BE536888A

BE536888A -

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Publication number: BE536888A
Authority: BE

Description

       

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   La présente invention concerne des perfectionnements relatifs aux dispositifs de vérification de circuits électriques, et plus particuliè- rement aux dispositifs de ce genre utilisés avec les appareillages de frei- nage électro-pneumatiques des trains de chemin de fer pour signaler l'inté- grité ou le manque d'intégrité des circuits de commande ou d'autres appa- reils électriques associés à ces circuits. 



   La présente invention constitue un perfectionnement des dispo- sitifs analogues décrits dans la demande de brevet déposée aux Etats-Unis d'Amérique le 18 Juillet 1952 pour "Equipement de vérification de circuits électriques". 



   Il y a déjà quelque temps qu'on désire indiquer d'une manière continue l'intégrité ou le manque d'intégrité des circuits électriques de commande et des enroulements de valves magnétiques dans les appareillages électro-pneumatiques de commande de freinage utilisés sur les trains de che-   mins de fer ; a proposé et utilisé dans ce but différents dispositifs et   procédés. Cependant, les dispositifs déjà connus de ce genre sont notable- ment plus compliqués que celui faisant l'objet de la présente invention, comme on le verra clairement un peu plus loin. 



   Le dispositif conforme à la présente invention exerce une véri-   fication   positive, car il coupe la source du courant de vérification sur la locomotive quand un défaut se produit dans un circuit de commande quelcon- que. Ce dispositif fournit également une indication d'intégrité à l'extré- mité arrière du train, sans utiliser des fils conducteurs supplémentaires s'étendant tout le long du train et avec un équipement minimum de relais sur le dernier wagon. 



   La présente invention a pour but principal de réaliser un dispo- sitif nouveau et perfectionné de vérification de circuit. 



   L'invention se propose aussi de réaliser un circuit nouveau et perfectionné de vérification d'intégrité. 



   Dans ce circuit de vérification, un courant alternatif de véri- fication peut être superposé à un courant continu utilisé dans un but de commande, et les mêmes conducteurs sont utilisés pour les courants de com- mande et de vérification. Les indications des conditions du circuit affec- tant l'intégrité sont fournies en plusieurs endroits avec un équipement minimum. Le circuit conforme à l'invention offre la protection maxima oon- tre les défaillances du dispositif proprement dit de vérification. 



   D'autres buts de l'invention apparaîtront en étudiant la descrip- tion qui va suivre d'un mode de réalisation particulier de l'invention; au cours de cette description; on se référera au dessin annexé sur lequel : - la figure 1 est un schéma des circuits d'un mode de réalisation de l'invention. 



   - et la figure 2 représente une variante d'une partie des circuits de la figure 1. 



   DESCRIPTION (figure 1). 



   Pour bien montrer la nature et l'utilité de la présente invention, on a représenté sur la figure 1 un mode de réalisation associé à un appa- reillage simplifié de commande de freinage comprenant une source de courant continu, telle qu'une batterie 1, et un maître-contrôleur électro-pneumati- que 2 d'une conception convenable et usuelle quelconque, par exemple un maî- tre-contrôleur tel que celui décrit dans le brevet des Etats-Unis   d'Améri-   que N  2.068.345 du 19 Janvier 1937. On trouvera dans ce brevet une expli- 

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 cation détaillée de ce maître-contrôleur. 



   Alors que le train peut comprendre évidemment un nombre quelcon- que de wagons, on a cependant représenté sur le dessin un train de deux   wa-   gons seulement pour plus de simplicité. Les valves magnétiques de desser- rage de la locomotive, du wagon intermédiaire et du dernier wagon, sont dé- signées respectivement par les nombres de référence 3, 4 et 5, tandis que les valves magnétiques de serrage sont désignées respectivement par 6, 7 et 8. Il est bien entendu que tous les autres wagons intermédiaires d'un train sont équipés d'une manière analogue, mais il n'est pas indispensable de re- présenter tous ces wagons pour faire comprendre l'invention. Sur le dessin, la locomotive et le dernier wagon du train sont séparés du wagon intermédiai- re par les lignes x-x et x'-x'.

   L'appareillage de commande de freinage com- prend aussi un câble 9 d'alimentation sur la locomotive seulement, un câble de commande de serrage 10, un câble de commande de desserrage 11 et un câ- ble commun de retour 12, ces trois derniers câbles s'étendant depuis la lo-   comotive tout le long du train jusqu'au dernier wagon ; descontacts A et R   du   maître-contrôleur   2 déjà mentionné commandant respectivement l'arrivée du courant dans les câbles 10 et 11. 



   Comme on l'expliquera plus loin d'une manière détaillée, la véri- fication d'intégrité est réalisée en produisant sur la locomotive un courant alternatif d'une fréquence appropriée égale par exemple à 3.000 cycles par seconde, en transmettant ce courant alternatif jusqu'à l'extrémité du train, puis en le faisant revenir à la locomotive, un dispositif de signalisation lumineuse fournissant les indications d'intégrité. Les signaux lumineux de ce dispositif sont commandés par des relais excités par un courant continu obtenu sur la locomotive et le dernier wagon en redressant une partie du courant alternatif. 



   Pour atteindre ce but, on utilise un générateur de courant alter- natif qui peut être constitué par un tube oscillateur d'un type commercial, tel que celui représenté dans la demande de brevet américain citée plus haut. Ce générateur, désigné dans son ensemble par le nombre de référence 13, est d'un modèle convenable quelconque et se trouve installé sur la lo- comotive. Dans ce qui va suivre, on désignera la locomotive par   l'expres-   sion "première station".

   Le générateur 13 peut être alimenté par la batte- rie 1 au moyen d'un circuit passant par le conducteur d'alimentation 9, un conducteur 14, un conducteur 15 situé à l'intérieur du contrôleur 2 un con- ducteur 16, un fusible 17, un conducteur 18, un contact 19 appartenant à un commutateur tripolaire à deux positions désigné dans son ensemble par 20, un conducteur 21, le générateur 13 lui-même, un conducteur 22 et le conduc- teur commun de retour 12 aboutissant à la batterie 1. Le commutateur 20 est commandé à la main; il comprend des contacts supplémentaires 23 et 24, qui sont utilisés quand la locomotive est à l'arrière, comme on le verra mieux un peu plus loin, les deux contacts 23 et 24 sont connectés au conduc- teur 18.

