JP3768781B2

JP3768781B2 - Tunnel disaster prevention equipment

Info

Publication number: JP3768781B2
Application number: JP2000174956A
Authority: JP
Inventors: 光栄五十嵐; 光広栗本
Original assignee: Hochiki Corp
Current assignee: Hochiki Corp
Priority date: 2000-06-12
Filing date: 2000-06-12
Publication date: 2006-04-19
Anticipated expiration: 2020-06-12
Also published as: JP2001357481A

Description

【０００１】
【発明の属する技術分野】
本発明は、防災受信盤から引き出された２系統の伝送路にトンネル内に設置した検出器や制御機器等の端末機器を接続すると共に所定間隔毎に中継増幅盤を接続してトンネル内を監視制御するトンネル防災設備に関する。
【０００２】
【従来の技術】
従来、自動車専用道路のトンネルに使用される防災設備として、例えば特開平１１−２８３１６７号及び特開平１１−２８３１６８号のトンネル防災システムが知られている。
【０００３】
このトンネル防災システムは、受信機からトンネル内に引き出されたＡ系統とＢ系統の伝送線路に複数の端末器を接続すると共に、一定間隔で線路の断線や短絡を検出してバックアップする機能を備えた中継増幅盤（補償装置）を接続している。
【０００４】
例えば断線監視は、通信状況をモニタして断線を判定した場合、正常系統により上位側との確認を行った後に、系統混合回路により正常系統の線路を異常系統の線路に接続し、断線位置まで信号を送り返すループバック接続を行う（特開平１１−２８３１６７号）。
【０００５】
また短絡監視は、下位の中継増幅盤との間の線路の短絡を監視し、短絡を検出すると下位との線路を切離すと共に、下位に位置する次の中継増幅盤に短絡を通知して上位との線路を切離させ、更に、系統混合回路により短絡系統の信号を正常系統に混合して短絡箇所を迂回させることで障害系統をバックアップする（特開平１１−２８３１６８号）。
【０００６】
【発明が解決しようとする課題】
しかしながら、このような従来のトンネル防災システムにあっては、通信異常から線路の断線を判定し、また通信時の過電流検出により線路の短絡を判定しているため、断線や短絡の状態判定が不確実になる恐れがある。
【０００７】
例えば、線路が中途半端な状態で短絡した場合は、過電流状態にはならないが通信異常とはなるため、中継増幅盤では断線と判定される。その結果、正常系統を障害系統に接続するループバック制御が行われ、このため正常な線路まで異常となり、中継増幅盤は通信不能に陥ってしまう。
【０００８】
この問題を解消するためには、断線と短絡を正確に区別して判定する必要があるが、通信中に伝送線路にはパルス信号が常時存在しており、そのため伝送線路の電圧レベルは常時変動しており、通信中の線路電圧の状態から正確に断線と短絡を区別して判定することは困難であった。
【０００９】
本発明は、線路電圧の監視により断線と短絡を正確に区別して判定することで適切なバックアップを可能とするトンネル防災設備を提供することを目的とする。
【００１０】
【課題を解決するための手段】
この目的を達成するため本発明は次のように構成する。本発明は、防災受信盤から引き出された２系統の伝送線路にトンネル内に設置した検出器や制御機器等の端末機器を接続すると共に所定間隔毎に中継増幅盤を接続してトンネル内を監視制御するトンネル防災設備を対象とする。
【００１１】
このようなトンネル防災設備につき本発明は、防災受信盤に、一定時間毎に監視処理を停止して線路監視タイミング信号を送信する監視タイミング設定部を設け、中継増幅盤に、上位側（防災受信盤側）の線路および下位側（終端側）の線路を送受信側から監視側に切替えて線路の状態を監視し、線路異常を検出した際にバックアップ状態に切替える線路異常監視部を設けたことを特徴とする。
【００１２】
このように本発明は、中継増幅器で線路の断線や短絡を検出する際には、防災受信盤による通信を一時的に停止し、その間に中継増幅盤間の線路に対し例えば一端に終端抵抗を接続し、他端から監視電圧を印加することで監視状態に切替え、その時の線路電圧から断線や短絡を判定する。
【００１３】
このとき線路には通信パルスは存在せず線路監視用の電圧のみが印加された状態となり、線路電圧によって正確に断線か短絡を判定し、より信頼性の高いバックアップができる。また、従来のように断線と短絡の判断に通信状態のモニタを必要としないため、短時間で判断可能となる。
【００１４】
ここで中継増幅盤の線路異常監視部は、上位側の線路及び下位側の線路の各々を送受信側と監視側との間で切替える監視切替回路と、上位側の２系統の線路間を接続する系統混在回路と、２系統の送受信部の間で各系統の通信信号を合成する信号合成回路と、防災受信盤からの線路監視タイミング信号を受信した際に、監視切替回路を監視側に一定時間切替えて上位側の線路を監視し、線路の断線を検出した場合は、前記系統混在回路の作動により２系統の線路間を接続して正常系統の信号を断線した線路にループバックし、線路の短絡を検出した場合は、監視切替回路を監視側の切替状態に維持して短絡した線路を切離すと共に、信号合成回路を作動して送受信部間での通信信号の合成により短絡箇所を迂回させる線路監視回路とを備える。
【００１５】
また線路監視回路は、検出後に線路の断線を検出しなくなった場合は、系統混在回路を復旧させ、また検出後に短絡を検出しなくなった場合は監視切替回路及び信号合成回路を復旧させる。これに対し従来システムでは、異常時に復帰動作を行うと通信異常を再度発生するため、中継増幅盤側で自動復帰させることは困難であり、短絡や断線の障害回復後にマニュアル操作による復帰が必要であり、本発明は、このような復帰のための操作を不要とする。
【００１６】
中継増幅盤の送受信回路は、通信中に過電流を検出した場合、監視切替回路を監視側に切替えて過電流を検出した線路を切離すと共に、信号合成回路を作動して各系統の通信信号の合成により過電流が検出された線路を迂回させる。また送受信回路は、検出後に過電流を検出しなくなった場合は、監視切替回路及び信号合成回路を復旧させる。
【００１７】
これによって、通信中に過電流を検出した際のバックアップ動作の回路部を、監視タイミングで異常を検出した場合のバックアップ動作の回路部とを共用でき、回路構成を簡単にする。
【００１８】
【発明の実施の形態】
図１は本発明によるトンネル防災設備の設備構成の説明図である。図１において、防災受信盤１は監視室などに設置されており、防災受信盤１からは上りトンネル１００Ａに対し伝送路２が引き出され、また下りトンネル１００Ｂに対し伝送路３が引き出されている。
【００１９】
上りトンネル１００Ａを例にとると、防災受信盤１から引き出された伝送路２はＡ系線路２ａとＢ系線路２ｂの２系統で構成されている。この実施形態にあっては、Ａ系線路２ａには上りトンネル１００Ａ内に一定間隔で設置された消火栓４と自動弁装置５が接続され、またＢ系線路２ｂには一定間隔で設置された火災検知器６が接続されている。
【００２０】
