DE959117C - Circuit arrangement for telephone extension systems - Google Patents

Description

(WiGBl. P. 175)

ISSUED FEBRUARY 28, 1957

T 1135 VIII a / 21Φ

Karl Giermann, Kassel

has been named as the inventor

(Ges. Of 15.7.1951)

The invention relates to a circuit arrangement for telephone private branch exchanges in which a outgoing exchange connection is initiated by a switching measure of the extension and incoming>. Office connections can be determined by a manually operated workstation. For It is known for such private branch exchanges to provide a dialer to each trunk line for a connection to the trunk line, so that as long as trunk lines are free these can be seized by the extension for an outgoing exchange connection. Are however, fewer voter facilities are available than there are trunk lines, so it can happen that a calling extension does not have an exchange line when all dialer systems are busy can prove, although some are still available.

The invention eliminates this deficiency in that when the exchange number is indicated by a calling Extension unit dependent on the occupancy status of all dialer devices and the occupancy status of the available trunk

gene identifying switching means display means for the individual identification of the relevant, a Activate the outgoing exchange connection at the operator console. According to Further features of the invention are the identification of the extension by different Influencing the extension lamp already provided for other purposes via that of the Extension individually assigned contacts,

ίο effective while all external lines are busy switching means switch on a busy signal for the calling extension.

In telephone systems in which telephone subscribers have dialer equipment assigned to them To receive access to attendant consoles, it is already known when these attendant consoles are occupied or the connecting lines leading to these places special call organs, which are assigned to the individual positions

ao to switch on a special place, so that this special place possibly the connection in question manufactures. For this purpose, the individual voting devices have an overflow position equipped, when all others are busy

& 5 exits is reached and gives access to the connecting organs of the special place and to the display organs of this place. Since basically all traffic is handled by hand in these systems, the operation of the special place as well as the operation of the other workstations must in any case enter a calling subscriber line so that the further connection can be established. A display is also made at the special place in question if the special place cannot meet the connection request of a subscriber due to the fact that all available further lines are busy.

For private branch exchange systems of the type identified above, this could thus be known Arrangement does not give any suggestion on how to handle the outgoing official traffic without too much hassle in the number of electoral institutions and without a stronger noticeable relief for the civil servant can handle so that even if all dialer devices that have access to the Establish trunk lines, even the extension itself from manual connection establishment does not find out anything.

An embodiment of the invention is shown in the drawing. The drawing shows in the middle the extension line with the relays R and T assigned to it, lamp TL, jack TK and button Ta. On the right is the access to the central office, while the one to the dialer for connection to an exchange line is on the left. The relay R is a step relay, the contacts of the first step have the index I, while those of the second step have the index. to lead. Only the parts necessary for the invention are shown for switching the exchange line, dialing device for an outgoing connection to the exchange line and for the house control center.

The following switching processes occur in detail:

House traffic ^ 5

The house traffic of the extension T runs in a known manner via the house record, call seeker AS and line selector LW.

Outgoing official traffic with free

Dialer device for the connection

with an outside line

If the extension T wishes to establish a connection to the office, it picks up its receiver and briefly presses the Γα key. In this case, if the connection set of the house control center has not yet accrued, the relay R is activated in its second stage. The first stage of relay R is actuated via the line loop. Contact rl 4 has no effect. Contact rs ι puts the winding II of the relay R and the relay T to the contact c of the selector AAS of the selector device for connection to an exchange line. Contact rs 3 places the stimulus relay AnA of the dialer in the loop circuit to the calling extension T, so that the relay AnA is activated . Contact rs 2 prepares the switching on of the lamp TL for the individual identification of the extension T. However, this circuit cannot take effect because there are still trunk lines free. The relay AnA of the selector device stimulates the selector AAS to adjust to the calling extension T in a known manner. Relay R is held in the first and second stage by its winding I in the line loop. At the same time, it is also caused in a known manner that the exchange dialer AW selects a free exchange line. The attitude of these voters is known per se and therefore does not need to be illustrated and described in more detail. If the selector AAS finds the connection of the calling extension T identified by contact rs 1 , the relay T of the extension connection in the test circuit also responds. Contact 1 3 indicates that the extension T is occupied by switching on the lamp TL. The contact part and i2 open the stimulus loop circuit to the selector device; the relay R , however, remains in the test circuit via its winding II. If the office selector AW of the voter no device has found a free exchange line, the extension can establish its connection in a known manner. If the house connection set with its dialer AS was already on the connection of the calling extension T before the office identification, the relay X of the house connection set is activated by applying earth with the Ta key. Contact χ ι separates the P call circuit for connecting the extension T , so that the relay T comes to waste and the relay R is switched to the second stage via the line α of the extension T by the plus of the Ta key. The further processes take place as indicated above. The relay R speaks in its second stage only when an outside line is identified by the extension T.

via the line α . II via the winding of the relay R can address only the first stage, while both stages are held via the winding of relay R II. The release of the exchange line and the occupied dialer takes place in a known manner when hanging up the extension T by opening the line loop.

