US1721920A - Telephone system - Google Patents

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US1721920A
US1721920A US53041A US5304125A US1721920A US 1721920 A US1721920 A US 1721920A US 53041 A US53041 A US 53041A US 5304125 A US5304125 A US 5304125A US 1721920 A US1721920 A US 1721920A
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relay
conductor
armature
switch
register
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US53041A
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Passmore William Oglesby
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Automatic Electric Inc
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Automatic Electric Inc
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q3/00Selecting arrangements
    • H04Q3/42Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker

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  • This invention relates to automatic or comprises one of the register controllers acsemi-automatic telephone systems andis an cessible to the registerselector RS together improvement in or modification of that set with the distributing frame DF, which is forth in the copending application of Richcommon to this register controller and a plu- 5 ardson ct al, filed February 25, 1924:, Serial rality of others.
  • the code register switches tion by stepping magnet SM and which are are of special construction which necessitates restored to normal position under the control 15 an additional controlling magnet and speof release magnet REL2 whosecircuit pass-es cial construction of the contact banks. through oil normal contacts 5iand is there-
  • the object of the present invention is to fore opened when the wipers reach their noremploy a common distributing frame and use mal position.
  • the input control switch disstandard type of switches in the register contributes the incoming impulse conductor 31 20 troller from the bank contacts of which leads to the various operating magnets of the regare connected to the distributing frame in ister cont-roller, the output control switch order to determine the translation required.
  • OCS is mechanically similar to the switch
  • one LS and the register selector RS,and its funcside of the common distributing frame is tion is to bring about the transmission of the proi'idod with a plurality of bus-bars or the various series of impulses in their proper like each connected up in a different manner, order, and to connect up the translating rewhile the other side is provided with a plulays TR-1TR-4 inclusive, Fig. 2 to the rality of contacts which are n'mltipled to the wipers of the code switches CS and CS1. bank contacts of a plurality of register The code switches CS and CS1, Fig.
  • a trunk circuit TC which is in of the code switches, such as the code switch serted in the trunk leading from the bank CS and CS and the three bus-bars E, B and contacts of the line switch LS to the selector EB, so that the oilice codes may be readily S, and the register selector RS individual to changed'and so that the changing of jumpers 50 the trunir circuit TC. at one point changes the'ofiice codes of a plu- The apparatus she 11 in Figs. 2, 3, and 4c, rality of register controllers.
  • the bus-bar E connected to earth potential, the bus-bar B to battery potential and the bus-bar EB to battery, and earth alternately by means of the interrupter 1.
  • armature 9 a circuit for slow release relay 7 which energizes and earths the release trunk conductor 18 at armature 11, thereby com pleting the usual holding circuit for the switching relay of the line switch LS.
  • Relay 7 also completes at armature 12 a circuit for switching relay 20 in series with stepping magnet 21 of the register selector RS and connects at armature 13 test wiper 28 to the junction of switching relay 20 and stepping magnet 21. Accordingly, the register selector RS operates in known manner to select an idle register controller.
  • switching relay 20 energizes; opens the test circuit and earths the test wiper 28 at armature 25,'t-hereby earthing conductor 32 of the seized register controller; connects up the impulsing conductor 81 at armature 26; and at armatures 23 and 24 connects the conductors 17 and 19 leading to the selector S over wipers 29 and 30 to a normally closed loop in the register controller including conductors 83 and Sat and aruiatures 100 and 101 in parallel of relays K and L respectively, Figure 1. According ly, the-line rela (not shown) of the selector S, Fig. 1 energizes and prepares the switch for operation in the usual manner.
  • the register controller Fig. 2 release relay 38 energizes ver the circuit: earth 25, 28. 32. 35, 102, 10?), 38, battery, responsive to earth heiug connected to conductor 32 by the switching relay 20 or the register sel ctor RS.
  • Release relay 36 upon energizin. removes earth potential fronrthe restoring conductor 57 and 106 at the back contact of armatures 4:3 and respectively, and the front contact of armature 43 earths the holdin conductor 107; and at a l prepares the incoming impulse circuit.
  • relay 36 closes a circuit for slow release relay 37 which energizes and prepares at armature 1-2 a circuit for magnet SM of the input control switch ICS. Accordingly when series relay 36 deenergizes at the end of the series of impulses, an impulse of current is transmitted to magnet SM during the interval required for relay 3'? to fall hack after its circuit is opened by relay 36. Magnet SM thereupon energizes and ad vances wipers and 56 into engagement with the second oi hank contacts.
  • wiper 55 and 56 of the input control switch ICS were advanced into engagement with the third set of bank contacts immediately following the termination of the rotary movement of the code switch CS, 2, wiper 55 completes the following energizing circuit for relay 39; earthed holding conductor 107, wiper in third position, relay 39 to battery.
  • Relay 39 upon energizing, closes the following circuits: At armature 1.8 closes the circuit for slow release relay M: battery 0', 18, 58, M, earth; at armature e19 prepares a c cuit for the two-step start relay J, at armature closes one point in an alarm circuit; at arma-v ture 51, prepares a circuit for the two step relay N; at armature 46, 416, 47 and 417 prepares circuits for the translating relays TRl to T134 respectively and at armature 52 extends ground from the bank of wipers 73 to conductor 150 by way of armatures 91-9 1, normal, thereby shunting relay M through armature 164 of relay L, preventing the operation of relay M for the time being.
  • Relay TR-l upon energizing first operates its armature 84 thereby completing the following locking circuit for itself: battery, upper winding of relay TR1, working contact and armature 8 1, conductor 151, resting contactand armature 165 to the ea rthed holding conductor 107.
  • Relay TR-1 now fully operates and at armature 80 opens its initial energizing circuit and at armature 91 removes the shunt from around relay M and earths'the first impulse stop conductor 14.0 in the bank of wiper 181 of the sending switch SEN over the following circuit: earth, wiper 7?), of the output control switch in normal position, conduct-or 13.8, working contact and armature 52, armature 91 and its working contact, armatures 88, 89, and 90 and their resting contacts to the first impulse stop conduc tor 140.
