BE540413A - - Google Patents

Description

       

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  Synchronization circuits for remote control installation. the present invention relates to synchronization circuits for remote control installations and more particularly to synchronization circuits of this type applied to centralized traffic control installations for railways. The installations to which the present invention can be applied comprise a central station and several stations, which are interconnected by a communication path, on which are transmitted pulse-coded signals to effect the control of the apparatuses arranged along it. of the railway track, mainly for the purpose of controlling the trolling and to indicate to the central station the position or the state of these devices.

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   The present invention constitutes an improvement -of the installation described in the patent application filed in
France on September 15, 1954 and entitled "Installation of remote control, in particular to control railroad traffic" ....



   The installation according to the present invention also constitutes an improvement of the installations described and shown in United States Patents Nos. 2,411,375 and 2,442,603 of November 19, 1946 and June 1, 1948. respectively*
The present invention is also an improvement of the control installation described in the patent of the United States of America.
N. 2.350.688 of June 6, 1944. The remote control installations to which the present invention applies are of the time-regulated coded type using long and short coded elements, which are transmitted only one at a time on a unique way of communi-. cation.



   The constituent elements of the installations to which the invention applies are preferably assembled in the form of codqge, storage and extension groups, each containing a group of relays. These installations use a station coding group at each field station to transmit the control codes and to selectively receive the control codes; they also include extension and / or storage groups, as required, to associate the devices of each station with the station coding group.

   The central station preferably comprises an individual control panel for each group of traffic control devices, and a coding group, which is connected by a line circuit, or some other communication channel, with the group of traffic control units. station coding to selectively establish communication between each panel and the corresponding station group.

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   Remote control installations of this type are generally designed to transmit from the central station to the station in the field, either direct current coded pulses or high frequency carrier current coded pulses, with the aim of controlling the various devices. , and to transmit these same pulses from the field stations to the central station for the purpose of indicating the state of these devices. When direct current coded pulses are used, the control of the field station by the central station is carried out in a direct manner, that is to say without involving any auxilia @, re station.

   The direct current coded pulses are transmitted from the central station and are received directly by the coding groups of the field stations * On the contrary, when using carrier currents, it is necessary to provide an auxiliary station or station " remote line "between the central station and the stations in the field, this auxiliary station being controlled by a particular coding group of the central station. The remote line station receives and transforms the carrier current code pulses into ordinary DC code pulses, which are then used to control the field stations.



   Control indications are transmitted in an inverse manner from the field station to the central station, i.e. from the field station to the remote line station by the ordinary direct current coded pulses, and from the remote line station to the central station by carrier current coded pulses. An installation of the latter type is shown in the patent 2,350,668 mentioned above. Another installation of this type is also described in Manual No. 507, revised and reprinted, issued in March 1947 by the Westinghouse Air Brake Company and relating to a coded carrier control system for time-coded control installation. .

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   However, in any installation of this type, a method for synchronizing the coding action at the central station and at the stations is necessary, especially during transmission of a control code. This. Synchronizing action ensures that all coding groups simultaneously return to their normal rest positions. It prevents the coding action, between the central station and the stations, from being shifted during the following codes. Such a shifted coding action usually results in incorrect registration of control functions or control indications. This synchronization action is necessary in particular in the case where the coding action is stopped or interrupted by any fault in the equipment or in the communication channel.

   In this case, the return to normal position of all the equipment at the different points of the installation must be synchronized with great precision, so that all the coding groups return to their rest position at approximately the same instant. . The problem of synchronization of the installation arises with particular acuity in su @ - .tions controlled by carrier current pulses, since this -type of command .. coded is by nature more sensitive to faults and -aux other external actions affecting the communication channel than the continuous current impulse control.



   In the remote control installations used hitherto, different synchronization methods are employed depending on whether the control is effected by direct current pulses or by carrier current pulses. In this latter case, relays outside the central station coding group are provided to perform the synchronization action, as can be seen in: '- Manual 507-. Mentioned above.



   However, current installations are not always satisfactory, especially because they require additional relays which cannot be mounted in coding groups. An installation that does not require these external relays

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 riers would therefore present a considerable advantage over current installations.



   The aim of the present invention is therefore to provide a new improved synchronization device for remote control installations of the type described here.



   The object of the invention is also to provide such a synchronization device, which eliminates the need for synchronization relays outside the coding group of the central station.



   The invention also proposes to provide a synchronization device capable of operating, without any change in the equipment, either on a line controlled by direct current, or on a line controlled by a carrier current.



   The invention also proposes to use, within the coding group of the central station of a remote control installation, synchronization circuits which, in the event of a fault, guarantee that all the control relays. line are passed to their reverse positions before simultaneously returning to their normal positions.



   The synchronization circuits provided by the invention must produce an action identical to the stations in the field, during the course of the synchronization process, that the im-
Coded pulses are either of the direct current type or of the carrier current type.



   Other objects and characteristics of the invention will emerge from the description which follows and which refers to the accompanying drawing.



     As indicated above, if a synchronism fault occurs in any remote control installation, both in the case where the coded elements are transmitted by direct current pulses and in the case where they are transmitted By means of carrier current pulses, it is necessary that all line relays are simultaneously reset to their normal position. We found that it was better to place

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 first all these line relays in reverse position, if they do not already occupy this position, then allow sufficient time for the coding equipment at each point to return to normal position in this reverse position condition line relays.

   All the line relays are then placed simultaneously in the normal position and the coding equipment can return in a normal manner to its idle state. This action of returning to the normal position synchronizes the installation so that all the coding groups are in a position to produce a new coding action at substantially the same time. The present invention uses this general method of synchronization for a remote control installation.



   However, as indicated above, the installations currently in use include at the central station different synchronization equipment and circuits, as follows. whether the coded pulses are of the direct current or carrier current type. In accordance with the present invention, all of the synchronization circuits are in the line coding group of the central station and all operate in substantially the same manner, regardless of the fact that the control is by direct current. or by power line.

   The synchronization circuits can be adapted to direct current or carrier current installations, simply by making the appropriate connections on the terminals provided in the coding group ... '"
In accordance with the present invention, if a code is blocked with the central station line relay in the normal position, a cancel and sync relay is energized through the established sync circuits. This results in the excitation of a first transmitter relay. When this energizes and attracts its contacts, the central station line relay is driven in the reverse position, and the line circuit opens if using direct current coded pulses.

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   Opening the DC line circuit causes all station line relays to switch to the reverse position, if these relays are not already in this position. Sufficient time is then left for the relays of the time adjustment chain of the different coding groups for these relays to drop, in this condition of reverse position of the line relays. This causes the cancellation and synchronization relay to drop to the central station, as well as the first transmitting relay. When these relays drop, the central station line relay switches to the normal position and closes the line circuit. Closing this circuit puts all station line relays in the normal position, at about the same time as the central station line relay.

   The central station and the various stations can then return to the normal idle position, thus synchronizing all the coding groups on the line circuit.



   If a carrier current system is used, the energization of the first transmitting relay transmits a carrier current through the communication channel. This carrier current causes the opening of the remote direct current line. As a result, all the line relays of the stations switch to the reverse position. The relays of the time control chain of all coding groups then fall back into this inverse state condition of the line relays of the stations. As explained above, this results in the central station dropping the first emitting relay, which in turn causes the carrier current to be suppressed.

   The remote DC line circuit closes again and all station line relays go to normal at about the same time as the central station line relay.



  -The normal return of all coding groups to the rest position then occurs in synchronism.



   If a code is blocked in the installation according to the invention, with the central station line relay in position

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 Conversely, the fall of the time adjustment chain relays at the central station causes this central station line relay to switch to the normal position. These chain relays and all the rest of the central station coding equipment therefore return to the normal idle position. If a direct current line circuit is used, - the synchronization circuits energize the line circuit again with the normal polarity, in order to place all the line relays of the stations in the normal position at approximately the same , while the central station line relay.

   The time adjustment chain and the rest of the equipment, at each station in the field, then return to the normal state of rest in synchronism with the equipment of the central station. If a carrier current line circuit is used, the normal synchronization circuits according to the invention transmit a short pulse of the carrier current through the communication path to cause all the line relays of the ¯ line to switch to the reverse position. stations.



