DE664112C - Circuit arrangement for telephone systems - Google Patents

Description

Circuit arrangement for telephone systems It is known in telephone systems when establishing connections to occupied connection points the intrusion on bring about these connection points by applying a potential to the connection path. If the same potential is now also used to initiate other switching operations, such as e.g. B. Inquiry connections or transferring trunk connections in private branch exchanges, is used, the connection is all with the switching means for connection of this Potential-equipped participants possible.

The aim of the invention is to enable connection to existing connections by applying a certain potential then only certain connection points practically to enable if there are more connection points that the connection using the effecting potential to initiate other switching processes, and achieved this in that the switching means in the exchange through a connection the intrusion potential applied by the calling station during the test period initiate and by locking means if the connection was made before or after the test period the connection is prevented at the same potential.

The arrangement according to the invention achieves that a connection by participants who have the switching potential to initiate other switching processes is available, e.g. B. the ground connection. practically prevented via the speech arteries is, as an intrusion by a subscriber by pressing the earth button only succeeds if the participant in the short, only millisecond test time of the voter's earth to the speech wires. If the ground connection is already taking place before or after the test time, the connection established is released.

An exemplary embodiment of the invention is shown in the drawing. This is a private branch exchange in which internal connections run via the call searcher AS and the group selector GW and the line selector LW . Outgoing exchange connections are established via the call searcher AS, group selector GW and the exchange line AL . Incoming exchange connections are indicated to an extension officer by the incoming call flow over the exchange line; the officer switches the apparatus BA to the calling exchange line AL , accepts the request of the calling office subscriber and then causes the setting of the call seeker AS to the calling exchange line AL and also the setting of the group selector GW and the line selector LW. If the officer leaves z. B. their place during the night; by turning the night switch NS, the night station NSt is identified as a night station. This passage is connected to a Atntsanrüfjs via the exchange line with the anrufendon. "Trunk in arrival and then their f hand the trunk call at any given extension subscriber to forward. Now, if a connection routed through the official BA or through the night position NSt to a busy subscriber, so immediately after the output of the series of current impulses, namely in the time in which the test potential is temporarily applied to the switching arm c of the line selector, the connection of earth potential via the speech wires of the connection path, which has the effect when the line selector LW is set , that a connection Establishing an internal connection If, for example, the subscriber Tit wants a connection with the subscriber Tn, then when the handset is picked up at the intercom Tja, the caller AS is set to the caller in a known manner Sending out a certain street The group selector GLT1 is set to the specific group of hundreds of the desired participant. After this setting, the relay is energized via the following path: earth, battery, winding I of relay r1, contacts i o; 2 na, winding I of relay D, contacts 3 1i, 4 b, switch arm.a of group selector GW, switch arm a of call seeker AS, via the subscriber loop of subscriber Tit, switch arm b of call seeker AS, switch arm b of group selector GW, contacts 5 b, 6p ,, winding II of relay 0, winding II of relay A, earth. Relay A responds in the aforementioned circuit; the relay O is a differential relay which is not energized in the aforementioned circuit. The relay A closes the contact 7 a. The relay C responds. A series of impulses is now sent out to set the line selector LW to the series of contacts to which the desired subscriber is connected. The interruptions generated by the number switch of the calling station are transmitted to relay A. Relay A drops out according to the interruptions and influences the following circuit: earth, contacts S o, g p, winding I of relay Z ', contacts ioc, iia; i 2 u, shaft contact i 3 w, lifting magnet H, battery, earth. The relay V remains; v excited during the series of current impulses, If the relay L 'drops out after the series of current impulses, the following circuit for the relay U is closed: earth; Contacts 8 o, g p, i: Iv, head contact i 5 1z, contact i6 c, Wick - ", ilng I of the relay U, shaft contact 1 3 w, stroke ° 't% ägnet U, battery, earth. In the above Only the relay U is energized, while the lifting magnet H remains unaffected. Relay U causes the switchover from lifting magnet H to rotary magnet D by opening contact i2 it and closing contact 17 it Impulse series is transmitted to the rotary magnet D. The circuit runs via: earth, contacts 8 o, g p, winding I of the relay T ', contacts 1ö c, iia, i7it, rotary magnet D, battery, earth. Relay i' is also during of the series of impulses excites and during this time the contact 14v opens, so that the circuit for the relay U is interrupted via the winding I. However, the relay U is kept excited during the actuation of the rotary magnet by the series of impulses transmitted via the following path: earth, contacts i8 c, ig v; 2o11, winding II of the relay is LT, contact 2 1 p; Battery, earth. If the relay V drops after the end of the series of impulses, the contact igv is opened and the holding circuit via the winding II of the relay U is interrupted. However, relay U only drops out some time after relay V. When relay TV has already dropped out, but relay (j) is still energized, test potential is temporarily applied to switch arm c of line selector LW via the following path: earth, contacts 22c, 23v, 2411, windings II