DE3007798A1 - Modified exchange equipment for automatic reverse charging of calls - has microprocessor controlling two consecutive connections enabling automatic reverse call after attainment of specified fee - Google Patents

Abstract

The possibility exists for a called subscriber after he establishes in the conventional manner who the caller is, to decide whether he wishes to accept the fees for the call. If he chooses this option he asks the calling subscriber to replace the receiver and he does likewise. About two seconds later, the calling party receives the ring signal on an automatic basis and the fees are recorded on the fee counter belonging to the called party's line. This is achieved by equipping the local exchange (A) to which calling subscriber (Tn) belongs with equipment comprising a central identifier (H), temporary storage and number setting units (M1,M2) and a line connection unit for each subscriber (Tn). Output therefrom goes to a couple field (VK). A central processor unit (P) already used for controlling the exchange plant (A) is programmed to perform additional functions, such as storing sequentially the calling number (in store Sp2) and the called number (in store SP1). The called subscriber (Tn) has a number store (Tp), a unit fee counter (Zo) and a command push button (SE). The latter is pressed upon replacement of the receiver which sets in train the automatic dialling of the calling subscriber in the reverse direction. In a modified form, automatic call-back occurs in any case except for the last digit, that last one being sent out conditional on button (SE) being pressed. This speeds up connection recovery and excludes interference.

Description

Circuit arrangement for telecommunications switching systems,

in particular telephone exchanges with transmission of the call number of a calling subscriber via connection paths The invention relates to a circuit arrangement for telecommunications switching systems, in particular telephone switching systems, in when a connection is first established from a calling subscriber station a dialed subscriber station via the call number of the calling subscriber station the established connection path to one of the subscriber lines of the selected Subscriber station assigned memory is transferred and stored here and in which this connection is then established by triggering the connection paths involved and switching facilities is reversed, and in which with the help the stored number of the originally calling subscriber station on request of the selected subscriber, a second connection is established from the one originally selected Subscriber station is carried out to the originally calling subscriber station.

A circuit arrangement of this type is already described in DE-AS 2 311 793 known.

The object of the invention is achieved by the known circuit arrangement to exploit given possibilities to increase the telephone comfort. In particular individual participants should be given the opportunity to do something special Customer service from a large number of participants any of these participants to grant preferential connection conditions, around targeted each to give an incentive to call those individual subscribers.

The invention solves the problem posed by the fact that in dependence from the completion of the first connection setup to the final connection through-connection when reporting the originally selected participant and depending on a subsequently undertaken switching measure of the same, the second connection setup can be initiated and after it has been carried out, a transmission of billing pulses instead of the Charge pulse counter of the originally calling subscriber station to that of the originally called subscriber can optionally be initiated for this.

The invention thus creates the possibility that an originally the called subscriber can first determine who has called him, and that, depending on this, he optionally has the option of setting up the second connection when the connection established by the first connection establishment is triggered to initiate in order to thereby have the advantage of the saving of fees optionally only certain to grant to him calling subscribers, in which case he has to pay the accruing Takes over the fees itself. While in the above known case, the second Connection establishment always takes place and only if the originally called Subscriber is busy, so if the first connection establishment largely The invention sees the established connection ultimately not being established In contrast to this, a second connection establishment is only ever initiated can be reported if the originally selected participant was free and was given the opportunity to find out which-other Participant he was originally selected. Depending on that, he can then Make the decision whether to get a second Connection establishment want to initiate in order to take over the incurred call charges. So while in the known case, a second connection is only established if the selected subscriber takes place, a second connection takes place according to the invention always only under the condition of being free and reporting the original selected subscriber instead of and not depending on the busy case. Furthermore is the option according to the invention for the originally selected subscriber given, after which a second connection can take place but does not have to. This happens depending on the switching action of a corresponding switching measure of the originally selected participant.

In the drawing, an embodiment of the invention is only in Components that contribute significantly to your understanding are presented. The subsequent Description first explains the mode of operation of the specified circuit arrangement in a very general sense. The description is particularly focused below to the inventive details of the embodiment shown in the drawing the invention.