   Des condensateurs 25 et 26 sont connectés respectivement en sé- rie avec les contacts 23 et 24, dans le but de supprimer les arcs de ruptu- re. Le contact 23 est connecté en parallèle sur le contact R de desserrage du contrôleur électro-pneumatique 2, au moyen d'un circuit passant par le conducteur 16, le dusible 17, le conducteur 18, le conducteur 27, le con- tact 23, le condensateur 25 et le conducteur 28. Le contact 24 est connec- té en parallèle sur le contact de serrage A du contrôleur 2, au moyen d'un circuit passant par le conducteur 15, le conducteur 16, le fusible 17, le conducteur 18, le conducteur 29, le contact 24, le condensateur 26 et le conducteur 30. 



   La sortie du générateur 13 est appliquée aux conducteurs 31 et 32. 



  Si le générateur 13 est un tube oscillateur ordinaire, les conducteurs 31 et 

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32 sont connectés aux bornes du circuit de plaque de ce tube. Comme on le voit sur le dessin, le conducteur 31 est connecté   à   une borne du primai- re 33 d'un transformateur désigné dans son ensemble par le nombrede réfé- rence 34. Le conducteur de sortie 32 du générateur 13 est connecté à l'au- tre borne du primaire 33 au moyen de deux circuits de commutation en paral- lèle ; l'un de ces circuits comprend un interrupteur manuel 35 de remise en position initiale, et l'autre circuit comprend un contact 36   d'umrelais   37 comportant un enroulement 37a prévu dans un but qui apparaîtra un peu plus loin.

   Une extrémité du secondaire 38 du transformateur 34 est connectée par un conducteur 39 au contact A.du contrôleur 2, tandis que l'autre extré- mité du secondaire 38, qui a une faible impédance de sortie, est connectée au conducteur de commande de serrage 10 déjà mentionné. 



   Le contact R du contrôleur 2 est connecté par un conducteur 40 à une borne du primaire 41 d'un transformateur désigné dans son ensemble par le nombre de référence   42,   l'autre borne de ce primaire étant connectée au conducteur de commande de desserrage 11. Le secondaire 43 du transforma- teur 42 est connecté à un redresseur d'onde entière 44 d'un type convenable quelconque, et la sortie du redresseur 44 excite l'enroulement 45a d'un relais 45 comportant un contact 46 normalement ouvert. Quand le contact 46 est fermé, il connecte le conducteur 21 à une borne de l'enroulement de re- lais 37a par un conducteur 47, l'autre borne de cet enroulement étant con- nectée par un conducteur 48 et un conducteur 22 au conducteur commun de re- tour 12.

   Un condensateur 49 et une résistance 50 disposés en série l'un par rapport à l'autre et servant à retarder la chute du relais 37 sont con-   nectés   en parallèle avec l'enroulement 37a de ce relais. En plus du con- tact 36 déjà mentionné, le relais 37 comporte un contact travail 51 et un contact 52 repos et travail. Quand le contact 51 est fermé, il complète un circuit pour exciter une valve magnétique 53; ce circuit passe par la batterie 1, le conducteur d'alimentation 9, le conducteur   54,   le contact fermé 51, le conducteur 55, le conducteur 56, la valve magnétique 53, le conducteur 57, le conducteur 22 et le conducteur de retour 12 aboutissant à la batterie. Cette valve magnétique 53 a été prévue dans un but que l'on expliquera ultérieurement. 



   Un interrupteur pneumatique 58 est connecté en parallèle avec le contact 51 du relais 37. Cet interrupteur pneumatique 58 peut être action- né par la pression régnant dans une conduite qui relie la valve de freinage (non représentée) au maître-contrôleur 2 ; les contacts de l'interrupteur pneumatique sont disposés de manière à être normalement maintenus fermés par un ressort 58a et à pouvoir s'ouvrir quand une pression d'une valeur faible prédéterminée est établie dans la conduite mentionnée ci-dessous, et cela dans un but que l'on expliquera plus loin. 



   Le contact 52 est connecté au conducteur 21 à potentiel positif par un conducteur 59 de telle manière que, quand le contact 52 se trouve dans sa position de travail et de fermeture, un circuit s'établit par une lampe blanche indicatrice 60, le conducteur 22 puis le conducteur de re- tour 12 à potentiel négatif, et quand le contact 52 se trouve dans sa posi- tion de repos et de fermeture, un circuit s'établit par une lampe rouge indicatrice 61, le conducteur 22 et le conducteur de retour 12. 



   Sur le dernier wagon du train, wagon qu'on désignera ici par l'ex- pression "deuxième station", on prévoit un circuit d'indication sensible- ment analogue à celui de la locomotive. Un commutateur manuel tripolaire et à deux positions, désigné dans son ensemble par le nombre de référence 62, comporte des contacts 63, 64 et 65 susceptibles, quand le commutateur est fermé, de compléter des circuits passant respectivement par les conduc- teurs 12,10 et 11.

   Le contact 63 est connecté par un conducteur 80 à une 

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 borne d'entrée d'un redresseur d'onde entière 66 d'un type approprié quel- conque; l'autre borne d'entrée de ce redresseur est connectée par un   conden-   sateur de blocage 67 au contact 64, ainsi qu'à un contact 68 d'un relais détecteur 69, dont l'enroulement 69a est connecté aux bornes de sortie du redresseur 66 de manière à être excité par celui-ci. Le contact 68 du re- lais 69 est connecté par un condensateur de blocage 70 au contact 65 du com- mutateur 62. Le relais 69 comporte également un contact 71 travail et re- pos.

   Ce contact 71 est connecté à une batterie locale et séparée 72 (telle que la batterie du wagon), par un conducteur 73; quand le contact 71 est dans sa position de fermeture travail, une lampe blanche de signalisation 74 est excitée par les conducteurs 75 et 76, et quand le contact 71 est dans sa position de fermeture repos, une lampe rouge d'avertissement 77 est excitée par les conducteurs 78, 79 et 76. 



