BE384791A - - Google Patents

Description

       

   <Desc / Clms Page number 1>
 



  "IMPROVEMENTS TO TELEPHONE SYSTEMS". The present invention relates to telephone systems in general but more particularly relates to long distance switching devices for long distance traffic in systems of this type. The aim of the invention is to simplify switchboards, switching devices and methods of operation, in order to enable long-distance operators to establish and control connections more efficiently than is possible to do with current equipment.



   According to the current way of operating, all the interurban switching devices for a given urban network are centralized on an interurban switchboard.

 <Desc / Clms Page number 2>

 bath which usually comprises arrival positions (said B positions), self-propelled positions (called A positions) and positions serving circuits with waiting times (called C positions), the number of positions of each category depending on the amount of traffic to be provided. Operators standing in "B" positions answer incoming calls from other urban networks, and these calls are transmitted directly or are transferred to a "C" position to be completed later.

   Transit calls, that is, calls in which the switchboard serves as a tandem switching point, are received at positions "B", in principle in the same way as incoming calls.



  In the case of originating long distance calls, the calling subscriber will ordinarily request a special number to obtain the call with an "A" position. The attendant will set up a record for the call, and complete this call directly, or move the record to a "C" position where 1 + call will be completed later.



   The trunk switch board, which forms part of the present invention, includes. the position arrangement described above, but keyboard controlled intermediate trunk circuits have been provided in place of the usual cord circuits to interconnect the subscriber lines and the auxiliary lines.



   One of the features of the invention has been an arrangement to prevent the connection of a trunk line with an auxiliary line until the connection through the auxiliary line has been completed. This arrangement prevents the erroneous sending of signals through the battery return line and earth from the switching device used to establish a connection. An incoming call can be transferred to another position before it is answered by the operation of the key to release the trunk circuit taken by the calling line.

   It is provided, automatic ringing devices with the help of which, when ...

 <Desc / Clms Page number 3>

 as calls originate from certain positions, inrush current is automatically applied to the called trunk line or to the subscriber line, and hand-operated callback devices are also provided for these positions.



   The invention is also characterized by a provision for indicating the group to which a calling line belongs, which is particularly advantageous in a system using automatic distribution of calls, as is the case in the present system.



   The invention is further characterized by an interurban transmission selector, which disconnects the battery and the earth of the auxiliary line, when establishing a connection with a subscriber line, which it disconnects. either free or busy, or when all the auxiliary lines in a group are busy. The transmission selector pulse relay is connected to the control wire or 4th wire to give line seizure control, and this relay is kept energized in this circuit until it is disconnected when answers the call, so that its release provides answer control. A backward call switch is also provided to allow an operator in position "A" to call back a subscriber without releasing the original connection.



   The invention will be better understood from the description given below, with reference to the accompanying drawing, comprising Figures 1 to 13.



   In this drawing:
FIG. 1 shows an individual pulse transmitter for an operator, of the keypad type.



   Figure 2 shows the telephone set and attendant apparatus provided for each "B" position.



   FIG. 3 shows a junction circuit combined with the operator's apparatus of FIG. 2, as well as an incoming trunk circuit and its associated preselector

 <Desc / Clms Page number 4>

 associate.



   FIG. 3A represents a junction circuit associated with another position "B n, and an interurban circuit with its associated preselector.



   FIG. 4 represents an interurban selector associated with the trunk circuit of FIG. 3.



   FIG. 5 shows the telephone set and the attendant apparatus provided for each "C" position,
FIG. 6 represents a connection circuit associated with the operator apparatus of FIG. 5.



   FIG. 7 shows a long distance transmission selector accessible to various long distance selectors.



   Figure 8 shows a combined trunk line connector for city and trunk service.



   FIG. 9 represents a junction and transfer circuit associated with the operator apparatus of FIG. 5.



   Figure 10 shows the telephone set and attendant apparatus provided for each "A" position.



   Figure 11 shows a junction circuit for annotation, combined with the operator apparatus of fig.



  10, as well as a subscriber line, a line switch, and an urban selector.



   Figure 12 shows a rear return switch associated with the position device of fig.10.



   Figure 13 is a diagram showing how the various boards of the drawing are to be put together.



   In fig 1, the KS keypad includes ten digit keys, an ST start key, and an ER error key. Each time a key is actuated, the corresponding digit is formed in the logger, which, along with the associated transmitter shown in schematic form, can be of any suitable type.



   In fig. 2, there is shown an operator's telephone headset OT, a position device PA and a

 <Desc / Clms Page number 5>

 dial D, which are provided for each position "B", The position device is permanently associated with a number of junction circuits which are connected to this device, one at a time, by the lowering of the answer keys of the junction circuits, as a result of which the conversation conductors of the junction circuit are locked by the device, with the telephone headset connected as a bridge. Call keys and secret listening keys K1 and K2, of the type with two working positions, are provided and arranged to lock in the fixed position only when they are brought into the listening position. secret.



  A release key K, with automatic return position, is designed to allow the release of partially established connections without releasing the associated junction circuit. The position device is normally combined with the device
 EMI5.1
 entagistreur-sender of fig- 1, by contacts of the key K20, while the dial D can be connected if necessary by the key of dial K20. The recorder-sender is connected to the position device when the switch is operated, while the dial is connected following its first movement out of the normal position.

   The dial connection is maintained automatically until a connection is established and, during this time, a dial control lamp L lights up when the position device is so arranged that a pulse d. the call is automatically transmitted for all calls established in position "B". Keys K1 and K2 are only required for callback and for certain control operations.



   In fig. 3, there is shown a junction circuit L combined with the position apparatus of FIG. 2 and comprising a listening and monitoring key K3, a release key K4, a line lamp L2, an occupancy lamp L3, and a supervision lamp L4. A se-

 <Desc / Clms Page number 6>

 The reader (Fig '4) is individually permanently associated with trunk circuit L. Trunk circuits, such as L, are accessible to preselectors, such as LS, which terminate incoming trunk lines.



  The lines coming out of the preselector banks are distributed over the various "B" positions, as shown. In the scrubber bench 338, the odd contacts are multiplied and connected to the L1 lamp, while the even contacts are multiple and connected to an L20 lamp at a different position. The corresponding contacts of this bank are multiplied for the preselectors of all the interurban lines of a group, that is to say the interurban lines coming from the same urban network. Each group of trunk lines will be arranged in this way, and an identification lamp corresponding to each group will be provided at each position.

   Thus, the lamp L19 is a group lamp for the group of trunk lines comprising the line shown in fig. 3A. Bell relay 301 is permanently bypassed on the auxiliary line in series with battery and earth, but since the winding connected to the battery has extremely high resistance, it does not act. to actuate the relay, and this arrangement is provided simply so that the negative line conductor continues to be live, which reduces the disturbance due to the accumulation of dust on the contacts of the relays.



   Fig. 3A represents a preselector LS2 and a junction circuit L3 which are analogous to those shown in fig. 3. The trunk line ending with the LS3 preselector is assumed to be in a different group than the trunk line shown in fig. 3.



   Fig. 4 represents an interurban selector S associated with the junction circuit L of FIG. 3 this selector is of the well-known type with vertical movement and

 <Desc / Clms Page number 7>

 rotary, comprising a fourth wiper to establish a supervision circuit, and it has access to inter-city lines, to transmission circuits in positions "C" and to a series of inter-city switches placed in levels four, two. and three, respectively.



   Rod 5 represents an operator's telephone set, OT1, a PAL position apparatus and a dial D1 provided for each "C" position. This device is similar to that of position "B n, shown in figure 2, except that a numbering device transfer key K7 and a collection control key K8 have been provided, the first being used because of the ruble junction circuits employed, and the second to control the collection and reimbursement of coins for calls made by prepaid postas Another modification is the elimination of the automatic ringing device.



   Fig. 6 represents a double junction circuit
L1 and its selectors S1 and S2 which are used to establish connections to the station which has requested and to the station which has been requested. The link circuit comprises the usual conversation and control key K10, a release key Kll, a reminder lamp L9, a supervision lamp L10, and an occupancy lamp Lll. The banks of the selectors S1 and S2 are multiple with the banks of the similar selector S, on all levels, except the second which is left vacant.



   The TTS trunk transmission selector, shown in Fig. 7, is of the well known type with vertical and rotary motion, and is intended to provide the transmission efficiency required in trunk traffic. This selector is accessible to the long distance selectors associated with the "B" and "0" positions, and, in turn, it has access to intermediate selectors or long distance connectors, depending on the importance of the system. \ Line seizure control,

 <Desc / Clms Page number 8>

 response and disconnection is provided by. a fourth thread.



