DE2342429A1 - CIRCUIT ARRANGEMENT FOR A TELEPHONE SYSTEM, IN PARTICULAR TELEPHONE EXCHANGE, WITH ELECTRONIC COUPLING POINTS - Google Patents

Description

2 AUG. 197

SIEMENS AKTIENGESELLSCHAFT München 2, the

Berlin and Munich Wittelshacherx> iatz

73/6136

A circuit arrangement for a telephone system, in particular Pernsprechnebenstellenanlage, with electronic crosspoint s. ;

The invention relates to a circuit arrangement for a telephone system, in particular telephone private branch exchange, in which subscriber stations use electronic crosspoints of one or more coupling stages under the influence of a central control device for incoming connections the connection path to the selected, marked subscriber station and for outgoing connections the connection path between the calling subscriber station and through a free connection set or a marked line transmission.

In known telephone systems with electronic crosspoints, the crosspoints are individually grounded from the central one Control device controlled by marking and by means of a route search. The crosspoints once switched on remain held as long as a holding current for the individual crosspoints is available. When the connection is released, the holding circuits are disconnected. Are These electronic crosspoints are thyristors, for example, so a call is switched on and off in the subscriber circuit required because there is no direct current monitoring via the thyristors for controlling the call disconnection is possible. Such electronic components are used as crosspoints used that allow direct current to pass in both directions, for example double-directional thyristors, Triac-s, these have the property that they pass through the building a 3signalwechselstror.es vora through controlled.

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State in the rest position. This means that the speech path crosspoints at each zero crossing of the Alternating ringing current would have to be controlled again. The known crosspoint controls are not suitable for this purpose.

The object of the present invention is to control the crosspoints switched in the speech path to enable at any time without great additional effort if it is not the first speech channel cut-through.

This is achieved in that each speech path crosspoint or each crosspoint pair with an auxiliary wire and is coupled to a control coupling point located therein, that the controlled in the course of the connection route marking Control crosspoints automatically control the assigned crosspoints in the speech path and thus the connection path switch through.

In this way, the speech path crosspoints can remain controlled via the control crosspoints as long as there is a risk of an undesired speech path crosspoint shutdown in the meantime. Whenever the speech path coupling point becomes ineffective, the control coupling point in the pilot wire ensures that it is controlled again immediately. According to a further embodiment of the invention, double-directional thyristors, triacs, are provided as coupling points for the speech path through-connection, which are connected in parallel via the control coupling points located in the pilot wire, separated in coupling steps. A separate control unit is required for each speech path crosspoint pair.

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coupling point provided as a supervisor for the control.

An exemplary embodiment of the invention is described with reference to the drawings.

1 shows a private branch exchange with a switching matrix with from triacs ,. as double-directional thyristors, existing crosspoints.

Pig.2 shows a private branch exchange with a switching matrix with coupling points consisting of opto-triacs. These components, known as opto-triacs, are used here consist of two triaes (double-directional thyristors) controlled by a light-emitting diode, v / obei the triacs in the Speech wires and the light-emitting diode in the pilot wire are located.

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Pig.3 shows the integration of the exemplary embodiments according to Pig.1 and Fig. 2 in a private branch exchange an overview. Pig.4 shows the application of the so-called "rate effects" in Pig.2. The subscriber station is in the PBX shown on the basis of Pig T1 via the connecting line VL and the switching stages A, B, C of the switching network KP, for example with the connection set VI connected. The coupling field shown consists of triacs, as double-directional thyristors, which have the property to pass both direct current and alternating current. But with each zero crossing of the alternating current, these triacs are switched off. In order to be able to switch these triacs through each time they are switched off, the additional c-wire with the crosspoints is necessary coupled via the assigned thyristors. A permanent control circuit should be provided via this c-core at least until the connection is switched through exist in such a way that the triacs after each zero crossing of the alternating current, for example the ringing alternating current, can be activated again.

The fork-hold contact is in the idle state of the subscriber station 1GU in the rest position and there is no loop to the connection set. If the subscriber now lifts the receiver at subscriber station T1, in this way this fork changeover contact 1GU is actuated and the normal connection is established via the contacts 2nsi and 3nsr connected in parallel Loop with the prescribed resistance value, which is recognized in conventional systems in the subscriber circuit and whereby the connection establishment to the connection set either through the initiation of corresponding, directly controlled selectors or with the initiation of identification or /. after scanning by a scanner with subsequent identification and a Marking the path adjustment is made.

The system according to the present exemplary embodiment is based on a completely different principle. At a central point (AT) the addresses of the subscriber stations for which an incoming or outgoing connection already exists are stored.