    FONCTIONNEMENT.-   
Quand le dispositif indicateur d'intégrité est au repos, les deux relais 45 et 69 sont normalement-non excités. Quand on veut utiliser le dispositif indicateur, on ferme d'abord les commutateurs manuels 20 et 62 disposés respectivement sur la locomotive et le dernier wagon ; si aucun défaut n'existe dans les circuits de commande de freinage comprenant les conducteurs de commande 9, 10, 11 et 12, les relais 45 et 69, comportant les enroulements 45a et 69a, peuvent être excités en appuyant à la main sur l'interrupteur 35 prévu sur la locomotive pour la remise en position initiale. On ferme ainsi le circuit primaire du transformateur 34 et on applique ainsi le courant alternatif à 3.000 cycles de son secondaire 38 au conducteur de serrage 10 s'étendant tout le long du train.

   Ce courant passe par le contact 64, le condensateur 67, le redresseur d'onde entière 66 du dernier wagon, puis retourne à la locomotive par le conducteur 80, le contact 63, le conducteur de retour de batterie 12, traverse la batterie d'alimentation 1, le conducteur 9, le conducteur 14, le conducteur 15 du maître-contr8leur 2, le conducteur 16, le fusible 17, le conducteur 18, le conducteur 29, le circuit de suppression d'arc de rupture comprenant le contact 24, le condensateur 26, le conducteur 30 et le conducteur 39, et enfin ferme le circuit en arrivant dans le secondaire 38 du transformateur 34. Le redresseur d'onde entière 66 du dernier wagon se trouve excité et fournit par conséquent du courant continu au relais 69 par les conducteurs 81 et 82, en excitant ainsi le relais 69 et en fermant le circuit à travers le contact 68 et le contact 71 dans sa position de travail.

   Le contact 71 dans sa position de fermeture travail produit l'excitation et l'allumage de la lampe blanche indicatrice 74. La fermeture du contact 68 du relais 69 connecte le conducteur de serrage 10, dans lequel circule le courant alternatif à 3.000 cycles, au conducteur de commande de desserrage 11, par un circuit passant par le contact 64, le condensateur   67,   le conducteur 83, le contact 68, le conducteur 84, le condensateur 70, le contact 65, le con- ducteur 11, le primaire 41 du transformateur 42, le câble   40,   le conducteur 28, le condensateur 25, le contact 23, le conducteur 27, le conducteur 18, le conducteur 29, le contact 24, le condensateur 26, le conducteur 30 et le conducteur 39 aboutissant au secondaire 38 du transformateur 34.

   Le secondaire 43 du   t@ansformateur   42 fournit alors un courant alternatif au redresseur 44 par les conducteurs 85 et 86; la sortie de ce redresseur ex- cite l'enroulement 45a du relais   45,   afin de fermer le contact 46 et de fai- re arriver ainsi le courant continu de la batterie 1 dans le relais répéti- teur 37 comportant l'enroulement 37a. Le relais répétiteur 37 s'excite et ferme par conséquent les contacts 36 et 51, ainsi que le contact 52 dans sa position de fermeture travail.

   En se fermant, le contact 36 court-circui- te l'interrupteur manuel 35 de remise en position initiale, par l'intermédiai- re des conducteurs 87 et 88, et maintient excité le circuit primaire du trans- 

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 formateur 34 jusqu'à ce qu'un défaut soit indiqué dans les circuits de com- mande de freinage ou jusqu'à ce que les commutateurs 20 et/ou 62 soient ouverts à la main. Le condensateur 49 et la résistance 50 établissent un retard dans la chute du relais 37 après la coupure du circuit d'excitation de ce relais, de telle sorte que des coupures momentanées de l'ordre de quelques secondes dans le circuit d'excitation ne produisent pas la ruptu- re d'excitation du relais 37. 



   La fermeture du contact 51 du relais 37 établit.un courant pour exciter une valve magnétique 53, qui fonctionne avec les freins pneumati- ques pour effectuer une application de ceux-ci, si le mécanicien tente une application électropneumatique des freins quand l'équipement présente des défauts dans ses circuits de commande. 



   La valve magnétique 53 est analogue au point de vue fonctionne- ment à celle décrite dans les brevets des   Etats-Unis   d'Amérique n  2. 573.442 du 30 Octobre 1951 et 2.605.329 du 29 Juillet 1952. On peut se référer à ces brevets pour mieux comprendre le fonctionnement de la valve 53 et son rôle dans une installation de freinage. 



   La fermeture du contact 52 du relais répétiteur 37 provoque l'allumage de la lampe blanche de signalisation 60 indiquant que les cir- cuits sont en état de fonctionnement. Quand la lampe 60 s'est allumée, l'opérateur peut lâcher l'interrupteur 35, qui revient à sa position d'ou- verture sous l'action d'un ressort non représenté. Dans le cas où le con- ducteur de serrage 10 s'étendant tout le long du train est défaillant, les deux relais détecteurs   45   et 69 comportant respectivement les enroulements 
45a et 69a perdent leur excitation et provoquent l'allumage des lampes 61 et 77.

   Le relais 69 ouvre son contact 68 en supprimant ainsi l'excitation des relais   45   et 37 montés sur la locomotive, comme on peut le voir en con- sidérant les circuits respectifs d'excitation de ces relais; il en résulte que la connexion est coupée entre le générateur 13 et le transformateur 34. 



  Quand le défaut a été réparé, il faut manoeuvrer l'interrupteur manuel 35 de remise en position initiale pour que les lampes rouges 61 et 77 s'étei- gnent . 



   On voit par conséquent qu'une défaillance du circuit de commande de desserrage comprenant le conducteur 11 supprime aussi l'excitation du relais détecteur   45,   qui supprime à son tour   l'excitation   du relais répéti- teur 37 et qui ouvre le circuit primaire du transformateur 34 pour couper l'alimentation du conducteur de serrage 10 en courant alternatif et pour supprimer par conséquent l'excitation du relais répétiteur   69.   Le relais détecteur 37 de la locomotive et le relais détecteur 69 du dernier wagon n'étant plus excités, les lampes rouges 61 et 77 aux deux extrémités du train sont allumées et indiquent des circuits défectueux. 



   Une coupure dans le conducteur de retour 12 ouvrirait le secondaire 38 du transformateur 34 et supprimerait ainsi l'alimentation'du conducteur de serrage 10 en courant alternatif ; il en résulterait la suppression de l'excitation des relais détecteurs 37 et 69, ce qui produirait l'éclairage des lampes rouges 61 et 77 pour indiquer un tel défaut. 



