DE664177C - Circuit arrangement for telephone systems with call storage and automatic callback - Google Patents

Description

Circuit arrangement for telephone systems with call protection and automatic callback The invention relates to telecommunications, in particular telephone branch exchange systems, in which, if all lines of a bundle are busy, a storage the unsuccessful call and the automatic callback when a desired one becomes free Line is initiated.

The invention is that the call storage and the callback facility is maintained and during this call storage which is the incentive for others outgoing connections accepting facilities from the waiting point and / or the separation devices of the waiting subscriber in the exchange of Connection facilities for incoming connections can be influenced.

Due to the arrangement according to the invention, the authorized person has the right to store Participants have the opportunity to take advantage of the waiting time by holding other conversations. For example, if an extension subscriber waits for an outgoing one to become available Trunk, so he can meanwhile connect to another extension or establish a house station or another incoming public or house call receive. If the desired line that the subscriber is waiting for is meanwhile becomes free, according to the invention the subscriber receives an overlay on the conversation Sign, whereupon he hangs up his receiver and by picking up the desired one again Can initiate connection. The arrangement according to the invention is particularly advantageous Used in systems where, when the lines in a bundle are busy, the Storage of the unsuccessful call independent of switching means of the subscriber station takes place automatically, in which z. B. the license plate used to select the direction at the same time causes the incentive to accumulate the unsuccessful call. The inventive However, arrangement can also be applied when initiating waiting does not take place automatically, but through a special switching measure by the subscriber is initiated optionally.

In Figs. I and 2, an embodiment of the invention is shown.

The subscriber NBi in Fig. 2 is a for storing the unsuccessful Authorized subscriber call.

If the subscriber NBl wants an outgoing exchange connection, he presses his button SB. This creates a circuit for winding I of relay XBl: + -Pol, button SB "Contact 26tb1, winding I of relay XBl, --Pol. Relay XBl is held by its winding III: ---- Pole, contacts 27qb1, 28th1, 29xbi, winding III of relay XBi, --Pol. The circuit for the hot wire relay TH, is closed at contact 3oxb . The call seeker AS, is stimulated via contact 3ixb. Contact 32xb, prepares the test circuit The waiting state is thus only identified by the addressed relay XBi.

It is now assumed that a request AS is temporarily not free and within the waiting time there is a connection for the subscriber NB via the line selector. LW arrives. The test circuit of the line selector runs in a known manner via the isolating relay TB i. Relays XBi and RB are disconnected at contacts 26tbi and 34tbi. The circuit for relay HB is closed at contact 35tb: L: + pole, contacts 36pb1, 35tbv relay HB, - pole. The subscriber receives the usual ringing stream and answers by picking up his handset. This incoming call is ended in a known manner. It is assumed, however, that while the incoming call is still in progress, an outgoing call line becomes free, the call seeker AS, that is, sets itself to the line of the subscriber NB. In this case the relays PAi and PBi respond. The secondary buzzer circuit is closed at contact 33pbi: + pole, contact 33pb1, relay QBi, contacts 37 qbi; 38qbi, capacitor C =, subscriber station NB " capacitor C2, brush a1 of the caller AS" winding I of the relay A =, --Pol. Since the capacitors C1, C2 are in this circuit, the relay QBi cannot respond for the time being, although the receiver at the subscriber station NB has been picked up. The capacitors C1, C2 are dimensioned so that the buzzer current, which is very strong per se, is attenuated to about the volume of speech. So that the existing conversation can be continued for a while, it is advisable to switch off the buzzer not continuously, but intermittently, e.g. B. every 5 seconds to turn on.

The subscriber NBI will now give up his existing call in order to establish the desired outgoing exchange connection. So it hangs in, which triggers the connection path that exists via the line selector LW. As a result, the relay TB drops out. The circuit for relay HB is interrupted at contact 35tb1. Contact 3911b returning to the rest position closes the following circuit for relay TB,: + -Pol, resistor W =, contacts 39hbi, 4opbi, brush cl of preselector VWBi, relay TBi, --Pol. The relay TB responds immediately again, but the relay HB cannot be re-energized because its circuit is interrupted via the contact 36pbi which is in the working position. The contacts 4ihb and 4211.b have short-circuited the capacitors C1 and C2, so that now again 'the strong current to the subscriber NBi-flows. The callback is reported to him by his telephone. He's hanging again, '. As a result, the relay QBi responds in the sweeping DC circuit: -1 --Pol, Kon- '_ tt 33pbi, relay QBi, contacts 37qbi, 38qbi, 4 #ihb, partial belt position NBi, contact 4211b, brush a1 of the caller AS " winding I des Relay A =, --Pol. The wire bi to the caller AS, is switched through at the contact 43qbi. The relay QBi is maintained via its contact 44qbi: The exchange connection is terminated in a known manner. The relay PBi drops out, so that the Circuit for relay TB is interrupted at contact 4opbi. Relay HB receives a short current surge corresponding to the release time of relay TB: It can no longer respond because it is attenuated.

