DE1226166B - Joint transmission for two-way connections in telecommunications, especially telephone systems - Google Patents

Description

Joint transmission for two-way connections in telecommunication systems, in particular telephone systems The invention relates to joint transmission for two-way connections in telecommunication systems, in particular telephone systems, with a separate identification relay for each of the two subscriber stations. It relates in particular to those two-way connections in which rectifiers, which are inserted into the individual branch lines and have opposite polarity for the two subscriber stations, enable their secret traffic.

In the case of two-way connections, the subscriber stations in outgoing traffic are usually identified by marking one of the two wires of the common connecting line with earth potential. If you want to avoid the use of earth at the subscriber stations and the associated disadvantages, the principle of alternating current identification can be used for identification in the case of two-way connections of the last-mentioned type. An arrangement is known in which the windings of two identification relays are located in a starting circuit which runs over the common connecting line and the subscriber line loop and is fed by an alternating current source. Each of these windings is bridged by a rectifier and a normally open contact of the other identification relay in such a way that when the loop closes at one of the subscriber stations, only one of the two identification relays is excited by the half-wave of the alternating identification voltage for which the rectifier inserted in the relevant branch line is permeable. while the winding of the other is short-circuited for the duration of this half-wave by the bridging rectifier and then by the normally open contact of the first identification relay. However, it has been found to be a disadvantage of this arrangement that the rectifiers located between the speech wires in the idle state for bridging the relay windings are often destroyed by overvoltage.

Another known circuit arrangement is therefore used for both Subscriber places a common starting relay, which has a response circuit for the actual identification relay prepared. This fed by the official battery The circuit runs, among other things, over the one inserted in the subscriber branch line Rectifier and is therefore only effective at the subscriber station at which this Rectifier is polarized in the forward direction. The criterion is used for identification, whether the said identification relay responds or not. In the first case it takes it is the crossing of the speech wires necessary to feed the calling subscriber station and switches on the charge counters. A serious disadvantage of this arrangement is, however, that the identification relay also when a connection is established can address through a subscriber station that is currently through the non-response this relay should be marked; namely when the in the relevant Subscriber branch line inserted rectifiers as a result of damage to both Current directions has become low-level permeable. In this case, despite the crossing of the two speech wires made by the identification relay Call can be made but the wrong billing meter is being charged.

The invention eliminates the disadvantages mentioned in that in the Windings inserted over the common connecting line of the two identification relays when the loop closes at one of the subscriber stations are traversed by current in such a way that the corresponding values of the magnetic Excitation only in conjunction with additional, preferably via additional winding applied magnetic excitations that assigned to the calling subscriber station Let the identification relay take effect.

. This control of the marking relay can take place in that the marking relay in, idle state to receive a need in the fault current range, pre-excitation, and that the ffießende at loop circuit at one of the subscriber stations by the inserted into the starting current windings of both labeling relay current is directed so according to a further development of the invention, that the total excitation of the one identification relay assigned to the calling subscriber station is amplified beyond the pick-up value and that of the other identification relay associated with the non-calling subscriber station is weakened.

The arrangement can, however, according to another development of the invention also be made in such a way that the identification relays are picked up in the idle state and that when the loop closes at one of the subscriber stations through the in the Starting circuit inserted windings of both identification relays current flowing is directed so that the total excitation associated with the calling subscriber station an identification relay drops below the hold value and that of the non-calling one Subscriber station assigned other identification relay is increased.

Finally, the shared changeover switch can according to yet another Further development of the invention can also be designed so that the identification relay Step relays are that when these step relays are excited by the loop closure contacts flowing at one of the subscriber stations in the starting circuit be actuated, the additional excitations turn on, and that the resulting Total excitation in the identification relay assigned to the calling subscriber stations causes its full suit and that of the non-calling subscriber station associated other identification relay causes its complete dropout.

In all cases, the identification of the two subscriber stations is therefore always unambiguous. Since both identification relays are always effective in the event of a defective rectifier or when the handsets are lifted at the same time at both subscriber stations, this criterion can now be used in a further embodiment of the invention to initiate an alarm and in particular to prevent the establishment of an outgoing connection.

In order to change the wiring in the voting room of an exchange It is sometimes desirable to avoid shared transmissions for two-way lines to be arranged in the main distribution room. The outgoing traffic is then onward via two Facilities, for example via two subscriber circuits or via two preselectors settled. In this case, this can be done when an outgoing connection is initiated Effective identification relays the speech wires to that of the calling subscriber station through the assigned secondary device, thereby initiating its occupancy and the secondary facility assigned to the non-calling other subscriber station or lock selection. The charge counters are then in the respective subscriber circuit arranged.