   Il faut insister ici sur le fait que, pour tous les défauts sup- posés et mentionnés plus haut, en même temps que le relais 37 perd son ex- citation et que la lampe rouge 61 s'allume, l'ouverture du contact 36 du relais 37 provoque l'ouverture du primaire 33 du transformateur 34 et indi- que ainsi nettement l'existence d'un défaut en supprimant complètement le courant indicateur d'intégrité à travers les circuits de vérification. 



   Un commutateur manuel supplémentaire 89 peut être inclus dans ce dispositif, comme on le voit dans le mode de réalisation représenté sur 

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 la figure 2, dans le but de commander les freins à partir de l'arrière du train. Ceci peut être réalisé en connectant un conducteur 90 au conducteur 9 &'alimentation sur la locomotive et en faisant courir ce câble tout le long du train jusqu'au wagon arrière où le commutateur 89,comprenant deux contacts 91 et 92, peut   (par =,-moyen   non représenté) connecter par ces con- tacts le conducteur 9 respectivement au conducteur de serrage 10 et au con- ducteur de desserrage 11, quand on désire serrer les freins. 



   Le fonctionnement du   maître-contrôleur   2 ou celui du commutateur 89, en vue de commander les freins, ne shunte pas le passage du courant al- ternatif de vérification à travers les circuits de commande de freinage et ne provoque pas ainsi une indication de défaut, parce que la bobine d'in- ductance 93 empêche un courant alternatif quelconque de vérification de pas- ser à travers le conducteur d'alimentation 9 ou le conducteur 90 (figure 2) pendant une application des freins. Les condensateurs 67 et 70 empêchent le courant continu passant dans les circuits de commande de freinage de gêner le fonctionnement correct de l'équipement de vérification de l'extré- mité arrière dans le cas où un défaut se produit dans les circuits de com- mande. 



   Dans le mode de réalisation représenté sur la figure 2, les cir- cuits représentés et les nombres de référence utilisés sont identiques à ceux de la figure l, à l'exception de l'addition des circuits supplémentai- res de commutation et d'une modification du dispositif d'allumage des lam- pes 74 et 79. Le dispositif modifié servant à allumer les lampes d'aver- tissement à l'arrière du train comprend un conducteur d'alimentation de si- gnal 94, branché sur le conducteur 90, et un conducteur de retour de signal   95 aboutissant au conducteur de retour 12 ; onélimine ainsi la nécessité   d'utiliser la batterie locale 72 et les conducteurs partant de cette batte- rie, comme dans le cas de la figure 1.

   Dans cette variante, une coupure dans le conducteur d'alimentation 9 ou dans le conducteur 90 est indiquée par l'absence de tout signal indicateur à l'arrière du train. 



   Bien que   1 on   n'ait décrit et représenté que deux modes de réa- lisation de l'invention, il est bien entendu qu'on peut apporter aux dis- positifs décrits des modifications variées sans sortir pour cela du domai- ne de l'invention. 



    REVENDICATIONS..   



   1. - Dispositif de vérification de circuits électriques de com- mande caractérisé par le fait qu'il est destiné à vérifier un circuit de commande et qu'il comprend en combinaison un tube oscillateur électronique, comportant un circuit d'alimentation de plaque associé audit circuit de com- mande pour produire un courant de vérification d'intégrité à haute fréquen- ce à travers ledit circuit pendant le fonctionnement du tube, et un relais sensible à l'interruption du passage du courant de vérification à travers ledit circuit de commande pour ouvrir ledit circuit d'alimentation de pla- que.



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   The present invention relates to improvements relating to devices for checking electrical circuits, and more particularly to devices of this type used with the electro-pneumatic braking equipment of railway trains to indicate the integrity or lack of integrity of control circuits or other electrical apparatus associated with those circuits.



   The present invention constitutes an improvement of the analogous devices described in the patent application filed in the United States of America on July 18, 1952 for "Equipment for checking electrical circuits".



   There has been a desire for some time to continuously indicate the integrity or lack of integrity of electrical control circuits and magnetic valve windings in electro-pneumatic brake control equipment used on trains. of railroads; has proposed and used various devices and methods for this purpose. However, the devices already known of this type are notably more complicated than that forming the subject of the present invention, as will be clearly seen a little further on.



   The device according to the present invention exerts a positive check because it cuts off the source of the check current to the locomotive when a fault occurs in any control circuit. This device also provides an indication of integrity at the rear end of the train, without the use of additional lead wires running the length of the train and with minimal relay equipment on the last car.



   The main object of the present invention is to provide a new and improved circuit verification device.



   The invention also proposes to provide a new and improved integrity verification circuit.



   In this test circuit, an AC test current can be superimposed on a DC current used for control purposes, and the same conductors are used for the control and test currents. Indications of circuit conditions affecting integrity are provided in several places with minimal equipment. The circuit according to the invention offers maximum protection against failures of the verifying device itself.



   Other objects of the invention will become apparent on studying the description which follows of a particular embodiment of the invention; during this description; reference will be made to the appended drawing in which: FIG. 1 is a circuit diagram of one embodiment of the invention.



   - and Figure 2 shows a variant of part of the circuits of Figure 1.



   DESCRIPTION (figure 1).



   To clearly show the nature and the utility of the present invention, there is shown in FIG. 1 an embodiment associated with a simplified braking control device comprising a direct current source, such as a battery 1, and an electro-pneumatic master controller 2 of any suitable and customary design, for example a master controller such as that described in United States Patent No. 2,068,345 of 19 January 1937. This patent explains

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 detailed cation of this master controller.



   While the train can obviously comprise any number of wagons, however, a train of two wagons only has been shown in the drawing for the sake of simplicity. The magnetic release valves of the locomotive, the intermediate wagon and the last wagon are denoted by the reference numbers 3, 4 and 5 respectively, while the magnetic clamping valves are denoted respectively by 6, 7 and 8. It is understood that all the other intermediate wagons of a train are equipped in a similar manner, but it is not essential to represent all these wagons in order to understand the invention. In the drawing, the locomotive and the last car of the train are separated from the intermediate car by lines x-x and x'-x '.

   The brake control gear also comprises a power cable 9 on the locomotive only, a tightening control cable 10, a release control cable 11 and a common return cable 12, the latter three cables extending from the locomotive all the way down the train to the last car; contacts A and R of the already mentioned master controller 2 respectively controlling the arrival of current in cables 10 and 11.