  • Relay'M upon energizing responsive to the said removal of the shunt from around its winding, completes the following circuitiior the two-step relay J earthed holding conductor 107, Fig.
  • the next pulse will now operate the stepping magnets SMI of thesending switch SEN over the operated contact 166 of relay J. T he operation of the sender will however be explained later.
  • Relay M also completes at armature 171 the following circuit for the two step relay N battery, upper winding of relay N, normal 175, conductor 153, operated 51, conductor 155, loop pulse springs 184, normal 17 1-, 0perateu 171, normal 168, conductor 15 1, wiper 72 to the earthed holding conductor 107.
  • the first pulse to relay N causes it to close its contacts 176 only, but immediately theloop pulse springs 1841 open, relay N fully operates over both its windings in series and-locks up to the earthed holding conductor 107 over armature 165 of stop relayL.
  • the complete operation of relay N places the loop pulse springs 184 across the conductors 33 and 3 1 in readiness for the operation of the selector S, Fig.
  • Relay L at armature 163 discon nects holding earth from the translating relays TR1TR 1 inclusive, thus allowing those held (relay TR-1 in the present case) to restoreto normal in readiness to be set again for the next digit upon the deenergization of relay L.
  • Relay L at armature 162 transmits an impulse to the stepping magnet SM2 of the'outputcontrol switch 008 over conductor 136 thus preparing it to advance its wipers 7075 inclusive, when the sending switchisrestored and stop relay L released.
  • relay L opens the locking circuit for relays J and N which deenergize and open the earth pulse circuit to the sending switch magnet SMl and the loop pulse circuit respectively.
  • Relay L also closes at armature 160 the following circuit for restoring the sending switch to normal position: earthed bank contacts in the bank or wiper 180 of the sending switch SEN, wiper 180, armature 160 and its working contact, interrupter contacts 158, stepping magnet SMl to battery.
  • wiper 180 opens the circuit for start relay K which deenergizes and opens the circuit of stop relay L which also deenergizes. Thesending switch is thus in its original condition and prepares to send the next series of impulses.
  • Relay TR3 operates its armature 86 in this circuit which completes a locking circuit for its upper winding whereupon relay TR-3 fully energizes.
  • Relay TR operates its armature 89 in this circuit which completes a locking circuit for its upper winding, whereupon relay TR-4L fully energizes.
  • relay M is shunted as before and falls back to disconnect relays J and N to prevent further impulses being sent and also to extend the shunting ground potential to the rotary magnet SM2 of the switch OGS through the resting contact and armature 169, conductor 137, wiper 74 in third position, interrupter contracts and stepping magnet SM2 to battery.
  • the output control switch is thus stepped until it reaches the seventh contact where its stepping circuit is opened and as relay M now energizes due to earth being removed troin conductor 137 by wiper 74: in seventh position, the circuits in the register controller are now in readiness to send the first nu1nerical digit. It may be pointed out here that since relay M is slow to release it will not de-- energize during the short period required by the translating relays TR1TR4 to be reset, when they restore between code digits. As the output control switch OCS is now in the seventh position, earth at wiper 73 is extended over wiper 115 of the thousands digitregister DR-1 to the sixth impulse stop conductor 1&5. If the hundreds digit l'has been transmitted to the hundreds digit register DR2 the sending switch is started over the circuit: earth, wiper 128 of DB2, conductor 131, seventh contact in the bank of wiper 72,;
  • theoutput control switch will advance to the eleventh position due to the stop relay L restoring.
  • position eleven the circuit for release relay 38 is opened andthis relay therefor deenergizcs.
  • earth potential is connected over conductor 85 and 32 to the test bank contact of the register selector BS in order to guard the register controller until its switches have fully returned to normal.
  • Release relay 38 upon deenergizing performs the following functions connects earth at armature 13 to the restoring conductors 57 and 105 thereby completing energizing cir cuits for the release magnets of the code switches CS and CS1, the digit registers DR1'to ZOE- 1 and the release magnet of the input control switch ICS, these switches are accordingly restored to normal and as is usual open theirenergizingcircuits in normal position.
  • Relay 38 also at armature disconnects earth from the holding conductor 107 thus releasing all operated relays in the register controller at armature a l completes the following circuit for switching relay 8 of the trunk circuit TC battery, relay 8, normally closed contacts controlled by armature 15, working contact and armature 2G, wiper 27, pulse conductor 31, relay 36, armature a l and its resting contact, conductor 20% to wiper 78 of the output control switch GUS and earth.
  • Relay 88 also connects earth at armature 45 to the seventh, eighth, ninth and tenth contacts inthe bank of wiper 7% of the switch OCS.
  • Switching relay 8 upon energizing, locks up to the release trunk 18, at armature l5, and at armatures 14 and 16 switches the calle ing side of the trunk circuit TC through to the connection set up by the register controller at armatures and 71 disconnects the register selector RS, whereupon switching relay 20 deenergizes and renders the register controller free to take another call. 7
  • TR 2 and TR4l together, 'lR 2TR-'l together, TR1, TR-S, TR4 together and Tl?;2, TR--1, Tlt4 together, thus obtaining sixteen combinations overthe two wipers 70 and 'i1.1
  • TR1- TR8 is made use ofto: cancel all numerical digits by operating the switching relay 8 at the end of an exchange code for example, when atoll operator is called.
  • the switching relay may be energized after the register-controller has sent out-one or more numerical digits and consequently the register controller may be taken into use for setting up connections to exchanges having a varying number of digits in the subscribers telephone numbers.
  • the calling party may be switched through to an operators position and the register controller re.- leased by making the necessary cross connections between dead numbers and the bus-bars on the common distributing frame.
  • these relays are provided to ensure that a correct impulse will always be delivered to the rotary magnet of the sending switch and to the automatic switches taken into use to establish the connection.
  • the relay J or the relay N as the case may be will not be fully operated and an alarm circuit will be completed over either the bank contact 168 of relay J or the bank contact 177 of relay N.