Should the traffic, however, only use one subscriber circuit or only one preselector are processed, so take the two identification relays the required crossing and switching of the speech lines. The one in this Case in the common subscriber circuit arranged charge meters are included Can be connected to the counting wire via contacts labeled #relais.

For interrupting the starting circuit and for complete switching the speech wires in the communal transmission are usually provided with an isolating relay, that. when reaching a free first number recipient or when occupying a further establishment or when switching through the subscriber selection level is excited. In a further embodiment of the invention, the isolating relay in the outgoing Traffic the return of the identification relays after the connection has been released prepare in their idle state.

Is the line leading from the participant electoral level on the official side of those carrying out the switching and / or the crossing of the speech lines Contacts of the crossover relays connected to these speech wires, so prevented according to further development of the invention, the cut-off relay in incoming traffic to take effect of the identification relay assigned to the called subscriber station until it has addressed itself, so that the first to come from the participant selection level Call can reach the called subscriber station. Namely one of the identification relays effective before the isolating relay. responds, the participant selection level finds one low resistance between the speech cores. This low-resistance loop is used to occupy the subscriber loop or the preselector in outgoing traffic and is therefore interrupted by the isolating relay.

In the drawings, exemplary embodiments of the invention are shown, from which further details can be found.

F i g. 1 shows a joint transmission for two-way connections for connection to a single subscriber circuit or to a single preselector, in which the identification relays receive a pre-excitation lying in the fault current range in the idle state.

F i g. 2 shows a shared transmission for two-way connections which handles the outgoing traffic via two subscriber circuits or via two preselectors. It can be housed in the main distribution room and does not require any wiring changes in the actual voting room. The fee counters are assigned to the respective subscriber circuits or preselectors. With this arrangement, the identification relays are energized in the idle state and become effective when occupied by dropping out.

F i g. 3 shows a joint transmission in which the identification relays are designed as step relays. She has direct access to a single call finder.

F i g. 4 shows a subscriber circuit of a known ax on which the explanation of the individual arrangements is based.

A low-resistance loop at one of the subscriber stations always means the connection of a rectifier between the two wires a and b of the common connecting line VL for the respective joint transmission. If, as can only be seen from FIG. 1 , the loop closure takes place at the subscriber station Tnl, the cathode of the rectifier inserted in the branch line is connected to wire a and the anode to wire b ; the reverse applies to subscriber station Tn 2. The reference arrows attached to the individual relay windings are intended to indicate one direction of the magnetic excitation. The reference variable is the direction of magnetic excitation that occurs when the end of the winding marked by the arrowhead is connected to the negative pole of a DC voltage source or to the anode of the rectifier operating in an AC circuit.

When the loop closes at the subscriber station TnI-, the winding I of the identification relay R 1 is always excited in the direction of the arrow and the winding 1 of the identification relay R 2 against the direction of the arrow with the help of the AC voltage source WQ in all the arrangements shown; with a loop closure at the subscriber station Tn 2, the excitations are reversed.

In the case of the in FIG. The circuit arrangement shown 1 obtained both marking relay R 1 and R 2 is constantly a need in the fault current range pre-excitation via the resistor Wi and their windings II If. Lifted at the subscriber station Tnl the handset, so did the in the circuit (1) WQ, R 2 (1) , 2 t, b, G 3, Tn 1, a, 1 t, R 1 (1), WQ current flowing in the relay R 1 results in an effect supporting this pre-excitation, so that the relay Rl responds. Both partial excitations counteract each other in relay R2, so that relay R 2 cannot respond. When one of the two or both identification relays R 1 and R 2 picks up, ground potential is applied to the wire c 11c 2 leading to the line selector via the contacts 3 r 1 or 3 r 2. This results in an immediate blocking against incoming connections. The current in the winding 11 of the relay R 1 is dimensioned so that it is sufficient to hold after switching the contacts 1 t and 2 t. The contacts 1 r 1 and 2 r 1 thus switch the speech wires to a secondary device, e.g. B. to the in F i g. 4 subscriber circuit shown and thus prepare the pick-up of the common call relay R in the subscriber circuit via the contact 5 t and the thermistor HL in FIG. 1 formed low-resistance loop. The function of the thermistor HL is explained below. The call relay R in the subscriber circuit (FIG . 4) allows a free call searcher via its contact Ir in a known manner, which determines the subscriber circuit in the search run and connects it to a free first group selector. From this group selector, ground potential is then passed to wire c. In the subscriber circuit, the isolating relay TR responds, activates the speech wire a with its contact 1 tr and thus suppresses the incentive for the call seeker.