  This very short pulse of the carrier current is then interrupted. stinks to close the remote DC line circuit, placing all station line relays in the normal position at about the instant when the central station line relay comes to its normal position. The equipment of the stations in the field therefore returns to its normal state in synchronism with the equipment of the central station. ,.



   A particular embodiment of the synchronization circuits according to the invention will now be described with reference to the appended drawing, in which: FIG. 1 is a schematic view of a direct current line circuit and represents the line circuit connections to the central station, as well as the line circuit connections to a field station; - Figure 2 shows schematically a powerline line circuit, with the connections of the line circuit to the central station and the connections of the line circuit to the

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 remote line station, including connections made to the latter station on the remote direct current line circuit extending to field stations;

   - Figures 3a and 3b, when they are juxtaposed, with Figure 3a to the left, constitute a schematic view of the coding equipment of the central station and show in detail the new synchronization circuits according to the invention.



   The same references designate similar parts of the device in the various figures.



   In the various figures, the remote control installation, to which the new synchronization circuits in accordance with the invention have been applied, is that shown in the French patent application mentioned above. When the details of the remote control installation do not relate to the invention, the device has been shown in conventional form. Reference will be made to the French patent application above for a complete description of the operation of the installation. tion.

   In the drawing of the present application, when certain details of the remote control installation which are necessary to understand the present invention have been shown, for the various relays, resistors, transformers and other parts of the device have been used. , the same references as in the French patent application mentioned above, so as to establish a correspondence with the old installation. ',
Turning now to Figure 1, there is seen a typical direct current line circuit for such a remote control installation. At the central station, that is to say to the left of the figure, the line connections necessary to transmit the control codes and to receive the control codes by the line wires have been shown.

   At the field station shown on the right of the figure, analogous connections have been shown made on the line wires to receive the control code coming from the central station and to transmit the

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 control codes of this station at the central station.



   The references Y and Z designate two line wires which extend from the central station to the various field stations.



  These two line wires constitute the line circuit for the remote control installation in accordance with the invention and can also be used to provide telephone and telegraph communication channels, as has been explained above. kils of line designated by the same letters and represented in the French patent application already cited. This line circuit is normally energized by a current supplied by the line battery 31 of the central station. The positive terminal of this battery is normally connected to the line wire Y and its negative terminal to the line wire Z by the intermediary of the rest contacts b and c of the first transmitter relay OIT of the central station and similar contacts respectively. of the central station line polarity change mlais PC.

   The line circuit also comprises the line resistors R1 and R2 of the central station and the primary windings of a pulse transformer RT, by means of which the line relay OR of the central station is controlled when the latter. receives control codes. The control codes are transmitted by periodically opening and closing the line circuit, by means of the periodic operation of the relay Clt which opens and closes its rest contacts ± and c. A resistor R4 is connected between the work contacts b and c of the OIT relay, to cancel any electrostatic charge appearing on the line while the OIT relay is keeping the line circuit open. Various terminals 21 to 26 inclusive are provided in the connections of the line circuit to the central station as seen in Figure 1.

   The utility of these terminals will become apparent later, when the connections of power line carrier circuits are described.



   At the station in the field, the line circuit passes through the normally positive Y line wire, the closed contact has @

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Master-relay M, the winding of the line relay R, the resistor R3, the rest contact b of the M relay and the line wire Z. The relay R is a polarized relay; it operates between its normal position and its reverse position under the action of the pulses of a command code. While the installation is at rest, that is to say when there is no coding, this relay occupies its normal position.

   The operation of the relay R controls the line coding group of the station by the intermediary of its contacts a and b, in a manner which has been explained in detail in the French patent application already mentioned and which does not apply. not part of the present invention. The control codes are transmitted from the station by the operation of the. first relay transmits. tor lT, which periodically closes its make and break contacts to produce alternately bypassing the line circuit and closing this circuit via relay R.

   According to a common arrangement in remote control installations of this type ,. the master-relay M of the station is controlled at the start of a. control code, so as to change the polarity of the line circuit connections by opening its normally closed contacts a and b by closing the corresponding normally closed contacts. Initially, when does the; relay M, the line circuit is bypassed by the working contact of relay M and by a closed contact of one of the LBP time adjustment relays. However, this LBP relay is energized an instant later and remains energized for most of the check code, so that the 1T relay can perform the necessary coding.



   At the central station, the line relay OR is actuated by the pulse transformer RT during a check code.



  The RT transformer is sensitive to changes produced in the line current by the periodic bypassing and closing of the line circuit, which is effected by the transmitting relay lT at the station sending the control code. The circuit via

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 from which the OR relay is controlled goes through the upper terminal of the secondary winding of the transformer RT, terminal 29, the rest contact ± of the OM relay, the upper winding of the OR relay, terminal 30 and finally the lower terminal of the secondary winding.

   The OR relay is of the magnetic hold type; therefore, current pulses alternately flowing in opposite directions from the secondary winding cause this relay to operate alternately between its normal position and its reverse position. This operation of the OR relay controls the line coding group of the central station, by actuating its contacts a and b; this operation will be explained in more detail later. During the command codes, the secondary of the transformer RT is bypassed by the work contact c of the OM relay, this contact being closed at this time, so that the current pulses passing through the secondary winding have no effect on the OR relay.

   This relay is controlled during the command codes by the contacts d of the OlT and OM relays. This operation of the OR relay, between its normal and reverse positions, during any command code, is necessary to advance the action of the line coding group of the central station according to the number of signals required for this command code. .



  The circuit for passing the OR relay to its normal position during a command code passes through the central terminal 0 of a local battery 32, having a positive terminal B and a negative terminal N, through the lower winding of the OR relay, the rest contact d of the OlT relay, the open contact d of the OM relay and finally the N terminal of the battery. During the code signals, this relay OlT is energized and the control circuit of the OR relay passes through terminal B, the working contact d of the OlT relay, the lower winding of the OR relay and finally terminal 0.

   It can be seen that the flow of current, in these two control circuits, comprising the lower winding of the OR relay, takes place respectively in

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 opposite directions, so that this relay passes alternately in the normal position and in the reverse position and that the corresponding operation of its contacts a and b advances the action of the line coding group according to the signals of the code.



   If we now refer to Figure 2, we see a section of. characteristic carrier current line circuit, the central station and its connections to the line circuits, and the remote line station with its connections established both on the carrier current section and on the corresponding remote direct current line circuit extending beyond this point.



   Communication between the central station and the remote line station is effected by the line wires L1 and L2, by means of two high frequency carrier currents.



   In FIG. 2, the carrier current transmission means is shown for the sake of simplicity as consisting of two line wires, but it is understood that the installations considered are not limited to this arrangement. Another means can be used to transmit the coded carrier currents, for example a radio channel or a duplex channel obtained in a standard telephone or telegraph carrier current installation. The use of these other communication channels, between the central station and the remote line station, should be considered in remote control installations using synchronization circuits in accordance with the invention.



   Each carrier current channel is constituted by an oscillator-transmitter group at the original end, by the communication channel constituted here by two line wires, and by the receiver-amplifier located at the end of reception. The control codes are transmitted for example by the carrier current from the oscillator-transmitter DE1 of the central station to the receiver-amplifier RA1 of the remote line station. The oscilla-
 EMI13.1
 t <A t1'tï J8 'd ..: n ... i''rr1i'MWl> RAS lifier include a

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 corresponding lane, in the opposite direction, for control codes.

   Since the internal circuits of the oscillator-transmitters and the receiver-amplifiers do not form part of the present invention, these apparatuses have been represented in a conventional manner by rectangles; to know their internal circuits, one will refer to the manual n .507 already mentioned. Normally, each oscillator is inoperative, ie the current at carrier frequency is not transmitted. At the central station, the reverse contact of the TC transmitter and carrier relay shunts the oscillator. This TC relay is a normally polarized relay, it is not energized and its reverse contact a is therefore closed. Note that the TC relay is controlled by the circuits used for line connections in a DC installation.