The description sets the relevant for telephone switching technology Literature as known ahead.

Please refer to the "manual for self-dialing long-distance traffic" by Prof. Dr.Ing. Martin Hebel, Franck'sche Verlagshandlung Stuttgart 1962, also on the Book Introductory Guide to Switching Technology "by Gerhard Schmitt, Verlag R. Oldenbourg MUnchen / Vienna 1965 and on the books "Landesfernwnhl I" and "Landesfernwahl II" pointed out by Rudolf Führer, Verlag R. Oldenbourg Munich 1958 and 1962.

The drawing is by two dash-dotted lines in three fields divided. Above the top dash-dotted line is a central office switch A and below the lower dash-dotted line a central office switch C. There is a long distance telephone connection between the two dash-dotted lines indicated, which leads through several telephone exchanges. Symbolic a switching network FK of a telephone exchange is indicated for this. The remote telephone connection may be through a telephone exchange or also run through multiple telephone exchanges. Details about this describe the above-mentioned specialist books in great detail.

In the telephone exchange A is a subscriber switching network TK and a connection switching network VK shown. Each of these switching fields is multilevel constructed in a manner known per se. It is also possible instead of this Switching matrices are to be provided for each WShler in several successive elective levels. The subscriber switching network Tg can also be used by the voters of a call searcher stage or the voters of both a call seeker level and a first group dial level be replaced. - The subscriber switching network TE and the connection switching network VK individually assigned setting devices M1 and M2.

On the input side of the subscriber switching network TK are subscriber connection circuits Ta and via this and via individual subscriber lines Tl subscriber stations Tn connected. The subscriber connection circuits Ta are individually with a central identifier-H in connection. The setting device Ml of the subscriber switching network TE receives its control information from the central identifier H.

On the output side to the connections of the subscriber switching network TK are connection-specific cable sets L connected to their inputs. The exits these cable sets lead individually to connections of the connection switching network VK. Outputs of the connection switching network lead partly to the subscriber switching network TK and partly to the inputs of a hierarchically higher-level telephone exchange FK. Outputs of the telephone exchanges FK lead in a manner known per se to central office exchanges, e.g. to the central office C, namely to inputs of group selectors GW. Instead of a group dial level several group choice levels can also be provided. The outputs of group selectors lead to line voters LW. Subscriber stations are via the outputs of the line selectors, e.g. Tm1, accessible via subscriber connection circuits (not shown).

The wire harnesses L are by one for a group of wire harnesses central processor P controlled.

Details about this are in the book "Computer controlled switching systems" by Peter R. Gerke, Springer-Verlag Berlin / Heidelberg / New York 1972, section 7 described in detail. Also refer to DE-PS 11 90 517 and 11 90 999 as well to DE-OS 26 02 197 pointed out.

The two speech wires (a and b) are common in wiring harness L. shown, i.e. drawn as a single-core pair of speech cores. There is also a Assignment core c shown. Switching contacts d a relay D connected, in the rest position the pair of speech wires with a receiver E is connected.

The pair of speaking wires from is on the working pages of the switchover contacts d can be connected to a transmitter S for sound signals.

The occupancy wire c is connected to one input of a gate circuit G1 tied together. This gate circuit is used to detect an occupancy on the input side of the wiring harness L. In addition, the assignment wire c with a contact k is one Relay K connected. This relay and its contact are used to feed in an identification signal.

The gate circuit G1 and the relay K are connected to the wiring harness L individually assigned addressing line ad connected. Also are at this Addressing a gate circuit G2, which has a second input at the output of the receiver for audio signals E is connected, and the relay D is switched on.

The central processor P has, among other things, a continuous and constant Rhythm rotating counter Z on.

This counter has as many outputs as there are cable sets that cooperate with the central processor P. There can be multiple groups be provided by wiring harnesses. Each of these groups works with one assigned to it central processor together. So there are just as many central processors provided, like groups of wiring harnesses L. - One of the connections of the counter Z is shown and denoted by z1. Each of these connections is therefore a cable set assigned. Each of these connections is individually via an addressing line, e.g. ad, connected to it and its corresponding wiring harness.

