DE552508C - Circuit arrangement for telephone systems with dialer operation - Google Patents

Description

For telephone systems with several exchanges and dialer operation, it is known that a calling line, after it has been connected to an outgoing connection line in a certain traffic direction, is switched to an outgoing connection line in a different traffic direction if it is determined by dialing that a connection path is to be built in this traffic direction. The aim of the invention is to use the switching devices which initiate the reversal of the calling line to the greatest possible extent, to reduce their number as much as possible and, under certain circumstances, to avoid special switching devices at all. B. provided in a switching center for rerouting devices for incoming connections from each traffic direction are used, so that the number of switching devices in the exchanges is reduced, while at the same time the same devices for other switching purposes of telephone traffic (z. B. zone counting ) Can find use, which is achieved according to the invention in that a connection device arranged in the exchange of the caller, which connects a calling connection line depending on the number current impulse with connection lines of different traffic directions, from in different exchanges, eg. B. in the calling sub- exchange UVSt ₁ and the main exchange HVSt ₁ , arranged under the influence of the caller is controlled switching devices.

Figs. 1 to 7 show embodiments of the invention, namely represents the Fig. Ι the schematic arrangement of some exchanges.

In Fig. 2 of the subscriber Tw _{1 shown} in Fig. 1 sub- exchange UVSt ₁ reachable call seeker AS and .Vorwähler VW, which is used to reroute in the different traffic directions, is shown.

Fig. 3 shows a further portion of ₁ reasonable _so arranged in the sub-exchange UVSt connecting means.

Fig. 4 shows a further part of the connection device arranged in the sub-exchange UVSt ₁ and also shows the main exchange HVSt ₁ which can be reached via a two-wire connection line VL .

Fig. 5 shows part of the connection devices _{arranged in the sub-exchange UVSt 5} (see Fig. Ι). g ₀

Figs. 6 and 7 show the connections leading to the main exchange HVSt ₁

*) The patent seeker stated as the inventor:

Dipl.-Ing. Gerhard Radke in Berlin.

connection lines in another embodiment (three-core connection line).

First of all, an overview of the traffic facilities accessible to _{the subscriber Tm 1 is given on the basis of FIG.} If the subscriber Tw ₁ picks up his receiver, he reaches a group selector GW ₁ to the sub- exchange UVSt ₁ via a call finder ^^ and a preselector VW in the position ι of the preselector VW . If he wants a participant, e.g. B. Tw ₂ , the same sub- exchange UVSt ₁ , he will reach this via the group selector GW ₁ and the line selector LW _{1 of} the sub- exchange UVSt ₁ . If, on the other hand, he wishes a subscriber to another exchange, he will first switch the preselector VW to contact 2 by dialing a certain code number that causes a switchover in the group selector GW ₁ and thereby release the group selector GW ₁ in the sub- exchange UVSt _1. By this reversal of the subscriber Tm ₁ is via an intermediate ZW selector and a transmitter Ue a connecting line of the main switching center HVST _1, over which it reaches a group selector GWi in the main switching center HVST. ₁ By engaging an intermediate voter who works as a voter with free choice, it is achieved that this connection line can also be reached via other accesses. Depending on the series of impulses sent, the subscriber Tn ₁ is now either a subscriber via a group selector GW ₄ and a line selector LW _{4 of} the main switching center HVSt ₁ , e.g. B. Tn ₃ , reach the main exchange, or occupy a connection line to another main exchange via a group selector GW ^ of the main exchange HVSt _{1 in a certain decade.} Furthermore, by correspondingly influencing a device arranged in the main exchange _{+5 HVSt 1} (a follower MW in the figure), the subscriber TM! other connection routes are available. If the series of current impulses sent out is such that, under the influence of the follower MW, the preselector VW in the sub- exchange UVSt ₁ switches to contact 3, the subscriber Tm ₁ can trigger the connection devices set in the main exchange HVSt ₁ via a group selector GW ₉ and a line selector LW _S in the sub- exchange UVSt ₃ , which is connected to another main exchange, a subscriber, e.g. B. Tm ₄ , reach this sub-exchange. If, on the other hand, the series of current impulses sent out is such that the preselector VW in the sub- exchange UVSt _{1 is} reversed to contact 1, the subscriber can use a group selector GW ₁ in the sub- exchange UVSt ₁ , which may be the same as the one when establishing a connection to be set to a subscriber of the same sub- exchange group selector, a group selector GW ₂ and a line selector LW ₂ in the sub- exchange UVSt _{2 of the} same main exchange HVSt ₁ , z. B. the participant Tm ₅ , reach.

