant.
[0043]
In this embodiment, the main purge fluid supply channel 90 is attached to the first block member 42, the annular channel 96 formed in the first blocking member 42, the channel 98 extending from the annular channel 96, and the first blocking member 42. The flow path 102 of the connecting member 100, the flow path 106 formed in the end member 104 of the detection unit housing 8, and the flow path of the connection pipe 112 disposed between the end member 104 and the connection member 110. 114, and the flow path 106 of the end member 104 is connected to the purge fluid supply source 92 via the flow path 118 of the tube member 116.
[0044]
The first purge fluid supply channel 86 includes a channel 120 formed in the first closing member 42, and the channel 120 extends from the annular channel 96 to the first cover mounting member 46. The second purge flow path 88 includes a flow path 122 extending from the annular flow path 96 of the first closing member 42, a flow path 126 of the short connection member 124 attached to the first closing member 42, and a second closing member. 52, the flow path 130 of the short connection member 128, the flow path 134 of the connection pipe 132 disposed between the short connection members 124, 128, the flow path 136 of the second closing member 52, and the annular flow thereof. A passage 138 and a passage 140 extending from the annular passage 138 to the second cover mounting member 64 are included. With this configuration, the purge fluid from the purge fluid supply source 92 flows into the annular flow channel 96 of the first closing member 42 through the main purge fluid supply flow channel 90, and from the annular flow channel 96 to the first flow channel It flows toward the first cover mounting member 46 through the purge fluid supply flow path 86 and flows toward the second cover mounting member 64 through the second purge fluid supply flow path 88.
[0045]
In this embodiment, a check valve 146 is disposed in the main purge fluid supply passage 90. The check valve 146 includes a spherical valve body 148, a pressing member 150 that presses the valve body 148, and a coil spring 152 that acts on the pressing member 150, and the coil spring 152 is interposed via the pressing member 150. The valve body 148 is elastically biased in the closing direction (leftward in FIG. 2). By providing the check valve 146 in this manner, the backflow of the fluid through the main purge fluid supply channel 90 is prevented, and the fluid flowing through the fluid channel 4 is allowed to flow through the first purge fluid supply channel 86 and / or the first purge fluid supply channel 86. 2 Backflow to the purge fluid supply source 92 side through the purge fluid supply flow path 88 is prevented. In the illustrated embodiment, a shaft portion 151 is provided on one side of the pressing member 150 (the side opposite to the surface acting on the valve body 148), and a coil spring 152 is mounted so as to fit the shaft portion. Therefore, the biasing force of the coil spring 152 acts stably on the valve body 148 via the pressing member 150, and thus the backflow of the fluid through the main purge fluid supply channel 90 can be more reliably prevented. When there is a sufficient installation space in the first and second purge fluid supply passages 86 and 88, such a check valve is provided in the first and second purge fluid supply passages 86 and 88. It may be.
[0046]
The purge fluid flowing through the first and second purge fluid supply channels 86 and 88 is ejected toward the irradiation surface of the irradiation port cover 20 and the light reception surface of the light reception port cover 24 as follows. The first and second cover mounting members 46 and 64 have substantially the same configuration. Hereinafter, mainly with reference to FIG. 4, the second cover mounting member 64 (first cover mounting member 46) and the related configuration will be described. explain.
[0047]
The second cover mounting member 64 (first cover mounting member 46) attached to the light receiving surface (irradiation surface) side of the light receiving port cover 24 (irradiation port cover 20) is formed from the outer peripheral wall 162 and the tip of the outer peripheral wall 162. An inner peripheral wall 164 extending inward in the radial direction toward the light receiving surface (irradiation surface), and the outer peripheral wall 162 is mounted so as to abut against the second closing member 52 (first closing member 42). . In this mounted state, the tip of the inner peripheral wall 164 presses the light receiving surface (irradiation surface) of the light receiving port cover 24 (irradiation port cover 20), and the light receiving port cover 24 (irradiation port cover 20) is 2 pressed and held in the recess (the first recess of the irradiation unit 14).
[0048]
A second annular space 166 (first annular space) is defined between the outer peripheral wall 162 and the inner peripheral wall 164 of the second cover attaching member 64 (first cover attaching member 46), and the second annular space 166 ( The first annular space) communicates with the second purge fluid supply channel 88 (first purge fluid supply channel 86). A plurality of jet outlets 170 are provided at the distal end of the inner peripheral wall 164 at intervals in the circumferential direction. In this embodiment, the ejection port 170 is formed in a rectangular shape, but may be formed in an appropriate shape such as a semicircular shape.
[0049]
Since it is configured in this way, the purge fluid from the second purge fluid supply flow path 88 (first purge fluid supply flow path 86) is transferred to the second cover mounting member 64 (first cover mounting member 46). The light receiving port cover 24 (irradiation port cover 20) flows into the second annular space 166 (first annular space) and radially inward from the plurality of jets 170 through the second annular space 166 (first annular space). It is ejected along the light receiving surface (irradiated surface).
[0050]
In this embodiment, in addition, in order to reliably prevent the fluid flowing through the fluid flow path 4 from flowing into the detection unit housing 8, a double seal structure using double O-rings 180 is provided where necessary. It has been adopted. That is, as shown in FIGS. 2 and 3, this double seal structure includes the mounting portion of the first closing member 42, the mounting portion of the second closing member 52, the mounting portion of the fiber holding member 44, the short connection member 124, It is used for 128 mounting parts, a mounting part for holding holder 76, a mounting part for cover holding member 60, and the like.
[0051]
In the dust measuring apparatus described above, the purge fluid from the purge fluid supply source 92 is fed to the first and second purge fluid feed channels 86 and 88 through the main purge fluid feed channel 90, and the first purge fluid feed is sent. The purge fluid supplied to the supply channel 86 is ejected from the ejection port of the first cover mounting member 46 toward the irradiation surface of the irradiation port cover 20 and is also fed to the second purge fluid supply channel 88. The purge fluid thus made is ejected from the ejection port 170 of the second cover mounting member 64 toward the light receiving surface of the light receiving port cover 24. Accordingly, dust, mist, etc. near the irradiation surface is blown away by the purge fluid that flows radially inward from the outlet of the first cover mounting member 46 and then flows away from the irradiation surface, and dust, mist near the light receiving surface, The mist is blown off by the purge fluid that flows radially inward from the jet outlet 170 of the second cover mounting member 64 and then flows away from the light receiving surface, and thus dust, mist, and the like adhere to the irradiation surface and the light receiving surface. Even if dust, mist or the like adheres to these surfaces, it can be blown away.