   As will be explained in more detail later, the integrity check is carried out by producing on the locomotive an alternating current of a suitable frequency equal for example to 3,000 cycles per second, by transmitting this alternating current up to 'at the end of the train, then returning it to the locomotive, a light signaling device providing the integrity indications. The light signals of this device are controlled by relays excited by a direct current obtained on the locomotive and the last wagon by rectifying part of the alternating current.



   To achieve this aim, an alternating current generator is used which can be constituted by an oscillator tube of a commercial type, such as that shown in the US patent application cited above. This generator, designated as a whole by the reference number 13, is of any suitable model and is installed on the locomotive. In what follows, the locomotive will be designated by the expression "first station".

   The generator 13 can be supplied by the battery 1 by means of a circuit passing through the supply conductor 9, a conductor 14, a conductor 15 located inside the controller 2 a conductor 16, a fuse 17, a conductor 18, a contact 19 belonging to a three-pole switch with two positions designated as a whole by 20, a conductor 21, the generator 13 itself, a conductor 22 and the common return conductor 12 terminating in the battery 1. Switch 20 is manually operated; it includes additional contacts 23 and 24, which are used when the locomotive is at the rear, as will be seen better a little further on, the two contacts 23 and 24 are connected to conductor 18.

   Capacitors 25 and 26 are respectively connected in series with contacts 23 and 24, for the purpose of suppressing breaking arcs. The contact 23 is connected in parallel to the release contact R of the electro-pneumatic controller 2, by means of a circuit passing through the conductor 16, the lead 17, the conductor 18, the conductor 27, the contact 23, capacitor 25 and conductor 28. Contact 24 is connected in parallel with clamping contact A of controller 2, by means of a circuit passing through conductor 15, conductor 16, fuse 17, conductor 18 , conductor 29, contact 24, capacitor 26 and conductor 30.



   The output of generator 13 is applied to conductors 31 and 32.



  If the generator 13 is an ordinary oscillator tube, the conductors 31 and

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32 are connected to the plate circuit terminals of this tube. As can be seen in the drawing, the conductor 31 is connected to a terminal of the primary 33 of a transformer designated as a whole by the reference number 34. The output conductor 32 of the generator 13 is connected to the transformer. other primary terminal 33 by means of two parallel switching circuits; one of these circuits comprises a manual reset switch 35, and the other circuit comprises a contact 36 of a relay 37 comprising a winding 37a provided for a purpose which will appear a little later.

   One end of secondary 38 of transformer 34 is connected by conductor 39 to contact A of controller 2, while the other end of secondary 38, which has low output impedance, is connected to clamp control conductor. 10 already mentioned.



   The R contact of the controller 2 is connected by a conductor 40 to one terminal of the primary 41 of a transformer designated as a whole by the reference number 42, the other terminal of this primary being connected to the release control conductor 11. Secondary 43 of transformer 42 is connected to a full wave rectifier 44 of any suitable type, and the output of rectifier 44 energizes winding 45a of a relay 45 having a normally open contact 46. When the contact 46 is closed, it connects the conductor 21 to one terminal of the relay winding 37a by a conductor 47, the other terminal of this winding being connected by a conductor 48 and a conductor 22 to the conductor. common return 12.

   A capacitor 49 and a resistor 50 arranged in series with respect to each other and serving to delay the fall of the relay 37 are connected in parallel with the winding 37a of this relay. In addition to the contact 36 already mentioned, the relay 37 comprises a work contact 51 and a contact 52 rest and work. When the contact 51 is closed, it completes a circuit for energizing a magnetic valve 53; this circuit passes through battery 1, supply conductor 9, conductor 54, closed contact 51, conductor 55, conductor 56, magnetic valve 53, conductor 57, conductor 22 and return conductor 12 resulting in the battery. This magnetic valve 53 was provided for a purpose which will be explained later.



   A pneumatic switch 58 is connected in parallel with the contact 51 of relay 37. This pneumatic switch 58 can be actuated by the pressure prevailing in a pipe which connects the brake valve (not shown) to the master controller 2; the contacts of the pneumatic switch are arranged so as to be normally kept closed by a spring 58a and to be able to open when a pressure of a predetermined low value is established in the pipe mentioned below, and this for a purpose which will be explained later.



   The contact 52 is connected to the conductor 21 at positive potential by a conductor 59 such that, when the contact 52 is in its working and closed position, a circuit is established by a white indicator lamp 60, the conductor 22 then the return conductor 12 at negative potential, and when the contact 52 is in its rest and closed position, a circuit is established by a red indicator lamp 61, the conductor 22 and the return conductor 12.



   On the last wagon of the train, wagon which will be designated here by the expression "second station", there is provided an indication circuit substantially similar to that of the locomotive. A three-pole, two-position manual switch, designated as a whole by the reference number 62, has contacts 63, 64 and 65 capable, when the switch is closed, of completing circuits passing respectively through the conductors 12,10 and 11.

   Contact 63 is connected by a conductor 80 to a

 <Desc / Clms Page number 4>

 input terminal of a full wave rectifier 66 of any suitable type; the other input terminal of this rectifier is connected by a blocking capacitor 67 to the contact 64, as well as to a contact 68 of a detector relay 69, the winding 69a of which is connected to the output terminals of the. rectifier 66 so as to be excited by the latter. The contact 68 of the relay 69 is connected by a blocking capacitor 70 to the contact 65 of the switch 62. The relay 69 also comprises a contact 71 on and off.

   This contact 71 is connected to a local and separate battery 72 (such as the wagon battery), by a conductor 73; when contact 71 is in its working closed position, a white signal lamp 74 is energized by conductors 75 and 76, and when contact 71 is in its closed, rest position, a red warning lamp 77 is energized by conductors 78, 79 and 76.



    OPERATION.-
When the integrity indicator device is at rest, the two relays 45 and 69 are normally not energized. When we want to use the indicating device, we first close the manual switches 20 and 62 arranged respectively on the locomotive and the last wagon; if no fault exists in the brake control circuits comprising the control conductors 9, 10, 11 and 12, the relays 45 and 69, comprising the windings 45a and 69a, can be energized by pressing the button by hand. switch 35 provided on the locomotive for resetting to the initial position. The primary circuit of transformer 34 is thus closed and the alternating current at 3,000 cycles of its secondary 38 is thus applied to the clamping conductor 10 extending all along the train.