The connection options mentioned above are now based on the other figures described in more detail.

If the subscriber Tm ₁ (Fig. 2) lifts his receiver, the step relay T is excited via: earth, battery, resistor Wi, contact 1 1, subscriber Tm ₁ , contact 2 1, winding I of relay T ₁ earth. This relay initially only closes its contacts 3 1 and S t. By closing the contact 5 1 , the relay R is energized via: earth, battery, relayi ?, contact 4p, 5 1, earth. By closing the contact 13 r , the rotary magnet D ₁ of the caller AS is excited via: earth, relay interrupter RU ₁ , contacts 11 h, 12 t _v i?, R, 14p, rotary magnet D ₁ , battery, earth. If the call seeker AS has found the calling subscriber, the following circuit is established: Earth, contacts 26 v, windings I and II of relay P ₁

of the call seeker AS, c-wire, contact 3 1, winding II of the relay T ₁ battery, earth. In this circle, the relay P responds, which short-circuits its high-resistance winding II via the contact 25 p , stops the call seeker AS by opening the contact 14p , connects the wires α and b to the preselector VW via its contacts igp and 20p and connects it to the contact 4p disconnects the excitation circuit of relay R. In the circuit of the relay P current flows through the winding II of the relay T, so that this relay now also operates its other contacts, namely the separation of the excitation circuit for the winding I of the relay T takes place at the contacts 1 1 and 2 t .

After the through-connection of the tip and ring excitation of the relays A via: earth, battery, winding I of the relay A ₃ contacts 22 1 _±, IGP% -arm of the call finder AS, c-wire, subscriber "Tw ₁ , δ-wire, ü ^ -arm of the caller AS, contacts 20 ^, 2Si ₁ , winding II of the relay A ₃ contact 31 s, earth. As a result, apart from energizing relay V via: earth, contact 7 a, relay V, battery, earth, preselector VW is started for free selection by energizing rotary magnet D ₂ via:

Earth, battery, rotary magnet D ₂ , contacts 60 s, 59a, 5Si ₁ , 57 Ji, relay interrupter RU ₂ , earth. If the preselector VW has found a free connection line, which may be shown, for example, by the wires a _s , b ₃ , C ₃ , (Z ₃ , £ ₃ leading to the connection device shown in Fig. 3), a circuit is closed via: Earth, battery, windings I and II of relay T ₁ , contacts 41a, 30X, 37g, 35? I, c ₂ -arm of preselector VW, c _s -AdeT, ' thermal relay Th ₁ , winding I of relay C, head contact 64k , Shaft contact 65W ₁ earth. Relays T ₁ and C respond in this circuit. The preselector VW is stopped by opening contact 5Si _1. Closing contact 21 1 ₁ creates a holding circuit for relay A and an excitation circuit for the relays H and Y closed via: Earth, contact 24J ₁ , Re-

2ii relay 1 ", relay H, winding I of relay A, battery, earth. At contacts 23 t _t and 29J ₁ the connection line is switched _{through to wires a 3} and h _& so that now relay A ₁ (Fig. 3) is excited via the subscriber loop After excitation of relay C , a holding circuit for relay V _{1 is} closed by closing contact 67c via: earth, contact 67c, winding II of relay C, contact 69 C ₁ , ReIaISf ₁ , battery By closing the contact 6Oy ₁ , a shunt is connected to the relay C to the wire C ₃ via the resistor Wi .