In the example under consideration, contact 3 r 1 applies earth to windings 1 and 11 of relay I.

The contact 3 r 1 closes the response circuit for the relay T. Its pick-up initially acts on the counter-excitation via the winding 11 in the circuit. opposite. This counter-excitation is now ineffective when earth potential is applied to wire c in the first group selector due to a short circuit in the winding. If the communal transmission is connected to a preselector, the negative potential on wire c disappears, and thus the counter-excitation of the relay T in the communal transmission, as soon as the preselector leaves the zero position. The same applies to those subscriber circuits in which the call relay R switches off the negative potential of the wire c by opening a break contact. In all these cases, the relay T in the circuit (2) is effectively energized, interrupts the starting circuit (1) with its contacts 1 t and 2 t, switches the speech wires through to the calling subscriber station and separates the occupancy loop for the with the contact 5 t Subscriber circuit or for the selection. The contact 5 r 1 switches the charge meter Zäl assigned to the calling subscriber station Tnl to the common metering wire z.

Completely analog switching processes take place by means of the contacts 1 r 2 to 5 r 2 when the connection is set up from the subscriber station Tn 2. The contact 3r2 causes the immediate blocking of incoming connections. The contacts 1r2 and 2r2 carry out the connection and the crossing of the speech wires necessary to feed the subscriber station Tn2.

When the connection is triggered, a new negative potential comes to wire c and causes the current in winding II of identification relay R 1 to drop below its holding value via contact 4 t and rectifier G 1. When the identification relay R 1 drops out, the circuit (2) in which the relay T was held is also disconnected. The arrangement is thus in the idle state again.

In the incoming traffic, the relay is energized via its T 1 by winding ground potential from the line selector, the speech wires on to the called subscriber location and blocks the overall Community transmission for outgoing connections.

The identification relays R 1 and R 2 are not activated. The arrangement of the contacts 1r1 to 2r2 thus prevents the line selector from finding a closed line loop or ground potential from the subscriber circuit or from the preselector via wire b to the line selector, which, as is well known, would result in an immediate disconnection of the call. The contacts 6r1 and 7r2 are to be provided in place of the direct connection shown in dashed lines if there is a risk that the response time of the relay T is greater than the time in which the call disconnection in the line selector is effective.

If the rectifier G 2 inserted in the branch line of the subscriber station Tn 2 is defective, i. H. permeable for both current directions, or when the handset is lifted off simultaneously at both subscriber locations, so to speak with a total by the period duration of the alternating voltage source WQ given time interval to both labeling relay R1 and R2. However, the thermistor HL prevented by its correspondingly sized heating time the assignment of the preselector and of the subscriber circuit during this time, and the contacts 3 r 1 and 6r2 turn a AlanneinrichtungAL. This causes a voter, in a manner not shown, to determine the joint transmission in question. The signal lamp L is switched on via the arm wl of this selector. The voter is stopped via the arm w2. The arm w3 short-circuits the windings II of the two identification relays R1 and R2 and thus causes them to drop later due to the lack of a holding current, when the loop closure is terminated at one or both of the subscribers SteRenTn1 and Tn2. The arrangement can thus return to the idle state, and the occupation attempt can then be repeated.

The in F i g. 2 works in the following way: When the battery voltage is switched on, the identification relays R 1 and R 2 are excited via their windings II and the normally closed contact g of the central relay G , which then responds itself and opens its contact g. The identification relays R 1 and R 2 continue to hold on to their windings II and the contacts 1 r 1 and 1 r 2, respectively.