更にＡ系線路２ａとＢ系線路２ｂに対しては、通信距離による信号の減衰劣化を補償する中継増幅器７ａ，・・・７n-1 ，７ｎが一定間隔毎に接続されている。このような上りトンネル１００Ａの構成は下りトンネル１００Ｂにおいても同じである。
【００２１】
図２は、図１の防災受信盤１のブロック図である。防災受信盤１には、ＭＰＵ８、上りトンネル用伝送制御部９ａ、下りトンネル用伝送制御部９ｂ、表示操作部１０及び移報部１１が設けられている。上りトンネル用伝送制御部９ａからは、上りトンネル１００Ａに対する２系統の線路、即ちＡ系線路２ａとＢ系線路２ｂが引き出されている。また下りトンネル用伝送制御部９ｂからは下りトンネル１００Ｂに対するＡ系統線路３ａとＢ系統線路３ｂが引き出されている。
【００２２】
ＭＰＵ８には呼出応答部１２と監視タイミング設定部１３の機能が設けられる。呼出応答部１２は、上りトンネル１００Ａ側を例にとると、上りトンネル用伝送制御部９ａから引き出されているＡ系線路２ａとＢ系線路２ｂの両方に接続している図１の消火栓４、自動弁装置５及び火災検知器６を含む端末機器との間で、アドレスを特定した通信を行う。
【００２３】
具体的には、呼出応答部１２は端末機器の状態を呼び出すための呼出信号（呼出コマンド）を端末アドレスを順次指定してＡ系線路２ａとＢ系線路２ｂの両方に同時に送信する処理を繰り返している。ここで端末アドレスは、Ａ系線路２ａとＢ系線路２ｂに接続している端末機器につき異なるアドレスを割当てている。
【００２４】
端末機器にあっては、防災受信盤１からの呼出信号から自己アドレスを認識すると、そのときの検出状態や装置の状態などの応答信号（応答コマンドとデータ）を作成し、防災受信盤１に送信する。この場合、Ａ系線路２ａとＢ系線路２ｂに接続している端末機器は全てアドレスが異なることから、必ずアドレス一致となった１つの端末機器のみがＡ系線路２ａまたＢ系線路２ｂを使用して応答信号を送信する。
【００２５】
このような呼出応答部１２からの通信信号は、上りトンネル用伝送制御部９ａから引き出されているＡ系統線路２ａとＢ系統線路２ｂの双方に同一の通信信号が送信される。
【００２６】
更に、防災受信盤１からの呼出信号は、防災受信盤側を上位、終端側を下位とすると、下り信号となり、この下り信号は電圧信号（電圧モード）として送信される。また端末機器からの応答信号は上り信号となり、上り信号は電流信号（電流モード）として送信される。この場合、Ａ系線路２ａとＢ系線路２ｂの各々は、電圧信号である下り信号と電流信号である上り信号の双方向伝送を行うことになる。
【００２７】
監視タイミング設定部１３は、一定の時間間隔ごとに、例えば５秒に１回程度の間隔で端末機器に対し線路監視タイミング信号を、送信先を特定しないブロードキャストあるいはマルチキャストとしての一斉電文として送信する。
【００２８】
この線路監視タイミング信号は、図１のトンネル内に設置している中継増幅盤７ａ〜７ｎに対し線路の断線と短絡を監視するための監視動作を行わせる信号である。また線路監視タイミング信号を送信した際には呼出応答部１２による通常の通信は停止される。
【００２９】
図３は、防災受信盤１から一定時間間隔で送信される線路監視タイミング信号と端末側における監視タイミング信号による監視動作のタイミングチャートである。
【００３０】
図３（Ａ）は防災受信盤１からの通信信号の伝送状態であり、予め定めた一定間隔例えばＴ１＝５秒ごとに通常通信における呼出応答を停止し、線路監視タイミング信号を端末に送信している。
【００３１】
図３（Ｂ）は線路監視タイミング信号を取り出して拡大しており、例えば線路監視タイミング信号として特定のビット列に続いて、チェックサムＣＫＳＭを設けたコマンドフォーマットを持つ線路監視タイミング信号を送信している。
【００３２】
この線路監視タイミング信号を端末機器が受信すると、監視切替スイッチ信号を図３（Ｃ）のようにＴ２＝２０ｍｓの間出力し、中継増幅盤に接続している上位側（防災受信盤１側）及び終端側のそれぞれの線路を中継増幅用の送受信回路から線路監視回路に切り替え、線路の断線と短絡の判定を行う。
【００３３】
中継増幅盤で線路が断線監視回路に切り替わると、下位側の中継増幅盤から上位側の中継増幅盤に対し監視電圧が出力され、この線路監視電圧を図３（Ｄ）の電圧判定値の読込タイミングに示すようにＴ３＝１５ｍｓ後に読み込むことで、正常か、断線または短絡かを判定する。
【００３４】
図４は、図１のトンネル内に設置している中継増幅盤７の実施形態のブロック図である。図４において、中継増幅盤７は、Ａ系線路及びＢ系線路の各線路を２線式とした場合の実施形態である。
【００３５】
中継増幅盤７にはＡ系線路２ａとＢ系線路２ｂが上位側及び下位側のそれぞれに接続されている。これらＡ系線路２ａ，Ｂ系線路２ｂに対応して、中継増幅盤７には、Ａ系統については送受信回路１４ａ，１４ｂが設けられ、またＢ系統については送受信回路１４ｃ，１４ｄが設けられている。送受信回路１４ａ〜１４ｄは、下り方向は呼出電圧信号を増幅する電圧ドライバを備え、上り方向は応答電流信号を受信判別して定電流回路の作動で電流信号を送信する電流ドライバを備えている。
【００３６】
具体的には、下り信号（電圧呼出信号）に対しては、送受信回路１４ａ，１４ｃが電圧受信部となり、送受信回路１４ｂ，１４ｄが電圧送信部となる。また上り信号（電流応答信号）に対しては、送受信回路１４ｂ，１４ｄが電流受信部となり、送受信回路１４ａ，１４ｃが電流送信部となる。
【００３７】
また中継増幅盤７にはＡ系線路２ａに対応して線路監視回路１５ａ，１５ｂが設けられ、またＢ系線路２ｂに対応して線路監視回路１５ｃ，１５ｄが設けられている。このような送受信回路１４ａ〜１４ｄ及び線路監視回路１５ａ〜１５ｄに対し、それぞれに対し対応する線路側を切替接続する監視切替回路１６ａ，１６ｂ，１６ｃ，１６ｄが設けられている。
【００３８】
監視切替回路１６ａを例にとると、＋側線路と−側線路に対応して２つの切替スイッチａ１，ａ２が設けられている。切替スイッチａ１，ａ２は、送受信回路１４ａで受信した防災受信盤１からの線路監視タイミング信号により、図３（Ｃ）のようにＴ２＝２０ｍｓの間、線路監視回路１５ａ側に切り替えられる。
【００３９】
防災受信盤１からの線路監視タイミング信号は送受信回路１４ａ，１４ｃで検出され、線路監視タイミング信号を受信すると、ＯＲ回路１７を介して図３（Ｃ）に示した監視切替スイッチ信号Ｅ１を監視切替回路１６ａ〜１６ｄのそれぞれに出力する。
【００４０】
このため、線路監視タイミング信号を受信した際には監視切替回路１６ａの切替スイッチａ１，ａ２、監視切替回路１６ｂの切替スイッチｂ１，ｂ２、監視切替回路１６ｃの切替スイッチｃ１，ｃ２、更に監視切替回路１６ｄの切替スイッチｄ１，ｄ２のそれぞれが、Ｔ２＝２０ｍｓの間、送受信回路１４ａ〜１４ｄ側から線路監視回路１５ａ〜１５ｄ側に切り替えられる。
【００４１】
線路監視回路１５ａ，１５ｃは、切替スイッチａ１，ａ２及び切替スイッチｃ１，ｃ２が監視側に切り替えられた状態で、上位側のＡ系線路２ａ及び上位側のＢ系線路２ｂに対し所定の監視電圧例えば＋４８Ｖを出力する。
【００４２】
一方、下位側に設けている線路監視回路１５ｂ，１５ｄは終端抵抗Ｒｓを内蔵しており、切替スイッチｂ１，ｂ２及び切替スイッチｄ１，ｄ２を監視側に切り替えると、下位側のＡ系線路２ａとＢ系線路２ｂのそれぞれに終端抵抗Ｒｓを接続する。
【００４３】