   Fig. 8 shows a connector for shared lines, combined for urban and: interurban service; this connector is of a known type and is accessible to interurban transmission selectors, such as the TTS selector, and to urban selectors (not shown).



   Fig. 9 shows a transfer junction circuit by which calls transferred from positions "B" and "A are completed, and this circuit is associated with the position apparatus of Fig. 5, Said circuit comprises a key d listening and monitoring K12, a release key K13, a line lamp L12, a supervisory lamp L13, and a busy lamp L14. The selector S3 which is reserved for the junction circuit L2, is identical to the selector S (fig. 4), and its banks are multiplied with the banks of selector S, on all levels except the second.



   Figure 10 shows an operator's telephone set OT2, a position device PA2, and a dial D2 for an "a" position. This equipment is the same as that provided for the "B" positions (fig. . 2), except that the automatic ringing device has been removed, and a call device transfer key K16 has been provided.



   Fig. 11 shows a trunk circuit L4 which is accessible to subscribers by a first selector and an auxiliary toll recording line. This circuit is associated with the device in position "A" of fig. 10, and includes a listening and monitoring key K18, a release key K19, a supervision lamp L16, an occupancy lamp L17 , and an L18 line lamp. The selector S4 associated with this junction circuit is the same as the selector S (fig. 4), and its banks are multiple with those of the selector S on all levels, except the third in which the auxiliary trunk lines are accessible.

 <Desc / Clms Page number 9>

 



   The rear call switch, shown in fig. 12, is associated with the position device "A" shown in fig. 10, and has access, by its benches, to the annotation trunk lines (such as the auxiliary line shown in fig.



   11), which are identified by conventional two-digit numbers. The switch is provided with an auxiliary switch to select the ringing current of the frequency required to transmit a signal to a particular auxiliary station on a subscriber line.



   The apparatus shown in the various figures of the drawing having been briefly described, a detailed description will now be given of the operations involved in calls made in a system to which the invention is applied.



   Assuming that an operator of a trunk switchboard has established a connection by the trunk line comprising wires 391-392 and terminating in the preselector LS, an inrush current, applied to the trunk line , at this switch board, energizes a relay 302 which is connected to the wires of the auxiliary line in series with a capacitor 350. The relay 302 remains mechanically locked in the working position, until it is unlocked by relay 303, and it closes a circuit for relay 305, which closes circuits in order to cause switch LS to search, in the known manner, for a free auxiliary line.

   When this auxiliary line is found, for example the one comprising the wires 340-344, the relay 304 acts to connect the wires of the trunk line to the wipers 334 and 339, and to open the circuit of the relay 305. The earth is now put. , by 313, 320, 387, 337, 342,362, on relay 353. Relay 303 is connected in parallel with relay 353, to contacts 346, but, due to the value of resistor 387, it does not energize at the moment. relay 353 energizes the

 <Desc / Clms Page number 10>

 lower bearing of relay 354, and turns on lamp L2, at contacts 369, to signal a call arriving on junction circuit L.

   Relay 354 closes, at contacts 372, a hold circuit for relay 304; at contacts 372, it closes a holding circuit for itself, and, at contacts 373, it turns on the occupancy lamp L3, this lamp remaining on as long as the connection is maintained.



   If the attendant is too busy, she can transfer the call to a different "B" position, momentarily actuating key K4, which allows relay 354 to release and open the hold circuit. relay 304. Relay 304 releases and causes switch LS to resume its seek operation. When a new free auxiliary line is found, the call is transmitted to a different "B" position and actuates the signaling relays of this position, as described for junction circuit L,
To answer a call arriving on junction circuit L, the attendant moves key K3 to the left, which has the effect of closing a circuit for relay 351, through 389, 215 and 234.

   Relay 351 closes a hold circuit for its bottom winding, through 360, relay 352, 392, 212, relay 203, and ground. Relays 203 and 352 energize in series with the lower winding of relay 351, and the latter opens the direct connection between the incoming and outgoing conductors of the junction circuit and loops them through the position equipment, circuits passing, respectively, through 340. 357. 223, 235, 237, 222 and 359, to the upper conversation wire of the junction circuit, and through 344, 365,220, 236, 240, 221 and 364, to the conver - lower station of the junction circuit. The relay 351 also disconnects, at 362, 1 relay 353 from the wire 342, and, at 361, it places the earth directly on this wire for

 <Desc / Clms Page number 11>

 energize relay 303.

   Relay 303 releases the relay
302 and opens the bridge to the auxiliary line at 314. The group lamp L1 is on at 315, to indicate the particular group of auxiliary lines from which the call is coming.



   Relay 353, released, opens in 368 the primitive excitation circuit of relay 354, and extinguishes lamp L2 in 369. Relay 352 prepares a retention circuit, at contacts 367, in order to keep the relays energized in the event that the key K3 is returned to the idle position before the call has been terminated. At 230 and 231, the relay 203 connects the operator's station to the conversation wires; it opens, in 234, the primitive excitation circuit of the relay 351, and, in 228, it puts the ground on the wire 28, in order to prepare the recorder so that it receives and records the digits. The position operator "B" can now speak with the calling operator and obtain the necessary information regarding the desired communication.



   Assuming the call is a transit call, to be transmitted to another network served by inter .. urban lines, such as the one comprising 391'- 392t conductors (fig. 3A) accessible in the fourth level of the bench of the interurban selector, and the recorder-sender is used to establish the communication, the operator of position "B" activates the key with digit 4 and then the key of starting ST, thus closing a circuit, including the von- tacts 20, for relay 11.

   At 17, relay 11 prepares a restraining circuit for itself in series with relay 12 and, at 15 and 16, it grounds on wires 29 and 30, respectively. When the first digit is recorded, earth is put on wire 322, thus energizing relay 13 which prepares, at 22, the circuit for starting the sender and prepares, at 23, a circuit for relay 12.



  When the attendant releases the switch-on command, the primitive excitation circuit of redo 11 is opened, thus

 <Desc / Clms Page number 12>

   that the short-circuit of the rail 12, allowing the latter to be excited in series with the relay 11, following which it closes the starting circuit of the sender in 18, prepares a retention circuit in 19, opens the primitive excitation circuit of relay 11 at 20, and closes a circuit for relay 14 at 21. Relay 14 energizes and transfers, at 25, the circuit for retaining wire 28 to contacts 19, making thus the recorder-sender independent of the earth from the operator position equipment.

   Relay 208, on energizing, short-circuits relay 207 at 253, it connects an additional earth to wire 30 at 254, and, at 255, it closes a circuit for relay 209. Relay 209 closes a circuit for the lamp L in 242, it prepares the automatic call circuit in 256, and closes the restraint circuit for relays 203, 352 and 351 in 257., Relays 205 and 206 are energized from earth on wire 30, and relay 205 opens the circuit passing through the operator position and connects the output end, through 238 and 239,248 and 250,253, 262 and 264, 213 'and 213, to the pulse contacts of the 'sender which are, at this moment, bypassed by the contacts of relay 502.

   Relay 206, while closing points in the above control circuit, grounds from K key contacts 258, through 249, 216, contacts 388, 366, relay 354, relay 355, to the battery. Relay 355 closes a latch circuit, through 376 and 371, to ground on 214, and connects the output talk leads to selector S at 374 and 378, connects ground to 381 at 375, and connects relay 356 to 382 to 377. A circuit is now closed for relay 402, which energizes relay 403, to prepare the selector to receive Its pulses.

   The relay b02 now opens the short circuit of the pulse contacts of the sender switch I, and four pulses are transmitted by the loop, after lons

 <Desc / Clms Page number 13>

 which the relay 503 energizes and again puts the pulse contacts in short circuit. The relay 402 acts in the usual manner under the effect of the pulses, and transmits four pulses, by 420 and 422, to the relay 404 and to the ascension electro 406 in series. Relay 404 remains actuated throughout the series of pulses, and electro 406 lifts the step-by-step wipers to the fourth level. The off-normal contacts 424 and 427 close, during the first vertical movement, and these latter contacts close a circuit for the relay 405 which is energized and locked by 430, 429 and 416.

   Shortly after the last pulse of the series, the relay 404 returns to rest and closes a circuit to initiate the switch search operation, by the mutual action of the relay 405 and the rotation electro 407.



  When a free auxiliary line is encountered, for example the auxiliary line including wires 384-386, the test wiper will not find earth, and the relay 401, no longer short-circuited, will act in series. with relay 405 which, however, will not operate at this time. Relay 401 disconnects line relay 402 from wires 380 and 383, at 411 and 418, respectively; it connects these wires by 412 and 417, to the upper and lower wipers of the selector; connects the test wiper, at 415, to grounded thread 381, and opens a point, at 416, in the release circuit.