This addressing line leads to the gate circuits G7 and G2 and to the relays D and K.

The counter Z in the central processor P switches in a cyclical sequence and an addressing signal one after the other at regular time intervals each of the meter connections individually assigned to the cable harnesses, e.g. z1. Of the line sets served jointly by one and the same processor P. In a group, only one cable set receives an addressing signal at the same time. This addressing signal reaches the gate circuits G1 and G2 and the relays D and E. At this point it should be added that the relays are bistable. Instead of an electromagnetic relay can also be a correspondingly working electronic one Switching device can be used. A non-bistable one itself can just as well Relays are used, which via a bistable electronically operating switching device (Flip-flop) is controlled.

First, let us establish a connection without reference to described the catching process. If a subscriber at the subscriber station Tn lifts his Handset off, this causes the subscriber line loop over the subscriber line Tl closed. In the subscriber line circuit Ta is an identification stimulus formed by the in not shown and described in detail central identifier H is stimulated, the relevant subscriber connection circuit Identify Ta. The central identifier H indicates the result of this the setting device M1. This setting device does not select in detail As shown, a free line set L, which is connected to an output of the subscriber switching network TK is connected. The setting device Ml performs in a manner known per se a route search process and connects said subscriber line circuit Ta with the free line set L. The central identifier H and the setting device Ml ends its activity.

The subscriber station Tn is now via the switching network TK with the free wiring harness L connected. Included is the wiring harness of the subscriber line circuit Ta occupied via the occupancy wire c. This reassignment causes a potential shift on the occupancy wire. This shift in potential is evaluated as a signal by the gate circuit G1.

As already mentioned, the counter in the central processor switches P an addressing signal individually in a cyclical sequence and at regular intervals one after the other to each of the meter connections individually assigned to the cable harnesses. Now the line set L receives in the course of the circulation of the counter Z of the central processor P an addressing signal after the line set has been assigned, the addressing signal is received via the addressing line ad inter alia to the gate circuit G1. Because of this addressing signal and the seizure signal received from the seizure wire c is emitted by the gate circuit G1 emits an output signal. This output signal arrives via one of the line wires of the common information multiple GV to a receiving device Ap of the central Processor P. The recording device Ap is via the control line zn from the counter Z controlled. The receiving device Ap has the effect that the wiring harness is reassigned L signal from the output of the gate circuit G1 in one of the wiring harnesses L associated memory part of an information memory Sp1 of the central processor is saved. The counter Z does not only transmit addressing signals the addressing lines ad off, but also controls via the control line zn the Reception facility Ap. In itself known and therefore not in detail here As described, the occupancy signal is queried several times in succession. the end a repeated presence of the occupancy signal from a newly occupied wiring harness L it is recognized that a new assignment has taken place.

The central processor P leads after a line set has been reassigned L an identification of the subscriber station concerned. To this end, the central processor P the central identifier H to. The central identifier H is provided jointly for several central processors. The central identifier accepts the request from the central processor and connects to it. He then brings about the central processor P in the relevant wiring harness the relay K to respond. This creates an identification circuit from the central Identifier H via the central processor P and the contact k of the wiring harness prepared. This identification circuit runs over the c-wire of the Subscriber switching network TK through-connected connection to the relevant subscriber line circuit Ta. The c-wire of the subscriber line circuit is about per subscriber line circuit provided identification circuits h with provided per subscriber connection circuit Inputs of the central identifier H connected. So overall there is a Identification current path from the central identifier H via the central processor P, contact k in wiring harness L, the c wire, the subscriber connection circuit Ta and the identifier wire individually assigned to the subscriber connection circuit Ta H. The central identifier H now accepts by emitting an identification signal an identification. The result of this gives the subscriber number of the Subscriber station Tn. The identification result is obtained from the identifier H transmitted to the central processor P and here in one of the wiring harness L individually associated memory part of an instruction memory Sp2 of the central processor P saved. As a result, there is a memory part assigned to the wiring harness L in this the command memory Sp2 recorded with which subscriber station the newly occupied Line set L is connected.