  • layN may be traced as follows: earthed hold- 7 ing conductor 107, armature 165 and its back contact, back contact and armature 177, con
  • the alarm circuit for relay J is as follows: earthed holding conductor 107, armature 165 and its back contact, armature 168 and its back contact, conductor 156, armature 50 and its working contact of relay 39,
  • relay M is'arranged to be energized at this time and as this relay not only drives the output control switch OCS into its correct position, but also disconnects both the erfith impulse springs 183 and the loop impulse springs 184, the sender cannot operate and no loop impulses can be transmitted during this period.
  • release relay 38 will deenergize and all operated relays and switches in the register controller will be restored to normal.
  • a telephone system employing automatic switches for setting up connections, directors including registering, translating and retransmitting apparatus, a distributing frame common to a plurality of said directors, an office register in each director having a plurality of wiper sets, means for operating the retransmitting means a plurality of times in accordance with the set position of the office register and in accordance with connections made at said distributing frame, the last named means including a set of storage relays
  • the alarm circuit for rer interposedbetween said'oflice register and the retransmitting means, and means advanced once for each operation ofthe retransmitting means for associating said storage relays with said wiper sets successively.
  • a sender including a counting switch, a set of permutational relays for controlling said switch, a plurality of circuit combinations for setting and resetting said relays, an office register for selecting a plurality of said circuit combinations, and a sequence switch for associating said circuit combinations with said relays successively.
  • a sender including a counting switch, a set of permutational relays for controlling said switch, a plurality of circuit combinations for setting and resetting said relays, an office register for selecting a plurality of said circuit combinations, a sequence switch for associating said circuit combinations with said relays successively, and a distributing frame. for facilitating changes in said circuit combinations.
  • a sender including a counting switch, a set of relays controlling said switch, a distributing frame comprising a plurality of sets of contacts and means by which any desired contacts of each set are'connected to the central oflice battery, and a sequence switch for associating said relays with a plurality of contact sets successively.
  • a pair of relays arranged to control the sender,'said relays being connected in series with each other and in series with a source of current and arranged so as not tooperate in series with each other, and means including the registering portion of said registersender for shunting either of said relays to permit the other to operate.
  • a sender including' a counting device, a pair of relays for controlling said device, a. current source, said relays being connected in series across the two poles of said current source and arranged not to operate in series witheach other, a control conductor extending from the junction of said relays, asecondary control conductor connected to one pole of said current source, a secondary control conductor connected to the other-pole of said current source, a third secondary control conductor, means for connecting said third secondary control conductor to tor, a second control conductor, and a third control conductor, a source of current, the first and second control'conductors being connected to the two poles respectively of SZI-iCt current source, a device for connecting the third control conductor alternately to the two poles of saldcurrent source, a secondary contil trol conductor, means for connecting said secondary control conductor with either of the first mentioned control conductors, and a. sending device variably operable accordin to which of the first mentioned control conductor
  • a first control conductor, a second control conductor, and a third control conductor a source of current, the first and second control conductors being connected to the two poles respectively of said current source, two secondary control conductors, means for connecting either of said secondary control conductors with any one of the lirst mentioned control conductors, and a sender variably operable in accordance with the connections between the first mentioned control conductors and said secondary control conductors.
  • each director including sending apparatus and a plurality of registering devices, an output control device for placing said sending apparatus under he control of said registering devices successively, and contacts on said output control device for initiating the release of the director and for guarding the same from seizure by said switching mechanism during its releasing operation.
  • a director switching devices for taking said director for use when the same is idle, a test conductor extending between said director and the test contacts of. said devices, a holding relay in said director connected to said release trunk conductor, a restoring circuit in said director, contacts on said holding relay for maintaining said restoring circuit open, a sending device in said director operable to transmit a plurality or digits, a step by step sequence switch having a set of wipers and cooperating contacts, means for advancing said sequence switch one step after each digit transmitted by said sender, and means including one of the wipers and its contacts for disconnecting said holding relay from the test conductor upon the advance of the sequence switch after the last digit is transmitted.
  • a register sender including registering devices for registering telephone numbers and a sending device responsive to settings of said registering devices to transmit digit impulses, hunting switches having access to said register sender.
  • a director In a director, a plurality of office registers operated simultaneously responsive to the office-designating portion of a number, a plurality of wipers on each register, a sender arran ed to be controlled first by the wipers of one register, and means normally eilective when all the wipers of the, first register have exercised their control for causing said sender to be controlled by the wipers-of the next oflice register.
  • a plurality of otlice re isters each havin a wi Jer a se uence switch having a contact bank, and conductors extending between all said wipersand a like number contacts in said bank.
  • a register sender for use in a multiotlice telephone system, a plurality of oflice registers each having a plurality of wipers, a sequence switch having a contact bank, and
  • a relay storage device including a pair of relays connected to a con ductor and responsive to two potentials, respectively,'means including a register for con necting either one or both of said potentials to saidcconductor to set said storage device, switching apparatus, and a control device effective to position said switching apparatus in accordance with the setting of said storage device.
  • a relay storage device including a pair of relays connected to a conductor and responsive to two potentials respectively, means including a register for connecting either one or both of said potentials to said conductor to set said storage device, an impulse sender, and means for operaging said impulse sender to send a train of impulses in accordancewvith the setting of said storage device.
  • a set of four relays for storing a digit, a distributing frame, an oflice egister having tWo Wipers for connecting said relays with said frame, and connections on said frame for setting all said relays over said two Wipers.

Description

Jul 23,- 1929.
.w. o. PAss oRE 1,721,920
TELEPHONE SYSTEM Original Filed Aug. 28,1925 4 Sheets-Sheet 1 J i w Z 3 Wu July 23, 1929. w. PASsMORE, 1,721,920
TELEPHONE SYSTEI n l fi 1925 4 Sheets-Sheet 3 -f ImrEfiIuP- l/LZLZZ1am Uglesby Fassmure 4 Sheets-Sheet 4 QY/70 L107 [T111571 E71" Mzlham 13 1557351 Fassmnre July 23, 1929. w. o. PASSMORE TELEPHONE s'ismi Origin a1 Filed Aug. .28, 1925 Patented July 23, 1929. lfizldl t lJhll'l'ED STATES FATENTQFFEQE;
WILLIAM OGLESBY PASSMOBE, O33 LIVERPOOL, ENGLAND, 'ASSIGNOR, BY MESNE AS- SIGNMENTS, T AUTGMATIC ELECTRIC INC., OF CHICAGO, ILLINOIS, A CORPORA-' 'IION OF DELAWARE.