   Assuming that the chosen auxiliary line is the one ending with the trunk line comprising the wires 391'-392 'of FIG. 3A, the earth on the test wiper is connected by 384, 331 'and 324', to activate the relay 303 'which opens the bridge including the relay 302' connected to the auxiliary line, so as to prevent the operation of the associated preselector, when inrush current is sent on the trunk line.



   The recorder is arranged so that the earth is disconnected from wire 322, when the digit (s) in-

 <Desc / Clms Page number 14>

 registers have been transmitted. Consequently, the relay 13 is released, it opens at 22 the starting circuit of the sender, and opens at 23 the retaining circuit of the relays 11 and 12.

   Relay 11 returns to rest and disconnects the earth of wires 29 and 30, Relay 12 returns to rest and opens the circuit of relay 14, which also returns to rest, After a short period of time, relay 208 is released, as the earth is removed from wire 29; it opens the short-circuit of the relay 207, and opens a point in the circuit of the relays 205 and 206. The relay 207 is thus momentarily connected to the conversation wires of the auxiliary line, but it is not energized as a result of the changes. - high resistances in series with relay 301.

   Relay 206 is released before relays 205 and 209, and while the latter are kept energized, a circuit is closed from the battery, through 211, 256, 247,238, 222, 359, 374, 380, 412, the wiper upper of selector S, 386, the lower winding of relay 301 ', fig. 3A, to earth. Relay 301 'energizes momentarily, and applies inrush current to the trunk line, at 309' and 312 'in order to actuate the line signal placed at the remote trunk switch board, and attract the line signal. attention from an operator at this point. The operator in position "B" can now speak, either with the calling operator, or with the called operator, by pressing one or the other of the keys K1, K2.

   The movement of the key K1 to the left closes a circuit, at 241, for the relay 204, and the latter disconnects the calling trunk line from the operator station at 235 and 236. The movement of the key K2 to the left, closes, at 243. a circuit for relay 205, and this relay is energized to disconnect, at 237 and 240, the trunk line called from the droper station. ratrioe, After making sure that the operators call

 <Desc / Clms Page number 15>

   and called are properly connected, the "B" position operator will withdraw from the connection by returning key K3 to the normal position, thus releasing relays 351, 352 and 203.

   The relays 354 and 355 will however remain energized and will maintain the connection of the calling trunk line, through the trunk circuit and the selector, with the called trunk line, which, incidentally, will be in normal condition, the relay 301 being ra- led to the rest position. Relay 351, on returning to the home position, will disconnect ground from wire 342, thereby allowing relay 303 of the calling trunk line to return to the normal position. The calling and called operators can now complete the connection leading to subscribers in their respective urban networks.



   The "B" position operator can listen at any time on the connection, without disturbing the communication in any way; for this purpose, the key K3 is moved to the right, or to the monitoring position, after which a circuit is closed; by 395,219 and 233, for relay 202.



  At 225 and 226, relay 202 connects the receiver to the secondary winding of the induction coil IC, the primary of which is normally connected to wires 217 and 218 in series with a capacitor, and, since the key K3 is actuated, the wires are connected to the upper and lower conversation wires of the junction circuit, by 393 and 394, respectively. However, the attendant, in position "B", cannot speak on this connection, since the transmitter of her set is not connected.



   The monitoring key can also be used to answer calls, when the transmitter is associated with one of the trunk circuits; at this time, relays 203, 205, 206, 208 and 209 energized, as well as relays 351 and 352 of the junction circuit. The answer key

 <Desc / Clms Page number 16>

 K3 of the junction circuit is returned to the normal position, and the relays are kept energized by contacts 257.



  If we now activate the monitoring key of another junction circuit, the conversation wires of the latter will be connected to the operator's set. The relays 351 and 352 of the second junction circuit will not be energized, and the line lamp will continue to glow. However, the "B" position operator can talk to the calling operator, since her set is connected to the position machine by relay 203, which is kept actuated by the auxiliary circuit of the first control circuit. junction. When the sender ceases to operate, the auxiliary circuit is opened in the usual manner, thus connecting the first trunk line to the called line.

   The attendant set will be disconnected by releasing relay 203, although, of course, it will still be connected, for monitoring, to the second trunk line. The attendant will then activate the listening key for the second junction circuit, and complete the connection as in the previous case.



   In the event that the operator in position "B" wishes to transmit a signal to the operators standing at one or other of the remote trunk switchboards participating in this communication, she brings the required call key to the position occupied by the key K3. Moving the key K1 to the right, energizes the relay 204, which disconnects the incoming line from the junction circuit of the operator's station, and connects it to the contacts of the key.

   Relay 301 is now energized by the following circuit: battery, 211, 263, 261, 223,357, 340,334, 316 and the top winding of relay 301, to ground, and applies an inrush current, at 309 and 312, on the .interurban line * The displacement of the key K2 towards the. right, energizes relay 205, which disconnects the outgoing line from the operator's station junction circuit, and connects it to the key contacts, after which a battery circuit is closed, by 211,244, 238,222, 359,374, 380, 412, the upper trot-turn of selector S.386, 1; upper winding of relay 301 ", to earth, end of forcing relay 301 'to apply, in 309' and 312 ', a inrush current on the called trunk line.

 <Desc / Clms Page number 17>

 



   When the call is ended, either of the attendants can ring in the usual way, thus activating the relay.
302 of the calling auxiliary line, which will apply earth to 313, 320, 387, 337, 342 and 362, to actuate the relay
353, which, in turn, will turn on the L2 lamp, in order to indicate that the operator must intervene in this communication,
The "B" position operator then intervenes in the connection, and, if she has no other service to do, she will return key K3 to the normal position and momentarily activate key K4.

   The operation of the key k4 opens the relay circuit
354 which returns to idle and releases relay 355, which disconnects the earth from wire 381, thus allowing the relay to be released.
401 which returns the selector S to the normal position in the usual manner.



   If no free auxiliary line had been available in the fourth level of selector S, the rubbers would have come to the eleventh position in which the eleventh position springs are actuated. The earth on the periodic occupancy switch is connected, at 410, to the conductor
382, to cause relay 356 to turn on lamp L14, intermittently, and a signal is transmitted over the top talk wire of the auxiliary line, through 409, 440, and 412, to inform the attendant that no connection is made. with the called long distance line cannot be established at this time.



   The establishment. , by the operator of position "B", of an incoming call is effected in the same way as the transmission of a transit call, except that a series of trunk switches is used to establish a call. connection with a subscriber line. We will now give a description of a call reaching the abbnne at the auxiliary station T (fig. 8), whose number is 4568, assuming that the connection is established using dial D.

   Since the auxiliary lines connected to the group of interurban transmission selectors comprising the TTS selector (fig. 7 (, are accessible in the third level of the selector S banks (fig 4), it will be necessary for the attendant to train on her

 <Desc / Clms Page number 18>

 dial number 34568 to reach the called subscriber, after having answered the incoming call, as described previously, the operator in position "B" will activate the key K20, thus connecting dial D in place of the recorder sending, and it will operate the dial to send the number 3. The off-normal contacts 270 and 271 close when the dial is rotated from the normal position, and apply a ground to energize the relays 205, 206, and 208.

   A control circuit, comprising the pulse contacts 272 of the dial and the contacts
263 and 265 of key K20. is connected, by the position equipment and the junction circuit, to the selector S, as in the communication previously described. The selector,
This is the. usual manner and chooses a free auxiliary line, for example the one comprising the wires 435-438, which is accessible in the third level.

   As the selector moves, the control circuit is further connected to the upper and lower trotters of the trunk selector and to wires 435 and 438, with wire 435 being connected through the lower left winding of the repeat coil.
RC, 770 and 723, to ground, and wire 438 being connected. by the upper left winding of the RC repeat coil, 769, 716, relay 707, and 746, to the battery,
When the calling device returns to the normal position, contacts 270 and 271 open, after which relay 208 returns to idle and opens the short circuit of relay 207.

   Relay 207, momentarily connected to the control wires, is energized in series with relay 707 of the TTS selector, to close a new circuit, at 251, for relays 205 and 206, and close a circuit, at 252, for the relay 209, The separation of the incoming and outgoing wires of the junction circuit is thus maintained, and the battery and the earth on the selector will not apply any to the trunk line, so xxxxx false signaling cannot be result. Relay 209 maintains the circuit. restraint for relays 203, 351 and 352. and also

 <Desc / Clms Page number 19>

 the circuit for the lamp L.



   It should be mentioned that operations similar to those indicated above take place when the sending link-4 registrar is used and only part of the called number is transmitted. This allows the attendant to complete the connection from this point by re-operating the sending recorder or to release and re-establish the connection.