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Based on this, the central controller AT cyclically prepares the connection to a
freely marked connection set. This cyclical connection of all subscriber stations with this free and provided connection set takes place until a subscriber station is connected to a connection set in the cycle mentioned, which is currently issuing an input assignment for the establishment of an outgoing connection. This is recognized by the loop status evaluator AW ^ of the connected connection set. This evaluator AW. is assigned to the Α side of the connection kit. If this subscriber station is then finally connected to the connection set provided, ie if this connection set is now also centrally marked as occupied, a new connection set is made available as free and successively with the in the cycle mentioned
Subscriber stations that are not yet centrally marked as occupied in a memory (of the AT) are connected. If all connection sets are busy, either an exchange line or an auxiliary set is provided and used in a known manner. _ψ

In this way, a subscriber circuit is unnecessary, since
if, for example, the subscriber of subscriber station T1,
who has lifted the receiver and has established the loop via the contact 1GU in the above-mentioned manner, connected to the connection set V1 in the aforementioned watch-through cycle from the central control device via a correspondingly set path via the switching stages A ₁ B and C of the switching network KP and as Caller is recognized. This is because it is now being monitored by the switching devices of the evaluator AY /. the closed loop of subscriber station T1 is determined and, since a scanning cycle is running for this subscriber station, that is, an existing connection does not exist, causes the connection established to remain in place. The dialing character is transmitted on the basis of this status identification.

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Me triacs of the switching matrix KP through which the path is switched remain from the c-core at the dialing alternating current envelope passage switched through.

The dialing codes now issued by the subscriber station are, by appropriate matching of the resistance values of the resistor R2 looped in by opening the contacts 2nsi and 3nsr, with the resistance values of the resistor R1 and the transformer U in the form of current reduction indicators, for example half the current in the evaluation means of the connection set cause, transferred. This reduction in current does not trigger the triacs connected in the speech path. When the first pulse is received, the dialing signal is switched off in the connection set in a known manner. The signals received by the selection receiving means choice identifiers are also evaluated there or centrally and run in "a known manner via the central control means for adjusting the connection to be established path is this way set., The evaluator checks AW _B in the connection set which is assigned to the B-side, The loop status of the connected, desired subscriber station. If the loop is open, then the call connection takes place. If the loop is closed and the subscriber is already busy, the call connection does not occur because the evaluator AW _B recognizes the loop closed In the occupancy memory, the B-through-connection is omitted from the start and a busy code connection is made on the Α-side.

If the earth button is actuated during the existing connection, this indicator is also here in a known manner, since one of the speech wires is short-circuited, in the connection set on the A side assigned evaluator A? /. recognized. When you hang up the handset is the current value again equals zero and this is also determined by the evaluation means of the connection set evaluated and leads to the release of the occupied crosspoints and other facilities, in particular of the connection set.

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From the above, it can be seen that the subscriber station T1 identifies with full current, with hold current and with zero current value be transmitted. This "means that a distinction between select and trip flag zero current value, i. a distinction between the dialing code and the release code does not have to be provided, so. that the monitoring of the pulse length is thus also superfluous.

From the above it can also be seen that both the signaling, as well as the call feed and call shutdown, the latter takes place in the connection set for incoming connections. This is possible because the triacs work as bidirectional thyristors and accordingly the current in let through in both directions. However, this is subject to the restriction that at each zero crossing of the alternating current the Triacs are switched off. To ensure, however, that the triacs of the connected speech wires after each · zero crossing of the alternating current immediately through again, is the c-wire with the auxiliary wire crosspoints assigned to the speech wire crosspoints, consisting of switched through at least until the called subscriber station is reported via the transistor Thyristors, provided.

It should also be mentioned that there is a control for the control of the coupling points to be controlled due to the route search these crosspoints both in the mentioned cycle and in the case of targeted control for an incoming connection anyway necessary is. This control takes place via the mentioned Thyristors, which are in said pilot wire c. In this way, the control points for the crosspoints are multiple used to control the triacs in the speech cores. In this c-wire there is also a switching element, for example the Transistor T present, which when reporting to prevent a Speech transmission via the c-core is to be blocked. This c-core is guaranteed from the time of activation to at least The called subscriber reports the control of the transistor assigned to the connection set and thus the maintenance

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Maintaining the connection path and control of the triacs independently whether the triacs are temporarily switched off by alternating current signals or not. The voice alternating current has on holding and dropping the triacs has no effect, because this one is superimposed on the triac holding current.

These triacs still have the advantage that they are self-protecting because only at a higher voltage above, for example, 400 V, that is more than 6 times the operating current it is possible to destroy these elements. It must be assumed, however, that every subscriber station receives overvoltage protection. This means that the system is sufficiently fail-safe.

When there is an incoming connection, the connection is switched through by marking the desired extension. In this case, the extension is controlled specifically and the The call is switched off depending on the person recognizing the loop Switching means in the B-side evaluator AWt, of the connection set.