If the subscriber Tn ₁ does not send out any current impulses within a certain time, the thermal relay Th _{1 is influenced} in the already described excitation circuit of the relays T ₁ and C , so that the contact 62 Ui _{1 is} closed and thus the relay 6 ¹ is excited via : Earth, contact 62 th _v 6? 3 ~ wire, da arm of preselector VW, contacts 51 x, 543 ;, 55 a, winding I of relay S, battery, earth. By opening the contact 39 s the excitation circuit of the relays C and T _{1 is} opened, so that the connection line occupied in the sub-exchange UVSt ₁ (Fig. 3) is free and the subscriber TjJ ₁ receives a busy signal via: earth, occupied, contact 30s, winding II of the relay ^ 4, contacts 2Si ₁ , 20 p, O ₁ -ArUi of the caller AS, & -Ader, subscriber Tn ₁ , α-wire, (Z ₁ -AmI of the caller AS, contacts 19 p, 22 t _v Winding I of relay A, battery, earth. During this time, relay S is held by: earth, battery, winding II of relay S, contacts 32 a, 30s, esp., earth.

If, on the other hand, the subscriber sends out number _{current impulses within a certain time, the relay ^ i 1} is de-energized intermittently, so that via a contact of this relay the driving magnets of a connection device, which is arranged in the sub- exchange UVSt ₁ and not shown in Fig. 3 (Fig . ι: GW ₁ ) can be influenced for the purpose of setting in a certain direction. When several series of current impulses are sent out, which for example consist of the digits i, 2, 3, the subscriber Tm ₁ can accordingly reach the subscriber Tw ₂ (Fig. 1) of the same sub- exchange UVSt ₁ .

However, if the subscriber 7'M ₁ wants a subscriber from another exchange, he must first dial a code number. In this exemplary embodiment, the code number may be ο. If the subscriber sends out 10 current surges, the voter (Fig. 1: Gf ^ F ₁ ) arranged in the sub-exchange UVSt _± and not shown in the figure is accordingly raised to the 10th decade. If he has reached the same, the decade contact 63 ko is operated mechanically, so that after the relay V _{2 has dropped out} , which was excited at the first interruption at the beginning of the series of impulses via: earth, contacts 67 c, 68 C ₁ , relay V ₂ , Relay V ₁ , battery, earth the following circuit is established: earth, contacts 61 V ₂ , 63 ko, £ ₃ wire, £ ₂ arm of preselector VW, contacts 49 x, 48 h, 43 X ₃ 42 q, winding II of relay U ₃ battery, earth. The relay U is in a holding circuit: earth, battery, winding II of the relay U ₃ contacts 42 q, 43 x, 46 u, 52 ^ 53 ^ earth. By actuating the contacts 35 u and 36 u , the excitation circuit of the relay T _{1 is} separated and the test circuit is prepared via the arm e _{2 of} the preselector VW. After the relay T _{1 has} dropped out, the relays H and Y also drop out, so that the rotary magnet D _{2 of} the preselector VW is excited via: earth, battery, rotary magnet D ₂ , contacts 60 s ₃ 59 a, 58 i _t 57 A, relay interrupter HU ₂ , earth, and the preselector VW is advanced to the free choice of a connecting line leading to the main exchange HVSt ₁ via a transformer Ue. It also drops out after the preselector VW is switched on, the relay A ₁ (Fig. 3), so that as a result of a short circuit in the winding II of the relay C via the contact 68 (Z ₁ n ₀ , this relay also drops out and after the contact 67 c opens The excitation circuit of the relay V ₁ opens. The contacts of these relays can then be used to trigger the selected selector (not shown) in any way. After the relay Y (Fig. 2) has dropped out, the relay X is energized via: earth, battery, relay X, contacts 45V, 46ii, 52 s, 53 ^, earth and is later held by its contact 44 x.