and I of relay P, relay P ,. switch arm c of the line selector LW in the position of the subscriber to be called via subscriber relay T2 of the desired subscriber Tia .. to battery, earth: If the subscriber Tn. is free, relay P can respond. Relay P closes contact 25p and blocks by shorting the High-resistance winding II of the relay P the called subscriber in a known manner. Relay P closes the contacts 26p and 27P and prepares the ringing circuit. After the relay U has dropped out, the following circuit is established for the winding II of the relay Y ': earth, relay breaker RU, contacts 281t, 29 y, 30p, winding II of relay L ', battery, earth, relay h is energized at certain time intervals by the relay interrupter and thereby turns dur ch opening the contact 31 v and closing the contact 32v following ringing circuit: From the ringing current source R, contacts 32v, 33P, winding I of the relay Y, contacts 26p, 34.P ,, switching type na of the line selector LW, via the alarm clock on the Subscriber station Tn. ,, switching arm b of the line selector LW, contacts 3 5p1, 27p, winding II of relay Y, winding II of relay 0, earth. If the called subscriber answers, relay Y is energized during the pause and opens the circuit for relay L 'at contact -2gy. There is now the following supply circuit for the called subscriber: Earth, battery, winding I of relay O, contacts 31 v, 33 p, winding I of relay Y, contacts 26p, 3 ¢ h, switching arm a of the line selector LW, via the loop of the Participant Tiz., Switch arm b of the line selector LW, contacts 31 h, 27 p, winding II of relay Y, winding II of relay 0, earth. The relay 0 is not energized in the aforementioned circuit because it is connected differentially. The connection between the subscribers Titl and Tn. Is thus established: If the subscriber Tn. Is busy, the relay P cannot respond during the test period in which relay V has dropped out, but relay U is still energized. After drop of the relay, the relay B is U: earth contacts 93 pi, 94u, B relays, contact 95n2, shaft contact 58w, p contact 21, battery, earth energized. Relay B opens the circuit via relay A at contacts .I b and 5 b. This causes feed bridge relay A to drop out and, with contact 7 a, to open the circuit of relay C. Relay C drops out. A circuit for the rotary magnet D is established via: earth, contacts 8 o, c) p, 1d.1 ', 1510, 36c, 37-1-s, rotary magnet D, battery, earth. The rotary magnet D actuates the contact 38d, so that relay U about: earth contacts Thus, 9p, id.v, head contact 15) z, contact 38 d, winding II of the relay U, contact 21 p, battery, earth is energized. U relay breaks the contact 37 is the circuit for the rotary magnet D. The rotary magnet D is de-energized, opens contact 38 d azn the circuit for relay L%. The relay LT drops out and closes the contact 37u again. The last-mentioned circuit for the rotary magnet D is established again. The rotary magnet and the relay U work together as a self-interrupter until the line selector LW has reached the rest position in which the head contact i 5k is opened. This means that no circuit for rotary solenoid D or relay U can be established. The subscriber receives a busy signal in some way and hangs up the receiver. The facilities taken into use go back to the rest days. The release of the line selector LW after the call has ended is initiated after hanging up the receiver at the calling station and thus the relay A drops out in the manner described above. Establishing an outgoing exchange connection If the subscriber Tizl wants a connection with the exchange line, the call seeker AS is set to the calling subscriber in a known manner by lifting the receiver. By sending out a certain series of impulses, the group selector GW is set to a series of contacts through which the exchange lines can be reached. The group selector Gll- 'seeks in free choice one of the free trunk lines, z. B. AL, from. After the trunk line AL has been occupied, the following supply circuit exists for the subscriber Tyal: earth, battery, winding I of relay S, winding I of relay X ,,, line 39, switching arm a. of the group selector G61 = ', switching arm'a of the caller AS, via the subscriber loop of the subscriber Tnl, switching arm b of the caller AS, switching arm b of the group selector GW, line do, winding II of relay X2, winding II of relay S, earth. Only relay S responds in this circuit. Relay X., is a differential relay. The series of impulses sent by the subscriber are picked up by relay S and transmitted to winding III of relay J through contact 41 s. The relay J gives the current impulses through contact .I2 i on the trunk line AL. During the series of impulses, relay l'1 is via contact .43 i and relay L '. excited via contact d..Ivl. Establishing an incoming exchange connection If an exchange call comes in via the exchange line AL , the relay AR is energized. Relay AR turns on a call signal for the officer in a known manner not shown. The officer then operates the interrogation switch, whereby the device BA of the officer is connected to the exchange line by opening contacts io6as and 107as and closing contacts d.5as and q.6as. The officer accepts the request of the calling subscriber and then flips the connection switch, which, with its contacts 47v and 48v, sends the BA's apparatus via the already open contacts ioi as and 102as and the closed contacts I9 as and So as to the Call seeker AS turns on leading line 5i-52. This causes the call finder AS to be set on the line S, 1-52 in a known manner, not shown. The officer now sends out current surges via the line 51-52 by means of a current impulse transmitter, through which the group selector GW and the line selector LW are set. During the series of impulses, contact 35 ns is closed in some known manner and thus relay E is also energized. The relay E closes the circuit for the relay El via contact 54e. When the relays E and Ei are excited, the connection to earth via the contacts 55e and 56e is interrupted. When the series of current impulses has ended, relay E first drops out and, when relay Ei is still temporarily energized, applies earth to line 51. This ground connection does not trigger any switching processes when the group selector GW is set.