The above-mentioned transistor T, which is located in the c-wire in the connection set, is blocked after the called subscriber station has been reported or after the outgoing connection has been established, ie after the time after the AC signals from the speech wires are safely switched off in order to reduce the risk of galvanic coupling and thus of crosstalk. If an alternating current signal has to be switched on during an existing connection, the c-wire must be coupled through both to the calling subscriber station and to the called subscriber station, which is possible without additional effort, because the "occupied path is because the speech wires are still are switched through, as are the participating participants themselves, still known.

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If the earth button is pressed during an existing connection, it is, for example, a recoupling to another connection set necessary.

When pressing the earth key, the relevant subscriber station T1 is over > da3 switching network KF, for example, connected to an anti-transmission.

This earth key is pressed in the A-side Ausv / erter AW. established, because in a well-known way, one of the speech veins, e.g. the b-vein, is de-energized. As a result, the Triaes in this Ineffective grounding of the core. To turn these triaes back on immediately, the c-wire must be switched through again. Because of this- is the connection set, here e.g. an address memory ASp assigned to the exchange transmission for the recording of the address of the Α subscriber.

The crosspoints of the c-wire and thus the crosspoints in the relevant mentioned speech artery can now. can be controlled and switched through again. After releasing the earth button and again The c-core can be released again by switching through the said speech vein. .

By pressing the earth key mentioned above, if the recoupling is not takes place via a switch in the transfer of office, the original Connection path can be triggered from the exchange transmission and a recoupling to an internal connection set in known Way can be initiated from the central control device. The new setting of the connection path is done by due to the stored participant address and the stored transmission address the crosspoints of the c-wire determined by the route search and thus the corresponding crosspoints of the speech wires are controlled v / earth. The original? / Eg remains in connection with the subscriber and trunk transfer address in a special '

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Memory .stored. In this way, through appropriate, .ox calling ^

"known measures the originally γ subscriber station or the Queryed subscriber station is connected to the originally occupied trunk transfer and is thus connected to the waiting subscriber will.

If the switching takes place on the inquiry path in the exchange transfer itself, so. During the inquiry, the path to the transfer of the office can be made remain.

Both when the exchange connection is withdrawn by the A-subscriber, as well as when transferring the trunk connection depending on one When the B-subscriber presses a button, the one called speech artery is interrupted and takes place by pressing the earth button As described above, for the initiation of the inquiry, the reallocation of the interrupted speech artery in which the c-artery is described controlled again and the corresponding crosspoints controlled there. Purely the renewed setting of the A-side pilot wire is the said address memory ASp for the Aufnahae Addresses of the Α-participants and for the connection of the B-side Connection through the c-core of the address memory BSp is provided for receiving the address of the B-subscriber. After renewed activation At the crosspoints of the speech wire, which was de-energized by pressing the earth button, this auxiliary wire is released again.

In the system described with reference to FIG the use of the triacs is not only used to switch the calls on and off from the connection satζ, which is the case when using Thyristors is not possible, because there the call activation and deactivation must take place individually from the subscriber circuit, but can also include the complete subscriber circuit and the galvanic isolation it contains to decouple the Direct current from the thyristor crosspoints can be saved.

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As already mentioned, this is achieved in that in the system described, the subscriber stations are cyclically connected to a set of connections that are marked as free and made available and are checked for the loop status in such a way that this is only possible for those in an occupancy memory as freely marked participant positions. This occupancy memory is designed in such a way that either the address for identifying this occupied state is written in with the occupancy identification or, what is more expedient, an occupancy identification is written to subscriber addresses already present in a certain sequence and is deleted again when it becomes free. this cyclic switching through a \ ^r provided Getting Connected record with unassigned subscriber stations is an easy way for parallel exploitation of a successive continuity test and for functional testing of the directional finder, the coupling points of the paths. For this purpose, it makes sense to successively switch through connections between a marked connection set and the free subscriber stations according to a scheme adapted to the functional test in order to deliberately control all connection options, crosspoints and Y / Ege in this way.

Are in the circuit described above according to the embodiment In Fig. 2, the newly developed opto-triacs are now used instead of the triacs, i.e. are in the speech cores Triacs switched, which are controlled by LEDs connected in the c-wire, this has the advantage that during the existing Connection a separation of the c-wire to avoid a galvanic coupling is not necessary, because these X-light-emitting diodes do not have the property of galvanic coupling. This also means that the existing connection path is via the c-core remains continuously stored and, in contrast to the exemplary embodiment according to FIG. 1, address memory for receiving the A subscriber address and the B-subscriber address in the connection records

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and aints transmissions in which an earth key identifier was added and evaluated can be omitted (ASp and BSp).