[0052]
In this dust measuring apparatus, the irradiation port cover 20, the light receiving port cover 24, and the reflecting mirror 56 can be maintained and replaced as follows. Referring mainly to FIGS. 3 and 5, with respect to the irradiation port cover 20, the first cover mounting member 46 can be removed from the detector housing 8 by removing a mounting screw (not shown). 5, the irradiation port cover 20 can be removed from the first recess of the irradiation unit 14, and thus maintenance (for example, cleaning of the irradiation surface) and replacement of the irradiation port cover 20 can be easily performed. it can.
[0053]
As for the light receiving port cover 24, similarly to the irradiation port cover 20, the second cover mounting member 64 can be removed from the detection unit housing 8 by removing a mounting screw (not shown). As shown in FIG. 4, the light receiving port cover 24 can be removed from the second recess of the light receiving unit 16, and thus the light receiving port cover 24 can be easily maintained (for example, cleaning of the irradiation surface) and replaced. .
[0054]
Further, when the first and second housing members 11 and 13 of the detection unit housing 8 are unscrewed, as shown in FIG. 5, the light receiving unit holder 51, the second closing member 52, and the lens support together with the second housing member 13. The sleeve 58, the cover holding member 60, the condenser lens 54, the light receiving opening cover 24, the second cover mounting member 64, the mirror support member 68 and the reflecting mirror 56 are separated from the first housing member 11 side. Can be removed from the side. Then, when the mounting screw 71 is loosened in the removed state, the light receiving unit holder 51 and various members incorporated therein from the second housing member 13 side (the light receiving port cover 24, the reflecting mirror 56, and members related thereto). Can be separated from the second housing member 13 and removed from the second housing member 13 side. In this state, when the fixing screw 70 is removed after the light receiving unit holder 51 covering the second closing member 52 is removed, the mirror support member 68 and the reflecting mirror 56 attached thereto are removed from the second closing member 52. Thus, the mirror 56 can be easily removed for maintenance, replacement, and the like.
[0055]
Next, the insertion tube structure 7 (the ball valve portion 10 and the gas seal portion 12 (which constitutes a seal tube)) and a configuration related thereto will be described with reference to FIGS. A connecting member 202 is connected to the fluid piping 2, the ball valve portion 10 is connected to the connecting member 202, and the gas seal portion 12 is connected to the ball valve portion 10. The connecting member 202 is composed of a tubular member, and an arcuate portion 204 at one end thereof is, for example, fused to the outer peripheral surface of the pipe 2. A connection flange 206 is provided at the other end of the connection member 202. The ball valve unit 10 has a valve housing 210 having a flow path 208, and a ball valve 212 is disposed in the flow path 208 of the valve housing 210. The ball valve 212 is provided with a through hole 214. Further, a shaft member 216 is fixed to the ball valve 212, the shaft member 216 protrudes from the valve housing 210, and an operation handle 218 is attached to the protruding end portion of the shaft member 216. A connection flange 220 is provided at one end of the valve housing 210, and the connection member 202 and the connection flanges 206 and 220 of the valve housing 210 are connected to each other by a bolt 222 and a nut 224.
[0056]
Further, the gas seal portion 12 includes a seal housing 226, an insertion path 228 is provided in the seal housing 226, and the insertion path 228 communicates with the flow path 208 of the valve housing 210. A connection flange 230 is provided at one end of the seal housing 226, and a connection flange 232 is also provided at the other end of the valve housing 210. These connection flanges 230 and 231 are connected to each other by bolts 222 and nuts 224. Yes.
[0057]
In this embodiment, a pair of base-side seal members 232 are disposed at one end portion (right end portion in FIG. 6) of the insertion path 228 of the seal housing 226, and the other end portion ( A pair of front end side seal members 234 are disposed at a distance from the left end portion in FIG. These seal members 232 and 234 are composed of, for example, rubber O-rings and the like, and prevent the fluid flowing through the fluid flow path 4 from leaking to the outside.
[0058]
A first dust seal member 236 is disposed on the outside (right side in FIG. 6) of the pair of base side seal members 232 of the insertion path 228, and on the outside (left side in FIG. 6) of the pair of distal end side seal members 234. Two dust seals 238 are provided. The first dust seal member 234 prevents dust contained in the fluid flowing through the fluid flow path 4 from entering the base side seal member 232, and the second dust seal member 238 is configured to prevent external dust from being sealed on the front end side. Intrusion into the member 234 is prevented. By providing the first and second dust seal members 236 and 238 in this way, dust is applied to the base side and distal end side seal members 232 and 234 in a state where the detection unit housing 8 is inserted into the fluid flow path 4 as described later. Can be prevented from entering, the scratches of the seal members 232 and 234 can be prevented, and a desired sealing effect can be maintained over a long period of time.
[0059]
Next, an operation of inserting the detector housing 8 into the fluid flow path 4 when measuring the dust concentration in the fluid flowing through the fluid flow path 4 will be described. In a state where the ball valve portion 10 is held in a closed state (a state where the ball valve 212 closes the flow path 208), first, the tip of the detection portion housing 8 is inserted into the gas seal portion 12 as shown in FIG. Insert into path 228. In this inserted state, the concave portion 15 of the detection unit housing 8 is located at a position where the pair of distal end side seal members 234 are arranged. At this time, the cylindrical portion of the second housing member 13 of the detection unit housing 8 is a pair of base portions. Therefore, the gap between the outer peripheral surface of the detection unit housing 8 and the inner peripheral surface of the seal housing 226 is sealed by the two seal members of the pair of base side seal members 232.
[0060]
Next, the operation handle 218 is operated to open the ball valve unit 10, and the through hole 214 of the ball valve 212 is communicated with the flow path 208 of the valve housing 210. When the detection unit housing 8 is inserted in the insertion direction indicated by the arrow in this state, as shown in FIG. 7, the recess 15 of the detection unit housing 8 becomes a pair of base side seal members 232 and a pair of tip side seal members 234. Correspondingly, the cylindrical portion of the second housing member 13 of the detection unit housing 8 is positioned on the pair of base-side seal members 232 and the first housing member 11 The cylindrical portions are positioned on the pair of distal end side seal members 234, and therefore, between the outer peripheral surface of the detection unit housing 8 and the inner peripheral surface of the seal housing 226, the pair of base side seal members 232 and the pair of distal end side seals. Sealed by the four sealing members of the member 234.