If the selection VW has found a free connection line (Z ₄ , b ₄₎ C ₄ , d _t via which

the main switching center HVSt ₁ can be reached, the following circuit is created: earth, contacts 86 a ₃ , 88 v _s , 84A ₁ and 85A ₂ , wire d ₄ , cü ₂ -arm of the pre "5 selector VW, winding I des relay U ₁ contacts 36 level, 37 q, 39 s, 41 a, coils I and II of the relay T _1, battery, earth. In this circuit, the relay T ₁ arrives and, after after switching through to the contacts 23 t _x and 29 t _x an excitation of the relay A ₃ has taken place via the speech loop, also the _{relay C 2} previously short-circuited via the contact 86 a ₃ to respond, so that after energizing the relay T _1, the preselector is stopped and the relays H and Y in the The already mentioned excitation of relay A ₃ takes place via: earth, battery, relay A ₃ , a ₄ wire, cz ₂ arm of the preselector VW, contacts 23J ₁ , 19 p, % arm of the call suchers ^ S ", α-wire, subscriber Tn ₁ , & -Ader, Jb ₁ -ArIn of the call seeker AS, contacts 20p, 29 t, & ₂ -Arm of the selection VW, & ₄ -Ade r, throttle Dr ₃ , earth. After the relay C ₂ has been energized, the relay V ₅ is energized via: earth, contact 89 C ₂ , winding II of relay C ₂ , contact 9Ia ₃ , relay V ₅ , battery, earth. By closing the contact 87 ^ ₅ (drag contact), a holding circuit for the relay T _{1 is} closed via the resistor Wi. After its winding I has been switched off, the relay C ₂ remains in the already described excitation circuit of the relay F ₅ via its winding II.

By sending out further series of current impulses, the selector (Fig. Ι: GWi and LW ₄ ) in the main exchange HVSt ₁ can now be set in the desired direction by actuating the drive magnets. This is done in the following way:

After relay A _{3 has} responded and before relay V _{5 is} energized, contact 97 <z _{3 is closed} to energize relay C ₃ in the main exchange HVSt ₁ (Fig. 4) via: earth, contact 98 V ₆ , 97ö ₃ , ioow ₇ , wire O ₀ , contact 105W ₁₀ , head contact 106 k _{3 of} the group selector GW \, contact 108 V ₈ , relay C ₃ , battery, earth. By closing the contact 120 c _s , the relay V _{8 is} excited via: earth, contact I2oc ₃ , relay v _s , battery, earth. By closing its contact 117 ^ ₈ , relay V _{8 is placed} in a holding circuit via: earth, contacts 117 ^ ₈₁ 118J ₁ , 11904, relay V ₈ , battery, earth. If the already mentioned excitation of the relay V ₅ in the sub- exchange UVSt _{1 occurs} shortly after the relay A ₃ has responded, the relay C ₃ drops out due to the separation of its excitation circuit at contact 98 ^ ₅ and opens its contact 120 C ₃ . Due to the current impulses sent by the subscriber, the relay A _s is de-energized in a known manner, so that the relay A ₄ in the main switching center HVSt ₁ is intermittently excited via: earth, contacts 104C ₂ , 102 a ₃ , wire _{6 of} the connection line VL, Relay A ₄ , battery, earth. The short-circuit at the contact 119 ^ ₄ is performed at the first fall of the relay A ₄ by lifting an excitation of the relay ₉ through V: ground contacts 117 z> _8, 118J _1, relay V _9, ReIaJsF _8, battery, earth; Similarly, in the sub- exchange UVSt ₁ , also by removing a short circuit (contact 91O ₃ ), the relay F _{6 is} excited via: earth, contacts _{89C 2} , 90 a ₃ , relay F ₀ , relay F ₅ , battery, earth. Both relays remain energized during the entire series of impulses and only drop out after the end of the same as a result of a short circuit via contact 119 (Z ₄ or 9Oa ₃₎ . While these relays are energized, relays V ₇ (earth, contact 92W ₀ , relay F ₇ , battery, earth) and F ₁₀ (earth, contact 114W ₉ , relay F ₁₀ , battery, earth). Due to the intermittent response of relay A ₄ in the main exchange, the group selector GW ₄ can now in any way on the desired connection line can be set to ₀ .

If the series of current impulses sent did not consist of three, four, seven or eight current impulses, the group selector GW4 is switched in a known manner by connecting its relay P ₁ via: earth, contact 113 ^ ₈ , windings I and II of relay P ₁ to the c ₇ -Arm check the connection line reached. If the same is free, the relay P ₁ is excited in a known manner and the connection line VL is switched through to the connection line occupied by the group selector GW ₄ .