これによって、監視タイミング信号を受信した際に中継増幅盤７にあっては、下位側に位置する中継増幅盤から上位側に位置する中継増幅盤との間の線路に対し監視電圧を出力し、上位側の中継増幅盤に設けている終端抵抗を通る監視ループが形成される。
【００４４】
図５は線路監視タイミング信号を受信した際に、隣接する中継増幅盤の間で形成される監視用の等価回路を示している。この等価回路は下位の中継増幅盤７ｂの線路監視回路１５ａから上位の中継増幅盤７ａの線路監視回路１５ｂとの間で＋４８Ｖ，Ｚ１，Ｒｓ，Ｚ２及びグランドとなる監視ループが形成される。
【００４５】
ここでＺ１，Ｚ２は、線路監視回路１５ａにおける回路のインピーダンス成分を表わしている。このため、監視ループを形成した際には主線路監視回路１５ａ，１５ｂのそれぞれで所定の位置の電圧、例えば終端抵抗Ｒｓの両端電圧を読み込んで、正常、断線または短絡を判定する。
【００４６】
正常時にあっては、終端抵抗Ｒｓは監視電圧＋４８Ｖと回路インピーダンスＺ１，Ｚ２の直列接続による分圧で決まる所定範囲の電圧が生じており、この正常時の電圧を読み込むことで線路の正常を判定できる。
【００４７】
また線路が断線した場合には、線路監視回路１５ａ側にあっては終端抵抗Ｒｓの両端電圧は電源電圧＋４８Ｖとなる。一方、線路監視回路１５ｂ側にあっては断線により終端抵抗Ｒｓの両端からは電圧が得られない。
【００４８】
更に、線路が短絡した場合には、線路監視回路１５ａにあってはインピーダンス成分Ｚ１に流れる短絡電流による発生電圧だけ電源電圧＋４８Ｖから低い電圧となる。これに対し線路監視回路１５ｂ側にあっては、短絡によりごく僅かな線路電圧しか加わらない状態となる。このような監視タイミング信号を受信した際の監視ループの形成は、中継増幅盤７におけるＢ系統側の線路監視回路１５ｃ，１５ｄについても同様である。
【００４９】
ここで中継増幅盤７に設けている上位側の線路監視回路１５ａ，１５ｃは、断線と短絡の両方を検出する。これに対し下位側に設けている線路監視回路１５ｂ，１５ｄは、断線検出は必要なく短絡検出のみを行うようにしている。
【００５０】
両側に設けている線路監視回路１５ａまたは線路監視回路１５ｃで上位側のＡ系線路２ａまたはＢ系線路２ｂの断線を判定すると、監視切替回路１６ａ，１６ｃの前段に設けている系統混合回路１８に対し切替信号Ｅ２ａまたはＥ２ｃを出力し、混合スイッチｅ１，ｅ２をオンし、正常な系統の線路を断線した系統の線路に接続し、正常系統の線路からの電圧呼出信号を系統混合回路１８を介して、断線を生じた系統の線路に送り込み、断線した位置までの間に接続している端末機器に対しループバックによる信号供給を行う。
【００５１】
一方、線路監視回路１５ａ，１５ｃで線路２ａ，２ｂの短絡を検出した場合には、監視切替回路１６ａ，１６ｃに切替保持信号Ｅ３ａ，Ｅ３ｃを出力し、線路監視タイミング信号により監視側に切り替わっている切替スイッチａ１，ａ２または切替スイッチｃ１，ｃ２を切り替わった状態に保持し、これによって短絡した線路を切り離す。
【００５２】
線路監視回路１５ａ又は１５ｃで短絡を検出した場合には、上位側に隣接して位置する中継増幅盤の線路監視回路１５ｂ，１５ｄにおいても短絡が検出されており、線路監視回路１５ｂ，１５ｄは短絡判定に基づき監視切替回路１６ｂ，１６ｄに切替保持信号Ｅ３ｂ，Ｅ３ｄを出力し、切替保持信号Ｅ３ｂ，Ｅ３ｄにより監視側に切り替わっている切替スイッチｂ１，ｂ２又は切替スイッチｄ１，ｄ３の切替状態を維持することで、短絡した線路を切り離す。
【００５３】
更に線路監視回路１５ａ〜１５ｄは、短絡検出と同時に信号合成回路２０に対し作動信号Ｅ４ａ〜Ｅ４ｄを出力し、信号合成回路２０によるＡ系統とＢ系統の信号の合成を中継増幅盤７内で行わせる。この信号合成回路２０によって、短絡により切り離された障害系統の通信信号を正常な系統に迂回させて、短絡線路を回避した通信を可能とする。
【００５４】
図６は中継増幅盤７ａ，７ｂの間のＡ系線路２ａで断線２１が発生した場合の動作である。
【００５５】
中継増幅盤７ａ，７ｂのそれぞれで防災受信盤１からの線路監視タイミング信号が受信されると、送受信回路１４ａ，１４ｃからの監視切替スイッチ信号Ｅ１がＯＲ回路よりそれぞれの監視切替回路１６ａ〜１６ｄに出力され、監視側に切り替えられる。
【００５６】
このとき中継増幅盤７ａと中継増幅盤７ｂの間のＡ系線路２ａに断線２１が発生していたとすると、下位側に位置する中継増幅盤７ｂの線路監視回路１５ａが断線２１を検出し、系統混合回路１８に切替信号Ｅ２ａを出力し、図示のようにスイッチｅ１，ｅ２をオンする。
【００５７】
線路監視タイミング信号の受信からＴ２＝２０ｍｓを経過すると、中継増幅盤７ａ，７ｂに設けている監視切替回路１６ａ〜１６ｄの切替スイッチは図示のように送受信回路１４ａ〜１４ｄ側に戻り、防災受信盤１からは通常の呼出信号が再び送られ、端末側からも応答信号が送られてくる。
【００５８】
このとき断線２１に対し下位に位置する中継増幅盤７ｂの系統混合回路１８のスイッチｅ１，ｅ２がオンしたループバック状態となっており、このため断線２１の下位側に位置する端末機器例えば消火栓４に対しては、正常なＢ系統線路２ｂから受信した呼出信号が系統混合回路１８を通って断線２１までの端末機器に対しループバックによって供給され、これによって断線２１が起きても継続して端末機器との間で正常な通信状態を維持することができる。
【００５９】
図７は中継増幅盤７ａと中継増幅盤７ｂのＡ系線路２ａで短絡２２が起きた場合の動作である。
【００６０】
線路監視タイミング信号の受信で監視切替回路１６ａ〜１６ｄを監視側に切り替えると、短絡２２が起きている下位側の中継増幅盤７ｂの線路監視回路１５ａで短絡が検出され、同時に上位側に位置する中継増幅盤７ａの線路監視回路１５ｂにおいても同時に短絡が検出される。
【００６１】
短絡を検出した線路監視回路１５ａは、監視切替回路１６ａに切替保持信号Ｅ３ａを出力して、線路監視タイミング信号の受信からＴ２＝２０ｍｓを経過して監視切替スイッチ信号Ｅ１がなくなっても、監視切替回路１６ａの切替スイッチａ１，ａ２を図示の監視側の切替状態、即ち送受信回路１６ａに対し短絡２２が起きた線路２ａを切り離した状態を維持する。
【００６２】
同時に中継増幅盤７ａの線路監視回路１５ｂも、監視切替回路１６ｂに切替保持信号Ｅ３ｂを出力し、線路監視スイッチ信号Ｅ１が断たれても、切替スイッチｂ１，ｂ２を図示の監視側、即ち短絡２２が起きた線路を送受信回路１４ｂから切り離した状態に保持する。
【００６３】
更に中継増幅盤７ｂの線路監視回路１５ａは、作動信号Ｅ４ａを信号合成回路２０に出力して作動し、中継増幅盤内でＡ系統の通信信号とＢ系統の通信信号を合成する。同時に中継増幅盤７ａにあっても、線路監視回路１５ｂからの作動信号で信号合成回路２０が作動し、中継増幅盤内においてＡ系統の通信信号とＢ系統の通信信号が合成される。
【００６４】
この結果、例えば防災受信盤から中継増幅盤７ａで受信した呼出信号は、送受信回路１４ａ、信号合成回路２０、送受信回路１４ｄを通ってＢ系線路２ｂにより中継増幅盤７ｂに送られ、中継増幅盤７ｂにあっては送受信回路１４ｃ、信号合成回路２０、更に送受信回路１４ｂを通って下位のＡ系線路２ａに送信される。即ち、短絡２２を生じた前後の中継増幅盤７ａ，７ｂが短絡２２を起こした線路を切り離すと同時に、正常なＢ系統線路２ｂに対しＡ系統の通信信号を迂回するバックアップ動作を行う。
【００６５】