   For example, the TC relay can be energized by a circuit which passes through terminal B of the local battery, terminals 21 and 22, the working contact ± of relay 01T, the contact, rest ± of the PC relay, terminal 26, the winding of the TC relay and finally the N terminal of the local battery. It can therefore be seen that, during the coding operation of relay 01T, relay TC is actuated periodically in a corresponding manner between the normal position and its reverse position.

   The other main circuit, which is used to control the relay TC to transmit a reset pulse at the end of a control code, passes through terminal B, the normal contact a of the OR relay, the working contact b of an OCS code stop relay, terminal 27, la, terminal 23, the rest contact b of relay 01T, work contact b of relay PC, terminal 26, the winding of the relay TC and finally the terminal N. Other control circuits of the relay TC, which are intended for particular functions, will be described later when the synchronization circuits according to the invention are described in detail.



   Powerline control pulses which are produced by the operation of the TC relay, are received at the remote line station by the receiving relay C, through the inter-

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 median of the RAI receiver-amplifier. Relay C, which is a polarized relay, is normally not energized and therefore normally occupies its reverse position.

   It periodically changes to its normal position under the action of each pulse of the carrier current, which is received from the central station., The direct current line circuit, which extends beyond the station. remote line to the various field stations, is controlled by relay C, which exerts - a control action similar to that exerted by the transmitting relay OIT on the direct current line circuit shown in figure 1 In other words, the remote direct current line circuit, comprising the two line wires Y and Z and shown in the right hand part of Figure 2, is normally supplied with direct current by a line battery 33 provided at the sta. distant line tion.

   The positive terminal of the battery 33 is connected to the line wire Y by the resistor R5, a primary winding of an RLT pulse transformer, the reverse contact a of relay C, and the rest contact of the polarity change relay RPC from the far line. Line wire Z is normally connected to the negative terminal of line battery 33 through resistor R6, another primary winding of the pulse transformer RLT, and the closed contact b of the RPC relay. It can therefore be seen that, when the relay C operates periodically under the action of the carrier current pulses received from the central station, the opening of its reverse contact a periodically opens this remote line circuit, in order to form the code of command, which is received by the various stations in the field.

   A resistor R7 is connected in shunt on the line wires Y and Z by closing the normal contact b of relay C, during the period when the line circuit is open. This operation allows the elimination of any electrostatic charge from the line circuit during the code opening period.



   Control codes, transmitted by any of the

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 stations connected to the remote DC line circuit are received by the remote line relay RL through the RLT pulse transformer, in a manner analogous to the operation of the central station OR line relay under the ac- tion of the pulse transformer RT, as explained with reference to FIG. 1. The relay RL is of the magnetically held type, like the line relay of the central station; it is actuated alternately between its normal position and its reverse position, during a control code, by the current pulses coming from the secondary of the pulse transformer.

   These current pulses result from the change in line current produced in the remote 'direct current' circuit by the encoding action of any of the field stations. The transmitter oscillator
OF2 at the remote line station is normally rendered inoperative by the normal contact a of the RL relay. The operation of this, between its normal position and its reverse position, causes periodic pulses of the second current, that is - that is, the carrier current, at high frequency, which must be transmitted to the central station. The RL relay is also controlled by the remote line coding group, which is conventionally shown in Figure 2 by the dashed line square drawn between the RLT pulse transformer and the RL relay.

   The circuits of the remote line coding group do not form part of the present invention and reference is made to manual no. 507 already mentioned for a full explanation of their operation.



   It suffices to indicate here that the remote line coding group relays and associated circuits effect a polarity change in the remote DC line circuit during codes. control, stabilizing the RL relay during control codes and restoring normal polarity in this circuit at the end of a control code, even if no reset pulse is received from the central station by the current por-

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 tor. This last action naturally includes the return of the relay RL to its nomle position, which it occupies while the installation is in the idle state.



   The carrier current pulses transmitted by the remote line station are received at the central station by the receiver-amplifier RA2 and cause the carrier current receiver relay OC of the central station to operate in a similar manner. the one following which the relay C operates at the remote line station. The OC relay is also a polarized relay, which is normally not energized and therefore occupies its reverse position. While the receiver-amplifier RA2 receives the carrier current pulses, the relay OC actuates its contact a between its normal position and its reverse position. This operation in turn causes that of the OR relay, which operates in a similar fashion between its reverse position and its normal position.



  The circuit to perform this operation goes through terminal 0 of the local battery 32, terminal 30, the upper winding of the rest contact c of the OM relay (closed during check codes), terminal 29, a capacitor CI, and then either the reverse contact a of the OC relay and terminal N, or the normal contact a 'of the OC relay and terminal B. It is obvious that the relay OR is thus actuated, between its normal position and its reverse position, by direct current pulses passing through its upper winding and in alternately opposite directions.

   As a result of this operation of the OR relay and the corresponding movement of its contacts a and% between their normal 'and' reverse 'positions, the central station coding group was holding the control code in a characteristic way. , which is specific to these remote control installations and which will be described a little later. Reference will also be made on this subject to the French patent application already mentioned, which describes in detail the reception of a control code by the coding group 'of the central station.

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   After having given the preceding brief overview of the operation of a remote coded control installation, with each type of coded pulses, an embodiment of the invention will now be described. If we refer to Figures 3a and 3b, we see part of the central station coding group serving for the remote control installation described in the French patent application already mentioned. These figures show detailed circuits only in the case where they form part of the invention or are necessary for the understanding thereof.



   Certain other parts of the station coding group, such as the central counting relay chain, are shown in a conventional manner. However, circuits for control functions, station selection and recording of controls are not shown, since they are not and are not part of the invention.



    . not necessary for the understanding of this one. For these parts, of the central station coding group, reference will again be made to the French patent application already mentioned.



   In Figure 3a, the line connections from the central station coding group are shown for a DC line circuit, which is analogous to that previously described with reference to Figure 1. Obviously. that the line connections could be for a powerline carrier line circuit, such as that described with reference to Figure 2, and reference will be made to these line circuit connections for a full understanding. invention. In the connections shown in Fig. Sa, an OLPF low-pass filter has been added between terminals 25 and 26 on the one hand, and the connection to the Y and Z line wires on the other hand.

   This filter is represented in the form generally used in such installations, so as to simultaneously allow the use of the two line wires by other communication channels.

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   In each command code formed by the 01T omitting relay of the central station, relay which cuts the line circuit in a direct current installation, the line circuit is open during the coded signals of odd rank and closed during the signals of even rank. In a carrier current line circuit, the oscillator-emitter, which is controlled indirectly by relay 01T, is not made inoperative during odd-numbered signals so as to transmit a carrier current pulse, and it is on. on the contrary, rendered inoperative during signals of even rank so that no carrier current passes through the line circuit.

   The character of each transmitted pulse, that is, whether it forms a short or long coded signal, is thus determined by the time interval during which the first transmitter relay 01T is energized or not excited. In particular, the central station coding group is placed in the desired state to transmit a control code, by energizing the OM relay master, which in turn closes circuits to effect the operation. periodical of the associated transmitter relay 01T.



   The OIT relay is alternately energized and not energized, so as to produce short coded signals, by the rest contacts of the odd-numbered counting chain relays which are connected in series: As will be explained briefly, the long coded signals of row, odd are produced by keeping relay 01T energized by different holding circuits. A second 02T transmitter relay is used. to participate in the adjustment of the time coded pulses. The 02T relay is energized when the OIT relay energizes itself. Once released, relay 01T cannot energize again as long as relay 02T has not released.



  Thus, the setting of the pulses of even rank is determined by the drop of relay 02T, which is maintained by holding circuits similar to those of relay 01T to produce the long coded signals of even rank.

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   When the 01T relay is energized at the start of any command code, the central station line OR relay is energized so as to switch to the reverse position. Closing the reverse contacts of the OR relay energizes the time adjustment relays and the counting chain relays.The OR relay alternately switches to its reverse position and to its normal position during a command code, each time the relay OIT gets excited or falls down respectively.

   Thus, the OR relay successively actuates the relays of the counting chain step by step to advance the coding action. This action of the OR relay also exerts an action on the operation of the adjustment relays over time, by determining the long and short pulses of the code.