[0061]
When the detection unit housing 8 is further inserted in the insertion direction indicated by the arrow from this state, the recess 15 of the detection unit housing 8 comes to be positioned on the inner base side seal member 232 as shown in FIG. The cylindrical portion of the second housing member 13 of the detection unit housing 8 is positioned on the outer base side seal member 232, and the cylindrical portion of the first housing member 11 is positioned on the pair of distal end side seal members 234, Accordingly, the space between the outer peripheral surface of the detection unit housing 8 and the inner peripheral surface of the seal housing 226 is sealed by the three seal members of the outer base side seal member 232 and the pair of distal end side seal members 234.
[0062]
When the detection unit housing 8 is further inserted in the direction indicated by the arrow from this state, the recess 15 of the detection unit housing 8 is positioned inside the pair of base side seal members 232 as shown in FIG. The cylindrical portion of the first housing member 11 of the detection unit housing 8 is positioned on the pair of distal end side seal members 234, and therefore, there is a pair between the outer peripheral surface of the detection unit housing 11 and the inner peripheral surface of the seal housing 226. The two sealing members of the front end side sealing member 234 are sealed.
[0063]
Thereafter, when the detection unit housing 8 is further inserted in the insertion direction indicated by the arrow, the recess 15 of the detection unit housing 8 is positioned inside the pair of base side seal members 232 as shown in FIG. The cylindrical portion of the first housing member 11 of the detection unit housing 8 is located on the pair of base side seal members 232 and the pair of tip side seal members 234, and accordingly, the outer peripheral surface of the detection unit housing 8 and the inside of the seal housing 226 The gap between the peripheral surface and the peripheral surface is sealed by four seal members, ie, a pair of base-side seal members 232 and a pair of distal-end-side seal members 234, and inserted into a predetermined position in the direction of the arrow while maintaining this sealed state.
[0064]
In this embodiment, the front end of the detection unit housing 8 is a predetermined passage of the fluid flow path 4 through the insertion path 228 of the seal housing 226, the flow path 208 of the valve housing 210, the through hole 214 of the ball valve 212, and the space in the connection member 202. Inserted to the site. At the time of this insertion, as described above, at least two of the pair of base side seal members 232 and the pair of distal end side seal members 234 provide a gap between the detection unit housing 8 and the seal housing 226. Even if a high pressure fluid is flowing through the fluid flow path, the leakage can be reliably prevented.
[0065]
In such a dust measuring apparatus, it is desirable to calibrate the measured value with the following configuration. In addition, in the detection part housing of this modification, the same reference number is attached | subjected and demonstrated to the member substantially the same as embodiment shown in FIGS.
[0066]
11 to 13, when the measurement value is calibrated, the calibration unit 252 is attached to the distal end portion of the detection unit housing 8 as shown in FIG. 11. The illustrated calibration unit 252 includes a hollow cylindrical unit housing 254, and end walls 256 and 258 are provided at both ends thereof. On the other hand, a first opening 260 is provided at the center of the end wall 256, and second openings 264 (only one is shown in FIG. 13) are provided on both sides of the first opening 260. The opening of the second opening 264 is tapered. A tapered portion 266 extending in a shape is provided (see FIG. 13). The other end wall 258 is provided with an insertion opening 268 corresponding to the outer diameter of the detector housing 8.
[0067]
A pair of screw shafts 270 (see FIG. 12) is fixed to the light receiving unit holder 51 of the detection unit housing 8. A pair of openings 273 are provided in the end wall 272 of the second housing member 13, and each screw shaft 270 protrudes outward through the corresponding opening 273.
[0068]
The unit housing 254 is attached to the detector housing 8 as follows. That is, the detection unit housing 8 is inserted through the insertion opening 268 of the end wall 258 of the unit housing 254, and the pair of screw shafts 270 protruding from the second housing member 13 is inserted through the second opening 264 of the end wall 256, and thereafter Then, the tightening screw 271 is screwed onto the projecting end portion of the screw shaft 270 projecting from the end wall 256 of the unit housing 254 and tightened. When tightened in this way, the end wall 256 of the unit housing 254 contacts the end wall 272 of the detector housing 8, thereby positioning the unit housing 254 in the axial direction (left-right direction in FIG. 11). Further, on the other end side of the unit housing 254, the end wall 258 is fitted on the detection unit housing 8, and thereby is positioned concentrically with respect to the detection unit housing 8. Further, on one end side of the unit housing 254, the taper portion 274 provided on the fastening screw 271 corresponding to the taper portion 266 of the second opening 264 fits into the taper portion 266 of the corresponding second opening 264. Thus, the head portion of the mounting screw 71 is positioned in the first opening 260 of the end wall 256 of the unit housing 254 in the state where it is positioned concentrically with respect to the detector housing 8 and mounted in this manner. To do. Since the positioning and fixing are performed in this way, the screw shaft 270 and the tightening screw 271 constitute a centering fixing mechanism, and the center housing fixing mechanism accurately positions and fixes the unit housing 254 to the tip of the detection unit housing 8. Can do.
[0069]
An attachment portion 278 is provided at a predetermined portion of the unit housing 254, and the standard member 280 is attached to the attachment portion 278. In this embodiment, the mounting portion 278 is constituted by a hollow cylindrical guide mounting member 282, and the guide mounting member 282 is fixed to the side surface of the unit housing 254, and the guide mounting member 282 has a guide extending in the axial direction on the inner peripheral surface. A groove 283 is provided. A rectangular insertion hole 284 is formed on the side surface of the unit housing 254 corresponding to the guide mounting member 282. On the other hand, the standard member 280 has a cylindrical main body portion 286 and a standard detection portion 288 provided at the tip of the main body portion 286, and the plate-like standard detection portion 288 has a measurement value calibrated. The dust pattern that is the standard of is given. A guided projection 290 is provided on the peripheral surface of the main body 286.
[0070]
The standard member 280 is attached by being inserted into the guide attachment member 282. At this time, the guided protrusion 290 of the main body 286 is inserted into the guide groove 283 of the guide attachment member 282 and guided along the guide groove 283. When mounted in this manner, the front end surface of the main body 286 contacts the outer peripheral surface of the unit housing 254, whereby the standard member 280 is positioned in the insertion direction, and the standard detection unit 288 passes through the insertion hole 284 of the unit housing 254. Projected into 254 and positioned in measurement area 50. Further, since the guided projection 290 is positioned in the guide groove 283, the relative angle of the standard member 280 with respect to the unit housing 254 (that is, the detection unit housing 8) is determined. Therefore, after the unit housing 254 is mounted on the front end of the detection unit housing 8 as described above, the standard member 280 is attached as described above, whereby the standard detection unit 288 of the standard member 280 is attached to the detection unit housing 8. It is possible to accurately position in a predetermined positional relationship, that is, in a predetermined measurement region 50. As a result, the measurement value using the standard member 280 can be calibrated accurately.