更に図６のような断線に対するループバックを行うバックアップ状態、または図７の短絡に対し短絡線路を迂回するバックアップ動作の状態において、断線２１や短絡２２が解消すると自動的に正常な通信状態に復旧することができる。
【００６６】
例えば図６で断線２１が修理などにより復旧すると、防災受信盤１から復旧後の最初に線路監視タイミング信号が受信された時、中継増幅盤７ｂの線路監視回路１５ａが線路の正常を判定すると、系統混合回路１８にそれまで出力していた作動信号Ｅ２ａを停止し、系統混合回路１８のスイッチｅ１，ｅ２がオフすることでループバック状態を自動的に解消して正常な通信状態に復旧することができる。
【００６７】
また図７の短絡状態で短絡２２が修理などにより復旧すると、復旧から最初に線路監視タイミング信号が受信された時、短絡を検出していた中継増幅盤７ｂの線路監視回路１５ａ及び中継増幅盤７ａの線路監視回路１５ｂのそれぞれで線路が正常であることが判定され、切替保持信号Ｅ３ａ，Ｅ３ｂが停止して、切離し状態にあった監視切替回路１６ａ，１６ｂの切替スイッチａ１，ａ２及びｂ１，ｂ２が送受信回路側に戻り、同時に作動信号Ｅ４ａ，Ｅ４ｂが停止して信号合成回路２０の合成動作が停止し、これによって正常な通信動作の状態に自動復旧することができる。
【００６８】
更に図４に示した本発明における中継増幅盤７にあっては、送受信回路１４ａ〜１４ｄのそれぞれで通信中における過電流を判定している。通信中に送受信回路１４ａ〜１４ｄが過電流を判定すると、それぞれの監視切替回路１６ａ〜１６ｄに対し切離し信号Ｅ５ａ〜Ｅ５ｄを出力して、過電流を検出した線路側を切り離す。同時に信号合成回路２０に作動信号（図示せず）を出力する。
【００６９】
これによって、通信中に過電流を検出した場合には、図７に示した線路監視タイミングで短絡２２を検出した場合と同様にして過電流を生じた線路を切り離し、同時に切離し位置での正常な系統の線路に障害系統の信号を迂回させるバックアップ動作を行う。この送受信回路１４ａ〜１４ｄによる過電流検出によるバックアップ動作についても、過電流状態が解消されると自動的に正常な通信状態に復旧することができる。
【００７０】
図８は、本発明の伝送路を４線式とした場合の防災受信盤１のブロック図である。４線式の場合には、例えば上りトンネル用伝送制御部９ａからの伝送路は、Ａ系伝送路３０ａとＢ系伝送路３０ｂとの２系統で構成され、更に、Ａ系統伝送線路３０ａはＡ系下り線路３１とＡ系上り線路３２で構成され、Ｂ系伝送路３０ｂは、Ｂ系下り線路３３とＢ系上り線路３４で構成される。
【００７１】
Ａ系下り線路３１とＢ系下り線路３３には防災受信盤１から電圧モードで電圧呼出信号が送信される。Ａ系上り線路３２とＢ系上り線路３４には端末機器から電流モードの電流応答信号が伝送される。この場合、Ａ系統とＢ系統のいずれか一方を優先線路とし、優先系統を通常通信に使用し、他の系統は断線や短絡時のバックアップ系統とする。
【００７２】
この場合、中継増幅器７としては、上位４回線と下位４回線が接続されることになるので、上位側の４回線に対しては図７の上位側の各線路と同じ回路を設け、下位側の４回線についても、図７の下位側の各線路と同じ回路を設ければよい。
【００７３】
この点は、下りトンネル用伝送制御部９ｂについても同様であり、Ａ系伝送路４０ａとＢ系伝送路４０ｂとの２系統で構成され、更に、Ａ系統伝送線路４０ａはＡ系下り線路４１とＡ系上り線路４２で構成され、Ｂ系伝送路４０ｂは、Ｂ系下り線路４３とＢ系上り線路４４で構成される。
【００７４】
尚、上記の実施形態における防災受信盤１からの通常時の呼出応答については、端末機器を順次指定したポーリングによる情報のやり取りを例にとっているが、防災受信盤１側及び端末機器側における任意のイベントの発生時に割込み的に情報を通信するようにしてもよいことはもちろんである。
【００７５】
更に本発明は、その目的と利点を損なわない適宜の変形を含み、また本発明は上記の実施形態に示した数値による限定は受けない。
【００７６】
【発明の効果】
以上説明してきたように本発明によれば、中継増幅盤で線路の断線や短絡を検出する際には、防災受信盤と端末機器との間の通常の呼出応答の通信を一時的に停止し、その間に中継増幅盤によって線路の上位側に終端抵抗を接続し下位側から監視電圧を印加することで線路の断線や短絡を判定し、線路に通信信号が存在しない安定した状態で断線または短絡を判定することから、線路電圧によって正確に断線か短絡かが判定でき、より信頼性の高いバックアップができる。
【００７７】
また断線と短絡の判断に通常の通信状態のモニタを必要としないため、短時間で線路の状態を判断することができる。
【００７８】
更に、線路の断線または短絡を検出してバックアップ動作を行った後に障害が解消されると、自動的に正常な通信状態に復旧でき、人的な復旧動作を必要としない分、維持管理が容易である。
【図面の簡単な説明】
【図１】本発明の設備構成の説明図
【図２】図１の防災受信盤のブロック図
【図３】本発明の監視動作のタイミングチャート
【図４】図１の中継増幅盤のブロック図
【図５】監視タイミングで中継器間に形成される線路監視ループの等価回路図
【図６】線路断線時の動作説明図
【図７】線路短絡時の動作説明図
【図８】４線式とした場合の防災受信盤のブロック図
【符号の説明】
１：防災受信盤
２，３：伝送路
２ａ，３ａ：Ａ系線路
２ｂ，３ｂ：Ｂ系線路
４：消火栓
５：自動弁装置
６：検知器
７，７ａ〜７ｎ：中継増幅盤
８：ＭＰＵ
９ａ：上りトンネル用伝送制御部
９ｂ：下りトンネル用伝送制御部
１０：表示操作部
１１：移報部
１２：呼出応答部
１３：監視タイミング設定部
１４ａ〜１４ｄ：送受信回路
１５ａ〜１５ｄ：線路監視回路
１６ａ〜１６ｄ：監視切替回路
１７：ＯＲ回路
１８：系統混合回路
２０：信号合成回路
２１：断線
２２：短絡
１００Ａ：上りトンネル
１００Ｂ：下りトンネル[0001]
BACKGROUND OF THE INVENTION
The present invention monitors the inside of a tunnel by connecting terminal equipment such as detectors and control equipment installed in the tunnel to two transmission lines drawn from the disaster prevention reception board, and connecting relay amplification boards at predetermined intervals. It relates to tunnel disaster prevention equipment to be controlled.
[0002]
[Prior art]
Conventionally, tunnel disaster prevention systems disclosed in, for example, Japanese Patent Application Laid-Open No. 11-283167 and Japanese Patent Application Laid-Open No. 11-283168 have been known as disaster prevention equipment used for tunnels on automobile roads.