   For example, when the OR relay switches to the reverse position on the first signal of the code, it closes a circuit passing through terminal B, its reverse contact b, the rest contact a of the time-setting relay 02L, the contact rest a of the time-regulated relay OLBP, the winding of the regulation relay 01L and terminal N. When relay 01L is energized, its work contact a closes to complete a circuit passing through terminal B, the contact reverse b of the relay, OR, the winding of the relay 02L and terminal N, so that the relay 02L is also energized and draws its contacts.



  At this moment, the Q2L relay completes a holding circuit which appears clearly and passes through its own work contact, the opening of its contact is rested, cutting at the same time the excitation circuit of the 01L relay. However, all relays in the time adjustment chain are fall retarded, and fall times are further increased by righting shock absorbers. Thus, relay 01L, although not being energized, remains in the high position for a considerable time. The two relays 01L and 02L being in the high position, a circuit is formed by terminal B, the work contacts b in series of these two relays, the winding of the OLP adjustment relay and terminal N, so that the OLP relay gets excited and attracts its contacts.

   Contact closure

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 work of the OLP relay completes a circuit which appears clearly and intended to energize the time-regulated relays
OLB and OLBP. When these two relays are energized, the OLBP relay is energized by a circuit comprising the work contact a of the relay
OLB, so that these relays drop out successively when the OLP relay itself drops out.



   When relay 02L is energized during the first signal of the control code, its work contact .2 closes to switch from the reverse contact b of the OR relay to the normal contact b of this relay the excitation circuit of the 01L relay. Then, the work contact a of the OLBP relay closes to maintain this last connection of the 01L relay until the code is terminated. As a result, the 01L and 02L relays are then alternately energized, the 01L relay by the normal contact b and the 02L relay by the reverse contact b of the OR relay, in response to the periodic operation of the OR relay armature.

   The 01L and 02L relays remain energized for the duration of the short coded pulses, the 01L relay drops during each long coded signal of odd rank while the 02L relay drops during each long coded signal of even rank. These relays therefore serve to indicate the character of a code and to control, together with the relay OLP, the length of the long signals of a code generated by the associated transmitter relays OIT and 02T. The OLB relay and its relay. OLBP repeater are bridge relays. Each of them maintains its work contacts closed for the duration of a code and is used to prepare different local circuits, when the coded operation of the OR relay begins, and to open them when this operation stops.



   When relay 01L energizes and closes its work contact c, a circuit is completed to energize the first relay 01 of the counting chain. This circuit passes through terminal B, the inverse contact a of the OR relay, the rest contact b of the OLBP relay, the working contact c of the 01L relay, wire 34, the winding of relay 01, and finally terminal N. When the OLBP relay is energized '

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 possibly, its work contact b closes to transfer the energy from wire 34 to wire 35, and from there to terminal N passing through the rest contact b of the second counting relay 02, the work contact a of the relay 01 and the winding of relay 01, in order to energize the first counting relay.

   When the OR relay goes to its normal position on the following coded signal, a circuit is completed by terminal B, the normal contact a of the OR relay, the work contact c of the OLBP relay, wire 36, the closed contact has to relay 08, the work contact b of relay 01, the winding of relay 02 and finally terminal N. When energized, relay 02 opens its rest contact b to cut the holding circuit of relay 01, which drops to this moment.

   When the OR relay goes back to the reverse position, the 03 relay is energized by a circuit passing through the B terminal, the reverse contact a of the OR relay, the con-. working contact b of OLBP relay, wire-35.9 the open contact a of relay 01, working contact b of relay 02, the winding of relay 03 and terminal N. There are other relays in the counting chain energized in an analogous manner while the OR relay passes alternately to its normal position and to its reverse position.



   When relay 08 is energized, an OCR chain repeater relay is also energized to establish circuits to again use count relays 01 through 07 inclusive. As explained in the French patent application already mentioned, it is possible to add to the counting chain as many additional counting relays as are necessary for the coding action. However, we do not have shown here as ordinary relays 01 to 08. The relay
OCS for stopping the code is excited in a similar manner on the last selected signal of the code, whatever the length of the latter, as was explained in the French patent application referred to above.

   Energizing the des relay stops all coding action and initiates the reset action, which returns the coding group to the normal idle state. '

 <Desc / Clms Page number 23>

 
The coding action of the central station coding group is initiated by closing a start contact shown in Figure 3b. This start contact can be a push-button which is closed by hand, or can be a relay contact, or even any other similar device which can be closed when desired, to initiate the action of coding. In the preferred embodiment, the start contact is a contact of a starter relay which can be energized by a hand operated push button in the controller.

   The starter relay is energized when this push-button is acted on, and remains energized until it drops out at the appropriate time during the coding action. The closing of the start contact shown causes the start of the coding action by energizing the master relay OM of the central station. The excitation circuit passes through terminal B, the start contact, wire 37, the rest contacts of relays 02L and 01L, the winding of relay OM and terminal N. When relays OLB and OLBP are energize, a holding circuit is established for the OM relay through terminal B, the rest contact d of the OSC relay, wire 38, the work contact d of the OLBP relay or the work contact of the new OLB relay, the work contact a and the OM relay winding, and finally the N terminal.

   Since the OLB and OLBP relays remain energized during the entire code, the OM relay is therefore energized and remains in the up position also during the entire coding action. The OM relay is characterized by a fall delay, which is further increased by a damping rectifier, so that when this relay has attracted its contacts, it forms a bridge during the time elapsing between opening of the open contact d of relay 01L of the - .. excitation circuit and closing of the open contact b of relay 0LB of the holding circuit.

   In other words, the OM relay is: maintained in the high position, thanks to its delayed fall characteristic, from 'the moment when the idle contact d of relay 01L, in its excitation circuit, -s' opens, until the work contact b of the OLB relay, in its holding circuit, is formed.

 <Desc / Clms Page number 24>

 



   When the OM relay energizes, it completes a drive circuit of the OIT relay, which therefore energizes at this time. This circuit passes through terminal B, the rest contact c of the relay
OCS, the rest contacts c of all counting relays of odd rcng, wire 39, work contact b of relay OM, rest contact 'b of relay 02T, the winding of relay 01L and finally terminal N. Ce circuit serves as a pulse circuit to control the coding action of relay 01T during short coded signals, the odd-numbered counting relays energizing for. end or start the various short pulses. When relay 01T energizes and closes its work contact a, it completes a holding circuit through which the long coded signals are produced.

   During the station selection part of the coding action, the holding circuit extends from the work contact a of the OIT relay, passing through wire 40 and one of the work contacts d of the relay 03, 05 or 07, up to the station selection part of the control circuit not shown in the present application. During the last part of the code, the holding circuit is transferred, by the energization of the OCR relay, to the circuit passing through the working contact e of the 01L relay or the working contact'b of the OLP relay, wire 41, the working contact b of the OCR relay, the work contacts of the various counting relays of the same rank, and the function control circuits, which can be manually adjusted by the local operator as he wishes.



   When relay 01T energizes, closing its working contact closes an obvious circuit to energize the second 02T transmitter relay, which therefore energizes. The closing of the working contact a of the latter prepares the establishment of any one of the different holding circuits, by which, when the relay 01T drops out, the long coded signals of even rank are determined.

   During the part of the code devoted to station selection, the holding circuit extends from] - * winding of relay 02T, passing through the rest contact e of the

 <Desc / Clms Page number 25>

 relay 01T, the work contact has relay 02T and wire 42, up to the work contacts c of counting relays 02, 04, 06 and
08, and from there to the station selection control circuits, which are not shown in the present application.

   During the last part of the code, the holding circuit is transferred by the OCR relay to the following path: wire 42, the work contact e of relay 02L or the work contact c of the OLP relay, these two work contacts being in parallel, wire 43, the work contact c of the OCR relay, the work contacts d of the various even-numbered counting relays, except for relay 08 and finally the various function control circuits, which are manually adjusted to give the even numbered signals of the code the length necessary for the desired commands.



   The control coding action of the central station coding group is stopped by the code stop relay OCS, which is energized during the last selected signal of any code.