   Relay 707 acts in series with relay 207, and closes a circuit for relay 708 which energizes and ¯ prepares, at 748, the usual pulse circuit. The operator can now form the number 4 on her dial and relay 707 acts accordingly. Each time relay 707 is de-energized, a circuit is closed from the earth, by 744, 748, 751, the ascension electro 713, to the battery, and in parallel with this one, by the relay 710, to the battery, Relay 710 remains energized during the whole series of pulses and short-circuits the upper left winding of the RC repeater coil, at 757, in order to improve the transmission of the pulses, while the 'éleotro raises the rubbers of the switch to the fourth level.

   During the first vertical movement of the selector, the contacts 765 close a circuit for the relay 705 and the contauts 781 close the circuit of the relay 711, from the ground on the test wire 437, by 742, 752, 759, the relay 711, 781 and 746, to the battery. When releasing relay 710, shortly after the last pulse in the series, relay 711 and rotation electro 712 act to produce the selector search movement in the usual manner.

   When a free auxiliary line is found, for example the auxiliary line comprising the wires 774-777 there will be no earth on the test contact, and the relay 709, being no longer short-circuited, will fail. will excite

 <Desc / Clms Page number 20>

 in series with relay 711, which is not energized at this time. The relay 709 closes points in the control circuit of the switch, forward in 749 and 755, it closes a point, in 750, in the bell control circuit, it disconnects, in 751, the ascension electrode, and it connects, at 753, the test wiper to the incoming test wire of the switch, Relay 709 also closes a circuit from earth, through contacts 745, 782, 763, 717, relay 701, to the drums.

   At the same time as this circuit is closed, a circuit is closed for the lower winding of relay 701 and of the pulse relay 805 of conneoteur C in series. This circuit can be traced as follows: From the battery, by the upper winding of the relay 803 827, 817, 774, the upper wiper of the TTS selector, 743, 749, 730 the upper right winding of the repeater RC, 719, relay 701, the lower right winding of the repeater coil 734. 755, the lower switch of the selector, 777, 825, 829, the relay 803, to earth. Relay 803 energizes by this circuit, but the direction of current flow is such that the two windings of relay 701 oppose each other and, therefore, this relay does not function. not at this time.

   The operation of relay 803 energizes relay 804, which, while making other changes of circuits, actuates relay 807. When the connector is taken, IL% earth is transmitted, through 732,750, the control wiper, 775 , 847, relay 806, to the battery.

   Relay 806 energizes and prepares a latch circuit for itself in series with the lower winding of relay 805 which, however, is at this time shorted by contacts 847.
The attendant now forms the number 5 on her dial, and relay 707 acts as in the previous case, while relay 710 operates at. again to bypass the upper left winding of the. RC repeater coil, Whenever relay 707 de-energizes, the air ..;

     looped through relays 803 and \ 701 is open right side up

 <Desc / Clms Page number 21>

 743 contasts, and relay 803 acts accordingly * Air. fired from the top winding of relay 701, is opened simultaneously at contacts 745, so that relay 701 is not actuated during pulse transmission. When the relay 803 acts under the action of the pulses, a corresponding series of pulses is transmitted to the lift electro 812, which acts to lift the shaft and the trotters up to the fifth level, The relay 810 is connected parallel to the ascension electronics and remains activated during the whole series of pulses.

   The primitive excitation circuit of relay 807 is opened in 890 / during the first vertical displacement of the switch, but the relay remains energized by 856 and 875, during the transmission of this series of pulses, after which it is released and connects the electro rotation 81. the place of the ascending electro 812. The opening of the contacts 847 allows the relay 805 to act, and, among other circuit changes it closes a latch circuit for itself at 845, and separates into 843 the trunk line wires and the local test lead.



   The operator now forms the number 6 on her dial, and relays 707 and 803 act as before.



  Relay 810 energizes again during the series of pulses, and at 872, prepares the busy test circuit. The rotation electro turns the wipers and brings them into engagement with the contacts of the called line. In the event that the line is busy at this time, the test float meets earth on the test contact, which energizes relay 809. Relay 809 prepares a hold circuit for itself; in 867 he prepares a new holding circuit for the relay 805, xxxxxxxxxxxx in 869; opens the pulse circuit at 870; and it closes a circuit which can be traced from the busy signal switch, through 841, 899,818, 835, 877, relay 802, to the battery.

   Relay 802 acts in this circuit and reverses the connection of line relay 803 to the auxiliary line, after which the,,. , .................,

 <Desc / Clms Page number 22>

 relay 701 energizes and closes a holding circuit for its upper winding, at 718. The control loop connected to the connector is disconnected from the lower winding of relay 701 and is connected, by the windings and of relay 702 , to the battery to earth. Relay 802 also closes a circuit, through 826, 883, and 844, for. relay 801. Relay 801 energizes and stays earthed at 822; by wire 776; he disconnects, at 817 and 825, the line wires of relay 803, and ends them with the auxiliary conversation wires of the connector at 819 and 824.

   Relay 801 also connects additional ground at 821 to local test lead 779 and at 823 opens a point in the release circuit to prevent release of the connector at this time. Opening of contacts 817 disconnects relay 802 from the circuit comprising the busy signal switch, and the latter is connected, through 819, 774, 743, 749, 730, to the upper right winding of the coil. repeater, 720, relay 702, to battery, relay 702 is energized intermittently by the ground of the busy signal, and, on each energization, it closes a circuit for the relay 703.

   Another circuit, closed when the relay 701 is energized, extends from the battery, via the relay 356, 377, 382, 413, the selector control wiper S, 436, 724, the relay 706, 729, relay 707, to earth. Relays 356 and 706 energize in this circuit and relay 707 is kept energized to maintain the connection. Relay 356 closes a circuit for monitoring lamp L4, while relay 706 opens the circuit of relay 705 at 738; prepare a hold circuit for itself at 739 and 741, (circuit which is closed when releasing relay 705); and shunts, at 740, its own lower winding, so that it remains actuated until the hold circuit is closed by relay 705.

   The supervisory circuit now only includes relay 356 and the lower coil of relay 707.

 <Desc / Clms Page number 23>

 



   The intermittent operation of relay 703 serves to open the supervisory circuit at 729, and, at 728, to connect the battery, through resistor 772, to the lower winding of relay 707, in order to prevent releasing of the latter.



  Relay 356 accordingly energizes and de-energizes intermittently, causing lamp L4 to flash light, to indicate to the operator that the subscriber line is busy at this time. The current interrupted in the right winding of the RC repeater coil, will induce a signal in the left windings, which signal will be audible to the calling operator. The interrupt speed may be different from that used at the selectors, thus giving an indication of the phase of the call where. the occupation condition is met.



   Disconnecting relay 707 from the control loop, while relay 701 is operating, will prevent relay 207 from acting when the calling device returns to the normal position, and relays 205, 206, 208 and 209 will therefore return. at rest and restore the loop to the operator position. The attendant will then release this connection by returning key K3 of the junction circuit to the normal position and pressing key K4.



   However, if the called line is free, the connector test wiper will encounter the. battery by the cut-off relay of the line switch, and, when the relay µ¯la returns to rest, shortly after the last pulse of the series, the test wiper will be connected, through 871, to the upper winding of the relay 811, and from there to earth, through 866, 861, and 837, Relay 811 is then locked at 886; cexxxxxx relay closes points in the conversation circuit at 878 and 898; it closes a point in the back call circuit, at 879; it closes a hold circuit for relay 806 at 880; connect earth directly to the test wiper at 881; opens a point in the relay 809 circuit at 882;

        and transfers the pulse circuit of the electro 813

 <Desc / Clms Page number 24>

 to electro 815 in 887
The operator will now form the last number 8 on her dial and the glazes 707 and 803 will act as before. A corresponding series of pulses will be transmitted to the electro 815, which will accordingly advance the sliders 891 and 892. of the auxiliary switch. At the end of the series of pulses, relay 810 will return to idle, and, since off-normal contacts 889 closed when the trotters on the / auxiliary switch have moved out of the normal position, a circuit will be closed, from earth by xxx 874 and 889, relay 808, to the. drums.

   When the auxiliary switch slider 891 passes the first half of its bank, a circuit is closed for the relay 807, which energizes and reverses the ringing circuit with respect to the sliders. Relay 808 closes a circuit for relay 801, par 8 44, 862, 885 and
836, to the ground. Relay 801 energizes, switches the connector to the talk position, and drops relays 803 and 804. Relay 811 is now kept energized by 885, 862 and 822, to ground on the 776 test lead. Auxiliary line talk wires are connected directly to the switch wipers, since bell interrupt relay 806 is energized by control wire 775.