[0071]
Next, another embodiment of the dust measuring device will be described with reference to FIGS. FIG. 14 is a cross-sectional view showing a state in which the detection unit of the dust measurement device of another embodiment is housed, and FIG. 15 shows the state before connecting the connection unit to the detection unit of the dust measurement device of FIG. FIG. 16 is a cross-sectional view, and FIG. 16 is a cross-sectional view showing a state in which a connection unit is connected to the detection unit of the dust measuring device of FIG. In the following embodiments, the same reference numerals are given to substantially the same components as those shown in FIGS. 1 to 10, and the description thereof is omitted.
[0072]
Referring to FIGS. 14 to 16, the dust measuring apparatus according to another embodiment includes a detection unit 302 and a connection unit 304 that is detachably connected to a rear end portion of the detection unit 302. The detection unit 302 includes a detection unit housing 306. The irradiation unit 14 is provided on one end side of a recess 308 provided at the tip of the detection unit housing 306, and the light receiving unit 16 is provided on the other end side. An annular recess 310 is provided at the rear of the detection unit housing 306. The other configuration of the detection unit 302 is substantially the same as the detection unit housing 8 and the related configuration in the embodiment shown in FIGS.
[0073]
The connection unit 304 includes a connection portion housing 312, has a connection protrusion 314 at the front end thereof, and a rear end member 316 is attached to the rear end thereof. As shown in FIG. 16, the connection portion housing 312 has a space through which the first optical fiber 38A and the second optical fiber 40A are inserted, and is connected to a purge flow path in the detection portion housing 306. The purge channel narrow tube 318 is built in, and the purge channel narrow tube 318 is connected to a purge fluid supply source (not shown) for supplying the purge fluid.
[0074]
An annular recess 320 is provided at a substantially central portion in the axial direction of the connection portion housing 312. Corresponding to the annular recess 320, a support member 322 is mounted in the connection portion housing 312. The support member 322 is provided with insertion holes for inserting the first and second optical fibers 38A and 40A. In addition, the end portion of the purge flow path narrow tube 318 is supported. Further, a push handle 324 is provided at the rear end of the connection portion housing 312. Furthermore, the rear end member 316 is provided with a lead-out hole for leading out the first and second optical fibers 38A and 40A.
[0075]
The detection unit 302 and the connection unit 304 are inserted through the insertion pipe structure 7A connected to the fluid pipe 2. The basic structure of the insertion tube structure 7A in the illustrated embodiment is substantially the same as that shown in FIG. 6, but a fiber is attached to the end (rear end) of the seal housing 226 of the gas seal portion 12A (seal tube). An accommodating portion 326 is provided, and a lock means 328 is provided on the seal housing 226, and the lock means 328 includes a lock screw 330 that is screwed onto the seal housing 226.
[0076]
In this embodiment, the base side of the first and second optical fibers 38A, 40A is configured to be connected to a light emitting source and a light receiving element (not shown) through the connection unit 304, and in this regard, A part of the first and second optical fibers 38A, 40A extending from the rear end side (base side) of the detection unit 302 is accommodated in the fiber accommodating portion 326. When the dust concentration is not measured, as shown in FIG. 14, the detection unit 302 is accommodated and held in the insertion tube structure 7A, that is, in the connection member 202, the ball valve portion 10 and the gas seal portion 12, and the tip of the lock screw 330 is When the portion engages with the annular recess 310 of the detection portion housing 306, it is locked and held in this accommodated state. In this accommodated state, the tip of the detection unit 302 does not protrude into the flow path pipe 2 and does not become a resistance of the fluid flowing through the fluid flow path 4.
[0077]
In this accommodated state, a part of the first and second optical fibers 38A, 40A extending from the detection unit 302 is accommodated in a ring shape in the fiber accommodating portion 326, and, for example, as required by the breakage prevention holding piece 332 It is stored by winding it in a ring shape. One end of the fiber accommodating portion 326 is sealed by a plate-like lid member 334, and by sealing in this way, leakage of the fluid flowing through the fluid flow path 4 to the outside through the insertion tube structure 7A is surely prevented. can do.
[0078]
Next, dust measurement by this dust measuring device will be described. When measuring the dust concentration, as shown in FIG. 15, the lid member 334 is removed to open the fiber accommodating portion 326 and accommodate in the fiber accommodating portion 326. Part of the first and second optical fibers 38A and 40A thus taken out are taken out. At this time, when the breakage prevention holding pieces 332 get in the way, some of them are removed, but the breakage prevention holding pieces 322 are detachably attached to the fiber accommodating portion 326 (not shown). If it is attached to the above, the holder can be removed.
[0079]
Next, the first and second optical fibers 38A and 40A are passed through the connection portion housing 312 from one end (connection protrusion 314) side to the other end (rear end member 316) side of the connection unit 304, and in this inserted state, The push handle 316 of the connection unit 304 is pressed in the insertion direction indicated by the arrow 340 and the distal end side thereof is inserted into the insertion tube structure 7A (gas seal portion 12A), and the distal end portion of the connection unit 304 is connected to the rear end portion of the detection unit 302. Removably connect. For such connection, for example, a connection groove is provided at the rear end of the detection unit housing 306, and a connection pin is provided at the tip of the connection unit housing 312, and the connection pin is engaged with the connection groove. Can be done. With this connection, the purge thin tube 318 of the connection unit 304 is connected to the purge flow path (not shown) of the detection unit 302.
[0080]
Thereafter, the lock screw 330 is loosened to release the lock state by the lock means 328, the push handle 324 is further pushed in the direction indicated by the arrow 340, and the detection unit 302 and the connection unit 304 are inserted. As shown in FIG. When the irradiation unit 14 and the light receiving unit 16 of 302 are inserted until they reach a predetermined measurement region of the fluid flow path 4, the lock screw 330 is tightened to engage the tip of the lock screw 330 with the annular recess 320 of the connection unit 306. As a result, the lock means 328 is locked, and the detection unit 302 and the connection unit 304 are locked and held in the state shown in FIG. Thereafter, the end portions of the first and second optical fibers 38A and 40A extending through the connection unit 304 are connected to a light emitting source (not shown) and a light receiving element (not shown), and thus the measurement preparation work is performed. And after this preparatory work, the dust concentration in the fluid flowing through the fluid flow path 4 can be measured as described above.