[0003]
This tunnel disaster prevention system has a function to connect a plurality of terminals to the transmission lines of the A system and the B system drawn from the receiver into the tunnel, and to detect and back up the line breaks and short circuits at regular intervals. A relay amplifier panel (compensator) is connected.
[0004]
For example, in the disconnection monitoring, if the disconnection is determined by monitoring the communication status, after confirming with the upper side by the normal system, the normal system line is connected to the abnormal system line by the system mixing circuit, and the disconnection position is reached. A loopback connection for sending back signals is performed (Japanese Patent Laid-Open No. 11-283167).
[0005]
In addition, the short circuit monitoring monitors the short circuit of the line with the lower relay amplifier board, and when a short circuit is detected, disconnects the lower line and notifies the next relay amplifier board located in the lower position of the short circuit. Further, the faulty system is backed up by separating the line from the line and further mixing the signal of the short circuit system into the normal system by the system mixing circuit to bypass the short circuit point (Japanese Patent Laid-Open No. 11-283168).
[0006]
[Problems to be solved by the invention]
However, in such a conventional tunnel disaster prevention system, the disconnection of the line is determined from the communication abnormality, and the short circuit of the line is determined by the overcurrent detection at the time of communication. There is a risk of uncertainty.
[0007]
For example, when the line is short-circuited in a halfway state, an overcurrent state does not occur, but a communication abnormality occurs. Therefore, the relay amplifier panel determines that the line is disconnected. As a result, loopback control for connecting the normal system to the faulty system is performed, so that even the normal line becomes abnormal, and the relay amplifier board becomes incapable of communication.
[0008]
In order to solve this problem, it is necessary to accurately distinguish between a disconnection and a short circuit, but a pulse signal is always present in the transmission line during communication, so the voltage level of the transmission line constantly fluctuates. Therefore, it is difficult to accurately distinguish and determine the disconnection and the short circuit from the state of the line voltage during communication.
[0009]
An object of this invention is to provide the tunnel disaster prevention equipment which enables appropriate backup by distinguishing and determining a disconnection and a short circuit correctly by monitoring a line voltage.
[0010]
[Means for Solving the Problems]
In order to achieve this object, the present invention is configured as follows. The present invention monitors the inside of a tunnel by connecting terminal equipment such as detectors and control equipment installed in the tunnel to two transmission lines drawn from the disaster prevention reception board and connecting relay amplifier boards at predetermined intervals. Targets tunnel disaster prevention equipment to be controlled.
[0011]
With respect to such a tunnel disaster prevention equipment, the present invention provides a disaster prevention receiving board with a monitoring timing setting unit that stops the monitoring process at regular intervals and transmits a line monitoring timing signal. The board side) and lower side (termination side) lines are switched from the transmission / reception side to the monitoring side to monitor the line condition, and when a line abnormality is detected, a line abnormality monitoring unit is provided to switch to the backup state. Features.
[0012]
As described above, the present invention temporarily stops the communication by the disaster prevention receiving board when detecting the disconnection or short circuit of the line with the relay amplifier, and in the meantime, for example, the terminal resistance is set at one end with respect to the line between the relay amplifier boards. Connected and applied to the monitoring state by applying a monitoring voltage from the other end, and disconnection or short circuit is determined from the line voltage at that time.
[0013]
At this time, there is no communication pulse on the line, and only the line monitoring voltage is applied, and the disconnection or short-circuit is accurately determined by the line voltage, so that more reliable backup can be performed. Further, since it is not necessary to monitor the communication state for the determination of the disconnection and the short circuit as in the prior art, the determination can be made in a short time.
[0014]
Here, the line anomaly monitoring section of the relay amplifier panel connects between the upper switching line and the monitoring switching circuit for switching each of the lower line and the lower line between the transmission / reception side and the monitoring side, and the upper two lines. When a mixed system circuit, a signal synthesis circuit that synthesizes communication signals of each system between two transmission / reception units, and a line monitoring timing signal from the disaster prevention receiver, the monitoring switching circuit is set to the monitoring side for a certain period of time. When switching and monitoring the upper line, and detecting the disconnection of the line, the system mixed circuit is operated to connect the two lines and loop back to the disconnected line of the normal signal. When a short circuit is detected, the monitoring switching circuit is maintained in the switching state on the monitoring side to disconnect the shorted line, and the signal synthesizing circuit is activated to bypass the short circuit portion by synthesizing communication signals between the transmitting and receiving units. Line monitoring circuit
[0015]
Further, the line monitoring circuit restores the system mixed circuit when the disconnection of the line is not detected after the detection, and restores the monitoring switching circuit and the signal synthesis circuit when the short circuit is not detected after the detection. On the other hand, in the conventional system, if a recovery operation is performed in the event of an error, a communication error will occur again, so it is difficult to automatically recover from the relay amplifier panel, and manual recovery is required after recovery from a short circuit or disconnection failure. In addition, the present invention does not require an operation for such return.
[0016]
When an overcurrent is detected during communication, the transmission / reception circuit of the relay amplifier panel switches the monitoring switching circuit to the monitoring side, disconnects the line where the overcurrent is detected, and activates the signal synthesis circuit to communicate the communication signal of each system. The line where the overcurrent is detected is bypassed by the synthesis of. The transmission / reception circuit restores the monitoring switching circuit and the signal synthesis circuit when the overcurrent is no longer detected after the detection.
[0017]
As a result, the circuit unit for the backup operation when an overcurrent is detected during communication can be shared with the circuit unit for the backup operation when an abnormality is detected at the monitoring timing, thereby simplifying the circuit configuration.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an explanatory diagram of the equipment configuration of a tunnel disaster prevention equipment according to the present invention. In FIG. 1, the disaster prevention receiving board 1 is installed in a monitoring room or the like, and the transmission path 2 is drawn out from the disaster prevention receiving board 1 to the up tunnel 100A, and the transmission line 3 is drawn out from the down tunnel 100B. .
[0019]
Taking the upstream tunnel 100A as an example, the transmission path 2 drawn out from the disaster prevention receiving board 1 is composed of two systems of an A-system line 2a and a B-system line 2b. In this embodiment, the fire hydrant 4 and the automatic valve device 5 installed at regular intervals in the upstream tunnel 100A are connected to the A system line 2a, and the fire installed at regular intervals to the B system line 2b. A detector 6 is connected.
[0020]
Further, relay amplifiers 7a,... 7n-1, 7n for compensating for signal attenuation due to communication distance are connected to the A system line 2a and the B system line 2b at regular intervals. The configuration of such an upstream tunnel 100A is the same in the downstream tunnel 100B.
[0021]
FIG. 2 is a block diagram of the disaster prevention receiving board 1 of FIG. The disaster prevention receiving board 1 is provided with an MPU 8, an uplink tunnel transmission control unit 9 a, a downlink tunnel transmission control unit 9 b, a display operation unit 10, and a transfer unit 11. From the transmission control unit 9a for the upstream tunnel, two lines for the upstream tunnel 100A, that is, the A system line 2a and the B system line 2b are drawn out. Further, the A system line 3a and the B system line 3b for the down tunnel 100B are drawn from the down tunnel transmission control unit 9b.
[0022]
The MPU 8 is provided with functions of a call response unit 12 and a monitoring timing setting unit 13. Taking the upstream tunnel 100A side as an example, the call response unit 12 is connected to both the A system line 2a and the B system line 2b drawn from the upstream tunnel transmission control unit 9a, and the fire hydrant 4 of FIG. Communication with the specified address is performed with the terminal device including the automatic valve device 5 and the fire detector 6.
[0023]
Specifically, the call response unit 12 repeats the process of sequentially transmitting a call signal (call command) for calling the state of the terminal device to both the A system line 2a and the B system line 2b by sequentially specifying the terminal addresses. ing. Here, different terminal addresses are assigned to terminal devices connected to the A-system line 2a and the B-system line 2b.