   Disconnecting relay 803 from the auxiliary line opens the loop circuit by which the lower winding of relay 701 has been energized to oppose the upper winding of this relay. Relay 701 now energizes xxxxxx by its upper winding alone, and closes a hold circuit for said winding to earth at 765.

   Auxiliary wires 435 and 438 are disconnected from shine 707, and wire 435 is connected, through 722, to relata 704. Relay 707 is kept energized in series with relays 706 and 356, through wire 436, and these relays. act and produce the same results as previously described

 <Desc / Clms Page number 25>

 
However, the L4 lamp now illuminates continuously to indicate to the operator that the requested line has been taken.

   During the time interval between the release of relays 206 and 208 and that of relays 205 and 209, a battery circuit will be closed, by 211, 256, 247, 238, 222, 359 374, 380, 412 , xx the upper selector switch S, 435, the lower left winding of the repeater coil RC, 770, 722, the relay 704, to earth. Relay 704 energizes and disconnects the bell control circuit ground at 732, thus releasing bell interrupt relay 806 from connector C, which closes the bell circuit of the switch and generator. by the slider 892, 863, 857, 848, 878, the upper connector slider, the subscriber line, the lower connector slider, the contacts 898, 853, 854, the relay 806, to the battery.

   The subscriber is warned intermittently by ringing with the aid of a current which, in this case, is of a frequency to which only the bell of the auxiliary station responds. When the called subscriber answers, a direct current bypass is closed at his station, and relay 806 energizes to disconnect the ringing current from the line, connect the line wipers to the conversation wires of the switch, and hold on. new to the control circuit. Relay 702 is now actuated by the subscriber loop and, at 725, energizes relay 703 which connects an additional earth to the ringing control circuit at 727; and closes a local hold circuit for relay 707 eh 728; while in 729 the circuit for relay 356 is open.

   Releasing this relay has the effect of switching off the L4 lamp, in order to indicate that the called line has answered. The "B" operator now withdraws from the connection by returning the key K3 to the normal position, but the connection will still be maintained, since the relay 354 is maintained by the contacts of the key K4. , and that relay 355 is maintained by the normally closed oontacts of key K3.

 <Desc / Clms Page number 26>

 



   At the end of the conversation, the called subscriber hangs up his receiver, thus opening the loop circuit by which relay 702 was energized, and the latter returns to idle. Relay 703 will also return to idle and connect to. again the lower winding of the shine 707 to the supervision circuit, thus again actuating the relay 356 of the junction circuit. Relay 356 will again close the circuit of lamp L4 which will light up to ensure a disconnection check in position "B" The attendant can call back the called subscriber by ringing, by moving the key K2 temporarily to the right, after which the battery is connected at 244, by resistor 211, to actuate relay 704, in order to obtain the results previously described.



   When the. supervision lamp L4 comes on, the operator in position "B" after asking if the conversation is finished, and not having obtained an answer, will send a signal to the remote toll operator by applying a current of ringing at the long distance line. This operation is carried out by moving the key K1 to the right, which has the effect of closing a circuit at 264, for the relay 204, which then disconnects the incoming conversation wires from the junction circuit, from the station. the operator, and connects these wires, through 261 and 262 to the contacts of the call key K1, The battery, through resistor 211 and through 263, excites relay 311, which, at 309 and 312, applies a current ringing on the long distance line.

   The ringing current will activate the signal placed at the remote long distance switchboard, in order to inform the operator that the conversation is over and that the connection must be released. The operator of position "B" can wait on the line and speak with the remote operator, if she wishes it,
The position operator B will now release the series of switches by returning key K3 to the normal position and momentarily actuating key K4, thus releasing

 <Desc / Clms Page number 27>

 relays 354 and 355, last disconnecting the outgoing wires from the trunk selector junction circuit, selector S, transmission selector TTS and connector C are kept actuated by earth on wire 381, as previously described, and when this earth is withdrawn,

   the switches return to the normal position. Thus, in the selector S, the relay 401 is released and energizes the release electro 408 which returns the wipers to the normal position in the usual manner.



   Removing the soil from wires 436 to 437 allows
707 will release relays 701, 706, / 708, and 709 of the transmission selector, and the release solenoid 714 will then return this switch to the normal position.



   Relays 801,805 and 811 are released when ground is removed from wire 776, while relay 806 is released as ground is removed from wire 775. Relays 807 and 808 depend on the off-normal position of the auxiliary switch, and are released when this switch has been returned to the normal position by energizing the electro 816, by 823, 833, 839 and 865. The switch c is reset to the normal position by the function -nning of the electro 814 in a branch of this circuit, by 831 and 834.



   In the event that the interurban transmission selector (fig. 7) does not find a free auxiliary line, the trotters are brought, by a rotational movement, into the eleventh position to determine the operation of the springs 763, 764 and 768. If the device giving a cut signal is connected to give a busy signal, when the wipers reach the eleventh position, the loop for the lower winding of the relay 701 will be opened, which will allow this relay to s 'activate and switch the selector to the talk position.

   The communication relay 709 will also function as for a successful call and a busy signal will be transmitted, via 768, to the

 <Desc / Clms Page number 28>

 resistor 773, 749, 730, the upper right winding of the RC repeater coil, 720, and relay 702, to the battery. A signal will be induced in the left winding of the repeater coil and will serve to alert the operator that no free auxiliary line is available at this time.

   In the case / the occupancy signal switch is connected to give an occupancy signal by flashing light. when relay 701 acts, the moment the switch comes to the eleventh position, the interrupted earth will be transmitted through the circuit previously drawn, in order to determine the intermittent operation of relay 702 and hence. relay 703, which will Intermittently open the supervision circuit in 729, Relay 356 will thus force the lamp L4 to light up intermittently, and the current interrupts in the right winding of the repeater coil will induce a signal in the left windings, which will be audible to the calling operator.



   It will be noted that connector c is accessible to local and interurban selectors, and, for urban connections, conductor 779 will operate and wires 775 and 776 will have no other function than to make the switch in the banks occupied. interur .. bath transmission selectors. In urban connections, relay 805 will therefore not be able to be energized, and, consequently, relay 801 will not be able to operate. Relay 806 is not energized when the switch is seized, and ringing current will automatically be applied to the called line as soon as the auxiliary switch is turned.

   Further, in city connections, relay 803 will provide talk current to the calling subscriber, and relay 802 will provide talk current to the called subscriber and reverse, equal. ment the direction of current flow through the. calling line, in order to carry out operations / counting and supervision.



   IF the key operator in position "B" is not able to complete a call, the latter may be transferred to a position C, and completed by the operator from this position.

 <Desc / Clms Page number 29>

 



   B position. The position attendant / will answer an incoming call via the auxiliary line shown in fig. 3, as previously described, but instead of forming the number of a trunk line or a subscriber line, ending in position C, for example an auxiliary line it will store the number of an auxiliary line / accessible on the second level in the benches of the selector S, (fig. 4), and it will be assumed that the auxiliary line comprising the wires 431, 434 leading to the connection circuit L2 (fig. 9), is taken.

   The earth on the test lead 433 is now connected to 924 and 926 to light the lamp L12, in order to signal a call on this junction circuit, The xxxxxxxxxxxx supervision wire 432 is connected, by 9393 and 930 to the earth , so that relay 356 energizes and lights lamp L4 to indicate that the connection has been made in position C. The attendant from this position now moves key K12 to the left, which closes a circuit of the earth, by 534, fig. 5, ble, 907, relay 902, relay 903, to the battery.

   Relay 902 closes a hold circuit for itself and for relay 903 in series with relay 503 ', through 919, 908 and 512, and separates the incoming talk wires of the junction circuit from the talk wires of start and loops them by the position device, as can be seen easily, the operator's set being connected to this loop at 530 and 531, so that the two operators can talk to each other, Relay 903 opens the circuit of the lamp L12 in 924, it applies a ground to the wire 433 in 925, and opens the supervision circuit to the contacts 939, so that the lamps L12 and /. L4 are off,
Operator C can now connect the connection via selector S3 to an interurban line leading to another urban network, or to a subscriber line,

   through a series of trunk switches, such as TTS and C. Operator C registers the requested number on the KS keypad, and lowers the start key, after which earth is reapplied on wires 29 and 30

 <Desc / Clms Page number 30>

 to energize relays 505, 506, 508 and 509. The starting wires of the junction circuit are transferred to the sender's control circuit by relay 505, and relay 506 closes a circuit from earth, through 570, 558,549 , 673, 516, 906, relay 905, to the battery. Relay 905 is connected by 932, 911 and 909, to ground on wire 514 while the K12 key is actuated, and, when this key xxxx is returned to the normal position, the lockout circuit is transferred. to earth in 910.