The control of the speech wire crosspoints, triacs, assigned Auxiliary wire crosspoints, thyristors, and thus also the Light-emitting diodes take place in the embodiment shown in Pig.2 again via the central control device and the path finder. As in the exemplary embodiment according to FIG. 1, here too the cyclical switching between one marked as free Connection set and a subscriber from a certain sequence defining the connection! and the occupancy status beforehand to carry out testing central scanning device J "*. The other Processes correspond to the processes that have already been carried out using Pig1. described have been.

From the overview in Figure 3 it can be seen that the above Scanning device contains a connection set and trunk markers VM and a subscriber marker TM, the connection set marker always set to the next free connection set and the participant marker successively controls the free participants. This control is as mentioned depending on the subscriber's occupancy identifier, which is recorded in the occupancy memory BSp. This occupancy identifier takes place, for example, by writing an allocation bit to the respective subscriber address. Y / ird is the central control device occupied for another process, this scanning process can continue regardless of this, only if a path setting of the central control device is made, the cyclic subscriber scanning process is to be interrupted, which the central control device caused by a corresponding command to the scanning device AT.

In Fig. 3, both the control of the internal connection sets KVS and the control of the Aints transmissions AVS at +) of the central control device (AT)
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its activity as an auxiliary sentence "indicated when all connection sentences are occupied.

In Figure 4 is a for the embodiment according to Pig.2 another type of connection path through-connection shown without path search according to the so-called "rate effect".

In an article by the International Telephon and Telegraph Corp. in the journal Telephony, December 6,1971 is the exploitation the aforementioned "rate effect" based on various exemplary embodiments for switching through a speech path described via PNPiI modes. This description shows that differ from the multitude of possible connection paths due to the properties of the named PNPIi diodes and the different timed connection automatically a route as preferred Path results when you mark the start and end point of the connection to be switched through. At de.r in the article mentioned described arrangement is the so-called single-core speech path through-connection.

In the arrangement according to Pig. 4 the marking of the c-wire at the starting point and at the end point by identifying the connection set via the VSK and marking a subscriber made via the scanner ATK and this c-core switches through according to the so-called "rate effect" when the marking Completed depending on the pre! identification of the subscriber station was. This means that an overvoltage first occurs via a corresponding indication point IK of the subscriber station the c-core is determined and the marking circuit for this subscriber station in the control only if the voltage remains normal AST is soaked and the c-core is coupled through in the manner and way mentioned will.

After switching through one of the possible connections between the connection set and the subscriber station via the corresponding PNPN diodes Dl, D2 and D3, the LEDs LD1, LD2, LD3 also control the triacs Ta1, Tb1 and Ta2, Tb2 and also

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Ta3 and Rb3 causes. After this through-connection, the c-wire remains switched through for the duration of the connection and the processes run according to those described with reference to Pig.2 and Fig.1 Operations. In this embodiment, too, there is a special A address memory and B address memory for storing the corresponding participant addresses and the renewed activation of the b-core when pressing the earth button is not necessary. The saving of the Path searcher and the saving of the occupancy memory for the identification of the respectively occupied subscriber positions costs this arrangement according to Figure 4 an additional indication point each Attendees. But this is what the connection path through-connection is for faster, v / as is beneficial for the time required is to perform a scan cycle of the subscriber parts. The connection set is designed in the same way as for the embodiments according to Pig.1 and Pig.2.

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Claims (5)

Patent to s g ϊ ^ ° ^ £ Circuit arrangement for a telephone system, in particular Telephone private branch exchange in which subscriber stations have one or more switching stages via electronic crosspoints under the influence of a central control device for incoming connections the connection path to the selected, marked Participant parts and the connection path for outgoing connections between the calling subscriber station and a free connection set or a marked line transmission switch through, characterized in that each speech path coupling point or each coupling point pair is coupled to an auxiliary wire and a control coupling point located therein that the in the course of the connection route marking dxxrchgesteuerten control crosspoints automatically control the assigned crosspoints in the speech path and thus the connection path switch through. 2. Circuit arrangement according to claim 1, characterized in that for the speech path through-connection Double-directional thyristors, triacs, are provided as crosspoints, which are in the pilot wire lying control crosspoints, separated by coupling stages, switched on in parallel. 3. Circuit arrangement according to claim 1, characterized in that the control of the control coupling points is carried out by means of path search and marking. VPA 9 / 61o / 3167b - 16 - 509813/0424 4. Circuit arrangement according to claim 2, characterized in that said control coupling points consist of electronically controllable elements such as thyristors, PNPN modes and the like, the assigned, double-directional thyristors, triacs, in the speech cores both during connection establishment, as well as with each zero crossing of a signal alternating current applied to the speech path. 5. Circuit arrangement according to claim 2, characterized in that the connection set is a Auxiliary wire disconnecting switch is assigned. VPA 9 / 61o / 3167b 509813/0424 Blank page