If, on the other hand, the series of current impulses consisted of three or four current impulses, then the decade contact A _{34 of} the group selector GW _{4 is} actuated mechanically after the third or fourth decade has been reached. This creates the following circuit: earth, battery, resistance Wi, decade contact k ₃₄ of group selector GW ₄ , contact connection 1, 2, & _e -wire of connecting line VL, contact 101 ^ ₇ , windings I of ReIaJsIZ ₁ and H ₂ , earth. This circuit, in which only the relay H ₁ responds as a result of the weakening of the current through the resistor Wi in the circuit, is disconnected at the contact ioiz> ₇ after the current impulse series has elapsed, since, as already mentioned, the relay F _{0 at the end of the current impulse series} is de-energized and by opening its contact 92 ^ ₀ also causes relay F ₇ to drop out. Before the

Disconnection of the windings I of the relays H ₁ and H ₂ , the relay H ₁ has placed itself in a holding circuit via: earth, contacts 94C ₂ , 93 It ₁ , winding II of relay H ₁ , battery, earth. By closing contact 82Zi ₁ , relay Q (Fig. 2) is excited via: earth, battery, winding I of relay Q ₃ contacts 33 h, 34 x, c ₂ arm of preselector VW, c ₄ wire, contacts 82 A ₁ , 83 A ₂ , earth. The relay Q stays in the circle via its contact 8 q : earth, contacts 7 a, 8 q, winding II of relay Q, battery, earth. _{The test circuit running over the d 2} arm of the preselector is separated by the contact 37 g and a test circuit is prepared over the arm e _{2 of} the preselector VW by closing the contact 38 g. By opening the contact 37 q , the relay T _x also drops out, so that the rotary magnet P _{2 of} the preselector VW via: earth, battery, rotary magnet D _{2 of} the preselector VW, contacts 60 α, 59α, 58 ί _χ , 57Λ, relay breaker RU ₂ , earth is energized after relays H and Y have also been de-energized by opening contact 21 ^ _1. In addition, by opening the contact 42 q a deenergization of the relay U and thereafter by opening the contact 46 η a deenergization of the relay X. The selection VW switched on, so that first the relay A ₃ (Fig. 4) decreases, and by short-circuiting The relay C _{2 is} de-energized via the contact 90 a ₃ , so that it opens its contact 89 C _2. As a result, the relay F ₃ is also de-energized, so that the selector (not shown) (Fig. 1: GW ₄ ) is triggered as follows.

After the mechanically operated decade contact k _{34 of} the group selector GW 4 is closed, the following circuit is established: earth, battery, resistance Wi, decade contact k ₃₄ , contact connection 1, 2, contact 105W ₁₀ , head contact 107 ^ ₃ of group selector GW ₄ , winding I. of relay S ₁ , earth. The relay S _{1 is held for} a while via the contacts 115 ^ 1 and HOw _8. By opening contact 18J ₁ , the excitation circuit of relay V _B is disconnected. Another contact of this relay can now trigger the set group selector GW ₄ in any way.
The preselector VW checks via its e ₂ arm for a free connection line leading to the UVSt ₃ sub-exchange shown in Fig. 5. If he has found one (Fig. 5: a _s , b ₅ , e _s ) , a circuit is closed via: earth, battery, windings I and II of relay T ₁ , contacts 41a, 39j, 3Sq ₁ C ₂ arm of preselector VW, £ ₅ wire, winding I of relay C ₁ , head contact 67 k _t , shaft contact 77W ₁ , earth. In this circuit, the relays T ₁ and C _{1 are} energized. The preselector VW is stopped by opening the contacts 58 ^ ₁ and the relays H and F are excited by closing the contact 21 1 _1. Via the contacts 23 ^ and 29 ^ the connecting line is switched through to the wires a ₅ and b _s , so that the relay A _{2 is} excited via the subscriber loop. By closing the contact 79C ₁ , a holding circuit for the relay C ₁ and an excitation circuit for the relay V _{3 come} via: earth, contact 79 C ₁ , winding II of relay C ₁ , contact 81 ö ₂ , relay V ₃ , battery, earth conditions. By closing the contact 78 V ₃ , a shunt is placed on the wire e ₅ via the resistor Wi . By sending out further series of current impulses, 2, 2, 1, the subscriber Tm ₁ can now call the desired subscriber, e.g. B. Tw ₄ , the sub- exchange UVSt ₃ reach.

