DE1223431B - Circuit arrangement for the blocking of subscriber lines - Google Patents

Description

Circuit arrangement for blocking subscriber lines The invention relates to a circuit arrangement for blocking subscriber exclusions by means of locking buttons in telephone exchanges. It's already a technique known, in which a lock button is provided for each station and subscriber circuit is used to block the subscriber line for outgoing and incoming Connections are made regardless of the switching status of the connection.

The object of the present invention is to provide in a simple manner the Blocking a connection with a blocking button on the operator console to undertake.

This is achieved according to the invention in that by actuation a lock button of the attendant console assigned to a connection via a the state of this subscriber line characterizing contact in the idle state a locking relay is switched on, which is connected to a contact in the subscriber circuit Switches on blocking potential to the test wire.

This makes it possible to block a To prepare the connection from a switchboard and depending on the To complete the switching state of the subscriber circuit. This makes it easier Way ensures that by pressing a lock button at the attendant console an existing call is not interrupted, but the blocking is still prepared will. The additional effort per connection with this arrangement is minimal and can be easily reproduced in existing systems.

According to a further embodiment of the invention, by pressing a a connection of a hunt group associated lock button of the attendant console the blocking relay when a device is in the idle state and is indicative of the idle state Contact of the subscriber separation relay switched on and this through a contact Blocking relay in the subscriber circuit, the subscriber call and the subscriber disconnection relay switched on to establish the blocking state.

According to a further embodiment of the invention, the locking relay is through contacts of the various connections of the hunt group influenced in such a way that after actuation of a certain number of locking relay contacts different connections of the collective connection switching means to prevent the Blocking of further connections of the hunt group can be controlled.

In the drawing, an embodiment of the invention is shown with the details important for understanding. The subscriber circuits TS1 to TSn and the blocking relays and blocking buttons assigned to these connection circuits are shown in the drawing. The subscriber circuit TS1 of a call station 1 ( not shown) is assigned a blocking relay Spl and a blocking button with the contacts 13SpT1 and 14,9pT1 is assigned to the operator YPI. In the drawing, two hunt groups are shown, namely the first hunt group is labeled Sal and the second hunt group is labeled Sa2. In the case of the first hunt group Sal. It is assumed that, for example, out of a total of n connections of the hunt group, only seven connections can be blocked at the same time. For the second hunt group Sa2 it is assumed that of the three existing connections no more than one connection can be blocked at the same time. If a connection is blocked more than is permitted, a signaling, for example acoustically and / or optically, is switched on in any case at the switching station. The connections that have already been blocked remain blocked.

It is initially assumed that no connection to the hunt group Sal is blocked yet. If the operator of the switchboard YPI now actuates the lock button SpT1, the relay AN1 is switched on in the following circuit by closing the contact 14SpT1: 1. 15spl, 14SpT1, Gl, ANI (11), AN1 By closing the contact 16an1, a switch-on circuit is established prepared for the relay Spl, which is closed when the subscriber circuit TSI is marked as free by Iii-der-rest position-when the contact 1 t 1.

2. +, 17tr, G2, 13SpT1, Spl, Wil, 16an1, Wi 2, -.

As long as the contact ltl is closed, the relay Sp 1 remains short-circuited and is thus prevented from being switched on. The holding circuit for the relay Spl can only exist because the contact 9spl prevents the short circuit of the relay Spl through the contact 1 t 1 via the rectifier G 3 .

By closing the contact 2spl, a circuit for the relays Rl and Tl of the subscriber circuit TSI is established. By switching on the relays R 1 and T 1 and connecting the ground potential to the cl # wire, the subscriber circuit TS1 is in the occupied state in a manner known per se. The subscriber in the subscriber circuit TS1 can no longer establish any outgoing connections and can no longer receive any incoming connections.

The blocking of the telephone station of the subscriber circuit TSI is initiated by agreement with the operator of the switching station 17P1. This arrangement is made, for example, by telephone. Such arrangements are important, for example, for private branch exchanges with many information stations, such as. B. Travel Agencies.

The blocking of further connections of the collective connection Sal takes place in accordance with the blocking of the connection for the speech station with the subscriber circuit TS1, namely by actuation of the blocking buttons assigned to the subscriber circuits and thus the connections.

By switching on a blocking relay, resistors are short-circuited in the left branch of the resistance series W73 to Win and in the right series of resistors Wil3 to. Wiln, switching on a corresponding resistor. By switching on the blocking relay Spl and closing the contact 18, yp 1 , the resistor W73 is short-circuited. By opening the contact 19spl, the resistor Wil3 is switched on. Since the contact 20an.1 is closed, from this contact via the series switching of the two resistor series Wil3 to Wiln and. Win to Wi3 the resistance value in the series connection does not change. This means that the total current in this circuit remains constant. With every further blocking of a connection line, a resistor is added and a resistor is switched off in this series connection, so that the current remains constant even with every further blocking. The voltage distribution at point U thus changes in proportion to the number of resistors in the left Z, which are connected in series, and the voltage increases with every further blocking, i.e. H. with each further short circuit one of the resistors W13 to Win. The arrangement can now be such that after the short circuit of seven resistors, resistors * in the left series connection of resistors, the voltage value at point 21 increases so that the transistor T is opened and the relay TR is switched on. The diodes Dl, D2, D3 and D4 are only provided for voltage compensation when the voltage fluctuates. This ensures that the voltage and increases resulting from the connection and disconnection of resistors are always the same size and linear.