[0081]
After the dust concentration is finished, the lock screw 330 is loosened in the opposite manner as described above. Thus, the detection unit 302 and the connection unit 304 are pushed outward by the pressure of the fluid flowing through the fluid flow path 4. Then, when pushed out to a predetermined position, the lock screw 330 is tightened, and its tip is engaged with the annular recess 310 of the detection unit 302, and the detection unit 302 is locked and held in the insertion tube structure 7A. Next, the connection unit 304 is removed from the detection unit 302, and the first and second optical fibers 38A and 40A are removed from the connection unit 326 and accommodated in the fiber accommodating portion 326, and then the opening of the fiber accommodating portion 326 is covered with a lid. A member 334 is attached. In this way, as shown in FIG. 14, the detection unit 302 is accommodated in the insertion tube structure 7A, and part of the first and second optical fibers 38A, 40A is accommodated in the fiber accommodating portion 326. It is stored in a state of being attached to a predetermined part.
[0082]
In this embodiment, one connection unit 304 is connected, but a plurality of connection units 304 may be connected. In this case, one or two or more intermediate connection units (not shown) are connected between the detection unit 302 and the connection unit 304, and the structure of the front end side of each intermediate unit is the front end of the connection unit 304 described above. The structure on the rear end side may be substantially the same as the structure on the side, and the structure on the rear end side of the detection unit 302 described above may be substantially the same.
[0083]
Next, still another embodiment of the dust measuring device will be described with reference to FIGS. FIG. 17 is a cross-sectional view showing a state in which the detection unit of the dust measurement device of still another embodiment is housed, and FIG. 18 shows a state before the connection unit is connected to the detection unit of the dust measurement device of FIG. FIG. 19 is a partial cross-sectional view showing a connection portion between the detection unit and the connection unit of the dust measurement device in FIG. 17, and FIG. 20 shows a connection unit in the detection unit of the dust measurement device in FIG. It is sectional drawing which shows the state connected.
[0084]
Referring to FIGS. 17 to 20, the dust measuring apparatus according to still another embodiment includes a detection unit 302 </ b> B, an intermediate connection unit 304 </ b> B that is detachably connected to the rear end portion of the detection unit 302 </ b> B, and the intermediate unit And a rear connection unit 404 that is detachably attached to the rear end of the connection unit 304B. The first and second optical fibers 38B and 40B are built in the detection unit 302B, the intermediate connection unit 304B, and the rear connection unit 404. ing.
[0085]
The detection unit 302B includes a detection unit housing 306B. The irradiation unit 14 is provided on one end side of the recess 308 provided at the tip of the detection unit housing 306B, and the light receiving unit 16 is provided on the other end side. The detection unit 302B includes an irradiation-side first fiber member 352 of the first optical fiber 38B and a light-receiving side first optical fiber member 354 of the second optical fiber 40B. One end portion of the irradiation-side first fiber member 352 extends to the irradiation portion 14, the other end portion extends to the rear end portion of the detection portion housing 306B, and a connection member 356 is provided at the other end portion. In addition, one end portion of the light receiving side first fiber member 354 extends to the vicinity of the light receiving portion 16, the other end portion extends to the rear end portion of the detecting portion housing 306 </ b> B, and a connecting member 358 is provided at the other end portion. Further, an annular recess 310 is provided at the rear of the detection unit housing 306B. The other configuration of the detection unit 302B is substantially the same as the detection unit housing 8 and the related configuration in the embodiment shown in FIGS.
[0086]
The intermediate connection unit 304B includes a connection portion housing 312B, has a connection protrusion 314 at the front end thereof, and a rear end member 316 is attached to the rear end thereof. The connection unit 304B includes an irradiation side second fiber member 360 of the first optical fiber 38B and a light reception side second optical fiber member 362 of the second optical fiber 40B. One end portions of the irradiation-side and light-receiving-side second fiber members 360 and 362 extend to the connection protrusions 314 of the connection portion housing 312B, and connection members 364 and 366 are provided at one end portions thereof, and the other end portions thereof. Extends to the rear end portion of the connection portion housing 312B, and connection members 368 and 370 are provided at the other end portions thereof. Further, an annular recess 320 is provided at the rear part of the connection housing 312B. The other configuration of the intermediate connection unit 304B is substantially the same as the configuration of the connection unit 304 in the embodiment shown in FIGS.
[0087]
The rear connection unit 404 includes a connection portion housing 412, has a connection protrusion 414 at the front end thereof, and a rear end member 416 is attached to the rear end thereof. Thereafter, the connection unit 404 includes an irradiation-side third fiber member 372 of the first optical fiber 38B and a light-receiving-side third optical fiber member 374 of the second optical fiber 40B. One end portions of the irradiation side and light receiving side third fiber members 372 and 374 extend to the connection protrusions 414 of the connection portion housing 412, and connection members 376 and 378 are provided at one end portions thereof, and the other end portions thereof. Extends outward through the rear end member 416, and connecting members 380 and 382 are provided at the other end thereof. Further, the rear end member 416 is provided with a push handle 386 for pushing the rear connection unit 404 in the insertion direction indicated by an arrow 384. The other configuration of the subsequent connection unit 404 is substantially the same as that of the intermediate connection unit 304B.
[0088]
The detection unit 302B, the intermediate connection unit 304B, and the rear connection unit 404 are inserted through the insertion pipe structure 7B connected to the fluid pipe 2. The basic structure of the insertion tube structure 7B in the illustrated embodiment is substantially the same as that shown in FIGS. 14 to 17, and the gas seal portion 12B is provided with a lock screw 330 constituting the lock means 328. Instead of providing the accommodating portion, a flange 388 is provided at an end portion (rear end portion) of the seal housing 226 of the gas seal portion 12B (seal pipe), and a closing member 394 is provided on the flange 388 by a bolt 390 and a nut 392. Sealed on.