   This current flows through contact 64, capacitor 67, full wave rectifier 66 of the last car, then returns to the locomotive through conductor 80, contact 63, battery return conductor 12, passes through battery power supply 1, conductor 9, conductor 14, conductor 15 of master controller 2, conductor 16, fuse 17, conductor 18, conductor 29, the rupture arc suppression circuit comprising contact 24, the capacitor 26, the conductor 30 and the conductor 39, and finally closes the circuit arriving in the secondary 38 of the transformer 34. The full wave rectifier 66 of the last car is energized and consequently supplies direct current to the relay 69 by the conductors 81 and 82, thus energizing the relay 69 and closing the circuit through the contact 68 and the contact 71 in its working position.

   The contact 71 in its working closed position produces the excitation and the ignition of the white indicator lamp 74. The closing of the contact 68 of the relay 69 connects the clamping conductor 10, in which the alternating current flows at 3,000 cycles, to the release control conductor 11, through a circuit passing through contact 64, capacitor 67, conductor 83, contact 68, conductor 84, capacitor 70, contact 65, conductor 11, primary 41 of the transformer 42, cable 40, conductor 28, capacitor 25, contact 23, conductor 27, conductor 18, conductor 29, contact 24, capacitor 26, conductor 30 and conductor 39 terminating in secondary 38 transformer 34.

   The secondary 43 of the transformer 42 then supplies an alternating current to the rectifier 44 via the conductors 85 and 86; the output of this rectifier energizes the winding 45a of the relay 45, in order to close the contact 46 and thus to bring the direct current of the battery 1 into the repeater relay 37 comprising the winding 37a. The repeater relay 37 is energized and consequently closes the contacts 36 and 51, as well as the contact 52 in its working closed position.

   On closing, contact 36 bypasses manual reset switch 35, through conductors 87 and 88, and keeps the primary circuit of the transmission energized.

 <Desc / Clms Page number 5>

 trainer 34 until a fault is indicated in the brake control circuits or until switches 20 and / or 62 are opened by hand. The capacitor 49 and the resistor 50 establish a delay in the fall of the relay 37 after the excitation circuit of this relay has been cut, so that momentary cuts of the order of a few seconds in the excitation circuit do not produce not the failure of relay 37.



   Closing contact 51 of relay 37 establishes a current to energize a magnetic valve 53, which works with the pneumatic brakes to effect an application thereof, if the mechanic attempts an electro-pneumatic application of the brakes when the equipment presents. faults in its control circuits.



   Magnetic valve 53 is similar in operation to that described in U.S. Patents 2,573,442 of October 30, 1951 and 2,605,329 of July 29, 1952. Reference may be made to these patents. to better understand the operation of the valve 53 and its role in a braking installation.



   The closing of the contact 52 of the repeater relay 37 causes the lighting of the white signal lamp 60 indicating that the circuits are in working order. When the lamp 60 has ignited, the operator can release the switch 35, which returns to its open position under the action of a spring, not shown. In the event that the clamping conductor 10 extending all along the train fails, the two detector relays 45 and 69 respectively comprising the windings
45a and 69a lose their excitation and cause the lamps 61 and 77 to light.

   The relay 69 opens its contact 68 thus removing the excitation of the relays 45 and 37 mounted on the locomotive, as can be seen by considering the respective circuits of excitation of these relays; the result is that the connection is cut between generator 13 and transformer 34.



  When the fault has been repaired, the manual reset switch 35 must be operated so that the red lamps 61 and 77 go out.



   It can therefore be seen that a failure of the release control circuit including the conductor 11 also removes the energization of the detector relay 45, which in turn removes the energization of the repeater relay 37 and which opens the primary circuit of the transformer. 34 to cut the power supply to the clamping conductor 10 in alternating current and consequently to suppress the excitation of the repeater relay 69. The detector relay 37 of the locomotive and the detector relay 69 of the last car being no longer energized, the lamps red 61 and 77 at both ends of the train are on and indicate faulty circuits.



   A cut in the return conductor 12 would open the secondary 38 of the transformer 34 and thus remove the supply of the clamp conductor 10 with alternating current; this would result in the removal of the excitation of the detector relays 37 and 69, which would produce the lighting of the red lamps 61 and 77 to indicate such a fault.



   It must be emphasized here that, for all the faults assumed and mentioned above, at the same time as the relay 37 loses its excitation and the red lamp 61 lights up, the opening of the contact 36 of the relay 37 causes the opening of the primary 33 of the transformer 34 and thus clearly indicates the existence of a fault by completely removing the integrity indicator current through the verification circuits.



   An additional manual switch 89 can be included in this device, as seen in the embodiment shown in

 <Desc / Clms Page number 6>

 Figure 2, in order to control the brakes from the rear of the train. This can be achieved by connecting a conductor 90 to conductor 9 & 'power supply on the locomotive and running this cable all the way through the train to the rear car where the switch 89, comprising two contacts 91 and 92, can (par = , -means not shown) connect by these contacts the conductor 9 respectively to the clamping conductor 10 and to the release conductor 11, when it is desired to apply the brakes.



   The operation of the master controller 2 or that of the switch 89, with a view to controlling the brakes, does not bypass the passage of the alternating checking current through the brake control circuits and thus does not cause a fault indication, because inductance coil 93 prevents any test AC current from flowing through supply lead 9 or lead 90 (Figure 2) during brake application. Capacitors 67 and 70 prevent direct current flowing through the brake control circuits from interfering with the correct operation of the rear end test equipment in the event that a fault occurs in the control circuits. .



   In the embodiment shown in Figure 2, the circuits shown and the reference numbers used are the same as in Figure 1, except for the addition of additional switching circuits and a modification of the device for igniting the lamps 74 and 79. The modified device for lighting the warning lamps at the rear of the train comprises a signal supply conductor 94, connected to the conductor 90 , and a signal return conductor 95 terminating at return conductor 12; This eliminates the need to use the local battery 72 and the conductors leaving this battery, as in the case of FIG. 1.

   In this variant, a cut in the supply conductor 9 or in the conductor 90 is indicated by the absence of any indicator signal at the rear of the train.



   Although only two embodiments of the invention have been described and shown, it is understood that various modifications can be made to the devices described without thereby departing from the scope of the invention. invention.



    CLAIMS ..



   1. - Device for checking electrical control circuits characterized in that it is intended to check a control circuit and that it comprises in combination an electronic oscillator tube, comprising a plate supply circuit associated with said control circuit for producing a high frequency integrity check current through said circuit during operation of the tube, and a relay responsive to interrupting the flow of check current through said control circuit to open said plate supply circuit.