It is now assumed that the subscriber is making an outside call initiated an outgoing call during the waiting time (relay XBi energized) wants to hold: He picks up the receiver for this purpose, which excites the relay RB and the selection VWbi sets itself to a free connection path. That Relay TB responds. At contact 35tbi = the circuit for the Relay HB closed.

If an exchange line becomes free during the outgoing house call, it will be the same as in the event that the subscriber NB is conducting another incoming call during the waiting signal; has been described above, the relay PBi energized and the sunrmer circuit established. The summer current is dampened again by the capacitors C1 and C2. The subscriber NBI then interrupts his outgoing house call, so that the relay TB drops out and, as a result, the relay HB drops out. The preselector VWBi returns to the rest position in a known manner. In this the relay TB is energized again. If the subscriber ATBi, who receives the amplified buzzer flow via the contacts 4-, lab and 4zltb after being hung up, reports back, the connection takes place in the manner described above.

This is ensured by the relay TH; that the call storage is canceled if the desired connection is not established within a certain time. In this case, relay TH would respond via contact 3oxbi and interrupt the circuit for relay XBI at contact 28thi. The latter would in turn open the circuit for relay TH. If, in the arrangement according to FIG. 2, the call storage were not carried out automatically, but only initiated by pressing a special key, the circuit would basically not change with regard to the connections to be processed during the waiting time.

In Fig. I, the station NG is a station that is not authorized to store the call stimulus. The extension NG can initiate outgoing exchange connections by pressing the SG button.

-1 negative polarity negative polarity, button SG, hook switch of the subscriber station NG, contact 2itg, winding I of the relay XG: When you press the button, or SG lifting the handset following circuit is for the winding of the relay I XG to-civil . At contact 22x9 , earth is applied to the subscriber line parallel to the SG button so that the latter can be released again without further ado. The incentive to dial the outside line is switched on via contacts 23x9 and 2d.pg and the test circuit is prepared via contact 25x9. If no call seeker is free, the subscriber receives the busy signal in a familiar manner. He can wait with the handset to his ear until an exchange line becomes free or hangs up. In the latter case, the circuit for winding 1 of relay XG is interrupted, so that the stimulus disappears again.

In addition to the locations NBi in FIG. 2 and NG in FIG.

Claims (1)

PATENT CLAIMS: i. Circuit arrangement for telephone systems with call storage and automatic callback after a desired line becomes free, in particular for telephone extension systems, characterized in that the call storage and the possibility of calling back are maintained and during this call storage the facilities (RB,) receiving the incentive for other outgoing connections from the waiting point and / or the call disconnection devices (TBi) of the waiting subscriber in the exchange can be influenced by connection devices for incoming connections. Circuit arrangement according to Claim i, characterized in that the callback is superimposed as a buzzer on a conversation that is ongoing during the waiting time. 3. Circuit arrangement. according to spoke 2, characterized in that the same callback number is always switched on, regardless of whether the called back position is free or busy. q .. Circuit arrangement _ according to claim 2 or 3, characterized in that periodically interrupted buzzer current serves as the callback signal. 5. Circuit arrangement according to claim 3, characterized in that the callback signal is attenuated by switching means (4ilab, i.e. 2hb) in the event that the person being called back is busy. G. Circuit arrangement according to Claim i, characterized by switching means (HB) which prevent a galvanic connection from being established between the expected line and the waiting position while the waiting position is busy. 7. Circuit arrangement according to claim i, characterized in that a switching means (relay XBi) actuated when the traffic direction is selected remains automatically in the working position until it is activated by a timer (THl) or by a switching means (OB when reporting the callback) ,) is released. B. A circuit arrangement according to claim i, characterized in that when the lines of a bundle are busy, the unsuccessful call is automatically stored independently of switching means at the subscriber station. Circuit arrangement according to Claim 8, in particular for private branch exchanges, characterized in that the call storage is initiated by the switching means (buttons SB,) used for direction selection (e.g. exchange dialing). ok Circuit arrangement according to Claim g, characterized in that the call is stored only when the direction is selected by preferred subscribers (NB1). i i. Circuit arrangement according to Claim 8, characterized in that the same dialers are used to establish connections on the part of authorized and unauthorized subscribers (NB " NG) a timer (THi) is canceled. 13. Circuit arrangement according to spoke 8, characterized in that the storage ring is canceled by a timer (TH,) when the recalled party is not reported. 1q .. Circuit arrangement according to Claim 8, characterized in that the T ' The telephone of the waiting station serves as a receiving element for the callback.1 5. Circuit arrangement according to Claim 1q., characterized in that the capacitor which bridges the hook switch and which is connected upstream of the telephone tunes the callback circuit to the callback frequency.