   As explained in the patent application cited above; only the coded signals of even rank can be chosen as the last signal of the code. When the rest contact d of the OCS relay opens, the OM relay loses its excitation, following the breaking of its holding circuit, and drops out an instant later. Opening the rest contact c of the OCS relay cuts the pulse circuit of the 01T relay, which remains in the low position when the 02T relay drops again. Since relay 01T remains in the low position, the central station OR line relay remains in its normal position, which it occupied during this last signal of the code.

   As a result, the delayed chain relays drop out in order, starting with relay 02L, the holding circuit of which is cut by reverse contact b of relay OR. The fall of the delay relays continues in the order OLP, OLB, OLBP and finally 01L. Although the circuit is not shown in detail in the present application, it can be said that the code stop relay OCS remains energized by means of a holding circuit, which is not

 <Desc / Clms Page number 26>

 not open until the OLB relay drops out. Thus, the OCS relay remains in the upper position during the greater part of the return action to the normal position exerted by the coding group of the central station.

   When the OLBP relay drops, it places the central station coding group in the normal state and the next fall of the 01L relay places this group in the state required to accept or transmit a new code.



   The reception of a control code by the central station coding group will now be briefly explained. The transmission of such a control code by a field station has been described briefly but sufficiently above. In the direct current line circuit shown in FIG. 3a, the initial bypassing of the line circuit to the field station causes the line relay OR of the central station to switch to the reverse position.



  In other words, the initial change produced in the line current flowing through the primary windings of the RT transformer causes a current pulse in the secondary winding, which energizes the upper winding of the OR relay so that it passes in reverse position. If a powerline carrier line circuit, such as that shown in Figure 2, is used, the first carrier current pulse from the remote line station causes the OC relay to switch to the normal position, closing its contact. normal a so as to complete a circuit defined previously and comprising the rest contact of relay OM, and. to energize the upper winding of relay OR in a direction such that this relay switches to the reverse position.

   Thus, whether a direct current line circuit or, on the contrary, a carrier current line circuit, is used, the first coded pulse coming from the station in the field causes the line relay of the central station to switch to the reverse position.



   The closing of the reverse contacts of the OR relay causes the operation of the adjustment chain over time in the manner described above and initiates the operation of the relays of the counting chain, as explained above. The

 <Desc / Clms Page number 27>

 closing the reverse contacts of the OR relay also energizes the PC line polarity change celais. 'The PC relay excitation circuit passes through terminal B, the reverse contact s of. relay OR ,, the closed contact of the OLBP relay on. contact rest of the OM relay, wire 44, the rest contact of the OCS relay, wire 45,
The winding of the PC relay and the. terminal N.

   When the PC relay switches off, closing its work contact activates its PCP repeater relay. Closing the work contact a of the PC relay completes a holding circuit intended for this relay and passing through the terminal
B, its work contact a, the work contact e of the OLBP relay, and finally the rest of the excitation circuit already described. If a direct current line circuit is used, contacts b and c of the PC relay change the polarity of the current supplied to the line circuit to make all field stations inoperative.
1-except for the one that transmits the control code.

   During this polarity change action the secondary winding of the transformer RT is momentarily shunted by a circuit; this circuit passes through the upper terminal of the secondary winding of the transformer RT, the NC contact 2 of the PCP relay, the working contact d of the PC relay, terminal 28 and the lower terminal of the secondary winding. When the PCP relay energizes, this shunt is cut. In addition to this shunt applied to the secondary winding of the pulse transformer to stabilize the OR relay, a circuit is also completed passing through the lower winding of the OR relay to similarly maintain this relay in its reverse position. .

   This circuit passes through terminal 0 of the local battery, the lower winding of the OR relay, the rest contacts d of the 01T and OM relays, the work contact f of the PC relay, the rest contact b of the PCP relay and the terminal B of the battery. It is evident that the current flowing in this circuit,, through the lower winding of the OR relay, flows in the direction opposite to the arrow, so that the OR relay remains in the reverse position. If a powerline carrier line circuit is used, energizing the

 <Desc / Clms Page number 28>

 PC relay is used to connect the carrier current CT transmitter relay to the work contact b of the OCS relay.

   This connection is established by a circuit which, as seen in figure 2, passes through the winding of the relay TC, terminal 26, the work contact b of the PC relay, the rest contact b of the OIT relay, the 'terminals 23 and 27, and finally the working contact 12' of the OCS relay. The usefulness of this circuit will appear a little later when the termination of the control code is explained.



   The coding action of the central station during the control code continues, controlled by the operation of the OR relay, which exactly follows the control code transmitted by the field station. During the selected final signal of this control code, the OCS relay of the central station is energized again, as explained for the control code. When energized, this relay establishes its holding circuit, which is not cut until the control chain OLB relay is in; the time has not dropped during the reset action. initial. Opening the rest contact of the OCS relay removes the excitation of the PC relay by cutting the latter's holding circuit, which consequently drops out.

   As a result, the PCP relay loses its excitation, but this relay being delayed on fall remains in the high position for a certain time after the loss of its excitation. Dropping the PC relay also restores the DC line circuit to its normal polarity. During this polarity change action, the secondary winding of the pulse transformer is shunted again, so that the change of current in the line circuit has no effect on the OR relay.

   This shunt is established in a manner analogous to the previous shunt, that is to say passes through the upper terminal of the secondary winding, the work contact c of the PCP relay, the d contact of the PC relay. , and the lower terminal of the secondary winding, The OR relay is also maintained in its normal position by the run through its lower and cireu- winding.

 <Desc / Clms Page number 29>

 in the circuit passing through terminal 0, the lower winding of the OR relay, the rest contacts d of the 01T and OM relays, the rest contact f of the PC relay, the open contact a of the PCP relay and terminal N. This current flows in the desired direction to keep the OR relay in normal position.

   It follows that the relays of the
The control chain over time returns to the rest position, as explained at the end of the command code, the relays drop in the order 02L, OLBP and 01L. As before, the fall of the OLBP relay returns the central station coding group to its normal state. and after the 01L relay drops the whole group is ready for a new coding action.



   If a carrier current line circuit is used, the energization of the OCS relay causes that of the TC relay via a circuit passing through terminal B, the normal contact has of the OR relay, wire 47, the working contact. b of the OCS relay, wire 48, terminal 27, and then, retort as seen in figure 2, terminal 23, con. rest tact b of relay 01T, work contact b of relay PC, winding of relay TC and terminal N.

   When the TC relay switches to the normal position, a pulse of the control carrier current is transmitted by the line circuit to reset the remote line station to the position of reset and to return to the normal state 1 remote line circuit at direct current, beyond this station. This carrier current pulse ends when the PC relay drops to open its work contact b and remove the excitation of the TC relay.



   It can be seen that the action of resetting and synchronizing for a control code or for a control code, whether a DC line circuit or on the contrary a carrier current line circuit is used, takes place. without any additional relay in addition to those provided for in the central station coding group. The ordinary terminals which are required to connect a powerline line circuit or a line circuit to

 <Desc / Clms Page number 30>

 direct current, are sufficient to also provide the connections necessary for the various actions of returning to the normal position and synchronization of such a line circuit.



   We will now explain how the installation returns to the normal position in the event of a fault.



   It will be remembered that, in the event of a fault occurring in the coding equipment or in the communication channel itself, the problem to be solved consists in returning to the rest position, at the same time and analogously, all the coding groups of the central station and of the various stations in the field.



  This is generally achieved by arranging so that all the station relays R and the central station relay OR are in the reverse position and that the time relays have had the necessary time to return to idle under these conditions. . All line relays are then placed in normal position simultaneously, or as simultaneously as possible, and the time relays can then return to idle at the same time, both in the central station and in the field station. The simultaneous return to rest of the time relays with the line relays in the normal position synchronizes the different coding groups and at the same time puts them in the desired state to produce a new coding action.