Claims

2. - Verification device according to claim 1, charac- terized by the fai @ that it comprises a delay means associated with said relay to prevent the latter from responding to a momentary interruption in the passage of the verification current to through the control circuit.

3. - Verification device according to claim 1, intended to verify the integrity of a control installation, comprising a control circuit and a direct current source capable of being connected to said circuit, and characterized in that it comprises an alternating current generator capable of being connected to the control circuit <Desc / Clms Page number 7> to pass an alternating current through it, a capacitor connecting the direct current source to the control circuit in order to allow the passage of the alternating current through the control installation independently of the connection of the source to said circuit,

a signaling means capable of providing an indication of the integrity of the installation and a means responding to the passage of an alternating current through the installation to control the establishment of said connection of the generator and the operation. of the signaling means.

4. A checking device, according to claim 1, intended to be applied to a control installation comprising a direct current source with positive terminal and negative terminal, a first and a second control cable which extend. from a first station, to a second station and are capable of being connected to the positive terminal, and a return cable connected to the negative terminal, said checking device being characterized in that it comprises a generator of alternating current, capable of being connected to the first control conductor in order to generate an alternating current therein,

a first AC conductive connection comprising a capacitor in series and joining the first control conductor to the return conductor at the first station, means responsive to the passage of alternating current through said first connection by establishing a second current conductor connection alternating current, comprising a capacitor in series, in order to allow the passage of the alternating current between the first control conductor and the second control conductor at the first station, a third conductive connection of alternating current comprising a capacitor in series and connecting the first control conductor to said positive terminal at the second station,

a fourth ac conducting connection comprising a capacitor in series and joining the second control conductor to said positive terminal, signaling means placed at the second station and capable of providing a sensitive indication of the integrity of the installation, a control means responding to the passage of an alternating current in the second control conductor by controlling the signaling means and the connection between the alternating current generator and the first control conductor.

5. - Verification device according to claims 1 and 4, characterized in that it comprises a second signaling means mounted at the first station and capable of providing a sensitive indication of the integrity of the control installation, and control means capable of responding to the passage of an AC current through the first AC conductive connection by actuating the second signaling means.

6. - Verification device according to claims 1, 4 and 5, characterized in that it comprises delay means for preventing said control means from responding to momentary changes in the passage of alternating current through the second control conductor, and so as not to indicate that the control installation is defective when faults of a short duration occur which are capable of correcting themselves.

7. - Verification device according to claims 1 and 4, characterized in that it comprises a generator capable of responding to the direct current supplied by the direct current source by passing an integrity verification current to high frequency through the control circuit, a switch initially connecting the control circuit to the generator, and a current sensitive device to keep the control circuit connected to the generator despite the opening of the generator. <Desc / Clms Page number 8> switch, this device being capable, after the end of the passage of the test current through the control circuit for a certain time, of removing the connection between the control circuit and the generator.

8. - Verification device according to claims 1, 4 and 7, characterized in that a signaling device indicating faults is made operative by the operation of the current sensitive device.

9. - Verification device according to claims 1 and 4, control installation, of the type in which three control conductors extend between a first control station and a second control station, comprises in combination a means to the second station to generate potential.

alternating integrity check, a first relay at the second station, a circuit comprising the first relay for applying said alternating potential to a selected pair of control conductors, a second relay at the first station connected to said selected pair of control conductors and supplied via these with alternating potential, this first relay being connected to the second relay via the third control conductor in order to suppress the alternating integrity checking potential on the pair chosen of control conductors when the second relay loses its energization or when the third control conductor is cut, an integrity indicating device connected to and controlled by the second relay,

and an additional integrity indicator device connected to and controlled by the first relay.

10. - Verification device according to claims 1, 4, 9 and 10, applied to a control installation in which two of the control cables can be selectively supplied with a DC potential difference with respect to the third cable, and characterized. in that it comprises means at the second station for generating a high frequency integrity check current, a circuit for applying this current to a selected pair of the control conductors, a rectifier at the first station, a another circuit connecting this rectifier to said selected pair of control conductors, which need to be excited by the test current, a relay connected to the rectifier to be excited by the latter and a means at the second station ,

connected to and controlled by said relay to remove test current on said selected pair of control conductors when the rectifier loses power.

11. - Verification device according to claims 1, 4, 9 and 10, characterized in that it comprises at the second station means connected to said relay via the third control conductor, in order to remove the current from checking in the chosen pair of control conductors when the rectifier loses its excitation or when the third control conductor is cut, an integrity indicator connected to said relay, controlled by the latter and arranged at the first station, and an additional integrity indicator provided at the second station, connected to said relay and controlled by it.

12. - Verification device according to claims 1, 4 and 9, characterized in that it comprises at the second station a first power source providing direct current and comprising a first terminal and a second terminal of opposite polarities, with the third control conductor connected to the second terminal, an alternating current source comprising two input conductors and two output conductors for high frequency alternating current, a three-pole two-position switch comprising three contacts, a circuit, <Desc / Clms Page number 9> in which are located one of these contacts and the third control conductor, connecting the two input conductors of the alternating current source to the first power source,

the first control conductor comprising means, consisting of a capacitor and one of the other contacts, for connecting one end of this conductor to the first terminal, a first transformer comprising a primary winding and a secondary winding , a first relay comprising several contacts, another circuit, in which a manual reset switch and one of said contacts of the first relay are connected in parallel, connecting said primary winding to said pair of conductors of output of high frequency alternating current, said second winding being connected in series with the first control conductor, a first rectifier disposed at the first station and connected to the first and third control conductors to be energized by them. this,

a second relay disposed at the first station, connected to and energized by the first rectifier, said second relay comprising a first contact and a second contact, another circuit comprising another capacitor and said first contact in its closed position , after the energization of the second relay, to establish a high frequency alternating current connection between the first control conductor and the second control conductor, a pair of lamps to indicate respectively, when they are on, the absence and the presence of a fault, a second power source, another circuit selectively connecting said pair of lamps, via the second contact of the second relay to the second power source to energize the lamps selectively,

in accordance with the excitation and the lack of excitation of the second relay, at the second station a second transformer comprising a primary winding and a secondary winding, the second control conductor being connected in series with said primary winding and being connected on the other hand to said first terminal via another capacitor and the third contact of the three-pole two-position switch, a second rectifier connected to said secondary winding and energized by the latter, a third relay controlled by the output of the second rectifier, a fault indicator, and finally an additional circuit interconnecting the third relay,

the first relay and the fault indicator to control the energization of the first relay and the fault indicator in accordance with the energization and the lack of energization of the second rectifier.