If the series of impulses sent to the connection device of _{the main exchange HVSt 1} after setting the preselector VW consists of seven or eight impulses instead of three or four impulses, the decade contact k _{7S is} actuated mechanically by the group selector GW ₄ after the impulse series has expired. The result is the following circuit: earth, battery, decade contact k _7S , contact connection 1, 2, & _e -wire of connecting line VL, contact 10 Iv ₁ , windings I of relays H ₁ and H ₂ . Relays H ₁ and H ₂ respond in this circuit and are placed in a holding circuit via: earth, contact 94C ₂ , 93Zi ₁ , winding II of ReIaIsH ₁ , battery, earth, and earth, contacts 94C ₂ , 95 h ₂ , Winding II of relay H ₂ , battery, earth. At the same time over the decade contact k _7S the relay ^ ₁ is energized via: earth, battery, decade contact k _7S, contact connection i, 2, contact 105 ^ _10, the head contact 107 ^ ₃ of the group selector GW _4, winding I of the relay I, earth. After the relay S _{1 has been} energized, the connection devices in the main switching center HVSt _{1 are} triggered in the manner already described.

By energizing the relays H ₁ and H ₂ , the test circuit running over the d ₂ arm of the preselector VW is disconnected and the circuit of the relays T ₁ and U is thereby interrupted. By closing the contact 3 5 μ, a test circuit is prepared via arm c _{2 of} the preselector VW. After the relay T ₁ has dropped out, the rotary solenoid D _{2 of} the preselector VW is energized via: earth, battery, rotary solenoid D _{2 of} the preselector VW, contacts 60s, 59a, 5Si ₁ , 57/1, relay interrupter RU ₂ , after opening contact 2ii _ä the relays H and Y were also de-energized. The preselector VW continues so that the relay A ₃ (Fig. 4) drops out. By short circuit

the winding II of the relay C ₂ via the contact 90 a _a , this relay is de-energized and, by opening its contact 89 C _2, also separates the hold circuit of the relay V ₅ . In addition, the holding circuits of the relays Zf ₁ and H _{s are} separated by opening the contact 94 C _2.

The preselector VW now checks via its c ₂ -Afm for a free connection device in the same sub-exchange UVSt ₁ . This connection device Gi can under certain circumstances be the same as the connection device shown in Fig. 3 (wires a ₃ , b _s , C ₃ , d ₃ and group selector GW ₁ ) already mentioned when setting up a connection with a subscriber of the same sub-exchange.

The connection setup will now continue in the manner already described., Whereby the subscriber Tn ₁ sets the connection device (not shown in Fig. 3) to a contact by dialing a number, digit: 2, (Fig. 3: GW ₁₎ to which a connection line leading to the UVSt ₂ sub-switching center is connected. By sending further impulse series, digits: 2, 2, 1, and the associated setting of the connection devices (Fig. 1: GW ₂ and ZJ ^ ₂ ) in the sub- exchange UVSt ₂ , "the subscriber can now call subscriber Tn ₅ (Fig 1) Reach the sub- exchange UVSt ₂ .

The release of the call seeker AS and preselector VW when the connection is released takes place in such a way that when the receiver is hung up, the relay A _{1 is} de-energized, so that after de-energizing the relays C and V ₁ by opening the contact 66 ^ _1, the relay T _{1 is} de-energized and the relays H, Y and A are de-energized. By opening the contact 2γ _α , the relays P and T are de-energized, and by opening the contact 7 _S , the relay V is de-energized. The call searcher AS and the selection VW are thus free for a new connection.