   A command code can be stopped on an odd-numbered signal following a fault. For example, the 01T relay can be kept energized by one of the wires 39, 40 or 41. In this case, the OR relay is kept in the reverse position and the 01L, OLP, OLB and OLBP timed relays drop out. The OR relay being maintained in the reverse position, the 02L time delay relay remains energized and in the high position. The fall of the OLBP relay removes the energization of the OM relay, while opening and restoring the circuits of the counting and selection relays. the fall of the OM relay, while the OR relay is in the reverse position, completes the circuit defined above to energize the PC relay, which attracts its contacts

 <Desc / Clms Page number 31>

 and in turn energizes the PCP relay. The fall of the OM relay removes the excitation of the 01T relay.

   However, this last relay being delayed in the fall remains in the high position for a certain time before falling again.



   . With relay 01T energized or in the high position, the DC line circuit remains open at this time. If a powerline carrier line circuit is used, the TC relay remains energized while the 01T relay remains in the up position, both when the PC relay is energized and when it is on the contrary de-energized. The circuits by which the relay TC remains energized are shown in figure 2 and become evident by examining this figure. Thus, at each station in the field, the line relay R remains in the low or reverse position and the time relays drop in the same order as at the central station, relay 2L remaining energized. The fall of the LBP relay at each station in the field opens the circuits of the counting and selection relays to prevent a new reception of any code.



  This action occurs both when the line circuit is direct current and when it is carrier current controlled by the central station.



   When the PCP relay attracts its contacts, the OR relay is energized and goes to the normal position under the action of the current flowing in the circuit passing through terminal 0, the lower winding of the OR relay, the rest contacts d of the 01T relays and OM, the work contact f of the PC relay, the work contact b of the PCP relay, the idle contacts f of the OLBP and O @ L relays and finally the N terminal. The possible fall of the 01T relay closes the line circuit with direct current, but the line relays in the field do not immediately switch to the normal position, because the line current polarity is still inverted by the contacts b and c of the PC relay.

   In the carrier line circuit, the fall of relay 01T opens the ordinary excitation circuit of the TC remake but, since the relay OR occupies its position at this point

 <Desc / Clms Page number 32>

 Normally, another circuit is complete to energize the TC relay, so that the line relays at the various field stations remain in the down position.

   This TC relay excitation circuit passes through terminal B, the normal contact a of the OR relay, wire 47, the open contact 12 of the OCS relay, the, ¯ (il, 49, the rest contacts g of the relay 01L and OLBP, terminal 27, and, as can be seen in the figure, terminal 23., the rest contact of relay 01T, work contact b of relay PC, the winding of relay TC and finally the terminal N ..



   When the OR relay occupies its normal position, the chain of time relays of the central station is energized again and its various relays attract their contacts. The opening of the contact will reverse of the OR relay suppresses the excitation of the relay PC, which drops out before its holding circuit does. be completed by closing the work contact e. of the OLBP relay. The fall of the relay. PC suppresses the excitation of the PCP relay, and that of the TC relay in the case of the powerline line circuit. The OR relay occupying its normal position; the time delay of the central station then fall back to the normal order because the excitation of the relay
02L is removed, relay 01L being the last to drop.

   At the same time, 12 'line current, in the' direct current line circuit, is restored 'to its normal polarity by the drop of the relay.
PC and line relays: stations return to normal position. In the powerline line circuit, with the CT relay de-energized, the station line relays return to their normal position. In both cases, the time relays of the field stations are energized again and then drop in the order indicated, the line relays of the stations being in the normal position and the IL relay of each field station being the last to drop.

   Thus, the coding groups of the central station and of each station in the field are brought back to the normal state more or less simultaneously, so that the synchronization of the binding circuit is obtained, both in the case of direct current and of

 <Desc / Clms Page number 33>

   carrier current.



  If a convenient code ends on a coded signal of even rank before the final selected signal, because the 01T relay is faulty and does not attract its contacts, the central station OR line relay is kept in the normal position. and the time relays of the central station drop in the normal order. The OLBP relay drops the counting and selection relays, as well as the OM relay. The 01L relay is the last to drop as usual. The R line relays of stations, whether one or another type of line circuits, res. ten.t energized and their time relays drop in normal order, as at the end of a complete code, relay lL being the last to drop.

   In the event of such a fault, the entire action is analogous to that occurring at the end of a normal command code, with the difference, however, that the OCS relay is not energized, and the synchronization of all stations and the central station is maintained in the usual manner.



   If a control code is blocked on an odd-numbered signal, as would be the case, for example, if relay 1T of the field station remained energized following a fault, the OR line relay of the central station remains in the reverse position until the chain relays are adjusted in time. In this reverse position condition, this OR relay falls, the 02L relay remaining energized. The OR relay then returns to the normal position following the closing of the OFF contact of the OLBP relay.

   The circuit controlling this action passes through terminal 0 of the source, the lower winding of the OR relay, the rest contacts d of the 01T and OM relays, the work contact! of the PC relay, the work contact b of the PCP relay. the rest contacts 1 of the relays
OLBP and 01L and finally terminal N. The PC and PCP relays are already in the high position, since the central station receives a counter code. When the OR relay switches to the normal position, the PC relay loses without excitation due to the opening of the reverse contact.

 <Desc / Clms Page number 34>

 lais OR, the opening of the work contact of the OLBP relay having already opened the holding circuit of the PC relay. If a direct current line circuit is used, the drop of the PC relay restores the normal polarity of the line current.

   All station line relays, including that of the field station which has just transmitted, then return to their normal position and the station coding groups simultaneously return to idle in this normal condition. When the OR relay switches to the normal position, the time adjustment chain at the central station is energized again, then drops back to the normal order, relay 01L being the last to drop. Then all the relays lines return more or less simultaneously to the normal position, the restoring action exerted = on a direct current laundry circuit, at the central station and at the stations in the field, is synchronized.



   If a power line carrier circuit is used, the CT relay is energized when the OR line relay is in its normal position. The TC relay excitation circuit passes through terminal B, the normal contact a of the OR relay, wire 47, the rest contact b of the OCS relay, wire 49 ,, the rest contacts g of the 01L and OLBP relays, terminal 27, terminal 23, the rest contact b of the relay 01T, the work contact b of the PC relay, the winding of the TC relay, and finally the terminal N. The pulse of the carrier current, which is transmitted when the relay TC 'changes to the normal position, ensuring that all the R line relays of the stations are in the reverse position, opening the remote direct current circuit at the remote line station.

   The drop in the PC relay, which occurs immediately after, removes the excitation of the TC relay, which drops to remove the carrier current again. The remote DC circuit is thus closed with a now normal polarity of the line current and all the line relays of the stations switch to the normal position. This happens at the same time, or shortly after the central station OR line relay has passed.

 <Desc / Clms Page number 35>

 in normal position. All the coding groups of the stations then return to idle, in this condition of the normal position of the line relays, substantially in synchronism with the coding group of the central station.



   If a control code is blocked on a coded signal 'of even rank, other than the last signal selected from the code, following a failure of relay 1T of the field station to be energized, relay OR; remains in normal position, and the 02L, OLP, OLB and OLBP timing relays drop out. At the station in the field which was transmitting, the relay R remains energized, while the delayed relays 2L, LP, LB and LBP drop. - The relay LB of the station in the field drops the master-relay M, which reverses the line connections from relay R to this station, so that the line relay switches to the reverse position by energizing the time relays again, which then drop back in the order IL, LP, LB and .LBP.

   The switchgear is thus in the same state at the transmitting field station as at the other field stations, where the relays of the time adjustment chain are held in the low position in the reverse position condition of the relay. line, with relay 2L in the high position.



   At the central station, the fall of the OLBP relay suppresses the energization of the PC and 01L relays. The PC relay drops out before the relay
01L, which is of the delayed fall type. This action activates a cancellation and synchronization relay XS, The relay XS excitation circuit passes through terminal B, the rest contact e of the PC relay, the work contact d of the PCP relay (still closed), the work contact h of relay 01L, the 'idle contact f of relay 02L, the winding of relay XS and finally terminal N. When relay XS is energized, a circuit is completed by terminal B, the open contact b of relay XS, the open contact b of the OM relay, the open contact b of the 02T relay, the winding of the OIT relay and the N terminal.