   Relay 906 connects the talk leads of the junction circuit to wires 934 and 937, and earth is connected to wire 935 at 942, while wire 936 is connected to @ relay 904 'through' 933. Lamp L14 comes on to mark this auxiliary line busy for the duration of the call.



   The sender, completing the transmission of the stored digits, removes the earth from wires 29 and 30, after which relays 508 and 509 return to idle.



   Relay 507 is now momentarily connected to the loop leading to the switches, but only energizes when a connection has been partially established, and in this case closes new restraining circuits for relays 505, 506. and 509. In a connection not established as described, relay 507 / does not energize, therefore the calling device is disconnected from the loop and the calling and called lines are connected to the position apparatus.

   Operator c can now withdraw from the connection and put the ringing command under the control of operator in position B, or else she can initiate a ringing by moving the key K6 to the right. In the latter case, the operation of this firm key

 <Desc / Clms Page number 31>

 a circuit for relay 505 which connects the battery through 511 '544, 583, 577, 538, 522' 917, 929, and 934, in order to actuate the bell relay of the junction circuit or the start relay of transmission selector ringing.



   Operator 0 withdraws from the connection by returning key K12 to the normal position, whereupon relay 902 is released, and relay 903 is kept energized by its lower winding. The talk leads of the junction circuit are connected to the junction circuits L of position B, and in the case where the answer key of this junction circuit is still actuated, the circuit includes the loop passing through position B.



  The position operator's set B is connected to this loop, so that this operator can talk to either the calling subscriber or the called subscriber. When desired, the operator in position B can also control the bell by moving the key K2 (fig, 2) to the right, thus applying the battery, by resistance 211, to the upper conversation wire of the junction circuit.



   In the case of calls by the series of long distance switches, supervision is ensured, at position 0, by a lamp L13 which lights up when the earth is again put on the supervision wire 936. Operator 0 can then release the connection by returning the key K12 to the normal position and momentarily actuating the key K13 All the relays of the junction circuit L2 will be brought back to rest, and the earth will be put, through 930 and 939, on wire 432 to switch on the lamp L4 in position "B", The operator in position "B" will then transfer control of disconnection to the calling operator, and will release the rest of the connection in the usual way.

 <Desc / Clms Page number 32>

 



   We will now describe the operation of the annotation position A device shown in figs. 10 to 12. The operator's station and the position device (fig.10) are in principle the same as those shown in fig. 2, with the addition of a K16 callback key and said device is intended to work with a recorder-sender as shown in fig 1. Assuming that the T2 subscriber wishes to call a subscriber from another urban network, he will train on its dial the conventional number reserved for the annotator, after which the pre-reader LS1 and the selector S5 will act to choose the auxiliary line connected to the junction circuit L4.

   Relay 1104 is energized by the subscriber loop; it energizes the relay 1102 in 1123, and lights the line lamp L18 in 1124. The relay 1102 connects a call back signal in 1115 and connects the earth to the test lead, through 1151, 1161 and 1154, in order to keep actuated urban switches. Noting that the lamp has come on, the annotator will answer the call by moving the key K18 to the left, after which the hold circuit is transferred from 1154, through 1153 and 1014, to ground in 1059. of the release key K17, A circuit is also closed from earth, through 1034, 1015 and 1160, for relay 1106, which is connected, through its lower winding in series with relay 1107, through 1130, 1156, 1012, and relay 1003, to earth.

   Relays 1103 and 1107 also energize, relay 1107 preparing a hold circuit through 1136 and 1060 and also preparing a circuit for relay 1109 at 1135. The incoming and outgoing conversation wires of the circuit junction boxes are open and looped through the positional equipment, and the operator's station is connected to the loop, to the positional equipment at 1030 and 1031, so that the annotator can speak with the subscriber calling to find out what he wants.
 EMI32.1
 



  Intergrbaing calls can be COMPLETED directly by the hostess if possible, either

 <Desc / Clms Page number 33>

 indirectly by operator C. In each case, the annotator will establish the usual form on which are recorded the various data necessary to bill the call. In the case of a call on hold, this form will be passed to operator C who will complete the call as explained below. If the annotator must complete the call directly, it forms the code number, for example 3, necessary to choose a particular group of auxiliary lines connected to the requested office.

   After lowering the key bearing the number 3 and forming part of the KS keypad, the attendant will activate the start-up key to initiate operation of the control device (fig. 1), as described previously. As in the previous connections, earth on wires 29 and 30 will actuate relays 1055,1006 and 1008, and this latter relay will close a circuit for relay 1009. Relay 1005 disconnects the incoming wires from the position loop. junction circuit and connects them to the control loop comprising the switch-sender pulse contacts.



  The relay 1009 closes the usual restraint circuit for the relays 1003, 1106 and 1107, in 1057; it turns on the dial lamp L15 in 1065. The relay 1006, while connecting the control loop in the usual way, closes in 1049 a circuit for the relay 1109 which is connected by 1140 and 1161 and turns on the occupancy lamp. L17. The relay 1109 connects the conversation wires of the link circuit to the selector S4, in order to place the latter under the control of the register.



  -sender, and it closes a retention circuit for the relay 1102, so that the latter remains actuated even if the calling subscriber hangs up his receiver and releases the relay 1104.



  The selector S4 acts under the action of the pulses transmitted by the sender, and it chooses an auxiliary line which will be assumed to be the one comprising the wires 384-386 which are connected to the interunbain line shown in FIG. 3A. Wandering over test leads 384 activates a switch relay

 <Desc / Clms Page number 34>

 305; of the trunk line is called, and the conversation wires of the auxiliary line are connected to the conversation wires of the trunk line. Upon completion of the orientation, the circuits of relays 1005, 1006 and 1008 will be opened by the sender, and these relays will return to idle. Relay 1008 opens the short circuit of relay 1007 which, however, does not act in established communication.



  The annotator will now send a signal to the remote attendant by moving the K15 key to the right, thus energizing the relay, is 1005 to connect the outgoing wires from the trunk circuit to the bell key. The relay 301 'is energized by the battery, by 1011, 1044, 1038, 1022, 1128, 1138, 1144, the upper friction of the selector S4, 586, the upper winding of the relay 301', to earth; it connects ringing current to the trunk line to transmit a signal to the remote operator. The two operators can now talk to each other, the annotator providing the information needed to complete the call.



   The annotator can withdraw from the connection by returning the key K18 to the normal position, and the calling subscriber can now speak with the called subscriber.



   At the end of the conversation, the calling subscriber, by hanging up his receiver, releases the relay 1104 which closes a circuit, through 1125 and 1120. for the lamp L18, which lights up to indicate to the annotator the end of the conversation.



  When the called subscriber hangs up his receiver, the attendant at the remote office will receive the usual supervisory signal and apply ringing current to the auxiliary line, which will activate relay 1105 of junction circuit 14.



  Relay 1105 is mechanically latched and, at 1126, closes a circuit for supervisory lamp L16 to give the annotator the disconnect control signal.



   The connection is released by the momentary operation of the

 <Desc / Clms Page number 35>

 
 EMI35.1
 key 77.9 which allows relay 1109 to return to the normal position, disconnects selector S4 in 1138, 1139, 1141 and 1143, and opens the circuit of relay 1102 in 1142. may sometimes wish to retrieve the subscriber who requested the communication, which it can do, in the present system, without the danger of calling another subscriber on a subscriber line and through an annotator connection. Without releasing the connection, the annotator will form on the recorder-sender a conventional number, the first two digits of which, for example 23, will identify the auxiliary line of anM notation in use, and whose last digit, for example 4 , will identify the subscriber who requested the call.

   Consequently, the annotator will form the digits 2, 3 and 4 on the recorder and, after having actuated the key 1CL6 of its position device, it will lower the key for starting the calling device as usual. The operation of the key K16 disconnects the wire 30 which has no use in the present connection, it connects the wire 29 to the lamp '1; 15, so that this lamp shines while the sender is in action, and it disconnects the pulse wires 213! and 213 of the position device, and connects them, via wires 1073 and 1074, to the two windings of relay 1201 of the RC connector (fig. 12). Relay 1201 then energizes relay 1202, which prepares various local hold circuits in 1224 and 1225, prepares the pulse circuit of 1226, and opens a point in the release electro circuit, in 1227.