After the line set L has been assigned, the subscriber receives at the subscriber station Tn the dialing character in a manner known per se. He now begins to deliver Election impulse series. These are in a manner not shown in detail from the central Processor P added and assigned to the respective wiring harness L in one his corresponding memory part of the information memory Sp1 is stored. Corresponding the recorded and stored series of dialing impulses, some of which are provided by the central Processor P are passed on to the setting device M2, forms this setting device Setting information for the connection switching network VK. If it is an iter connection, that is, a connection within one and the same central office exchange A, a connection path via the connection switching network VK becomes one its outputs established with a connection of the subscriber switching network TE is connected. In this case, further information is also used of the received selection information is output to the setting device M1, whereby a connection via the subscriber switching network TK zir selected subscriber station will be produced.

However, if the desired connection is a long distance telephone connection, so the line set L is the same via the connection switching network VK with an output connected to the hierarchically higher telephone exchange leads. From the central processor P the digits of the area code are successively and the subscriber number transmitted over the line set L. this happens in a manner known per se with the help of a bistable polarized relay, which is the same as relay D. To control that relay, setting pulses or Reset pulses generated based on control commands that are in the to the Line set L stored corresponding memory unit of the command memory Sp2 are. These control commands contain those from the subscriber at the subscriber station Tn dialed digits of the area code and the subscriber number of the dialed Participant. These digits are taken from the information store by the central processor Sp1 removed and transferred to the command memory Sp2, in each case from the the line set L corresponding memory part of the information memory Sp1 in the memory part of the command memory Sp2 corresponding to the wiring harness. The information these control commands from the memory part of the corresponding to the line set L Command memory Sp2 to the relevant relay in wiring harness L is carried out with the aid the control circuit Ar, which via the control line zn also from the counter Z des central processor P is controlled.

By means of the digits of the area code sent over the wiring harness L. become the dialers or switching matrices in the relevant telephone exchanges set. This creates a long distance telephone connection to the central office switch place C. This connection goes to the input of a connection set Vr. The following digits of the subscriber number are used for connecting through via the switching matrix KP. If a connection to the subscriber station Tm is established, the connection set Vr then gives calls to this subscriber station down and at the same time dial tone backwards over the switched telephone connection to wiring harness L. The one received in the wiring harness L by means of the receiver E. Free character is effected in a manner not shown and described in detail under Participation of the central processor P the actuation of the contact x, whereby in the Cable set off the speech wires be switched through. Lifts the Participants at the subscriber station Tm from the handset, the Subscriber line loop closed. This criterion is used by the connection set Vr recorded, whereupon he switches off the callsign and the dial tone and the Connection switches through.

A switching network KP is provided in the exchange C, through which subscriber stations can be reached. To control the mediation processes A central controller ZC is provided in the exchange C. All Processes of connection establishment via the connection set Vr to the subscriber station Tm are handled in a manner known per se with the aid of this central control ZC.

If the subscriber places at the subscriber station Tn in the telephone exchange A opens his listener again, his subscriber line loop is interrupted, whereupon in a manner known per se the entire connection up to the called Participants at the subscriber station Tm is triggered.

After previously the circuit arrangement shown in the drawing has been described in a more general way, are then the inventive Special features of the embodiment and its mode of operation are explained.

In the exchange C is also a subscriber station To provided, which is equipped with a telephone number memory Tp. Upon reaching This subscriber station gives the central control ZC a signal to the connection set Vr from, which indicates to this that a equipped with a number memory Tp Subscriber station To has been reached. - Notwithstanding this, it is also possible such a signal even when reaching other participant locations, e.g. Tm, to be given to the connection set Vr. So this can be a signal act that for the delivery of the end-of-dial indicator from the connection set Vr backwards via the established connection path.

Because of this signal, the connection set sends Vr backwards the established connection path a request signal in the form of an audio frequency signal back to the wiring harness L in the exchange A is transmitted. This audio frequency signal can be the im Pass through the entire connecting route without difficulty. It arrives in wiring harness L to receiver E. The request signal arrives from wiring harness L. via the gate circuit G2 to the central processor. This happens in a similar way Way as the inclusion of the occupancy identifier via the gate circuit Eq.