13. - Verification device according to claims 1, 4, 9 and 12 characterized in that it comprises a rectifier at one of the stations, a circuit comprising a first capacitor and connecting said rectifier to the selected pair of conductors control so that it is excited by the high frequency test current, a relay comprising a first and a second contact, this relay being connected to the rectifier so as to be energized by the latter, a second capacitor, another circuit comprising the second capacitor and the first contact to form a test current connection between two other conductors while said relay is energized, a potential source, an integrity indicator lamp and a voltage indicator lamp. defaults,

an additional circuit connecting these two lamps to the potential source via the second contact, these lamps being supplied selectively in accordance with the excitation and non-excitation of said relay 14. - Verification device according to claims 1, 4, 9, 12 and 13, applied to an installation in which the first and third control conductors are connected so as to form a first control circuit, the second and the third control conductors being connected so as to form a second control circuit,

<Desc / Clms Page number 10> a direct current source being disposed at the second station and means being provided for selectively connecting the direct current source to the first control circuit and to the second control circuit, and characterized in that it comprises a output transformer comprising a secondary winding interposed in series in the first control conductor, as well as a primary winding, a first relay comprising several contacts, a source of high frequency alternating current connected to said primary winding via a contact of the first relay to energize said primary winding while said contact is closed, a manual reset switch connected in parallel with said contact,

a circuit comprising a capacitor and interconnecting the first, second and third control conductors to the second station in order to provide circuits for the alternating current at high frequency while preventing the passage of direct current, a first rectifier at the first station, another circuit comprising a first capacitor and connecting the first rectifier between the first and the third control conductors so that it is energized by the high frequency alternating current, a second relay having a first and a second contacts, the second relay being connected to the first rectifier so as to be energized by the latter, a second capacitor,

an additional circuit including the second capacitor and the first contact to form a high frequency AC connection between. the first and the second control cable while the second relay is energized, a source of potential at the first station, an integrity indicator lamp and a fault indicator lamp, another circuit connecting these two lamps to said source of potential through the second contact to selectively excite said lamps in accordance with the excitation and non-excitation of the second relay, a second transformer arranged at the second station, connected in series with the second control cable and excited by the high frequency alternating current passing through this cable,

a second rectifier connected to said transformer and energized by the latter, the third relay comprising a single contact, the second rectifier applying its output current to the third relay to energize the first relay when said single contact arm is closed, the third relay being energized as long as all the control conductors are intact and losing its excitation when a cut occurs in one of these conductors, thus removing the excitation of the first relay, to open the connection between the source of high frequency alternating current and the primary winding of said output transformer until the connection is reestablished by use of the manual reset switch.

15. - Verification device according to claims 1, 4 and 9, intended to verify the integrity of a control system of the type comprising a first, a second, a third and a fourth control conductors extending. between the first and the second station, a source of direct current at the second station, the first and the fourth control conductors being connected to the opposite terminals of the source of direct voltage and transmitting the voltage of that source to the second station to the first station, the second and the fourth control conductors being connectable to form a first control circuit, the third and fourth control conductors being connectable to form a second control circuit,

a first switch at the second station for selectively connecting the DC voltage source to the first control circuit and to the second control circuit, a second switch at the first station to selectively connect the DC voltage source to the first control circuit, and to the second control circuit, this device being characterized in that it comprises <Desc / Clms Page number 11> an output transformer comprising a secondary winding interposed in series in the second control conductor and a primary winding, a first relay comprising several contacts, a high frequency alternating current source connected to said primary winding by a contact of the first relay for energize this winding while said contact is closed,

a manual reset switch connected in parallel with said contact, a circuit comprising a capacitor and interconnecting the second, third and fourth control conductors of the second station to provide paths to the high frequency alternating current flow while preventing the passage of direct current, a first rectifier at the first station, another circuit comprising a first capacitor and connecting the first rectifier between the second and the fourth control conductors for that it is excited by the alternating current at high frequency, a second relay comprising a first and a second contact, this second relay being connected to the first rectifier so as to be excited by the latter, a second capacitor,

an additional circuit comprising the second capacitor and the first contact of the second relay to form a high frequency alternating current connection between the second and the third control conductors while the second relay is energized, an indicator lamp indicator and a fault indicator lamp at the first station, another circuit connecting these two lamps between the first and the fourth control conductors through the second contact of the second relay to energize the lamps selectively in accordance with the excitation and the lack of excitation of the second relay, a second transformer arranged at the first station, connected in series with the third control conductor and excited by the alternating current flowing in this conductor,

a second rectifier connected to said transformer and energized by it, a third relay comprising a single contact, the second rectifier applying its output current to the third relay 'to energize the first relay when the single contact of the third relay is closed, the third relay being energized as long as the control conductors are all intact and losing its excitation as soon as a break occurs in any of these conductors, thus removing the excitation of the first relay to open the connection between the high frequency alternating current source and 1 primary winding of the output transformer until the connection is re-established using the manual reset switch " 16.

- Verification device according to claims 1, 4 and 9, characterized in that it comprises an alternating current generator, a circuit for energizing this generator, a first coupling means for coupling the output of this generator to the first control conductor, a first rectifier arranged at the first station and connected to the first and to the third control conductors so as to be excited by them, a first relay arranged at the first station and comprising at least a first and a second contact, this first relay being connected to and energized by the first rectifier, another circuit comprising a capacitor and said first contact in its closed position, after the excitation of the first relay,

to establish an alternating current connection between the first and the second control conductors, an indicating device connected to the second contact and capable of selectively indicating the integrity and fault conditions in accordance with the excitation and the lack of excitation of the first relay, a second rectifier at the second station, a second coupling means for coupling the second rectifier to the second control conductor for the purpose of exiting it by the high frequency alternating current passing in this cable,

and a fault indicator device controlled by the second rectifier and <Desc / Clms Page number 12> capable of interrupting the output circuit of the AC generator at the first coupling means and giving a fault indication while the second rectifier is not energized ,, and an integrity indication during that the second rectifier is excited by an alternating signaling current having at least one predetermined amplitude.