   The sender now transmits the digits 2 3 and 4, and relay 1201 acts accordingly. Under the effect of the first series of pulses, relay 1201 transmits pulses through a circuit which initially comprises 1225, 1226, 1218, relay 1205, the ascension electro 1209 the battery, so that this electro 1209 lifts the wipers step by step to the second level, and the r6la's 1 203 remains actuated during the whole series of pulses.

 <Desc / Clms Page number 36>

 



  A pulse circuit is closed at 1217 and 1228, and the primitive circuit is opened at 1218 when the off-normal springs act on the first movement in the vertical direction. At the end of the first series of pulses, relay 1203 returns to the normal position and transfers the pulse circuit, through 1229, il? 41, 1251, to the rotation electro 1210. Relay 1201 acts in the same way under the effect of the second series of pulses, and transmits corresponding pulses, through the pulse circuit, to actuate the electro 1210 which turns the wipers step by step up to the line contacts annotation auxiliary called.

   Relay 1206, which is connected in parallel D. the electric, remains actuated during the whole series of pulses and, when! is de-energized, it closes a circuit for relay 1207, this circuit being able to be traced as follows: from the battery, by the switch relay 1101 from the junction circuit,
1149, the RC connector test wiper, 1244, the relay
1207 1239 and 1224, to earth The relay 1207 locks in 1257 it closes points in the bell circuit in
1249 and 1252, directly connects the earth to the test wiper through 1233 and 1248, and transfers the pulse circuit from the electro 1210 to the electro batter 1214 of the auxiliary ringing current selection switch.

   Relay
1101 of the junction circuit energizes by the above circuit and disconnects the auxiliary incoming wires from the junction circuit and connects them to the auxiliary wires 1148 and 1150 connected to the ringing rubbers of the RC storyteller.



   Relay 1101 also applies a restraining ground on the Iteration auxiliary wire, to contacts 1112, to maintain the connection from calling line 1, during the signaling operation.



  The sender now sends the last digit 4 and the relay 1201 acts accordingly and transmits a corresponding series of pulses to the electro 12414. The relay

 <Desc / Clms Page number 37>

 1206 acts again during the series of pulses, and the electro advances the wipers of the auxiliary switch to the fourth series of bank contacts. Shortly after the last pulse in the series, relay 1206 returns to idle, and a circuit is closed, through auxiliary switch wiper 1220 and contacts 1246, for relay 1206.

   Relay 1205 then opens the pulse circuit at 1241, closes points in the ringing circuit at 1240 and 1242, and closes a point in the circuit. release at 1243. A ringing current is now applied intermittently to the line by a circuit extending from the earth or the earthed generator, to the switch, through the wiper 1221, la'3'7, 1242, 1252 1256. the connector wiper, 1148, 1111, the selector S5, the line switch LS1. station T2, line switch LS1.

   the SS selector, 1113, 1150, the connector wiper, 1255,
1249, 1240, 1255. the bell interrupt relay 1204, on the battery, The bell sounds at the station corresponding to the signaling current sent, that is to say the station designated by number 4. When l the called subscriber answers, a direct current circuit is closed on the line wires, and the relay 1204 acts, closes a latch circuit for its lower winding in 1236, opens points in the ringing circuit in 1235 and 1237, and opens the control circuit for relay 1201, at 1231 and 1232. Relay 1201 de-energizes accordingly, and releases relay 1202, after which a circuit is closed for release electro 1213, through 1223, 1227 and 1216 , and for the release electro 1215 of the auxiliary switch in 1230.

   The auxiliary switch, reaching its normal position, opens the circuit of relay 1205, which returns to rest, and in turn opens the circuit of electro 1215 in 1243. When the friction of the switch reaches the normal position, the contacts 1216

 <Desc / Clms Page number 38>

 open the circuit of the release electro 1213, and the contacts 1219 open the circuit of the relay 1204, which returns to idle:

   The relay 1207 also returns to idle following the. releasing relays 1202 and 1204, Relay 1204 also disconnects the earth of the test wiper from the connector at 1233, thus opening the circuit of relay 1101, which returns to idle and again connects the incoming wires to the conversation wires of the loop, Relay 1104 a, git through the subscriber loop, and again turns off the L18 lamp at il'-15. the annotator will then return key K16 to the normal position, and will establish a conversation connection with the subscriber by moving key K18 to the left.



   The arrangement of the bench contacts of the wiper 1220 is intended to produce selective ringing on a shared line for ten subscribers, with relay IL'08 intended to operate in series with relay 1205 to reverse the ringing connections.



  The monitoring of connections of this kind is in principle the same as for communications established from position B.



  In the case of waiting calls, the operator at position C will first establish communication with the calling subscriber and then with the called subscriber. It will be assumed that the subscriber located at set T, fig. 8 requested communication with a subscriber connected to a remote telephone network which is reached by the remote auxiliary telephone line which is reached by the auxiliary line terminating with the line switch LS2, fig. 3A.

   Operator C will choose a free junction circuit, for example the L1 junction circuit, and will move the conversation key k10 to the left, thus closing a circuit for the relay 602 through 608,515 and 534, The relay 602 then closes a circuit maintenance for itself = by 618, 609, 5123, relay 503 ;, to earth; it prepares the usual auxiliary restraint circuit

 <Desc / Clms Page number 39>

 at 619, and opens the direct connection between the incoming and outgoing branches of the junction circuit and connects them to the attendant position apparatus. Relay 603 is energized when operating key K10, and connects control wires 588 and 589 to relay 654, and wires 514 and 516 to relay 606.

   The attendant will now register the subscriber's number on the ES keypad and activate the power key, after which the earth on wire 29 will activate relay 508, and the earth on wire 30 will activate relays 506 and 505 , Relay 505 connects the branch wires leading to selector S2, to sender pulse contacts by circuits that can be easily traced, and relay 506, while closing points in the pulse circuit, closes a circuit of the earth, by 570, 558, 549,.



  573,576,628 relay 606, to the battery. The relay 606 is maintained by its upper winding, by 641, 627, 514 and 559; it closes the conversation threads of the lower branch leading to the selector S2m, through 638 and 644; it connects the earth, at 640, to the 650 wire; andconnect relay 605 to wire 651 at 643. The sender then transmits the recorded digits, in the usual manner, and these digits are used to operate the S2 selector, the TTS trunk transmission selector, and a connector, such as connector C , in order to connect the connection to the subscriber line, and to choose the ringing current desired to notify the said subscriber.

   However, the attendant does not force the connector to notify the subscriber at this time, but moves the key K7 to the left, after which the relay 504 is connected in series, in 568, to the relay 506, instead. relay 505, but it does not energize at this time, since the ground has been disconnected from wires 29 and 30. The sender control loop is moved to contacts 566 and 572, so that the series next pulse is transmitted through the upper branch of the junction circuit.

   The operator will then record the s digits

 <Desc / Clms Page number 40>

 necessary to choose a group of auxiliary lines
 EMI40.1
 terminating at the remote telephone office to which the subscriber is connected, for example, the number 3 which will activate the selector SI to choose a free auxiliary line, such as the one ending with the line switch LS2, fig. 3A. key will initiate the transmission operation in the manner previously described, relays 506, 504, 508 and 509 acting in the usual manner.

   When a free trunk line has been chosen, the attendant returns key K7 to the normal position and momentarily moves key K5 to the left, thus closing a circuit to actuate relay 504 to contacts 563, and connect the battery, by resistor 511, to the upper conversation wire of the junction circuit, by 541 and 561, This connection to the battery activates the bell relay of the. auxiliary line chosen, so as to notify the attendant at the remote office, and when it answers, the attendant in position C will send him the information necessary to establish the connection in the remote network.

   When this connection has been established and the called subscriber has been called, operator C will then warn the local subscriber by momentarily moving the key K6 to the right. The operation of the K6 key will close a circuit for relay 505, and the battery will be, connected, by 544, 583, 577, 538, 522, 617, 638, 649, the selector trotter, wire 435, to the relay of ringing of the transmission selector, which may be the TTS selector, fig.

     7. The ringing relay will then force the connector to send a dreaming current of the desired frequency to the called line to alert the subscriber. When the subscriber line is taken, earth will be reapplied to the supervisory wire in the usual way, thus actuating the relay.
 EMI40.2
 605 -included in iç., Croui t at junction, Le ¯tel, iS ¯6fl [closes. a circuit in 630 for the supervision lamp, 7.0,:. earth .. ..i .. i

 <Desc / Clms Page number 41>

 is disconnected from wire 651, when the subscriber answers, and lamp L10 is off. The operator can then withdraw from the connection and let the two subscribers talk to each other.