   Relay
01T is excited by this circuit and attracts its contacts. The result is that the 02T relay is energized, as has already been explained, and that it

 <Desc / Clms Page number 36>

 also attracts its contacts. At this moment, the energizing circuit of relay 01T is transferred to a path passing through the working contact b of the 02T relay and the working contact a of the 01T relay; relay 01T remains energized and in the high position.



   The closure . of the working contact d of relay 01T completes an obvious circuit passing through the lower winding of relay OR, in order to switch this relay to the reverse position. This action energizes the central station time relays and the PC relay again, so that all these relays attract their contacts.



  When the OLBP relay is energized, closing its work contact h closes a relay XS holding circuit; this circuit passes through terminal B, the working contact h of the OLBP relay, the working contact it has and the winding of the relay XS, finally, the terminal N. If the line circuit is controlled by a current continuous, energizing relay 01T opens the line circuit through its rest contacts b and d, which guarantees that all R line relays are in a non-energized state. If the line circuit is controlled by a carrier current, the energization of relay 01T immediately causes the energization of the relay TC by an obvious circuit comprising the work contact c of relay 01] ¯ and the closed contact c of the relay PC. When the PC relay is energized, the TC relay excitation circuit is transferred to the make contacts b of the 01T and PC relays.

   The TC relay thus switches to the normal position and a carrier current pulse is transmitted through the line circuit to the remote line station.



  As a result, the remote DC circuit is opened by reverse contact a of relay C, to ensure that all station line relays are de-energized.



   With the central station OR line relay remaining in the reverse position, the central station time relays then drop out = starting with relay 01L and continuing in order with the OLP, OLB and OLBP relays, the remaining OL relay in high position. The fall of the OLBP relay opens the holding circuit of the XS relay, which therefore drops out. It follows that the relay

 <Desc / Clms Page number 37>

 
ILO loses its excitement and also falls back.

   The fall of this relay causes the OR relay to switch to the normal position, via a circuit passing through terminal 0, the lower winding of the OR relay, the rest contacts d of the 01T and OM relays, the work contact f of the PC relay, the work contact b of the $ CI 'relay, the rest contacts of the OLBP and 01L relays, and finally the N terminal. Switching the OR relay to its normal position removes the excitation of the PC relay, which drops out, and energizes the relays of the time adjustment chain of the central station coding group. This group now begins to return to rest, in this condition of normal position of the OR relay, the 01L relay being the last to drop among the relays of the time adjustment chain.



   In the direct current line circuit, the drop of relay 01T closes the line circuit and the next drop of the PC relay restores the normal polarity of the line current. All . Line relay stations pass, then in the normal position, including the field station relay which transmitted the control code. At each station: the time control chain and the rest of the line coding group return to idle in the usual way .; with line relay R in normal position. If a carrier current line circuit is used, the drop of the relay PC 'removes the excitation of the TC relay, which returns to the reverse position, by removing the carrier current. At the remote line station, the absence of the carrier current causes relay C to return to the reverse position, which thus closes the remote line circuit with direct current.

   Since the DC current of the remote line circuit has normal polarity, all station line relays go to the normal state and the line coding groups return to idle in this condition. Thus, in either case, all the R line cells and the OR line relay of the central station return to their normal position at about the same time and the coding groups of the central station and the stations in the field. all return to rest in synchronism.

 <Desc / Clms Page number 38>

 



   It can be seen that in each case, when the coding action is stopped or blocked as a result of some fault in the equipment or the communication channel, the line relays OR and R return to approximately normal position. ., at the same time, whatever their initial positions, so that each of them can drop, in the normal order, its chain of adjustment relays in time, in order to place all the coding groups in the proper reception state before central station relay 01L or any of the stations IL relays drop; we can thus start a new code. Generally, the central station coding group has a better chance than the others to send the following code, because the 01L relay drops out slightly before the IL campaign relays.



   When the installation is in the normal or rest position, the central station OR line relay can be controlled by one or more pulses of a foreign current, or as a consequence of a temporary fault in the communication channel. In this case, the first inversion of the OR relay energizes the PC relay. This reverses the polarity of the line current, in the case of a direct current line circuit, which causes all R line relays to drop in order to prevent the start of a code by any station. In a powerline line circuit, a similar pulse or line fault would also cause relay C to operate at the remote line station.

   This operation of relay C opens the remote DC line circuit, and thus prevents field stations in that circuit from starting a code. When the fault is over, the installation returns to the normal position in the same way as previously, as explained in the case of the interruption of a control code, the feel operation being determined by the position of the OR relay. at the end of the blackout period.



   It has been shown that, thanks to the synchronization circuits according to the invention, a remote control installation,

 <Desc / Clms Page number 39>

 to which these circuits have been applied, maintains synchronism between the central station and all the stations on campaign during normal operation and so Restoring action necessary to remedy a fault occurring in the equipment, the circuit line or the communication channel. This synchronization action occurs in much the same way, when the remote control installation uses a direct current line circuit or a carrier line circuit from the central station.

   In addition, for either of these two types of line circuits, no additional equipment other than that provided is needed in the line coding group of the central station. With proper connections to the terminals provided in the central station coding group, the synchronization circuits work equally well with either of the two types of line circuits.

   In most cases, the connections required for synchronization between the various terminals are those necessary for normal operation of the installation with the type of circuit used. Thus, the installation according to the invention provides a means for synchronizing the remote control installations using either a direct current circuit or a carrier current circuit, without requiring any additional equipment. On the other hand, the synchronization action is significantly; the same at the central post and at all the field stations for one or the other. type of line circuit.



   A single embodiment of the invention has been shown and described here, but it is understood that many modifications can be made to the insta.llation described without departing from the spirit of the invention. and without leaving its domain.


    

Claims (1)