If now z. B. lifted the handset at the subscriber station Tn 2, the relays R 1 and R 2 receive an additional excitation corresponding to the forward direction of the subscriber station Tn2 associated rectifier via their windings I due to the applied AC voltage source WQ in a circuit (1) corresponding circuit G 2 (see Fig. 1). In the relay R 2 this excitation is opposite to the holding excitation in the winding U , so that it drops out. The contact 5r2 blocks the subscriber circuit TS1. The contact 2r2 switches the speech wire through to the subscriber circuit TS2 and thus causes its occupancy, which is delayed by the NTC thermistor HL. (The voice wire a is already switched through via the contact 2 r 1 of the relay Rl, which is still excited.) The circuit (4) connected to the contact 3 r 2 earth, 3 r 2, 3 r 1, T (I), - for the relay T .. can not initially be efficiently because the current in the circuit (5) earth, 3R2, 3R1, T (II), R2 (III), 4R2, 6R1, c2,., - in which the relay R 2 Fault current has caused an oppositely directed excitation. Only after switching through to a free first group selector or when the occupied preselector leaves the zero position, this counter-excitation disappears, the relay T responds, switches the speech arena through with its contacts 1 t and 2t while switching off the AC voltage source WQ and disconnects with its contact 3 t off the thermistor HL. Contacts 4 t and 5 t close, contact 6 t switches .

When the connection is released, a new negative potential is applied to wire c2, so that the identification relay R 2 is in the circuit responds again, so that the circuit (4) in which the relay T was held, separated and continues to hold itself through its contact 1 r 2. The joint broadcast is now ready for a new assignment. In incoming traffic for subscriber station Tn2, the line selector applies earth to wire c2. In the circuit the relay T responds first. This turns lt connected to the contacts and 2t the speech wires of the subscriber stations by and causes the drop of the marking relay R2 by counter-excitation in the electric circuit (7) by t cancels the short circuit of the winding of III by opening its contact. 6 This measure ensures that the first call can reach the subscriber station Tn2, which is only effectively switched on as the called subscriber station due to the polarity of the supply voltage in the line selector.

If the rectifier inserted in the subscriber branch line to enable secret traffic has erroneously become conductive for both current directions due to some damage, then both identification relays R1 and R2 become effective at the same time when an outgoing connection is initiated. The contacts 6r1 and 5r2 thus cause the blocking of both subscriber circuits or both preselectors. via the contacts 3 r 2 and a 4R1 AlarmeinrichtungAL in the manner is effective, as has already been described for the arrangement of FIG. 1. After the cause of the fault has been eliminated, the two identification relays R 1 and R 2 are re-energized via their windings II and the selector arm w 1 , as a result of which the idle state of the circuit is restored.

The identification relays R1 and R2 of the joint transmission shown in FIG. 3 are step relays. With the differently directed excitation caused by the loop closure in a starting circuit corresponding to the circuit (1) , the so-called light contacts 3 r 1 * and 3 r 2 * of both relays R 1 and R 2 are actuated and switch for each relay in the circuits (8) Earth, Wi 1, R 1 (11), 3 r 1 resp.

(9) Earth, Wi 2, R 2 (11), 3 r 2 an additional excitation with the help of the windings II. That identification relay in which the additional excitation has the same direction as the excitation caused in the starting circuit can now respond completely: The relay Rl responds when the loop has closed at the subscriber station Tn 1 , and the relay R 2 responds when the The handset was picked up at the subscriber station Tn2. The contacts 1r1 or 1r2 and 2r2 prepare the connection and, if necessary, the crossing of the two speech wires a and b .

. If the connection starts from the TeilnehmerstelleTnl, the Kontakt4r1 leaves a free call viewfinder start, and this can aufprüfen c to the through-connected by the contact 5 r 1 core. The earth potential then applied to wire c in the first group selector enables the relay T to pick up in the circuit (10) earth (I.GW), 5r1, 5r2, T (I), - the relay T. the AC voltage source WQ through the speech wires and separates with the contact 4 t from the incentive for the call seeker. The contact 3t prepares a circuit in which the relay T is thrown off when the connection is triggered by counter-excitation and the two identification relays R1 and R2 by weakening their holding excitation. The contacts 6 r 1 and 6 r 2 switch the charge counter Zäl or, respectively, assigned to the respective calling subscriber station to the common counting wire z.

If as a result of a defective * rectifier in one of the participants both branch lines marking relay Rl and R2 are simultaneously effective, 2r1 and 4r2 switch the contacts to an alarm AL, as shown with reference to F i g. 1 has already been described. The lamp L is again used to signal the malfunction. The contacts 7 r 1 and 5 r 2 block the transmission immediately against incoming assignments by applying ground potential to the wire c 11c 2 leading to the line selector. The rectifier G 3 decouples the stimulus circuit for the call seeker from the circuit described above for switching on the alarm device and thus enables the contact 4 r 2 to be used twice.