1 after a line selector LW has been assigned, but the group selector GW is set to the specific contact group by the following series of impulses of the line selector LW. The setting of the line selector LW is carried out in the same way as already described for establishing an internal connection. After the end of the series of impulses on the part of the officer, the earth connection is temporarily carried out by relays E and El. This energizes the differential relay 0 in the line selector LW , but cannot trigger any switching operations since the selector has not yet turned in. The relay O drops out again after the temporary earth connection.

After setting to the specific contact row, the officer sends out the last series of current impulses, through which the line selector LW is set to a specific contact of the selected contact group. The switching processes that are caused by the last series of impulses are the same as those described for establishing an internal connection. After the end of the series of impulses, the contacts 55e and 56 ei are again temporarily connected to earth, namely during the time in which the relay L 'in the line selector LW has already dropped out, but the relay U is still energized. The differential relay Q is excited by the ground connection.

If the subscriber to whom the line selector LW is set is free, relay .P responds during the temporary test period in which relay V has dropped out, but relay U is still energized, and causes the described above when establishing an internal connection Switching processes, such as blocking, switching through, calling, etc.

If, on the other hand, the subscriber to whom the line selector LW is set is not free, the relay P cannot respond and the following holding circuit is used for relay 0. established: earth, winding III of relay Q, contact 57q, shaft contact 58w, contact 2 1 P, battery, earth. Furthermore, after the end of the temporary test time and thus the relay U has dropped out, relay B is energized via: earth, contacts 93h, 94u, relay B, contacts 95m, 58 w, 2 ip, battery, earth. The contacts 59 q, 6o q., 99q and zoo q are closed by relay Q, so that the calling officer is connected to your occupied subscriber via this and the contacts 96b and 97b closed by relay B and this is connected to the presence of the present Outside call can make notification. The called busy subscriber will then terminate and release his existing connection. After this, the relay P can now respond via the distributor switch VS, which prevents double checking, and the folded contact 61 q and initiate the switching processes already described, such as switching through, calling, etc. Relay P interrupts the holding circuit for relay Q at contact 2 i P. Relay Q returns the contacts to the rest position. The connection to the desired subscriber is now established in the same way as if the subscriber was free when the call was made. Inquiry connections If there is an exchange connection between a calling subscriber and the external line AL , the calling subscriber can initiate an inquiry connection by pressing his Tal key. By pressing the button, the difference relay X in the supply circuit is excited, which acts with contact ro5 x2 'on a switching device Z shown schematically, in such a way that by temporarily pressing the button, a switchover from the exchange line AL to the line 62-63 by opening the Contacts 64z and 65z and closing of contacts 66z and 67z is brought about. By closing the contact 69 z, the impulse contact 42i is short-circuited, so that subsequent current impulses sent by the inquiring subscriber are not transmitted to the exchange line AL, but via the closed contact 68 z, throttle Dr, and impulse contact 69i to the line 70-7T, to which a call seeker AS has adjusted when switching by the device Z. The group selector GW and the line selector LW are set by the series of impulses in the manner already described for internal connections: During the series of impulses, the relays hl and Tl2 are energized. A ground connection via the contacts 72v2 and 73 v1 does not take place, since the relay P2 is not energized and thus the contact 74P2 is also open when the subscriber makes inquiry connections. If the inquiring party wishes to reconnect with the exchange line AL after the inquiry call has ended, the switching device Z is acted upon by pressing the button again via relay X2, which switches over from the lines 62-63 to the exchange line AL by opening the contacts 66 s and 67 z and causes contacts 641- and 65s to close.