,.,. TELEPHONE SYSTEM.
Application filed. August 28, 1925, Serial No. 53,04=1, and in Great Britain May 21, 1925. Renewed January 19, 1929. i
This invention relates to automatic or comprises one of the register controllers acsemi-automatic telephone systems andis an cessible to the registerselector RS together improvement in or modification of that set with the distributing frame DF, which is forth in the copending application of Richcommon to this register controller and a plu- 5 ardson ct al, filed February 25, 1924:, Serial rality of others.
N o. 69%,84-2. In that application a telephone Regarding the apparatus shown the line system is described employing register 0011- switch LS, the trunk circuit TC, the register trollers of the code translating type in which selector RS, and the selector S, may be of the a distributing frame is provided common to type shown in the above British patents. 60 a plurality of register controllers instead of The input control switch IGS, Fig. 2, is a simbeing individual as described in the British ple step by step switch having wipers and Patents 193,694t and 194,580 of 1923. In the 56 which are advanced in a forward direcabove application the code register switches tion by stepping magnet SM and which are are of special construction which necessitates restored to normal position under the control 15 an additional controlling magnet and speof release magnet REL2 whosecircuit pass-es cial construction of the contact banks. through oil normal contacts 5iand is there- The object of the present invention is to fore opened when the wipers reach their noremploy a common distributing frame and use mal position. The input control switch disstandard type of switches in the register contributes the incoming impulse conductor 31 20 troller from the bank contacts of which leads to the various operating magnets of the regare connected to the distributing frame in ister cont-roller, the output control switch order to determine the translation required. OCS is mechanically similar to the switch According to the present invention, one LS and the register selector RS,and its funcside of the common distributing frame is tion is to bring about the transmission of the proi'idod with a plurality of bus-bars or the various series of impulses in their proper like each connected up in a different manner, order, and to connect up the translating rewhile the other side is provided with a plulays TR-1TR-4 inclusive, Fig. 2 to the rality of contacts which are n'mltipled to the wipers of the code switches CS and CS1. bank contacts of a plurality of register The code switches CS and CS1, Fig. 2, are 3o switches, the wipers of the register switch mechanically well known Strowgerswitches, which records code digits being connected and their function isto register the otlice successively to a set of storage relays which digits in any called number preparatory to are operated according to connections made the transmission of the necessary code digits at the common distributing frame to cause to route the call to the desired oiiice. 35 the impulse sending apparatus to transmit The digit registers Dl tlDlt l, inclusive, successive series of impulses as predetcr- Fig. 3, are ea ch similar mechanically, to the mined by the operation of one or more of input control switch ICS and their function the storage relays. is to register the four subscriber digits of in order that the invention may be clearly any number. 4O understood and readily carried into effect, a The sending S' 'ltCh SEN, Fig. i, is sunrtelephone system in accordance with the inlar mechanically, to the output control switch vention will now be more fully described with OCS, and its function is to count off the imrcference to the annexed drawings comprispulses as they are being transmitted. ing Figures 1-4 inclusive. The distributing frame DI, Fig. 2, is con- 45 The apparatus shown in Fig. 1 comprises nected between the multiplied bank contacts portion of a trunk circuit TC which is in of the code switches, such as the code switch serted in the trunk leading from the bank CS and CS and the three bus-bars E, B and contacts of the line switch LS to the selector EB, so that the oilice codes may be readily S, and the register selector RS individual to changed'and so that the changing of jumpers 50 the trunir circuit TC. at one point changes the'ofiice codes of a plu- The apparatus she 11 in Figs. 2, 3, and 4c, rality of register controllers. The bus-bar E connected to earth potential, the bus-bar B to battery potential and the bus-bar EB to battery, and earth alternately by means of the interrupter 1.
The apparatus having been described generally a detailed description will now be given of its operation in recording and retransmitting a wanted number. For this purpose it is assumed that a calling party dials the number 336453 and that the number is reaehed by the digits 196%53. henthe receiver is removed at the call ing station the line switch LS operates in known manner to find an idle trunk circuit. Assuming that the trunk circuit .TC is the first one found idle line relay 6 will energize over bank contacts 2 and t and the calling partys loop. Relay 6. upon energizing, closes at armature 9 a circuit for slow release relay 7 which energizes and earths the release trunk conductor 18 at armature 11, thereby com pleting the usual holding circuit for the switching relay of the line switch LS. Relay 7 also completes at armature 12 a circuit for switching relay 20 in series with stepping magnet 21 of the register selector RS and connects at armature 13 test wiper 28 to the junction of switching relay 20 and stepping magnet 21. Accordingly, the register selector RS operates in known manner to select an idle register controller. hen an idle register controller is found, switching relay 20 energizes; opens the test circuit and earths the test wiper 28 at armature 25,'t-hereby earthing conductor 32 of the seized register controller; connects up the impulsing conductor 81 at armature 26; and at armatures 23 and 24 connects the conductors 17 and 19 leading to the selector S over wipers 29 and 30 to a normally closed loop in the register controller including conductors 83 and Sat and aruiatures 100 and 101 in parallel of relays K and L respectively, Figure 1. According ly, the-line rela (not shown) of the selector S, Fig. 1 energizes and prepares the switch for operation in the usual manner.
ln the register controller Fig. 2 release relay 38 energizes ver the circuit: earth 25, 28. 32. 35, 102, 10?), 38, battery, responsive to earth heiug connected to conductor 32 by the switching relay 20 or the register sel ctor RS. Release relay 36, upon energizin. removes earth potential fronrthe restoring conductor 57 and 106 at the back contact of armatures 4:3 and respectively, and the front contact of armature 43 earths the holdin conductor 107; and at a l prepares the incoming impulse circuit.