[0024]
In the terminal device, when the self-address is recognized from the call signal from the disaster prevention receiving board 1, a response signal (response command and data) such as a detection state and a device state at that time is created, and the disaster prevention receiving board 1 Send. In this case, since all the terminal devices connected to the A system line 2a and the B system line 2b have different addresses, only one terminal device that always has an address match uses the A system line 2a or the B system line 2b. Then, a response signal is transmitted.
[0025]
As for the communication signal from the call response unit 12, the same communication signal is transmitted to both the A system line 2a and the B system line 2b drawn from the uplink transmission control unit 9a.
[0026]
Furthermore, the call signal from the disaster prevention receiving board 1 becomes a down signal when the disaster prevention receiving board side is the upper side and the termination side is the lower side, and this down signal is transmitted as a voltage signal (voltage mode). The response signal from the terminal device is an upstream signal, and the upstream signal is transmitted as a current signal (current mode). In this case, each of the A-system line 2a and the B-system line 2b performs bidirectional transmission of a downstream signal that is a voltage signal and an upstream signal that is a current signal.
[0027]
The monitoring timing setting unit 13 transmits a line monitoring timing signal to the terminal device at a fixed time interval, for example, about once every 5 seconds, as a broadcast message or multicast message that does not specify a transmission destination.
[0028]
This line monitoring timing signal is a signal that causes the relay amplifier boards 7a to 7n installed in the tunnel of FIG. 1 to perform a monitoring operation for monitoring the disconnection and short circuit of the line. When the line monitoring timing signal is transmitted, normal communication by the call response unit 12 is stopped.
[0029]
FIG. 3 is a timing chart of the monitoring operation by the line monitoring timing signal transmitted from the disaster prevention receiving board 1 at regular time intervals and the monitoring timing signal on the terminal side.
[0030]
FIG. 3 (A) shows the transmission state of the communication signal from the disaster prevention receiving board 1, and stops the paging response in the normal communication every predetermined interval, for example, T1 = 5 seconds, and transmits the line monitoring timing signal to the terminal. ing.
[0031]
In FIG. 3B, the line monitoring timing signal is extracted and expanded. For example, a line monitoring timing signal having a command format provided with a checksum CKSM is transmitted as a line monitoring timing signal following a specific bit string. .
[0032]
When the terminal equipment receives this line monitoring timing signal, it outputs a monitoring changeover switch signal for T2 = 20 ms as shown in FIG. 3C, and is connected to the relay amplifier board (the disaster prevention receiver board 1 side). And each line on the termination side is switched from the transmission / reception circuit for relay amplification to the line monitoring circuit, and the disconnection and the short circuit of the line are determined.
[0033]
When the line is switched to the disconnection monitoring circuit in the relay amplifier board, a monitoring voltage is output from the lower relay amplifier board to the upper relay amplifier board, and this line monitoring voltage is read from the voltage judgment value in FIG. By reading after T3 = 15 ms as shown in the timing, it is determined whether it is normal, disconnection or short circuit.
[0034]
FIG. 4 is a block diagram of an embodiment of the relay amplification board 7 installed in the tunnel of FIG. In FIG. 4, the relay amplifier board 7 is an embodiment in which each line of the A system line and the B system line is a two-wire system.
[0035]
In the relay amplifier board 7, the A system line 2a and the B system line 2b are connected to the upper side and the lower side, respectively. Corresponding to these A system line 2a and B system line 2b, the relay amplifier board 7 is provided with transmission / reception circuits 14a and 14b for the A system, and transmission / reception circuits 14c and 14d for the B system. . The transmission / reception circuits 14a to 14d include a voltage driver that amplifies the ringing voltage signal in the downstream direction, and a current driver that receives and determines a response current signal and transmits a current signal by the operation of the constant current circuit in the upward direction.
[0036]
Specifically, for the downstream signal (voltage call signal), the transmission / reception circuits 14a and 14c are voltage reception units, and the transmission / reception circuits 14b and 14d are voltage transmission units. For the upstream signal (current response signal), the transmission / reception circuits 14b and 14d are current reception units, and the transmission / reception circuits 14a and 14c are current transmission units.
[0037]
The relay amplifier board 7 is provided with line monitoring circuits 15a and 15b corresponding to the A-system line 2a, and line monitoring circuits 15c and 15d corresponding to the B-system line 2b. For such transmission / reception circuits 14a to 14d and line monitoring circuits 15a to 15d, monitoring switching circuits 16a, 16b, 16c and 16d for switching connection corresponding to the line side are provided.
[0038]
Taking the monitoring switching circuit 16a as an example, two selector switches a1 and a2 are provided corresponding to the + side line and the − side line. The change-over switches a1 and a2 are switched to the line monitoring circuit 15a side for T2 = 20 ms as shown in FIG. 3C by the line monitoring timing signal from the disaster prevention receiving board 1 received by the transmission / reception circuit 14a.
[0039]
The line monitoring timing signal from the disaster prevention receiving board 1 is detected by the transmission / reception circuits 14a and 14c. When the line monitoring timing signal is received, the monitoring changeover switch signal E1 shown in FIG. Output to each of the circuits 16a to 16d.
[0040]
For this reason, when the line monitoring timing signal is received, the changeover switches a1 and a2 of the monitoring changeover circuit 16a, the changeover switches b1 and b2 of the monitoring changeover circuit 16b, the changeover switches c1 and c2 of the monitoring changeover circuit 16c, and the monitoring changeover circuit Each of the 16d selector switches d1 and d2 is switched from the transmitting / receiving circuits 14a to 14d side to the line monitoring circuits 15a to 15d side for T2 = 20 ms.
[0041]
The line monitoring circuits 15a and 15c have a predetermined monitoring voltage for the upper A system line 2a and the upper B system line 2b in a state where the changeover switches a1 and a2 and the changeover switches c1 and c2 are switched to the monitoring side. For example, + 48V is output.
[0042]
On the other hand, the line monitoring circuits 15b and 15d provided on the lower side have a built-in termination resistor Rs. When the changeover switches b1 and b2 and the changeover switches d1 and d2 are switched to the monitoring side, the lower-side A-system line 2a and A termination resistor Rs is connected to each of the B system lines 2b.
[0043]
Thus, when the monitoring timing signal is received, the relay amplifier board 7 outputs a monitoring voltage to the line between the relay amplifier board located on the lower side and the relay amplifier board located on the upper side, A monitoring loop is formed that passes through a terminating resistor provided in the upper relay amplifier board.
[0044]
FIG. 5 shows an equivalent circuit for monitoring that is formed between adjacent relay amplifying boards when a line monitoring timing signal is received. In this equivalent circuit, a monitoring loop of + 48V, Z1, Rs, Z2 and ground is formed between the line monitoring circuit 15a of the lower relay amplifier board 7b and the line monitoring circuit 15b of the upper relay amplifier board 7a.
[0045]
Here, Z1 and Z2 represent circuit impedance components in the line monitoring circuit 15a. For this reason, when the monitoring loop is formed, the main line monitoring circuits 15a and 15b each read a voltage at a predetermined position, for example, a voltage across the termination resistor Rs, and determine normality, disconnection, or short circuit.
[0046]
Under normal conditions, the termination resistor Rs generates a voltage in a predetermined range determined by the voltage divided by the series connection of the monitoring voltage + 48V and circuit impedances Z1 and Z2, and the normality of the line is determined by reading this normal voltage. it can.
[0047]
When the line is disconnected, the voltage across the termination resistor Rs is the power supply voltage + 48V on the line monitoring circuit 15a side. On the other hand, on the line monitoring circuit 15b side, a voltage cannot be obtained from both ends of the termination resistor Rs due to disconnection.