The calling subscriber cannot use the tone-frequency request signal perceive, because - as already described - the contacts x in the wiring harness L are open.

The central processor takes the request signal via the gate circuit G2 and the control circuit Ap and stores them in the line set L corresponding Storage part in the information store Sp1. The receipt of the request signal triggers the central processor obtained by the subscriber identification described and in a memory part of the command memory corresponding to the line set L Sp2 to send out stored subscriber number of the relevant subscriber station. In addition, the central processor transmits the local exchange code A. It is useful here that the digits of the area code are entered first and then then transfer the digits of the subscriber's idle number of the calling subscriber will.

For the transmission of the digits of the area code Mnd der Subscriber number Relay D is used according to the numerical values of the digits of the area code and the digits of the subscriber number become tone frequency signals from a transmitter S sent out in wiring harness L. These tone frequency signals can be series of dialing pulses or be multi-frequency code characters. (See the one already listed above Specialist literature; In the latter case it is advisable to share the wiring harnesses Assign multi-frequency code transmitters and keep them for the duration of the transmission of the To switch on audio frequency signals. In this case, the multi-frequency code transmitters receive the digit values of the named -different digits directly from the central processor P.

In this way, the area code and the subscriber numbers of the calling subscriber in the form of audio frequency signals over the line set, the Established connection path to the subscriber station To transmitted. Get from here them to their assigned phone number memory Tp. As soon as all digits of the Area code and the subscriber number of the calling subscriber through the central Processor P of the exchange A are sent out via the line set L, the central processor causes the closure in a manner not shown in detail of the contacts x in the speech wire pair. Because the subscriber station Tn only at this point in time by means of the contacts x to the established connection path is switched through, the calling subscriber is prevented from recognizing that a connection has been rerouted to a subscriber station, which is equipped with a playback device on which his subscriber number including the area code of the exchange to which he connected.

If the subscriber at the subscriber station To is thus from the subscriber called at the subscriber station Tn, the subscriber number is included Transfer the area code of the latter to the telephone number memory Tp.

The subscriber at subscriber station To has after reporting the Possibility to determine by telephone which participant he is connected to. In addition, it is also possible to change the call number of the calling subscriber his phone number memory Tp is displayed visually.

The subscriber at the subscriber station To now has the option of the remote telephone connection desired by the subscriber at the subscriber station Tn to assume the call charges incurred. He can do this through an appropriate Switching measure initiate a second connection establishment. * 3r divides - initially the subscriber at the subscriber station Tn his intention to pay the call charges to take over. He also calls the handset at his subscriber station hang up. The telephone number memory Tp is equipped with a transmission device SE. After the subscriber at the subscriber station To also in turn terminates the connection until the connection set Vr has disconnected, he gives by pressing a button on the Transmitting device SE a command to transmit the digits of the previously received Area code and the subscriber number of the subscriber station that was also received Tn. Due to this switching measure (pressing a button on the transmitting device SE) initiates a connection setup from the subscriber station To to the subscriber station Tn. This is the second connection establishment. This is done via a outgoing connection set Va in the exchange C. It passes through the telephone exchanges, which are indicated with FK. In the exchange A is a incoming Wiring harness La occupied. The second connection is still established via the Connection switching network VK, the subscriber switching network TK and the subscriber line circuit Ta to subscriber station Tn.

If the subscriber reports to this subscriber station, the is desired remote telephone connection established. The participants in the participant places To and Tn are connected to each other. The incurred for this telephone connection Call charges arrive instead of the charge counter Zn of the original call end subscriber station Tn to the charge pulse counter Zo of the originally called Participant's To. This assumption of the telephone charges for the relevant from the subscriber Telephony connection desired at the subscriber station Tn is for the subscriber can optionally be initiated at the subscriber station To.