The above operations have all taken place responsive to the removal of the receiver at the calling station and the circuits are new in readiness for the first digit in the wanted number to he dialled. Accordingly, the calling party dials the first digit. three and the line relay 6 transmits three impulses to the vertical magnet- VM oi the code switch CS over the following circuit: earth 10, 26, 27, 31, 36, a l, 56, VM batter Tue vertical magnet VM responds to these impulses and raises its wipers a, i), c, (I, e and f opposite to the third level of bank contacts. Slow relay 36,
energized in series with the vertical magnet VM upon the first impulse beingtrans mitted to the latter, and, being slow to re lease, maintains its armature attracted through the series oi in'ipulses. At armature 4.0, relay 36 closes a circuit for slow release relay 37 which energizes and prepares at armature 1-2 a circuit for magnet SM of the input control switch ICS. Accordingly when series relay 36 deenergizes at the end of the series of impulses, an impulse of current is transmitted to magnet SM during the interval required for relay 3'? to fall hack after its circuit is opened by relay 36. Magnet SM thereupon energizes and ad vances wipers and 56 into engagement with the second oi hank contacts.
l Vhen the calling party dials the second digit this series of impulses is transmitted. over the previously traced circuit and wiper 56 out the switch ICS in second position'to the rotary magnet RM'ot the code switch CS. The wipers a, 5, 0, cl, 0 and f, are now rotated into engagement with the third set of bank contacts in the third level, which contacts are assumed to be the contacts 61-66 inclusive. Since relay 36 is again energized during the transmission of this series of impulses, magnet 52 will be operated again and wipers and 56 will be advanced to third position. ll iper 55, upon coming into engagement with the third associated bank contact, completes a circuit for relay 39 which initiates the send ing operation, and the sender SEN, Fig. 4L, starts to out the first of the oi'lice code digits, as will be subsequently explained.
Responsive to the tour remaining series of impulses con'iprising six, four, live and three impulses, respectively, the digit registers DRLDR JE inclusive, 3, are operated over conductors 108111 respectively, the wipers 55 and 56 of the switch ICS being advanced one step at the end oi": each series of impulses as previously described. V
Considerin now the code switch CS. it will be remembered that the wipers a, Z), c, a, (a, and e f are in engagement with the bank contacts 61-66 respectively, and it may he pointed out here that the subsequent description will show how the wipers m-f control the valueand number of the code digits in accordance with the cross connections made at the distributing bars. Accordingly, as will be described hereina'l'ter, two code digits 1 and 9 will be transmitted owing to the connections made to these bus-bars.
Returning now to the point at which wipers 55 and 56 of the input control switch ICS were advanced into engagement with the third set of bank contacts immediately following the termination of the rotary movement of the code switch CS, 2, wiper 55 completes the following energizing circuit for relay 39; earthed holding conductor 107, wiper in third position, relay 39 to battery. Relay 39, upon energizing, closes the following circuits: At armature 1.8 closes the circuit for slow release relay M: battery 0', 18, 58, M, earth; at armature e19 prepares a c cuit for the two-step start relay J, at armature closes one point in an alarm circuit; at arma-v ture 51, prepares a circuit for the two step relay N; at armature 46, 416, 47 and 417 prepares circuits for the translating relays TRl to T134 respectively and at armature 52 extends ground from the bank of wipers 73 to conductor 150 by way of armatures 91-9 1, normal, thereby shunting relay M through armature 164 of relay L, preventing the operation of relay M for the time being.
Referring now to the distributing frame DF it will be seen that earth is place on wiper a; and that battery and earth is placed alternately on wiper cl. Responsive to earth being connected to wiper a the following circuit is completed for the translating relay TR1:earth, bus-bar E, jumper and bank contact 61, wiper a, conductor 200, first contact in the bank of wiper 70 of the output control switch OCS, wiper 70, conductor 250, armature 251 and its resting contact, conductor 201, working contact and armature 16, armature 80 and its resting contact to the lower winding of relay TR1 and battery. Relay TR-l upon energizing first operates its armature 84 thereby completing the following locking circuit for itself: battery, upper winding of relay TR1, working contact and armature 8 1, conductor 151, resting contactand armature 165 to the ea rthed holding conductor 107. Relay TR-1 now fully operates and at armature 80 opens its initial energizing circuit and at armature 91 removes the shunt from around relay M and earths'the first impulse stop conductor 14.0 in the bank of wiper 181 of the sending switch SEN over the following circuit: earth, wiper 7?), of the output control switch in normal position, conduct-or 13.8, working contact and armature 52, armature 91 and its working contact, armatures 88, 89, and 90 and their resting contacts to the first impulse stop conduc tor 140. Relay'M, upon energizing responsive to the said removal of the shunt from around its winding, completes the following circuitiior the two-step relay J earthed holding conductor 107, Fig. 3, wiper 72 of the output control switch OGS in normal position, conductor 15%, normal 163, operated 170, pulse springs 188, conductor 50, operated 10, conductor 60, normal 166, upper winding of relay J to battery. The first earth pulse to relay J will cause it tooperate its contacts 167 only, but immediately this earth pulse ceases (i. e.', the pulse springs 183 open) relay 5 fully operates over both its windings in series and locks up tothe holding conductor 107 over contacts 165 of stop relay L.
The next pulse will now operate the stepping magnets SMI of thesending switch SEN over the operated contact 166 of relay J. T he operation of the sender will however be explained later.