Outgoing exchange when busy

of all voter liaison facilities

and trunks still free

If the extension T wants to occupy a free exchange line and all dialer devices are occupied, the relay BS via the line loop of the extension T comes to respond via the chain connection of the contacts bell of an unillustrated receipt relay of all dialer devices. To seize an exchange line, the extension T operates its key Γα in a known manner, so that - as already described above - the relay R is activated in its second stage. Contact rs 1 cannot take effect because there are no more voter facilities available. Contact rs 3 switches on a relay BS via the chain connection of the incentive line of all dialer devices and via the line loop of the extension T. Contact bs 1 places the interrupter U via the contacts ba ^, rs2, * 3 to the lamp TL, which is assigned to the extension T individually.

From the flickering of the lamp TL , the operator recognizes that the extension T wants an exchange connection and that all dialer devices for the connection to an exchange line are busy. The officer leads the connection plug VSp of a free exchange line into the jack TK of the extension T and connects the calling marked extension with a free exchange line. The extension T noticed nothing of this manipulation by the officer. Via the line c of the pawl TK , the relay T comes into effect in a known manner and therefore not shown and, with the contacts ti and i2, separates the relay R from winding I and the relay BS . Contact 1 3 switches off the different identification of the extension and identifies it as occupied by continuously switching plus to the lamp TL. The relay R drops its armature in the first stage. Contact rl 4 has no effect. The extension can now establish its connection to the desired subscriber in a known manner. The exchange connection is released after the final signal has been given, which - as it is known - · is not shown. The officer pulls the plug VSp of the exchange line from the jack TK of the extension T. By opening the line c , the relays R and T are switched off. The extension T and also the exchange are ready for a new assignment.

Outgoing official traffic on busy signal
all trunk lines

If all trunk lines are busy, the relay BA is switched on by the chain connection of the contacts b 11 and bill of the receipt relays (not shown) of all trunk lines. Contact bai switches the busy signal BezA to the relay BS, which is transmitted to a calling extension T after its office identification via the contacts baz, rs 3, resistance Wi, contact 12, line loop, contact 11, relay R winding I. The busy signal is only switched on if all exchange lines are busy, contact ba ^ prevents the individual identification of the extension T at the operator console if all dialer devices are busy.

Incoming official traffic

Incoming official traffic takes place in a known manner by lighting up the call lamp and queries the operator, who then puts the connection plug VSp of the exchange line into the jack TK of the desired extension and thus forwards the connection of the calling exchange line to the desired extension. These processes are known per se and are therefore not shown in more detail.

Claims (2)

Patent claims: Make the first circuit arrangement for telephone private branch exchanges, in which, by switching action of the extension going to be set voters facilities which is interconnected _g5 tie a calling extension with a free intended for outgoing traffic trunk while incoming trunk calls are mediated by a manually-operated workplace and where the number of trunk lines available for outgoing traffic exceeds the number of available dialer equipment providing access to these trunk lines, characterized in that, if there are free trunk lines serving the outgoing traffic, despite the fact that all dialing equipment intended for the outgoing traffic is busy (AAS, AW) in the case of the outside line identification (earth key after lifting the handset) by a calling extension on the occupancy status of all dialer devices (AAS, AW) dependent switching means (BS) and the occupancy status of the available trunk line gene identifying switching means (BA) switch on display means (TL) for the individual identification of the relevant, an outgoing exchange connection requesting extension at the switchboard. 2. Circuit arrangement according to claim 1, characterized in that the identification of the extension takes place through different influencing (flickering) of the extension lamp (TL) already provided for other purposes (occupancy display) via the contacts (rs 2) assigned individually to the extension. 3 · Circuit arrangement according to claim ι, characterized in that the switching means (BA), which becomes effective when all the trunk lines are busy, switches on a busy signal (BezA) for the calling extension. Relevant publications: German Patent Nos. 228 903, 257962, 277234, 302679, 582205, 611 929, 645 533, 684775, 617559 1 sheet of drawings © 609 808 2.57