[0048]
Further, when the line is short-circuited, in the line monitoring circuit 15a, the voltage generated by the short-circuit current flowing in the impedance component Z1 is lowered from the power supply voltage + 48V. On the other hand, on the line monitoring circuit 15b side, a very short line voltage is applied due to a short circuit. The formation of the monitoring loop when receiving such a monitoring timing signal is the same for the line monitoring circuits 15c and 15d on the B system side in the relay amplifier board 7.
[0049]
Here, the upper line monitoring circuits 15a and 15c provided in the relay amplifier board 7 detect both disconnection and short circuit. On the other hand, the line monitoring circuits 15b and 15d provided on the lower side do not need to detect disconnection and perform only short circuit detection.
[0050]
When the disconnection of the upper A-system line 2a or B-system line 2b is determined by the line monitoring circuit 15a or the line monitoring circuit 15c provided on both sides, the system mixing circuit 18 provided before the monitoring switching circuits 16a and 16c On the other hand, the switching signal E2a or E2c is output, the mixing switches e1 and e2 are turned on, the normal system line is connected to the disconnected system line, and the voltage calling signal from the normal system line is passed through the system mixing circuit 18 Then, the signal is sent to the line of the system in which the disconnection occurs, and a signal is supplied by loopback to the terminal device connected between the disconnection position.
[0051]
On the other hand, when the line monitoring circuits 15a and 15c detect the short circuit of the lines 2a and 2b, the switching holding signals E3a and E3c are output to the monitoring switching circuits 16a and 16c, and the monitoring side is switched to the monitoring side by the line monitoring timing signal. The change-over switches a1 and a2 or the change-over switches c1 and c2 are held in a switched state, thereby disconnecting the short-circuited line.
[0052]
When a short circuit is detected by the line monitoring circuit 15a or 15c, the short circuit is also detected in the line monitoring circuits 15b and 15d of the relay amplifier panel located adjacent to the upper side, and the line monitoring circuits 15b and 15d are short-circuited. Based on the determination, the switching holding signals E3b and E3d are output to the monitoring switching circuits 16b and 16d, and the switching state of the switching switches b1 and b2 or the switching switches d1 and d3 switched to the monitoring side by the switching holding signals E3b and E3d is maintained. In this way, the shorted line is cut off.
[0053]
Further, the line monitoring circuits 15a to 15d output the operation signals E4a to E4d to the signal synthesizing circuit 20 simultaneously with the short circuit detection, and the signal synthesizing circuit 20 synthesizes the signals of the A system and the B system in the relay amplifier board 7. Make it. By this signal synthesis circuit 20, the communication signal of the fault system separated by the short circuit is diverted to the normal system, and the communication avoiding the short circuit line is enabled.
[0054]
FIG. 6 shows the operation when the disconnection 21 occurs in the A-system line 2a between the relay amplifier boards 7a and 7b.
[0055]
When the line monitoring timing signal from the disaster prevention receiving board 1 is received by each of the relay amplifier boards 7a and 7b, the monitoring changeover switch signal E1 from the transmission / reception circuits 14a and 14c is sent from the OR circuit to each of the monitoring changeover circuits 16a to 16d. Is output and switched to the monitoring side.
[0056]
If a disconnection 21 has occurred in the A-system line 2a between the relay amplifier board 7a and the relay amplifier board 7b at this time, the line monitoring circuit 15a of the relay amplifier board 7b located on the lower side detects the disconnection 21, and the system A switching signal E2a is output to the mixing circuit 18, and the switches e1 and e2 are turned on as shown.
[0057]
When T2 = 20 ms has elapsed since the reception of the line monitoring timing signal, the changeover switches of the monitoring changeover circuits 16a to 16d provided in the relay amplifier boards 7a and 7b return to the transmission / reception circuits 14a to 14d as shown in the figure, and the disaster prevention reception board A normal call signal is sent again from 1, and a response signal is also sent from the terminal side.
[0058]
At this time, the switches e1 and e2 of the system mixing circuit 18 of the relay amplifying board 7b positioned lower than the disconnection 21 are in a loopback state, so that the terminal device positioned on the lower side of the disconnection 21 such as the fire hydrant 4 In response to this, the call signal received from the normal B system line 2b is supplied by loopback to the terminal equipment up to the disconnection 21 through the system mixing circuit 18, and thus the terminal continues even if the disconnection 21 occurs. A normal communication state with the device can be maintained.
[0059]
FIG. 7 shows the operation when a short circuit 22 occurs in the A-system line 2a of the relay amplifier board 7a and the relay amplifier board 7b.
[0060]
When the monitoring switching circuits 16a to 16d are switched to the monitoring side upon reception of the line monitoring timing signal, the short circuit is detected by the line monitoring circuit 15a of the lower relay amplifying board 7b in which the short circuit 22 has occurred, and at the same time located on the upper side. A short circuit is also detected at the same time in the line monitoring circuit 15b of the relay amplifier board 7a.
[0061]
The line monitoring circuit 15a that has detected the short circuit outputs the switching holding signal E3a to the monitoring switching circuit 16a, and even if the monitoring switching switch signal E1 disappears after T2 = 20 ms from the reception of the line monitoring timing signal, the monitoring switching is performed. The changeover switches a1 and a2 of the circuit 16a are maintained in the state of switching on the monitoring side as shown, that is, the state in which the line 2a in which the short circuit 22 has occurred is disconnected from the transmission / reception circuit 16a.
[0062]
At the same time, the line monitoring circuit 15b of the relay amplifier board 7a also outputs a switching holding signal E3b to the monitoring switching circuit 16b, and even if the line monitoring switch signal E1 is cut off, the switching switches b1 and b2 are connected to the monitoring side shown in FIG. The line where the occurrence has occurred is kept disconnected from the transmission / reception circuit 14b.
[0063]
Further, the line monitoring circuit 15a of the relay amplifier board 7b operates by outputting the operation signal E4a to the signal synthesis circuit 20, and synthesizes the A system communication signal and the B system communication signal in the relay amplifier board. At the same time, even in the relay amplifier board 7a, the signal synthesis circuit 20 is activated by the operation signal from the line monitoring circuit 15b, and the A system communication signal and the B system communication signal are synthesized in the relay amplifier board.
[0064]
As a result, for example, the calling signal received by the relay amplifier board 7a from the disaster prevention receiver board is sent to the relay amplifier board 7b through the transmission / reception circuit 14a, the signal synthesis circuit 20, and the transmission / reception circuit 14d by the B system line 2b, 7b, the signal is transmitted to the lower A-system line 2a through the transmission / reception circuit 14c, the signal synthesis circuit 20, and the transmission / reception circuit 14b. That is, the backup amplifiers 7a and 7b before and after the short circuit 22 disconnect the line causing the short circuit 22, and at the same time, perform a backup operation to bypass the A system communication signal with respect to the normal B system line 2b.
[0065]
Further, in a backup state in which loopback is performed for a disconnection as shown in FIG. 6 or a backup operation state in which a short-circuit line is bypassed in response to a short circuit in FIG. 7, the normal communication state is automatically restored when the disconnection 21 or the short circuit 22 is resolved. can do.
[0066]
For example, when the disconnection 21 is restored by repair or the like in FIG. 6, when the line monitoring timing signal is received from the disaster prevention receiving board 1 for the first time after the restoration, the line monitoring circuit 15a of the relay amplifier board 7b determines that the line is normal. The operation signal E2a that has been output to the system mixing circuit 18 is stopped, and the switches e1 and e2 of the system mixing circuit 18 are turned off to automatically cancel the loopback state and restore the normal communication state. Can do.