Relay M also completes at armature 171 the following circuit for the two step relay N battery, upper winding of relay N, normal 175, conductor 153, operated 51, conductor 155, loop pulse springs 184, normal 17 1-, 0perateu 171, normal 168, conductor 15 1, wiper 72 to the earthed holding conductor 107. The first pulse to relay N causes it to close its contacts 176 only, but immediately theloop pulse springs 1841 open, relay N fully operates over both its windings in series and-locks up to the earthed holding conductor 107 over armature 165 of stop relayL. The complete operation of relay N places the loop pulse springs 184 across the conductors 33 and 3 1 in readiness for the operation of the selector S, Fig. 1 The further operation of theloop pulse springs will not have any effect at this stage upon the selector S as they are short circuited at armature 100 of start relay K. The rotary magnet SM of the sending switch was set in motion as previously explained and steps its wipers 180 and 181 on one step. Immediately wiper 180 makes one step it completes the following circuit for start relay K: battery K, 180, earth. Start relay K' upon energizlng removes at armature. 100 the short circuit, about the loop impulse springs 18 1 and the line relay oi theselector S is thus held over the loop pulsespring 18 1. The next operation of the earth pulse springs 183 operates the sending switch one more step and simultaneously the loop pulse springs transmit one impulse to the line relay of the selector S, thus causing it to step up, hunt, and switch on to the first level.
Immediately wiper 181 of the sending the same. Relay L at armature 163 discon nects holding earth from the translating relays TR1TR 1 inclusive, thus allowing those held (relay TR-1 in the present case) to restoreto normal in readiness to be set again for the next digit upon the deenergization of relay L.
Relay L at armature 162 transmits an impulse to the stepping magnet SM2 of the'outputcontrol switch 008 over conductor 136 thus preparing it to advance its wipers 7075 inclusive, when the sending switchisrestored and stop relay L released. At armature 165 relay L opens the locking circuit for relays J and N which deenergize and open the earth pulse circuit to the sending switch magnet SMl and the loop pulse circuit respectively. Relay L also closes at armature 160 the following circuit for restoring the sending switch to normal position: earthed bank contacts in the bank or wiper 180 of the sending switch SEN, wiper 180, armature 160 and its working contact, interrupter contacts 158, stepping magnet SMl to battery.
When the sending switch SEN is in home position wiper 180 opens the circuit for start relay K which deenergizes and opens the circuit of stop relay L which also deenergizes. Thesending switch is thus in its original condition and prepares to send the next series of impulses.
Immediately stop relay L restores, the stepping magnet SM2 01"" the output control switch OCS releases and steps the switch to second posltion, whereit preparesthe clrcults to send the second digit. As soon as the output control switch sets its wipers in its second position a fresh set up of the translating relays TR1TR-4 inclusive occurs as follows: The manner in which the register controller sends the second code digit is identical with that described for the first code digit, with the following exceptions: earth and battery is connected to the codeswitch wiper (Z by means of the interrupter I and the translating relays TR3 and TR t are energized as follows earth from interrupter I, bus-bar EB,
' 'um yet to bank contact 64 wi or (5 conductor 202, output control switch wiper 71 in second position, conductor 253, resting cont-act and armature 252, conductor 203, working contact and armature 47, armature 82 and its resting contact, lower winding of relay TR3 to battery. Relay TR3 operates its armature 86 in this circuit which completes a locking circuit for its upper winding whereupon relay TR-3 fully energizes. The energizing circuit for relay TR4= is as follows: battery frominterrupter I, bus-bar EB, jumper to bank contact G hwiper (Z, output control switch wiper71in second position,conductor 253,1'esting contact and armature 252, conductor 203, working contact and armature 47, armature 83 and its resting contact to the lower winding of relay TR4 and earth. Relay TR operates its armature 89 in this circuit which completes a locking circuit for its upper winding, whereupon relay TR-4L fully energizes.
trol circuit 33, 34, and restores to its home position as already described the output control switch OCS being steppedinto its thlrd position. As there are no cross connections between the bus-bars E, B and EB and the bank contacts upon which the wipers b, c, e and f are resting, due to the fact thatronly two code digits are to be sent out, the following operations take place:
All the translating relays being now in normal position, relay M is shunted as before and falls back to disconnect relays J and N to prevent further impulses being sent and also to extend the shunting ground potential to the rotary magnet SM2 of the switch OGS through the resting contact and armature 169, conductor 137, wiper 74 in third position, interrupter contracts and stepping magnet SM2 to battery.
The output control switch is thus stepped until it reaches the seventh contact where its stepping circuit is opened and as relay M now energizes due to earth being removed troin conductor 137 by wiper 74: in seventh position, the circuits in the register controller are now in readiness to send the first nu1nerical digit. It may be pointed out here that since relay M is slow to release it will not de-- energize during the short period required by the translating relays TR1TR4 to be reset, when they restore between code digits. As the output control switch OCS is now in the seventh position, earth at wiper 73 is extended over wiper 115 of the thousands digitregister DR-1 to the sixth impulse stop conductor 1&5. If the hundreds digit l'has been transmitted to the hundreds digit register DR2 the sending switch is started over the circuit: earth, wiper 128 of DB2, conductor 131, seventh contact in the bank of wiper 72,;
conductor 154, armature 163, armature 170 and its working contact, earth pulse springs 183, conductor 59, working contact and armature 19, conductor 60, armature 166 to relay J and battery. Relay J as before comnletes a circuit at 166 for the stepping inagnet SMl of the sending switch SEN. Under these circumstances the subsequent operations of the sending switch are identical with those explained for the sending of the code digits; The impulses of the first numerical digit are thus transmitted over the output r if the tens digit control circuit 35, 34 to the switches taken into use. At the end of the transmission of this series of impulses the output control switch is advanced to eight position whereupon earth at wiper 73 is extended over wiper 116 of the hundreds digit register DR 2'to the fourth impulse stop conductor 143, and
has been recorded on the'register DR3 four impulses will be transmitted b the sendin swi ch. The tens and units b dig are transnntted n a similar manner to the thousands and hundreds digits.
Immediately the last digit has been sent, theoutput control switch will advance to the eleventh position due to the stop relay L restoring. In position eleven the circuit for release relay 38 is opened andthis relay therefor deenergizcs. In the eleventh to twentytifth positions of wiper 75 earth potential is connected over conductor 85 and 32 to the test bank contact of the register selector BS in order to guard the register controller until its switches have fully returned to normal.