R E S U M E Remote control installation, characterized by the following points considered individually or in combination: <Desc / Clms Page number 40> 1) It includes a central station and several stations connected by a communication channel, at least part of which is a direct current line circuit, the central station and each station being equipped with an identical coding group for transmitting and receiving selective codes between the central station and any one of the stations, a line relay being associated with each coding group and being able to occupy a normal position and a reverse position to receive a selective code and to energize the group of corresponding coding, each line relay occupying its normal position during certain periods when there is no coding action passing through the communication channel and when the coding groups are at rest; device for synchronizing the return of the coding groups to the rest position if a code is interrupted by a fault, this device comprising, at the central station, a circuit capable initially of switching the line relay of the central station to the reverse position. if it does not already occupy this position and is also capable, after a period of time chosen in advance, of switching this line relay to the normal position, another circuit for effecting the opening of the portion of the direct current line circuit during said pre-selected period in order to switch all the line relays of the stations' to the reverse position, and to then effect the closing of said circuit of direct current line. in order to put all the line relays of the stations in the normal position approximately at the instant when the line relay of the central station passes itself luff in the normal position, thus synchronizing Inaction of return to rest position of all coding groups. , ::,) The synchronization device comprises a first circuit capable initially of switching the line relay of the central station to its reverse position, if it is not already there, and also capable, after a predetermined period, of to switch this relay to the normal position in order to energize the central station coding group and bring it back to its idle state, and ' <Desc / Clms Page number 41> a second circuit to pass all the links: line stations in reverse position, then in normal position, at the end of said predetermined period, little by little. near the instant when the central station line relay itself switches to the normal position, and to energize each associated station coding group so as to return it to the idle state, thus synchronizing the return to idle of all coding groups. 3) Each code comprises a chosen number of coded signals, alternately of odd rank and of even rank, and with each coding group is associated a line relay passing in position, normal and in reverse position in response respectively to the si- even signals and odd signals of a selective code to excite the corresponding coding group, the installation further comprising a device for synchronizing the return to standby of all the coding groups if, following a fault, a code emitted by one of the stations is stopped on an even code signal, this device comprising a synchronization relay, a first circuit comprising sensitive contacts, the operation of the synchronization relay to initially switch the central station line relay to the reverse position and then to return it to the normal position, after a predetermined period, with the aim of energizing the coding group of the central station and to return it to rest, and a second circuit comprising other contacts sensitive to the operation of the synchronization relay in order to initially switch each station line relay to the reverse position and then to return it to normal position, at the end of said predetermined period, substantially at the time when the central station line relay itself switches to normal position, thereby energizing each station coding group to return it to the idle state, in synchronism with a similar action exerted on the central station coding group. <Desc / Clms Page number 42> 4) The installation includes a device for synchronizing the return to standby of all coding groups si, by following '.; of a fault, a code is interrupted on an odd coded signal, this device comprising a first circuit comprising contacts, which close in response to the fact that the line relay of the central station remains in the reverse position, this first circuit being able to make switch the line relay of the central station to the normal position after a predetermined period after stopping the code,) so as to activate the coding group of: central station and to bring it back to rest, and a second circuit comprising other contacts, which close in response to the fact that the central station line relay remains in the reverse position, and polarity change contacts occupying their active positions - while the central station line relay occupies its reverse position, this second circuit being able to initially effectively guarantee that each. station line relay occupies its reverse position and can switch station line relays to normal position at about the same time as the central station line relay switches to normal position, so as to energize each coding group. associated station and bring it back to rest, in synchronism with the. return .. to idle of the central station coding group. 5) The central station coding group comprises a chain of time setting relays or time relays responding to the alternating operation of the central station line relay and comprising an "even rank" drop relay and a drop relay "of odd rank which drops out respectively during any signal of even rank or of odd rank whose duration is greater than a predetermined short interval of the code, and the synchronization device, intended to control the return to standby of the installation, in the event that a code transmitted by one of the stations is interrupted with the central station line relay in Normal position, includes a synchronization relay, an excitation circuit intended for this relay and comprising a rest contact of the <Desc / Clms Page number 43> even row drop relay and a work contact of the odd row drop relay, a first circuit comprising a work contact of the synchronization relay to initially switch the line relay of the central station to the reverse position and to do so return to normal position after a predetermined period longer than the drop time of the odd rank drop relay, in order to excite the central station coding group to return it to the idle state, and a second circuit comprising contacts which are closed in response to the energization of the synchronization relay, to ensure that all station line relays, are in the reverse position and to switch each station relay to the normal position, at the end of said predetermined period, so as to bring each station coding group to rest in synchronism with the return to rest of the coding group from the central station. 6) The installation comprises a synchronization device for controlling the return to standby of the installation if a code is interrupted with the line relay of the central station in the reverse position, the device comprising a first circuit, comprising both an idle contact of the odd-numbered drop relay, to switch the line relay of the central station to the normal position after a predetermined period, so as to energize the coding group of the central station and make it return idle, and a second circuit comprising another idle contact of the drop-off relay of odd rank, contacts closing in response to the passage of the central station line relay in the normal position, and contacts opening in response to the switch of the central station line relay to the normal position, this second circuit ensuring that each station line relay is initially in its reverse position and being able to switch each station line relay to the normal position at the end of said predetermined period in order to energize its associated coding group and bring it back to rest in <Desc / Clms Page number 44> synchronism with the return to standby of the central station coding group. 7) The central station and each station each have EMI44.1 a group of ', codagfi, these groups being to' 4, identiqies - and capable of transmitting and receiving selective codes by the communication channel, a code transmitted by a particular station to the central station being a control code which comprises several coded signals of odd rank and of even rank, a line relay being associated with each coding group which comprises, a chain of time adjustment relays or timed relays, a polarity change relay and a relay, transmitter, the chain of time relays of the central station * comprising a bridge relay normally energized during a code and falling after the line relay of the central station has continuously occupied one or other of its positions for a predetermined period of time greater than a long coded signal, the central station transmitting relay normally not energized while the central station polarity change relay is normally energized during a check code, and The installation comprises, in combination with the coding group of the central station, a device for synchronizing the return of the installation to standby if a control code is interrupted during a coded signal of even rank, this device comprising a synchronization relay; an excitation circuit for this relay comprising a rest contact of the row drop relay ': even,' one. working contact of the odd row drop relay, and a rest contact of the bridge relay; a first circuit comprising a working contact of the synchronization relay to energize the transmitting relay; a second circuit comprising a work contact of the transmitter relay and capable of switching the line relay of the central station to the reverse position; a holding circuit comprising a working contact of the bridge relay and capable of keeping the synchronization cell energized for said predetermined period after the central station line relay has switched to positive <Desc / Clms Page number 45> reverse; a third circuit comprising rest contacts of the emitter relay, of the odd-numbered dropout relay and of the bridge relay, and capable of switching the line relay of the central station to the normal position at the end of said predetermined period in a manner energizing the central station coding group and returning it to its normal idle state; . a fourth circuit comprising work and rest contacts of the emitter relay, this fourth circuit being able to initially switch all the de'line relays of the stations to the reverse position and then be able to return them to the normal position, at the end of said period predetermined, to energize their associated coding groups and to bring them back to idle at about the instant when the central station coding group itself returns to idle, so that the return of the installation in the idle state is synchronized. 8) The synchronization device, intended to synchronize the return to rest of the installation in the event that a control code is interrupted during a signal of odd rank, comprises a first circuit comprising rest contacts of the dropout relay. odd rank and of the bridge relay and capable, at the end of said predetermined period, of 'switching the line relay of the central station to the normal position in order to energize the coding group of this station and to bring it back to the normal position. idle state, a second circuit comprising open contacts of the polarity change relay to ensure that all station line relays are in the reverse position, and a third circuit comprising idle contacts of the; polarity change relay and capable of switching every station line relay to its normal position, at about the same time as the central station line relay itself switches to normal position, thus energizing each group station coding system to return it to idle in synchronism with the return to idle of the central station coding group. <Desc / Clms Page number 46> 9) The installation consists of a central station and several stations connected by a direct current line circuit, the central station line relay being able to occupy a normal position and a reverse position, each station line relay for - being able to go into normal position when said line circuit is excited by a direct current of a given polarity, and being able to go into the reverse position when said line circuit is not excited or when it is excited with a direct current having the opposite-polarity to said given polarity, and the synchronization device provided at the central station. ,, to control the return of '. the installation in the idle state in the event that a code is interrupted by a fault in the installation, comprises a first circuit capable initially of switching the line relay of the central station to the reverse position if it is not 'not already occupy this position ,, and also capable of returning this relay to the normal position, after a predetermined period, for. to energize the central station coding group and return it to idle, a second circuit 'capable of energizing the direct current line circuit with a current of the opposite polarity, so as to ensure that all line relays' stations are in the reverse position, and also capable, at the end of said predetermined period, of energizing said line circuit with a direct current of the given polarity to cause each station line relay to switch from normal to normal position. at about the same time as the line relay of the station: central returns itself to the normal position, in order to energize the corresponding station coding group and to bring it back to idle in synchronism with the coding group from the central station. 10) The synchronization device, provided at the central station to control the return to rest of the installation in the case where a fault thereof interrupts any code, comprising a first circuit capable of initially passing the central station line relay in reverse position, if it is not already in this position, to energize the station coding group <Desc / Clms Page number 47> switch and to make the chain of time relays fall back to this reverse position condition of this line relay, this circuit comprising at certain times a working contact of the emitting relay and at other times of the feeding contacts of the relay to drop of odd rank and relay-bridge, a second circuit capable, by exciting-the line circuit with a direct current of the opposite polarity, to ensure that all the line relays of the stations are in the reverse position so as to energize the coding groups of the stations and to make them drop again, with these line relays in the reverse position, this second circuit comprising change contacts - - polarity management of the line current polarity change relay, and a circuit comprising a reverse contact 'of the central station line relay to keep the polarity change relay energized until the end of said predetermined period. II) The installation comprises a central station and several stations connected by a communication channel, at least the first part of which is adapted to powerline currents, a powerline transmitter relay being associated with the coding group of the station. central station, being normally un-excited and able, when energized, to transmit the carrier current from the central station over the communication channel, which is adapted such that each station line relay switches to the reverse position when the carrier current is transmitted from the central station, the second circuit of the synchronization device comprising a circuit for excitation of the carrier current transmitter relay.,: which includes polarity change relay contacts,. at certain times another work contact of the emitting relay, and at other times other idle contacts of the odd-numbered dropout relay and of the bridge relay, said polarity change relay contacts, being able to be controlled at the same time. end of said predetermined period to remove the excitation of the powerline transmitter relay.