[0089]
Next, dust measurement by this dust measuring device will be described. When measuring the dust concentration, as shown in FIG. 18, the lid member 394 is removed to open the insertion side of the insertion tube structure 7B, and the intermediate connection unit. The front end side of 304B is inserted into the insertion tube structure 7B and connected to the rear end portion of the detection unit 302B held therein, and the front end portion of the rear connection unit 404 is connected to the rear end portion of the intermediate connection unit 304B. . When the connection protrusion 314 of the intermediate connection unit 304B is inserted and connected to the rear end of the detection unit 302B, the connection members 364 and 366 on the intermediate connection unit 304B side are connected to the detection unit 302B side as understood from FIG. It is received in the connection members 356 and 358, whereby the irradiation-side and light-receiving-side second fiber members 360 and 362 on the intermediate connection unit 304B side, and the irradiation-side and light-receiving-side first fiber members 352 on the detection unit 302B side. , 354 are connected to each other. Further, the purge flow path 397 on the detection unit 302B side in which the check valve 396 is incorporated is connected to the purge thin tube 398 incorporated in the intermediate connection unit 304B. Further, when the connection protrusion 414 of the rear connection unit 404 is inserted and connected to the rear end of the intermediate connection unit 304B, the irradiation on the rear connection unit 404 side is performed in the same manner as the connection between the detection unit 302B and the intermediate connection unit 304B. The side and light receiving side third fiber members 372 and 374 and the intermediate connection unit 304B side irradiation side and light receiving side second fiber members 360 and 362 are connected to each other and incorporated in the rear connection unit 404. A purge capillary (not shown) is connected to a purge capillary 398 built in the intermediate connection unit 304B.
[0090]
After connecting in this way, the lock screw 330 is loosened to release the locked state by the locking means 328, the push handle 416 of the rear connection unit 404 is pushed in the insertion direction indicated by the arrow 384, and as shown in FIG. When the irradiation unit 14 and the light receiving unit 16 of 302B are inserted until they reach a predetermined measurement region of the fluid flow path 4, the lock screw 330 is tightened to engage the tip of the locking screw 330 with the annular recess 320 of the intermediate connection unit 304B. As a result, the lock means 328 is locked, and the detection unit 302B, the intermediate connection unit 304B, and the rear connection unit 404 are locked and held in the state shown in FIG. Thereafter, the ends of the irradiation-side and light-receiving-side third fiber members 372 and 374 extending through the rear connection unit 404 are connected to a light-emitting source (not shown) and a light-receiving element (not shown). The preparatory work is performed, and the dust concentration in the fluid flowing through the fluid flow path 4 is measured after the preparatory work.
[0091]
After the dust concentration is finished, the lock screw 330 is loosened in the opposite manner as described above. Thus, the detection unit 302B, the intermediate connection unit 304B, and the rear connection unit 404 are pushed outward by the pressure of the fluid flowing through the fluid flow path 4. Then, when pushed out to a predetermined position, the lock screw 330 is tightened, and its tip is engaged with the annular recess 310 of the detection unit 302B, and the detection unit 302B is locked and held in the insertion tube structure 7B. Then, the rear connection unit 404 and the intermediate connection unit 304B are sequentially removed, and then the lid member 394 is attached to the flange 388 of the gas seal portion 12B. In this way, as shown in FIG. 17, the detection unit 302B can be stored in a state of being accommodated in the insertion tube structure 7B.
[0092]
In this embodiment, the connection units 304B and 404 are connected to the detection unit 302B. However, one or three or more connection units may be connected. What is necessary is just to comprise like the connection unit shown in FIGS. 14-17, and when connecting 3 or more, it is sufficient to make the back connection unit 404 one and the remainder to the intermediate connection unit 304B.
[0093]
In the various embodiments described above, the fluid flowing through the fluid flow path 4 flows to the irradiation unit 14 and the light receiving unit 16 of the detection unit 302 (302B) held by the insertion tube structure 7A (7B), and dust in the fluid is irradiated. In order to eliminate such an inconvenience, it may be configured as shown in FIG. 21, FIG. 22, or FIG. 23, for example.
[0094]
In the structure shown in FIG. 21, a cylindrical sleeve-like protective tube 502 is used, and this protective tube 502 is provided from the valve housing 210 of the ball valve unit 10 to the connecting member 202. The detection unit 302 (302B) is disposed inside the protective tube 502, and a pair of seal members 504 are attached to the inner peripheral surface of the distal end portion of the protective tube 502, and the seal member 504 is formed of, for example, a 0 ring.
[0095]
With this configuration, when the dust concentration is not measured, the detection unit 302 (302B) is locked and held in the insertion tube structure 7A (7B) as shown in FIG. The seal member 504 acts on the tip of the detection unit housing 306 (306B) to seal between the protective tube 502 and the detection unit housing 306 (306B). At this time, the irradiation unit 14 and the light receiving unit 16 of the detection unit 302 (302B) are located on the inner side (insertion tube mechanism 7A (7B)) side of the pair of seal members 504 and are covered with the protective tube 502. The fluid flowing through the fluid flow path 4 does not flow into the irradiation unit 14 and the light receiving unit 16 side, and contamination of the irradiation unit 14 and the light receiving unit 16 due to dust can be prevented. When measuring the dust concentration, the front end side of the detection unit 302 (302B) protrudes into the fluid flow path 4 through the inside of the pair of seal members 504.
[0096]
In the structure shown in FIG. 22, a cylindrical sleeve-like protective tube 512 is used. In this case as well, the protective tube 512 is provided from the valve housing 210 of the ball valve unit 10 to the connecting member 202. The detection unit 302 (302B) is disposed inside the protective tube 512, and a lid member 514 is provided at the tip of the protective tube 512 so as to be openable and closable. The lid member 514 is, for example, a spring member (not shown). By this, the front end opening of the protective tube 514 is kept sealed.
[0097]
With this configuration, when the dust concentration is not measured, the detection unit 302 (302B) is locked and held in the insertion tube structure 7A (7B) as shown in FIG. The member 514 seals the front end opening of the protective tube 512. At this time, the irradiation unit 14 and the light receiving unit 16 of the detection unit 302 (302B) are located on the inner side (insertion tube mechanism 7A (7B)) side of the lid member 514, and therefore the fluid flowing through the fluid flow path 4 is irradiated. Even if it comprises in this way, the contamination of the irradiation part 14 and the light-receiving part 16 by dust can be prevented. When measuring the dust concentration, the detection unit 302 (302B) is pushed out in the insertion direction, whereby the lid member 514 is rotated in the direction indicated by the arrow 516 to the open position indicated by the two-dot chain line, thereby protecting the tube 512. The distal end side of the detection unit 302 (302B) protrudes into the fluid flow path 4 through the opened distal end opening.
[0098]
In the structure shown in FIG. 23, a cylindrical sleeve-shaped protective tube 522 is used, and in this case, the protective tube 522 is rotatably covered with the detection unit housing 306 (306B) of the detection unit 302 (302B). Fitted. A measurement opening 524 is provided at a predetermined portion of the protective tube 522 corresponding to the irradiation unit 14 and the light receiving unit 16 of the detection unit 302 (302B). When the measurement opening 524 is located at the closed angle position shown in FIG. Is located on the opposite side of the detection unit 302 (302B) from the irradiation unit 14 and the light receiving unit 16, and at the open angle position rotated 180 degrees from the closed angle position, the measurement opening 524 has the irradiation unit 14 and the light receiving unit 16 Located opposite to.