   Returning key K10 to the normal position will open the circuit of relays 602 and 603, which will then return to their normal position. Relay 602 directly connects the two branches of the junction circuit together, and connects relay 601 to the conversation wires. The primitive hold circuit for relays 654 and 606 will be opened by relay 603, but these relays will now be kept energized by earth, by means of contacts 653 of the K11 release key. Lamp L10 lights up when the first subscriber hangs up his receiver and earth is again applied to supervision wire 651.

   The remote operator will naturally receive the usual disconnection control signal from the subscriber connected to this office, and she will then apply a ringing current on the auxiliary line to give operator C the usual control signal of disconnection. The relay 601 will act under the effect of the ringing current applied to the auxiliary line, and will close a circuit, at 613, for the lamp L9, which will light up. Operator 0, noting that the L9 and L10 lamps are on, will release the connection by momentarily activating the K11 key. The operation of the key K11 opens the circuit of the relays 654 and 606, and the latter return to rest and open the circuits of the selectors S1 and S2, respectively. The switching apparatus is, under these conditions, released in the manner previously described.

   It will be noted that during the call, the operator can speak to one or other of the subscribers to the exclusion of the other by activating the respective secret listening keys, that is to say that, in order to speak with the subscriber who is reached by the selector SI and the upper branch of the junction circuit, the key K5 is moved to the right, and that for

 <Desc / Clms Page number 42>

 talk to the subscriber who is reached by the selector S2 and the. lower branch of the junction circuit key K6 is moved to the left. Relays 504 and 505 act accordingly. and disconnects one or the other of the branches of the circuit = cooked position.



   It will also be noted that the standby position circuit is arranged to be controlled by coins introduced into prepayment stations. The lines of these stations will be accessible by a series of inter-city switches which are suitable for this kind of service and are well known, so that they have not been shown. In calls like this, the connection will be. set by selector S2 and the lower branch of the liairson circuit. By moving the K8 key to the right or to the. left, a negative or positive disbursement and receipt control current will be applied to the lower branch conversion conductor.

   The operation of the coin mechanism will be indicated by a supervision lamp 16, during the operation of one or otter of the relays 510, 515, as the case may be. Releasing the connection in this case is the same as for the calls described above.



   An ancillary feature of the various trunk circuits is a device for carrying them occupied when an associated selector is locally occupied for repair, or for some other purpose. Referring to the junction circuit L (fig. 3). it will be noted that the test wire 381 starting from the selector S is connected, by contacts 393, to the test conductor 341 of the link circuit. ^ When selector 8 is busy, earth applied to the test lead in the usual way will carry the L junction circuit busy for line switches, such as LS. The L1 junction circuit is laid out a little differently. It also means that test leads 646 and 650 of the SL selectors

 <Desc / Clms Page number 43>

 and S2 are connected, by 632 and 639, respectively, to the lamp L10.

   This lamp will come on each time one or other of the selectors is locally occupied, and will indicate this condition to the attendant. In junction circuit L2, the test lead from selector S3, is connected, through 931, to relay 940. When the selector is carried busy, relay 940 acts and connects earth to test lead 433 to mark this circuit. auxiliary employed in the interurban selector benches. In junction circuit L4, test lead 1145 from selector S4, is connected by 1139 and 1166, to the associated annotation auxiliary line test lead. When the selector is occupied, ground on the selector and applied through the above circuit, will carry the busy auxiliary line for local selectors, such as selector S5.



    CLAIMS
1. A telephone system comprising a trunk switchboard 1 comprising trunk circuits to which incoming trunk lines can have access by non-digital switches, and terminating in a digital switch having access to trunk lines and services. subscriber lines.

** ATTENTION ** end of DESC field can contain start of CLMS **.


    

Claims (1)

2. A telephone system comprising an operator position comprising trunk circuits to which trunk lines can be accessed by non-digital switches, and an operator position comprising trunk circuits to which local subscriber lines can have access. access, a telephone system in which the trunk circuits at the two operator positions are terminated by digital switches with access to trunk lines. <Desc / Clms Page number 44> 3, A telephone system comprising an operator's position comprising trunk circuits to which trunk lines can have access and terminating in digital switches having access to trunk lines of local subscriber lines and trunk circuits at a second position operator, these latter trunk circuits also terminating in digital switches having access to trunk lines and local subscriber lines. 4, A telephone system comprising an operator position comprising a trunk circuit terminating in a switch having access to subscriber lines, and in which said trunk circuit is accessible, by non-digital switches, to the any of several trunk groups coming from different networks. 5, A telephone system comprising trunk circuits which can be accessed by paging switches, and in which each trunk circuit is provided with a key to answer the call, and a second key to force the call. seek switch to choose a different trunk circuit, 6. A telephone system having connections established by automatic switches by opening a loop circuit, the completion of a connection being characterized by the absence of connections to the battery and to earth at the far end of the loop circuit, with a relay being momentarily connected to the loop circuit at the point where the pulses are transmitted and after each series of pulses has been sent to determine if the connection has been established, 7. A telephone system comprising subscriber lines and in which calls made from a subscriber line to an operator position are intended to be kept independent. <Desc / Clms Page number 45> while the calling subscriber, while a digital switch is provided and can be controlled from the operating position to apply the desired kind of ringing current to alert the subscriber who has requested the call. . 8. A telephone system as claimed in 4, in which several junction circuits are provided as well as a common control apparatus with which these circuits are intended to be associated by the operation of a key reserved for the junction circuit. 9. A telephone system as claimed in 8, wherein the common control apparatus comprises a pulse sender for controlling the establishment of a connection, and wherein the signal transmitted to the called line is automatically initiated by the. common device acting under the effect of the termination of the connection, while a ringing key included in said common control device is intended to control the sending of a subsequent signal on the called line. 10. A telephone system as claimed in 1, 2, 3 or 4, comprising an operator position comprising trunk circuits to which trunk lines can have access, an operator position comprising trunk circuits to which local lines have access. subscribers can have access to, and an operator position to which the first and second operator positions can access, a telephone system in which all trunk circuits have access to trunk lines, while trunk circuits at the first and third operator positions also have access to local subscriber lines. 11. A telephone system as claimed in 5, in which the second key is also intended to release a connection from the trunk circuit. <Desc / Clms Page number 46> 12. A telephone system as claimed in 6, in which upon reestablishment of a connection circuit, changes made by one of the conversation wires waiting from the common control apparatus to to the last switch in the series, control the automatic application of a ringing current to the line called from the last switch in the series. 13. A telephone system as claimed in 1, 2, or 4, in which trunk circuits are intended to be divided in order to allow switching operations to be performed by the end of the link circuits comprising the digital switch. Including the other end, both ends of the link circuit being automatically reconnected when a connection has been established to the called line, 14. A telephone system as claimed in 13, EMI46.1 in which the junction circuit is automatically divided into two sections by the operation of the pulse transmitter used to control the adjustment of the switches. EMI46.2 automatic mutators. , 5 A telephone system as claimed in 4, in which a signal is provided on the switching board for each junction circuit, this Si-6 is intended to be activated when the corxes junction cireui on, waving is chosen, tanâis qLl'llD second corresponding signal of the troop to which the calling line belongs is eliminated to be activated whencluTOn answers â. l1a.ppe1 u.i has been done .. 16. A tcl Sphoniczu comrae rev nàio 6 in 6 e 12. in which the relay a.e line of one of the cpmmutatours is aetio11110, raI 'a winding. by means of pulses transmitted by the wires to the conversation in series. this relay being set> energized by aLlter - - - con- "energized. by a linked other ± ll ±) lJ1lflsÎ 1. . Tr61e when connection has 4t connected the called line. ' tr8le when the C D was. <Desc / Clms Page number 47> EMI47.1 17. A telephone system as claimed in 16, in which a control signal combined with the operator position is actuated under the effect of set-ups of said hold circuit. 18. A telephone system as claimed in 17, in. which the relay is disconnected from the control wire and maintained in a local circuit when the called subscriber answers. 19. A telephone system as claimed in 7, wherein said switch is arranged to disconnect the subscriber line from the operator position, to apply ringing current thereto, and is intended to release and connect to the operator. new subscriber line to. the operator position when the called subscriber answers. 20. A telephone system in principle as described and shown in the accompanying drawing. SUMMARY .- The invention relates to a telephone system comprising devices for establishing long distance connections by automatic switches, and is characterized mainly by the following points: The incoming long distance lines have access, through switches non-digital .. junction circuits leading to digital switches. r! a lisne is controlled .. The operation of the line circuits is controlled by keys .. 0 "The application of a ringing reduction on a called line is automatically initiated by a device placed at an aloperative position when the connection is established. ¯ 4. Devices are provided for ringing warning. , from an operator position, a calling subscriber connected to a subscriber line, & 2 3.s release 00 EMI47.2 established at this line dleborin6.