The previously explained second connection establishment is thus carried out by a corresponding switching measure initiated by the subscriber at the subscriber station To. For this purpose, the transmitting device SE is given a corresponding command by pressing a button given for sending the stored digits; before that, however, is in the subscriber station To interrupt the subscriber line loop so long that the first Connection established connection is triggered. The second connection establishment, which is initiated by the subscriber at the subscriber station To then runs completely off automatically. For this purpose, the transmission device SE can be equipped with an audio signal receiver be equipped, which is known per se when a busy signal arrives Way tries to connect again (redial).

It is also possible to connect the subscriber to the subscriber station To assign the second subscriber line to which a subscriber station Tz is connected is. These is connected to the telephone number memory Tp. In this The second connection setup is handled via this subscriber station TZ. This is assigned a second charge pulse counter Zz. It is just as good possible, a common charge pulse counter for the two subscriber stations To and TZ to use. If the subscriber is now called at the subscriber station To and wishes If he takes over the call charges, he initiates the second connection setup So via the subscriber station TZ. The original connection according to the first connection establishment can remain until the last but one digit of the stored subscriber number is sent out. Then the subscriber at the subscriber station gives To to the subscriber at the subscriber station Tn the instruction to release the connection. After that, will at the request of the subscriber at the subscriber station To the last saved Number of the subscriber number of the subscriber station Tn sent out. Becomes the participant the subscriber station Tn then reached by the second connection, reports and the desired telephony connection is established. The accruing Call charges are borne by the subscriber at the subscriber station To. - By the last described embodiment of the invention is achieved that the subscriber station Tn is almost certainly still free if it is set up the second time is selected. A third participant hardly has the earthiness, the participant's place Tn to be used for the duration of the second connection setup.

It is also worth it,. that the transmission of charge counting pulses to the charge pulse counter Zn of the originally calling subscriber at the subscriber station Tn is terminated as soon as at least one of the two participants at the subscriber stations Tn and To interrupt the connection established by the first connection establishment.

Finally, please also refer to DE-OS 27 14 401 (VPA 77 P 6048) pointed out, which shows and describes telephone switching systems in which a Transmission of the call number of the calling subscriber to the called one Participant is provided. This is done in conjunction with an optional catch. A called subscriber can catch a subscriber calling him, i.e. he can prevent the release of the connection, and it is switched through the Connection route the call number of the calling subscriber including his area code transferred to the called subscriber and displayed here.

The invention can be very useful with that in the last-mentioned Combine the technical teaching contained in the patent application.

4 claims 1 figure

Claims (4)

Claims .1! Circuit arrangement for telecommunications rental systems, in particular telephone switching systems, in which during a first connection setup the call number from a calling subscriber station to a selected subscriber station the calling subscriber station via the established connection path to one of the subscriber lines The memory assigned to the selected subscriber station is transferred and saved here and in which this connection is then established by triggering the involved Connection paths and switching facilities are reduced again, and in those with the help of the stored number of the originally sooting subscriber station at the instigation of the selected subscriber, a second connection is established by the originally selected subscriber station to the originally calling subscriber station is carried out that is dependent on from the completion of the first connection setup to the final connection through-connection when reporting the originally selected participant and depending on a subsequently undertaken switching measure of the same, the second connection setup can be initiated and after it has been carried out, a transmission of billing pulses instead of the Charge pulse counter of the originally calling subscriber station to that of the originally called subscriber can optionally be initiated for this. 2. Circuit arrangement according to claim 1, d a d u r c h g e k e n n notices that the first time the connection is established, the calling number of the person calling Participant is transferred to the memory of the selected subscriber station before the call connection is switched through. 3. Circuit arrangement according to claim 2, d a d u r c h g e k e n n z e i c h n e t i that the call number of the call ends the first time a connection is established Participant is transferred to the memory of the selected subscriber station before a first billing pulse for this connection to the billing pulse counter of the calling party is sent out. 4. Circuit arrangement according to claim 3, d a d u r c h g e k e n n z e i c h n e t that the transmission of charge counting pulses to the charge pulse counter of the originally calling subscriber is terminated as soon as at least one of the the connection established by the first connection establishment interrupts.