However, if the subscriber called in the inquiry, z. B. the subscriber Tn2, take over the outside call, he presses his button Tat, whereby the difference relay 0 lying in the feed circuit of this subscriber is energized. Relay 0 applies earth to one voice wire via contacts 75 o, 6p1, while opening contact 1.o and closing contact 760 creates a holding circuit for relay A, disconnecting the voice wire. By connecting to earth via contacts 75 o and 6p1, the differential relay X1, its circuit via: earth, battery, choke Dr, winding I of relay X1, contacts 77 v, 691, choke Dr2, contacts 78v2, 79N, winding II of the relay X "Throttle Dr, earth runs, energized. The relay X1 acts with contact 103x1 on the switching devices U, Ui shown schematically. This influences the switching device Z in such a way that the switching from the lines 62-63 to the exchange line AL is initiated and furthermore the exchange line AL is connected to the line 70-71 by opening the contacts 8o a1, 81 u and closing the contacts 82 it 8.3 tc. The requested subscriber is thus connected to the exchange line AL the connection path via the call searcher AS and group selector GW is separated in a manner not shown on the part of the inquiring subscriber ückfrage accepting subscribers in turn establish an inquiry connection, the earth criterion is transmitted to the differential relay X by pressing a button, which acts with contact 104x on the switching device Z, through which the switchover from the exchange line AL to the lines 62-63 takes place. Since the contacts 8,411 and 85 ui are open and the contacts 86u1 and 87U1 are closed, the inquiry connection is established via the lines 51-52, call seeker AS, group selector GW and line selector LW . The current surges are transmitted in a manner not shown from the subscriber Tii, via the line selector LW, group selector GW, call seeker AS to the winding II of the relay J, which passes the current surges on to the lines S1-52 with contacts 69i.

After termination of the inquiry connection, the person making the inquiry can initiate switching back to the exchange line or the subscriber called in the inquiry can take over the exchange call. If the latter is the case, the connection path is the same as when an incoming exchange connection is established. Night connections If the extension officer is e.g. B. not at the place during the night, the night switch 11'S is turned over, whereby the telephone station NSt is marked for receiving exchange connections. If an outside call comes in via the outside line, the relay P2 is energized by energizing the relay AR via contact 88 ar Holding circuit for relay P2 via contact 9o s is completed. Relay P2 has switched through the voice line to contacts 91p2 and 92p2. The night station NSt is now connected to the exchange line AL and can accept the call and, if necessary, forward it to another desired intercom by the intercom NSt in the same way as with outgoing exchange connections establishes an inquiry connection, after which the subscriber called in the inquiry calls the exchange call can take over the manner described. When setting up the inquiry path through the night station NSt, a connection option is also provided if the subscriber called in the inquiry is busy. The series of current impulses sent by the telephone station NSt are picked up by relay S and transmitted to winding III of relay J. Relay J actuates contact 69 i, so that the current impulses are given to the inquiry line 7o-71. During the series of impulses, relays V1 and V2 are energized, and relays P2 are also energized for connections to the night station NSt. As a result, after the end of the series of current impulses, during the time in which the relay h1 has already dropped out, but the contacts of the relay V2 are still in the working position, earth is connected to the contacts 74P2, 73 v1, 72v2, 68z, 85u the line 71 is applied, whereby the differential relay 0 in the line selector LW can be excited, namely after the last series of impulses in the temporary test time of the line selector, in which the relay V has already dropped out, but the relay U is still energized. In this way, the connection to a busy subscriber is initiated in the same way as when an incoming answer connection is established, which is forwarded by the officer.