By switching on the relay TR when the seventh connection of the collective connection 29a 1 is blocked, the lamp, LI gm switchboard M QingQsclialtet by closing the contact, 22 tr. As a result, the operator of the operator console VP1 is made aware that a further connection is not allowed to be blocked. By opening contact 17tr, the switch-on circuit of the blocking relay is disconnected in preparation. If the operator of the attendant console VPI still operates another eighth lock key, e.g. B. SpTn, there is no switch-on circuit for the eighth locking relay Spn, but it is switched on via the actuated contact 24, # pTn of the lock button and the non-actuated contact 25spn and the actuated contact 23tr of the alarm clock Wl at the switchboard and thus the operator .on is made aware of the current status.

The relay AN1 remains switched on as long as a contact of one of the blocking relays Spl to Spn is activated. The holding circuit for the relay TR is as long as at least siebeil connec- tions are blocked simultaneously. The blocking of a connection of the hunt group Sal is canceled by the fact that the corresponding blocking button is moved to the rest position. This will also cancel the holding circuit via contact 16an1 of the corresponding blocking relay.

The hunt group Sa2 is shown in the right part of the drawing. This hunt group has only three connections. In this arrangement it is prevented in a simple manner by arranging the respective not zit belonging to the connection to be blocked Spen> contacts in the claim circuit of the relevant blocking relay for the connection to be blocked that more than one connection of the collective connection Sa2 is blocked at the same time. In this arrangement the relay SP11 is switched on by closing the lock button SpT11 via the contact 26SpT11 - "if the contact 27t11 of the subscriber circuit TS11 is not actuated. This switch-on circuit does not come about even if a connection, for example TS12 or TS13, is already blocked i -.. st Tst nurunehr the struck for those Teilnelunerschaltung TS11 locked so upon actuation of a further lock key is sp via the contacts 28 11 and 29 sp the lamp L turned 11 2 at the attendant console and the alarm clock W 1 takes place. thus also in this embodiment a signaling at the switching station; when a larger number of locking keys are actuated than are allowed to be actuated at the same time.

Instead of keeping the current constant by connecting two in series Resistors each with one corresponding to the total number of connecting lines Number of resistors and with as many, each parallel to. the resistances switched contacts, which are also assigned to the connecting lines, can also Another current stabilization circuit can be switched on at point 21. One However, such an arrangement is generally more expensive than that Has arrangement according to the exemplary embodiment. In the present arrangement there is only one resistor and one contact of the blocking relay for each connection Additionally to be provided. This effort is minimal. With this arrangement is so in each case the actuation of a blocking relay assigned to a connection the corresponding resistance which shorted a series of resistors and the corresponding resistor turned on in the other set of resistors so that the total current in the Series connection of both series of resistors remains approximately constant and the one at the midpoint Voltage tapped between the series of resistors for each subsequent switch-on a locking relay rises, so that after switching on a certain number of Blocking relay Evaluation means to prevent further connections of the Hunt group take effect.

Claims (2)

Claims: 1. Circuit arrangement for the blocking of subscriber lines by means of blocking buttons in telephone exchanges, d a d urch g e - indicates that by pressing a subscriber line (TS 1) assigned blocking button (SpT1) of the switchboard via a the state of this subscriber line (TSI) Characteristic contact (ltl) in the free state a blocking relay (SPI) is switched on, which switches on blocking potential to the test wire with a contact (2spl) in the subscriber circuit (TS1). 2. Circuit arrangement according to claim 1, characterized in that by actuating a connection (TSI) of a hunt group (TS1 to TSn) associated lock button (SpT1) of the switchboard, the lock relay (SP1) when in-the-rest position belmden a characterizing the idle state Contact of the subscriber isolating relay (T1) is switched on and the subscriber call and subscriber isolating relay are switched on by a contact (2spl) of this locking relay (SP1) in the subscriber circuit to establish the locked state. 3. Circuit arrangement according to claim 2, characterized in that by contacts of the blocking relays (Spl to Spn) of the various connections of the collective connection, a stepped resistance circuit is influenced in such a way that after actuation of a certain number of blocking relay contacts of various connections of the collective connection, switching means to prevent the blocking of further connections of the hunt group can be controlled. 4. Circuit arrangement according to claim 3, characterized in that two rows of resistors are provided with a number of resistors corresponding to the total number of connections and with the same number of contacts connected in parallel to the resistors and also assigned to the connections, and that each time one is actuated A blocking relay assigned to a terminal short-circuits the corresponding resistor in one row of resistors and the corresponding resistor in the other row of resistors is switched on, so that the total current in the series connection of both resistor rows remains approximately constant and the voltage tapped at the midpoint between the two resistor rows at every further switching on of a blocking relay increases, so that after switching on a certain number of blocking relays evaluation means are controlled to prevent further connections of the collective line from being blocked. 5. A circuit arrangement according to claim 4, characterized in that an evaluation relay (TR) is controlled as a function of the number of blocking relays assigned to the connections by means of the two series of resistors as a result of adding and disconnecting resistors by changing said midpoint voltage, which the actuation of further Blocking relay prevents the connections and activates signaling at the attendant console. 6. Circuit arrangement according to claim 5, characterized in that the switch-on circuit for the blocking relay (Sp 1 to Sp n) is interrupted by a contact of the evaluation relay and the holding circuit for the blocking relay (Sp 1 to Sp n) is independent of the evaluation unit (TR) the locking relay's own contacts are established. 7. Circuit arrangement according to claim 1, characterized in that each blocking relay (Spl) can be switched on at the same time via the normally closed contacts of the other blocking relays of a group of blocking relays assigned to the terminals.