[0067]
When the short circuit 22 is restored by repair or the like in the short circuit state of FIG. 7, when the line monitoring timing signal is received for the first time from the restoration, the line monitoring circuit 15a and the relay amplifier board 7a of the relay amplifier board 7b that has detected the short circuit. It is determined that the line is normal in each of the line monitoring circuits 15b, and the changeover holding signals E3a and E3b are stopped, and the changeover switches a1 and a2 and b1 and b2 of the monitoring changeover circuits 16a and 16b in the disconnected state. Return to the transmission / reception circuit side, and at the same time, the operation signals E4a and E4b are stopped and the synthesis operation of the signal synthesis circuit 20 is stopped, whereby the normal communication operation can be automatically restored.
[0068]
Furthermore, in the relay amplifier board 7 in the present invention shown in FIG. 4, each of the transmission / reception circuits 14a to 14d determines an overcurrent during communication. When the transmission / reception circuits 14a to 14d determine an overcurrent during communication, the disconnection signals E5a to E5d are output to the respective monitoring switching circuits 16a to 16d, and the line side on which the overcurrent is detected is disconnected. At the same time, an operation signal (not shown) is output to the signal synthesis circuit 20.
[0069]
As a result, when an overcurrent is detected during communication, the line causing the overcurrent is disconnected in the same manner as when the short circuit 22 is detected at the line monitoring timing shown in FIG. A backup operation is performed to divert the fault system signal to the system line. Also for the backup operation by the overcurrent detection by the transmission / reception circuits 14a to 14d, the normal communication state can be automatically restored when the overcurrent state is eliminated.
[0070]
FIG. 8 is a block diagram of the disaster prevention receiving board 1 when the transmission line of the present invention is a four-wire system. In the case of the four-wire system, for example, the transmission path from the uplink tunnel transmission control unit 9a is configured by two systems of an A-system transmission path 30a and a B-system transmission path 30b. The system downstream line 31 and the system A upstream line 32 are configured, and the system B transmission line 30 b is configured by a system B downstream line 33 and a system B upstream line 34.
[0071]
A voltage paging signal is transmitted from the disaster prevention receiving board 1 to the A-system downlink 31 and the B-system downlink 33 in the voltage mode. A current mode current response signal is transmitted from the terminal device to the A-system uplink 32 and the B-system uplink 34. In this case, one of the A system and the B system is used as a priority line, the priority system is used for normal communication, and the other system is used as a backup system in case of disconnection or short circuit.
[0072]
In this case, since the upper four lines and the lower four lines are connected as the relay amplifier 7, the same circuits as the upper lines in FIG. For these four lines, the same circuit as each line on the lower side in FIG. 7 may be provided.
[0073]
This is the same for the downlink tunnel transmission control unit 9b, which is composed of two systems, an A-system transmission line 40a and a B-system transmission line 40b. Further, the A-system transmission line 40a includes an A-system transmission line 41 and The B system transmission line 40 b is configured by a B system downstream line 43 and a B system upstream line 44.
[0074]
As for the normal call response from the disaster prevention receiving board 1 in the above embodiment, information exchange by polling that sequentially designates terminal devices is taken as an example, but any response on the disaster prevention receiving board 1 side and terminal device side is taken as an example. Of course, information may be communicated in an interrupted manner when an event occurs.
[0075]
Furthermore, the present invention includes appropriate modifications that do not impair the objects and advantages thereof, and the present invention is not limited by the numerical values shown in the above embodiments.
[0076]
【The invention's effect】
As described above, according to the present invention, when a disconnection or a short circuit of a line is detected by a relay amplifier board, communication of a normal call response between the disaster prevention receiving board and the terminal device is temporarily stopped. In the meantime, a termination resistor is connected to the upper side of the line by a relay amplifier board, and a monitoring voltage is applied from the lower side to determine the disconnection or short circuit of the line, and the disconnection or short circuit in a stable state where no communication signal exists on the line Therefore, it is possible to accurately determine whether the wire is disconnected or short-circuited according to the line voltage, and a more reliable backup can be performed.
[0077]
In addition, since it is not necessary to monitor the normal communication state for the determination of disconnection and short circuit, the state of the line can be determined in a short time.
[0078]
In addition, when a failure is resolved after a line break or short circuit is detected and a backup operation is performed, the normal communication state can be automatically restored, and maintenance is easy because no human recovery operation is required. It is.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of the equipment configuration of the present invention.
FIG. 2 is a block diagram of the disaster prevention reception board of FIG.
FIG. 3 is a timing chart of the monitoring operation of the present invention.
4 is a block diagram of the relay amplifier panel of FIG.
FIG. 5 is an equivalent circuit diagram of a line monitoring loop formed between repeaters at a monitoring timing.
FIG. 6 is an operation explanatory diagram when the line is disconnected.
FIG. 7 is an operation explanatory diagram when the line is short-circuited.
FIG. 8 is a block diagram of the disaster prevention reception board in the case of a 4-wire system.
[Explanation of symbols]
1: Disaster prevention reception board
2, 3: Transmission path
2a, 3a: A line
2b, 3b: B system line
4: Fire hydrant
5: Automatic valve device
6: Detector
7, 7a-7n: Relay amplifier board
8: MPU
9a: Transmission control unit for upstream tunnel
9b: Downstream tunnel transmission control unit
10: Display operation unit
11: Transfer department
12: Call response part
13: Monitoring timing setting unit
14a-14d: Transmission / reception circuit
15a to 15d: Line monitoring circuit
16a to 16d: monitoring switching circuit
17: OR circuit
18: System mixing circuit
20: Signal synthesis circuit
21: Disconnection
22: Short circuit
100A: Up tunnel
100B: Down tunnel

Claims

Tunnel to connect the relay amplification Release at predetermined intervals with connecting two systems terminal equipment such as detectors and control devices installed in the tunnel to co simultaneously sends a signal to the transmission path of the drawn from disaster received Release In the tunnel disaster prevention equipment that monitors and controls the inside,
In the disaster prevention receiving board, a monitoring timing setting unit is provided to stop the monitoring process every predetermined time and transmit a line monitoring timing signal,
When the line monitoring timing signal is received by the relay amplifier board, the upper line and the lower line are switched from the transmission / reception side to the monitoring side to monitor the state of the line, and when a line abnormality is detected, backup is performed. A line abnormality monitoring unit that switches to a state is provided,
The line abnormality monitoring unit of the relay amplifier panel is
A monitoring switching circuit for switching each of the upper line and the lower line between the transmission and reception side and the monitoring side;
A system mixed circuit that connects the two lines on the upper side,
A signal synthesis circuit that synthesizes communication signals of each system between two systems of transmission / reception units;
When the line monitoring timing signal is received from the disaster prevention receiving board, the monitoring switching circuit is switched to the monitoring side for a certain period of time to monitor the upper line, and when the disconnection of the line is detected, When the two lines are connected by operation and looped back to the line that disconnected the normal system signal, and the short circuit of the line is detected, the monitoring switching circuit is maintained in the switching state on the monitoring side and the shorted line A line monitoring circuit that operates the signal synthesis circuit and bypasses the short-circuited location by synthesizing communication signals between the transmission and reception units, and
Tunnel disaster prevention facility, characterized in that it comprises a.

The tunnel disaster prevention facility according to claim 1 , wherein the line monitoring circuit restores the mixed system circuit when the disconnection of the line is not detected after the detection, and the short circuit is not detected after the detection. A tunnel disaster prevention facility characterized by restoring a monitoring switching circuit and a signal synthesis circuit.

2. The tunnel disaster prevention facility according to claim 1 , wherein when the overcurrent is detected during communication, the transmission / reception circuit of the relay amplifier panel switches the monitoring switching circuit to a monitoring side to disconnect the line where the overcurrent is detected. In addition, a tunnel disaster prevention facility characterized in that the signal synthesizing circuit is operated to bypass a line in which an overcurrent is detected by synthesizing communication signals of each system.

4. The tunnel disaster prevention equipment according to claim 3 , wherein the transmission / reception circuit restores the monitoring switching circuit and the signal synthesis circuit when an overcurrent is not detected after detection.