Preventing the intrusion through the call stations equipped with an earth button If the subscriber Tn has established a connection to the subscriber Tyz and the subscriber Tn is busy, the intrusion by the subscriber Tnl is prevented in the following way: Is the test time of the line selector LW terminated, ie relays V and U have already dropped out, a circuit for relay B is connected to earth; Contacts 93pi, 94 U, relay B, contact 95 in, shaft contact 58w, contact 2z p, battery, earth established. Relay B opens contacts 4. b and 5 b and closes contacts 96 b and 97 b. As a result, the speech wires are interrupted, the ground connection on the part of the subscriber Tat, cannot act on the differential relay Q, and the relay A drops out. This opens the circuit of relay C through contact 7a. Relay C drops out, and the line selector Lfh 'is triggered in the manner already described.

If the subscriber Tazl presses the Tal button during the series of current impulses, relay 0 is energized, but the following circuit is established as a result of the intermittent actuation of relay A when relay A has dropped out for relay M: Earth, contact 98r, winding 11 of the relay IYT, contact 57 g, shaft contact 587v, contact 2z p, battery, earth. Relay M responds and interrupts the circuit for relay A at contact 2 m. Relay A can no longer be excited by the subsequent current closure. Relay A remains de-energized, and when contact 7, a is opened, relay C also de-energizes. The line selector LW is triggered in the manner described.

Only if the participant Tzz succeeds in just a few milliseconds to bring about the earth connection during the test time of the line selector LW a connection to a busy subscriber is established. But this is practical locked out.

Claims (1)

PATRNANT CLAIMS: r. Circuit arrangement for telephone systems, in which for connection. authorized and unauthorized call stations are equipped with switching means for connecting the same potential to initiate different switching processes, characterized in that the switching means (O-relays) in the exchange initiate a connection through the connection potential applied by the calling station during the test period and by blocking means ( Relay 11, 7, B) if the same potential is switched on before or after the test time, the connection is prevented. a. Circuit arrangement according to claim i; characterized in that the potential causing the connection is applied via the speech wires. 3. Circuit arrangement according to claim ä, characterized in that for the purpose of switching off ground potential is applied via the speech wires. 4. - Circuit arrangement according to claim i, characterized in that a controlled by pressing the number switch of a civil servant contact (53fzs) affects the effective during the temporary test period of a voter (E dropped out, Ei energized). 5. Circuit arrangement according to claim r, characterized in that the call station (NSt) marked for monitoring connections during the absence of a civil servant (NSt) are assigned switching means (relay P #.), Through which a connection of the potential causing the connection to an existing connection takes place via the contacts of the devices active during the temporary testing period of a voter (V, dropped out; V, energized). 6. Circuit arrangement according to claim z, characterized in that only during the temporary test time of the selector (LW) by switching means (relays III and B prevented from responding) a switching state enabling the connection to an existing connection is established. 7. Circuit arrangement according to claim 6, characterized in that an energized in the test time, the connection causing relay (O) prevents the triggering of the selector which occurs in Verbiredangen without connection to occupied connection lines and maintains the connection path. B. Circuit arrangement according to spoke 6, characterized in that in the event of an activation incentive (earthing the speech wire) that takes effect before the test time, the activation relay (D) initiates the triggering of the selector (LTV). G. Circuit arrangement according to Claim 6, characterized in that the dialer is triggered (by relay h ') after the end of the test time beyond the gate, there is no intrusion incentive and the called connection point is busy.