When the connection is released, the earth potential disappears from wire c. Then, in the circuit (11) earth, WI 1, G 1, T is (11) 3 t, T (1), - the relay T dropped because the excitations by its two windings I and II caused opposite to each other. At the same time, the holding excitation in winding II of the identification relay Rl is weakened as a result of the parallel current branch G 1, T (11), 3 t, T (I) so that this also drops out. The dropping of the identification relay can possibly be ensured or accelerated by a counter-excitation in the indicated circuit (12) earth, Wi 5, 5 t, R 1 (111), this counter-excitation being so dimensioned that it is the in the circuit (8) weakens the response excitation that occurs up to a value that is only slightly above the required sustaining excitation.

Finally, it should be mentioned that the shared transmissions shown can also be used for two-way connections with a relay switch in the branch point. For this purpose, only the winding ends of the identification relays R 1 and R 2 connected to the alternating current source WQ need to be separated from the latter and connected to the negative pole of the operating voltage source. When an outgoing connection is initiated by connecting earth to a respective wire of the common connecting line VL, the relevant windings of the identification relays R 1 or R 2 are then effective in the same way as has already been described in detail.

Claims (1)

Claims: 1. Joint transmission for two-way connections in telecommunications, in particular telephone systems with a separate identification relay for each of the two subscriber stations, in particular for two-way connections, in which rectifiers inserted in the individual branch lines of opposite polarity for the two subscriber stations enable their secret traffic, characterized in that The windings (1) of the two identification relays (R 1, R 2) inserted in the starting circuit running over the common connecting line (VL) are flowed through by the current when the loop closes at one of the two subscriber stations (e.g. Tnl) in such a way that the corresponding values of the magnetic excitation in cooperation with additional magnetic excitations, preferably applied via further windings (H), only allow the identification relay (R1) assigned to the calling subscriber station (Tnl) to become effective (FIGS . 1 to 3). # 2. Community transmissions according to claim 1, characterized in that the identification relays receive a pre-excitation lying in the fault current range in the idle state and that the current flowing in the loop closure at one of the subscriber stations through the windings of both identification relays inserted into the starting circuit is directed so that the total excitation of the an identification relay associated with the calling subscriber station is amplified beyond the pick-up value and that of the other identification relay associated with the non-calling subscriber station is weakened (FIG . 1). 3. Community transmission according to spoke 1, characterized in that the identification relays are attracted in the idle state and that the current ffießende in the loop closure at one of the subscriber stations through the windings of both identification relays inserted into the starting circuit is directed so that the total excitation of the one associated with the calling subscriber station Identification relay drops below the hold value and that of the other identification relay assigned to the non-calling subscriber station is increased (FIG . 2). 4. Community transmission according to claim 1, characterized in that the identification relays are stage relays that when these stage relays are excited by the current flowing in the loop at one of the subscriber stations in the starting circuit current contacts are actuated, the additional excitations turn on, and that the resulting total excitation in the an identification relay assigned to the calling subscriber station causes its complete pull-in and the other identifier relay assigned to the non-calling subscriber station causes its complete drop-out (FIG . 3). 5. Joint transmission according to one of claims 1 to 4, characterized in that the simultaneous activation of both identification relays initiates an alarm and prevents the establishment of an outgoing connection. 6. Joint transmission according to one of claims 1 to 5, characterized in that each charge meter can be connected to the counting wire by the identification relay assigned to the subscriber station in question. 7. Community transmission according to one of claims 1 to 5, characterized in that each of the two partial - is contractor provide a further device (for example a subscriber line circuit or a selection) allocated to that becomes effective at initiation of an outgoing connection identifier relay the speech wires to which the connecting further device assigned to the calling subscriber station, thereby initiating its occupancy and blocking the further device assigned to the non-calling other subscriber station. 8. Community transmission according to one of claims 1 to 7 with an isolating relay, which is effective when reaching a free first Nurnmemempfänger or when occupying a further facility or when Durchschalteh the subscriber selection stage, characterized in that the isolating relay in the outgoing traffic after the connection has been triggered prepared return of the identification relays to their idle state. 9. Community transmission according to claim 8 for two-way connections, in which the line leading from the subscriber selection level officially # -sided by the contacts of the crossing relay carrying out the through-connection and / or the crossing of the speech cores is connected to this speech academy, characterized in that the isolating relay in the incoming Traffic reduces the effectiveness of the identification relay assigned to the called subscriber station until it has responded itself. 10. Joint transmission according to one of claims 7 to 9, characterized in that the occupancy wires leading to the two further facilities, via which said isolating relay is energized for incoming connections, are decoupled from one another in the idle state by rectifiers. Publications considered: German Auslegeschrift No. 1 112 132.