Instead of causing a reversal in the different traffic directions by actuating different decade contacts, k _si , A ₇₈ , a follow-up mechanism MW, as shown in FIG. 4, can also be used. In this case, the contact connection between points 1 and 2 is canceled and replaced by a connection between points 1 and 2 '. This arrangement then works in the following way. If, as already described, the relay A _t is energized intermittently when the series of current impulses is emitted, the setting of the group selector GW ₁₁ results in a setting of the follower MW by exciting its rotary magnet in the circle: earth, battery. Rotary magnet D _{3 of} the follower MW, Kontaktei2iw ₉ , I22ß ₄ , shaft contact 123OT ₃ , contact 125 W ₈ , earth, according to the series of current impulses sent. If the series of impulses emitted consists of three or four impulses, the follow-up mechanism is set to the third or fourth contact _{with its arm d ai} , so that after the relay V _{9 has been} de-energized, a circuit via: earth, battery, contacts 127 ^ ₈ , 126 ^ ₉ / <f-arm 31 of the follower MW of the resistor Wi, contact connection 2 ', i, & ₆ -wire of the connecting line VL, contact 10 τ V ₇ , winding I of the ReIaIsZZ ₁ and H ₂ , earth " an exciting circuit for the relay H ₁ comes about. the relay H ₂ talks, said as with the preceding description, not due to resistance Wi in this circuit in. accordingly, it is by closing the contact 82A _1, a reversal of the preselector VW to Sub- exchange UVSt ₃ , as already explained, brought about.

If the series of current impulses consists of seven or eight current impulses, the arm d _{3i of} the follower MW is after the end of the series of current impulses on contact 7 or 8, so that now a circuit is created via wire b _s in which the relays H ₁ and Address H « . By separating the contacts 84A ₁ UHdSsA ₂ , the already described reversal to a connection device of the sub-switching takes place.

Instead of using a two-wire connection line VL, a _B , b _e , in the arrangement, three-wire connection lines, a _G , b _a , C ₀ , according to Figs. 6 and 7 can also be used. The circuit operations are the same as those described above. In Fig. 6, the excitation of the relay C ₃ takes place in the same way as in Fig. 4, only that the same does not run over the wire b _e , but over a third wire c _{0 of} the connecting line VL .

In Fig. 7, the third wire C _{6 of} the connecting line VL is used to control the relays Zi ₁ and H _{2 in} accordance with the series of current impulses sent.

W ^T e have seen that each participant who wishes to speak to a subscriber of another exchange, a certain number, o, must choose. In this way, according to the exemplary embodiment, a simplification in the dialing of digits is created in that the subscriber who wants to reach a subscriber in his own exchange only dials the call number assigned to this subscriber, omitting the code digits

needs, so that an unnecessary occupancy of the connecting line leading to the main exchange is avoided. This has the advantage, especially in the case of exchanges with heavy internal traffic, that the connection is set up in the same exchange from the start without in the first place a heavily loaded line leading to the main exchange

ίο prove, and also a uniformity insofar as the subscriber goes out of his exchange for each Connection always has to choose a certain number, o, to which of course, add additional codes depending on the desired exchange.

In the exemplary embodiment, a preselector VVV was used to change direction in the various traffic directions. the Arrangement can now also be made so that two or more in parallel use lying preselection. In the case of a call, either all selection can be made be started at the same time and prepare for the different directions of traffic set or the starting of the preselector corresponding to the desired traffic direction takes place after Marking the direction of traffic.

Claims (3)

Patent claims: i. Circuit arrangement for remote Intercom systems with dialer operation and several exchanges in which a calling connection line is connected to connecting lines in different directions of traffic depending on the number current impulse B. in the calling sub- exchange (UVSt ₁ ) and the main exchange (HVSt ₁ ), arranged switching devices under the influence of the calling connection line is controlled. 2. Circuit arrangement according to Claim i, characterized in that after setting up a connection path to a second exchange in the network the switching device controlling the connecting device in the switching center of the caller arranged in this in the case of a number dialing indicating a different traffic direction, triggering which brings about the connection devices used in the second exchange. 3. Circuit arrangement according to claim i, characterized in that • after establishing a connection path to a second exchange of the Network and identification of a different traffic direction by the subsequent number dialing the connection device in the calling exchange from the switching device in the second Switching center is controlled via the speech wires. For this purpose 2 sheets of drawings