Release relay 38 upon deenergizing performs the following functions connects earth at armature 13 to the restoring conductors 57 and 105 thereby completing energizing cir cuits for the release magnets of the code switches CS and CS1, the digit registers DR1'to ZOE- 1 and the release magnet of the input control switch ICS, these switches are accordingly restored to normal and as is usual open theirenergizingcircuits in normal position. Relay 38 also at armature disconnects earth from the holding conductor 107 thus releasing all operated relays in the register controller at armature a l completes the following circuit for switching relay 8 of the trunk circuit TC battery, relay 8, normally closed contacts controlled by armature 15, working contact and armature 2G, wiper 27, pulse conductor 31, relay 36, armature a l and its resting contact, conductor 20% to wiper 78 of the output control switch GUS and earth. Relay 88 also connects earth at armature 45 to the seventh, eighth, ninth and tenth contacts inthe bank of wiper 7% of the switch OCS. This connection has no effect in the present case, but would serve to restore the output control switch to normal in the event of the calling party abandoning the call after dialling the exchange code and be fore completely dialling the numeral digits. Switching relay 8, upon energizing, locks up to the release trunk 18, at armature l5, and at armatures 14 and 16 switches the calle ing side of the trunk circuit TC through to the connection set up by the register controller at armatures and 71 disconnects the register selector RS, whereupon switching relay 20 deenergizes and renders the register controller free to take another call. 7
In the foregoing description only two exchange code digits were sent out and attention is drawn to the fact with the apparatus shown it is possible to send out any numberof codes up to six. The code switch US will take care of any three codes and the code switch CS1 will take care of a like number by means of its six wipers g, h, i, j, is, and Z. A j
-Bet'erringv now to the translating relays TR-1 to TR1 it will beseen that with relay Tl'l1 energized alone that the first impulse stop conductor 140 is'earthed; with rel ys Silt-1 and CPR- 2 the second impulse stopv conductor 141; TB1 and TR3 the third impulse stop conductor142; TR1 and TR-4 thefourth impulse sto'p'conductor 14:3; Tll2 the fifth impulse stop conductor 14 1; TR-2 and TR3 the sixth impulsestop conductorll-S; TR2 and TR4 the seventh impulse stop conductor 146; TR3 the eighth in'ipulse stop conductor 1 1; TR3 and Tlt l the ninth impulse stop conductor 148; flR4 the tenth impulse stop conductor 149, a further combination is obtained when all the relays are in normal position. By the use of the bus-bars earth, batteryand battery and earth alternately it is'possible to energize relays TR1TR3 together, TR--1,
TR 2 and TR4l together, 'lR 2TR-'l together, TR1, TR-S, TR4 together and Tl?;2, TR--1, Tlt4 together, thus obtaining sixteen combinations overthe two wipers 70 and 'i1.1 One of these combinations- TR1- TR8 is made use ofto: cancel all numerical digits by operating the switching relay 8 at the end of an exchange code for example, when atoll operator is called. As-
suming that the code required to route ,a call to an operator is 78 then the bank contacts engaged by wipers a and 5 Wlll be connected to bus-bar B in order to energize relays TR2 and Tlt l tobring about the transmission of eight impulses The bank contact engaged by wiper (Z will be connected to bus-bar E in order to energize relay TR3 to bring about the transmission of seven impulses. N ow in order to bring about the operation of switching-relay 8 after the reception of the code digits 7 8, the translating relaysTR1, TR2 and TR3 must be energized with the output control switch wipers 70, 71, in' third position. Accordingly the bank contacts engaged by wipers e and are connected to busbars EB and E respectively- With relays TR'1, Tlt-2 and TR-Z) energized earth is connected to conductor 205 and switching relay 8 energizes as before over conductor 31 to switch the calling party through to the operator and to bring about the release of the register controller.
It will. be appreciated by those skilled in theart that with the additional combinations possible with the translating relays that the switching relay may be energized after the register-controller has sent out-one or more numerical digits and consequently the register controller may be taken into use for setting up connections to exchanges having a varying number of digits in the subscribers telephone numbers. Moreover in case a call ing party dials a dead number the calling party maybe switched through to an operators position and the register controller re.- leased by making the necessary cross connections between dead numbers and the bus-bars on the common distributing frame.
Referring to the two step relays J and N, Figure 3, these relays are provided to ensure that a correct impulse will always be delivered to the rotary magnet of the sending switch and to the automatic switches taken into use to establish the connection.
' In case either the earth pulse springs 183 or the loop pulse springs 184 fail to function correctly due to being short circuited or disconnected, the relay J or the relay N as the case may be will not be fully operated and an alarm circuit will be completed over either the bank contact 168 of relay J or the bank contact 177 of relay N. layN may be traced as follows: earthed hold- 7 ing conductor 107, armature 165 and its back contact, back contact and armature 177, con
ductor 156, armature 50 and its working contact, relay 39, Fig. 2, conductor 157, working contact and armature 172' to the alarm circuit conductor AC. The alarm circuit for relay J is as follows: earthed holding conductor 107, armature 165 and its back contact, armature 168 and its back contact, conductor 156, armature 50 and its working contact of relay 39,
Fig. 2, conductor 157, working contact andarmature 17 2 of relay M to the alarm circuit conductor AC.
In order to ensure that noimpulse will be transmitted during the change from the transmission of the code digits to the transmission of numerical digits, relay M is'arranged to be energized at this time and as this relay not only drives the output control switch OCS into its correct position, but also disconnects both the erfith impulse springs 183 and the loop impulse springs 184, the sender cannot operate and no loop impulses can be transmitted during this period.
In case the calling party abandons the call at any stage of a connection, release relay 38 will deenergize and all operated relays and switches in the register controller will be restored to normal.
lVliat is claimed is:
1. In a telephone system employing automatic switches for setting up connections, directors including registering, translating and retransmitting apparatus, a distributing frame common to a plurality of said directors, an office register in each director having a plurality of wiper sets, means for operating the retransmitting means a plurality of times in accordance with the set position of the office register and in accordance with connections made at said distributing frame, the last named means including a set of storage relays The alarm circuit for rer interposedbetween said'oflice register and the retransmitting means, and means advanced once for each operation ofthe retransmitting means for associating said storage relays with said wiper sets successively.