[0099]
With this configuration, when the dust concentration is not measured, the detection unit 302 (302B) is locked and held in the insertion tube structure 7A (7B), as shown in FIG. The closed angle position shown in FIG. In such a holding state, the protective tube 522 covers the irradiation unit 14 and the light receiving unit 16 of the detection unit 302 (302B), and prevents the fluid flowing through the fluid flow path 4 from flowing into the irradiation unit 14 and the light receiving unit 16 side. be able to. When measuring the dust concentration, the protective tube 522 is held at an open angle position rotated 180 degrees from the closed angle position, whereby the irradiation unit 14 and the light receiving unit 16 of the detection unit 302 (302B) are moved outward. The dust concentration of the fluid that is exposed and flows in the fluid flow path 4 can be measured.
[0100]
  Above, dust measurement according to the present inventionApparatus embodimentHowever, the present inventionTakeThe present invention is not limited to the embodiments, and various changes and modifications can be made without departing from the scope of the present invention.
[0101]
For example, in the illustrated embodiment of the dust measuring apparatus, the detected light received by the light receiving unit 16 is guided to the second optical fiber 40 in association with the light receiving unit 16 being arranged on the distal end side of the detection unit housing 8. In order to guide the measurement light from the first optical fiber to the irradiating unit, on the contrary, when the irradiating unit is arranged on the front end side of the detecting unit housing, the reflecting mirror 56 is used. A reflector is used.
[0102]
  For example, as shownDust measuring device, The unit housing 254 is positioned and fixed concentrically with respect to the detection unit housing 8 by using the taper portion 274 of the tightening screw 271, but is not limited to such a configuration. For example, a spring-biased positioning lock piece may be used.
[0103]
  According to the dust measuring apparatus of the first aspect of the present invention, the measurement light is transmitted by the first optical fiber, and the detected light is transmitted by the second optical fiber. Can be thinned. In addition, an irradiation opening is provided on one side of the concave portion of the detection unit housing, and a light reception opening is provided on the other side. The irradiation opening and the light reception opening are opposed to each other in the axial direction of the detection unit housing. The outer shape of the housing can be effectively reduced. Furthermore, since one of the irradiation means and the light receiving means includes a reflecting mirror, the measurement light or the detected light can be transmitted without bending the first optical fiber or the second optical fiber when transmitting the measurement light or the detected light. It can be reflected and transmitted in the opposite direction, which can further reduce the outer shape of the detector housing, thereby facilitating insertion of the detector housing and inserting it into the fluid flow path through a small diameter hole. This makes it possible to measure the dust concentration in the fluid flowing through the small-diameter fluid passage. Further, the measurement light from the light source is irradiated from the irradiation opening toward the measurement region with an inclination of 10 to 30 degrees with respect to the axial direction of the detection unit housing, and the detected light from the measurement region is emitted from the detection unit housing. Since it is guided to the reflecting mirror with an inclination of 10 to 30 degrees with respect to the axial direction, the outer shape of the detector housing can be reduced, and the irradiation light from the irradiation opening can be directly received through the light receiving opening. Can be prevented.In addition, a pair of base-side seal members are provided at one end of the insertion path of the seal tube into which the detection unit housing is inserted, and a pair of tip-side seal members are provided at the other end side. Even if the detection unit housing having the insertion point is inserted into the fluid flow path through the insertion path, at least two seal members seal between the inner peripheral surface of the seal tube and the outer peripheral surface of the detection unit housing, and thus the fluid insertion path Leakage through can be reliably prevented.
  Moreover, according to the dust measuring apparatus of Claim 2 of this invention, since the structure regarding an irradiation means, a light-receiving means, and a detection housing is substantially the same as the dust measuring apparatus mentioned above, the dust measurement of Claim 1 is carried out. The same effect as the device is achieved. In addition, the unit housing is mounted on the detection unit housing, and this mounting is performed by a centering fixing mechanism, so that the unit housing can be positioned and fixed concentrically with respect to the detection unit housing. Therefore, when the standard member is mounted on the unit housing in such a fixed state, the standard detection portion of the standard member is accurately positioned in the measurement region, and thus the measurement value using the standard member can be accurately calibrated. it can.
[0104]
  Further, the claims of the present invention3According to the dust measuring device described in the above, the detected light introduced through the light receiving opening is reflected to the opposite side by the reflecting mirror and guided to the light receiving element through the second optical fiber. The housing can be reduced in size.
[0105]
  Further, the claims of the present invention4According to the dust measuring apparatus, the irradiation port cover and the light receiving port cover can be removed from the detection unit housing, and maintenance and replacement thereof can be easily performed. The detection unit housing is composed of first and second housing members that are detachably attached to each other, and the reflecting mirror is detachably attached to the second housing member. Can also be removed, and the reflector can be easily maintained and replaced.
[Brief description of the drawings]
FIG. 1 is a schematic view showing the entirety of an embodiment of a dust measuring apparatus according to the present invention.
FIG. 2 is a partial cross-sectional view showing a part of the dust measuring apparatus of FIG.
3 is a partial cross-sectional view showing the vicinity of an irradiation unit and a light receiving unit of the dust measuring device of FIG.
4 is a partially enlarged cross-sectional view showing an enlarged light receiving portion of the dust measuring device of FIG. 1;
5 is an exploded cross-sectional view showing a part of the vicinity of an irradiation unit and a light receiving unit of the dust measuring device in FIG.
FIG. 6 is a cross-sectional view showing a state when the ground detecting portion housing of the dust measuring device of FIG. 1 is inserted into the fluid flow path.
7 is a partial cross-sectional view showing a state where a detection unit housing is inserted a little from the state of FIG.
8 is a partial cross-sectional view showing a state where a detection unit housing is inserted a little from the state shown in FIG.
9 is a partial cross-sectional view showing a state where a detection unit housing is slightly inserted from the state shown in FIG.
10 is a partial cross-sectional view illustrating a state where a detection unit housing is further inserted from the state illustrated in FIG.
FIG. 11 is a partial cross-sectional view showing a state in which a unit housing is mounted on a modified detection unit housing.
FIG. 12 is a right side view showing a state where the unit housing is attached to the detection unit housing.
13 is a cross-sectional view taken along line XIII-XIII in FIG.
FIG. 14 is a cross-sectional view showing a state in which a detection unit in another embodiment of the dust measuring device is housed.
15 is a cross-sectional view showing a state before the connection unit is connected to the detection unit of the dust measuring device of FIG. 14;
16 is a cross-sectional view showing a state in which a connection unit is connected to the detection unit of the dust measuring device of FIG. 14;
FIG. 17 is a cross-sectional view showing a state in which a detection unit according to still another embodiment of the dust measuring device is housed.
18 is a cross-sectional view showing a state before the connection unit is connected to the detection unit of the dust measurement device of FIG. 17;
19 is a partial cross-sectional view showing a connection portion between a detection unit and a connection unit of the dust measurement device of FIG. 17;
20 is a cross-sectional view showing a state in which a connection unit is connected to the detection unit of the dust measurement device of FIG.
FIG. 21 is a partial cross-sectional view showing an embodiment of a structure for preventing dust from entering a detection unit.
FIG. 22 is a partial cross-sectional view showing another embodiment of the structure for preventing dust from entering the detection unit.
FIG. 23 is a partial cross-sectional view showing still another embodiment of a structure for preventing dust from entering a detection unit.
[Explanation of symbols]
2 Fluid piping
4 Fluid flow path
6 Dust
7,7A, 7B Insertion tube structure
8 Detector housing
10 Ball valve section
12, 12A, 12B Gas seal part
14 Irradiation part
16 Light receiver
20 Irradiation cover
24 Receiver cover
26 Measuring device body
28 Light source
30 Light receiving element
32 Dust concentration calculation means
38, 38A, 38B, 40, 40A, 40B Optical fiber
46,64 Cover mounting member
50 measurement area
54 Condensing lens
56 Reflector
226 Seal housing
232 Base side seal member
234 Tip side seal member
236, 238 Dust seal member
252 Calibration unit
254 unit housing
278 Mounting part
280 Standard member
302, 302B detection unit
304, 304B, 404 Connection unit
326 Fiber housing
328 Locking means
502,512,522 Protection tube

Claims

A detector housing having an irradiation opening and a light receiving opening, irradiation means for irradiating measurement light toward the measurement region through the irradiation opening, and light reception for receiving detected light from the measurement region through the light receiving opening A dust concentration measuring device comprising: a means, and a dust concentration calculating means for calculating the dust concentration by calculating the detected light received by the light receiving means as required,
A concave portion is provided at a predetermined portion of the detection unit housing, the irradiation opening is provided on one side of the concave portion, the light receiving opening is provided on the other side, and the irradiation opening and the light receiving opening are in the axial direction of the detection unit housing Facing the
The irradiating means includes a light emitting source for emitting measuring light and a first optical fiber for guiding the measuring light from the light emitting source to the irradiation aperture, and the light receiving means receives the detected light. And a second optical fiber for guiding the detected light introduced through the light receiving opening to the light receiving element,
The measurement light from the light source is irradiated through the first optical fiber from the irradiation opening toward the measurement region with an inclination of 10 to 30 degrees with respect to the axial direction of the detection unit housing. The light to be detected is introduced through the light receiving opening inclined by 10 to 30 degrees with respect to the axial direction of the detection unit housing,
One of the irradiation means and the light receiving means includes a reflecting mirror for reflecting light ,
Furthermore, the detection unit housing is inserted into the measurement region of the fluid flow path through an insertion path of a seal pipe that communicates with a fluid pipe that defines the fluid flow path, and at one end of the insertion path of the seal pipe, A pair of base side seal members are provided, and at the other end of the insertion path, a pair of tip side seal members are provided, and when inserted into the measurement region of the fluid flow path through the insertion path, The dust measurement is characterized in that a gap between the inner peripheral surface and the outer peripheral surface of the detection unit housing is sealed by at least two of the pair of base side seal members and the pair of distal end side seal members. apparatus.

A detector housing having an irradiation opening and a light receiving opening, irradiation means for irradiating measurement light toward the measurement region through the irradiation opening, and light reception for receiving detected light from the measurement region through the light receiving opening A dust concentration measuring device comprising: a means, and a dust concentration calculating means for calculating the dust concentration by calculating the detected light received by the light receiving means as required,
A concave portion is provided at a predetermined portion of the detection unit housing, the irradiation opening is provided on one side of the concave portion, the light receiving opening is provided on the other side, and the irradiation opening and the light receiving opening are in the axial direction of the detection unit housing Facing the
The irradiating means includes a light emitting source for emitting measuring light and a first optical fiber for guiding the measuring light from the light emitting source to the irradiation aperture, and the light receiving means receives the detected light. And a second optical fiber for guiding the detected light introduced through the light receiving opening to the light receiving element,
The measurement light from the light source is irradiated through the first optical fiber from the irradiation opening toward the measurement region with an inclination of 10 to 30 degrees with respect to the axial direction of the detection unit housing. The light to be detected is introduced through the light receiving opening inclined by 10 to 30 degrees with respect to the axial direction of the detection unit housing,
One of the irradiation means and the light receiving means includes a reflecting mirror for reflecting light ,
Further, a calibration unit for constituting a measurement value is detachably attached to the detection unit housing, and the calibration unit is used for calibrating the measurement value and a unit housing that is detachably attached to the detection unit housing. A standard member having a standard detection unit and mounted on the mounting portion of the unit housing; and a centering fixing mechanism for positioning and fixing the unit housing in a predetermined positional relationship with the detection unit housing. And
When the unit housing is mounted on the detection unit housing and centered and fixed by the centering fixing mechanism, the unit housing is positioned and fixed concentrically with respect to the detection unit housing. The dust measuring apparatus according to claim 1, wherein when the unit housing is mounted, the standard detecting portion of the standard member is positioned in the measurement region.

The light receiving means includes the reflecting mirror, the reflecting mirror is disposed between the light receiving opening and the second optical fiber, and the detected light introduced through the light receiving opening of the detection unit housing is: The dust measuring device according to claim 1 , wherein the dust measuring device is received by the light receiving element through the second optical fiber after being reflected by the reflecting mirror.

The detector housing includes first and second housing members that are detachably attached to each other, the irradiation opening is provided in the first housing member, and the light receiving opening is provided in the second housing member. An irradiation port cover is detachably attached to the irradiation opening, a light receiving cover is detachably attached to the light receiving opening, and the reflecting mirror is detachably attached to the second housing member. The dust measuring device according to claim 1 or 2 , wherein