2. In a director, a sender including a counting switch, a set of permutational relays for controlling said switch, a plurality of circuit combinations for setting and resetting said relays, an office register for selecting a plurality of said circuit combinations, and a sequence switch for associating said circuit combinations with said relays successively.
3. In a director, a sender including a counting switch, a set of permutational relays for controlling said switch, a plurality of circuit combinations for setting and resetting said relays, an office register for selecting a plurality of said circuit combinations, a sequence switch for associating said circuit combinations with said relays successively, and a distributing frame. for facilitating changes in said circuit combinations. Y
4. In a director, a sender including a counting switch, a set of relays controlling said switch, a distributing frame comprising a plurality of sets of contacts and means by which any desired contacts of each set are'connected to the central oflice battery, and a sequence switch for associating said relays with a plurality of contact sets successively.
5. In a register sender, a pair of relays arranged to control the sender,'said relays being connected in series with each other and in series with a source of current and arranged so as not tooperate in series with each other, and means including the registering portion of said registersender for shunting either of said relays to permit the other to operate.
6. In a telephone system, a sender including' a counting device, a pair of relays for controlling said device, a. current source, said relays being connected in series across the two poles of said current source and arranged not to operate in series witheach other, a control conductor extending from the junction of said relays, asecondary control conductor connected to one pole of said current source, a secondary control conductor connected to the other-pole of said current source, a third secondary control conductor, means for connecting said third secondary control conductor to tor, a second control conductor, and a third control conductor, a source of current, the first and second control'conductors being connected to the two poles respectively of SZI-iCt current source, a device for connecting the third control conductor alternately to the two poles of saldcurrent source, a secondary contil trol conductor, means for connecting said secondary control conductor with either of the first mentioned control conductors, and a. sending device variably operable accordin to which of the first mentioned control conductors the secondary control conductor is connected with. i
, 8. In con bination, a first control conductor, a second control conductor, and a third control conductor, a source of current, the first and second control conductors being connected to the two poles respectively of said current source, two secondary control conductors, means for connecting either of said secondary control conductors with any one of the lirst mentioned control conductors, and a sender variably operable in accordance with the connections between the first mentioned control conductors and said secondary control conductors.
9. In a telephone system, a plurality of directors, switching mechanism for selecting idle directors, each director including sending apparatus and a plurality of registering devices, an output control device for placing said sending apparatus under he control of said registering devices successively, and contacts on said output control device for initiating the release of the director and for guarding the same from seizure by said switching mechanism during its releasing operation.
10. In a telephone system, a director, switching devices for taking said director for use when the same is idle, a test conductor extending between said director and the test contacts of. said devices, a holding relay in said director connected to said release trunk conductor, a restoring circuit in said director, contacts on said holding relay for maintaining said restoring circuit open, a sending device in said director operable to transmit a plurality or digits, a step by step sequence switch having a set of wipers and cooperating contacts, means for advancing said sequence switch one step after each digit transmitted by said sender, and means including one of the wipers and its contacts for disconnecting said holding relay from the test conductor upon the advance of the sequence switch after the last digit is transmitted.
11. In a register sender including registering devices for registering telephone numbers and a sending device responsive to settings of said registering devices to transmit digit impulses, hunting switches having access to said register sender. means for causing one of said hunting switches to seize said register sender and for subs quently operating the same, and means in said register sender responsive to the retransmission of the last stored digit for immediately rendering said register sender busy to the other hunting switches, for subsequently causing said hunting switch to free the said register sender, and for maintaining said register sender busy to the other hunting both of said re istors in accordance with their set position for setting up said train of switches.
14. In combination, two office registers each having wipers, said wipers being associated together in sets, means for operating said otfice registers inresponse to the same otlice-designating character in a telephone number, a switch controller, and means for operating said controller under the joint control oi the wipers of one set and for then operating it under the joint control of the wipers of the other set. I
15. In a director, a plurality of ofiice registers operated simultaneously responsive to the others-designating portion of a number, a plurality of sets of wipers on each register,
same has been restored to itsnorinal a sender adapted to be controlled jointly by the wipers of the first set, and a sequence switch for shittingthe control to the other sets in turn.
' 16. In a director, a plurality of office registers operated simultaneously responsive to the office-designating portion of a number, a plurality of wipers on each register, a sender arran ed to be controlled first by the wipers of one register, and means normally eilective when all the wipers of the, first register have exercised their control for causing said sender to be controlled by the wipers-of the next oflice register.
17. In a register sender or use in a multioi'lice telephone system, a plurality of otlice re isters each havin a wi Jer a se uence switch having a contact bank, and conductors extending between all said wipersand a like number contacts in said bank.
18. In a register sender for use in a multiotlice telephone system, a plurality of oflice registers each having a plurality of wipers, a sequence switch having a contact bank, and
conductors connecting all said wipers'respeo V a control device operated to exercise a control 7 in accordance With the setting of said device.
20. In combination, a relay storage device including a pair of relays connected to a con ductor and responsive to two potentials, respectively,'means including a register for con necting either one or both of said potentials to saidcconductor to set said storage device, switching apparatus, and a control device effective to position said switching apparatus in accordance with the setting of said storage device.
21. In combination, a relay storage device including a pair of relays connected to a conductor and responsive to two potentials respectively, means including a register for connecting either one or both of said potentials to said conductor to set said storage device, an impulse sender, and means for operaging said impulse sender to send a train of impulses in accordancewvith the setting of said storage device.
22. In a director, a set of four relays for storing a digit, a distributing frame, an oflice egister having tWo Wipers for connecting said relays with said frame, and connections on said frame for setting all said relays over said two Wipers.
WILLIAM oeLEsBY PASSMORE.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2680781A (en) * 1949-11-08 1954-06-08 Bell Telephone Labor Inc Translating arrangement

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2680781A (en) * 1949-11-08 1954-06-08 Bell Telephone Labor Inc Translating arrangement

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