US2431321A - Multioffice telephone system - Google Patents

Multioffice telephone system Download PDF

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Publication number
US2431321A
US2431321A US507469A US50746943A US2431321A US 2431321 A US2431321 A US 2431321A US 507469 A US507469 A US 507469A US 50746943 A US50746943 A US 50746943A US 2431321 A US2431321 A US 2431321A
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Prior art keywords
relay
circuit
earth
winding
impulse
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US507469A
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English (en)
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Fernand P Gohorel
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International Standard Electric Corp
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International Standard Electric Corp
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/42—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/60—Semi-automatic systems, i.e. in which the numerical selection of the outgoing line is under the control of an operator

Definitions

  • the present invention relates to various improvements in telephone systems, and particularly in systems comprising several exchanges connected by cables, and in which communication between subscribers of diierent exchanges may be established Wholly by the operator of thev outgoing exchange without the intervention of the'incoming operator, or of the operators of the intermediate exchange or exchanges.
  • dialling impulses which are transmitted in the form of interruptions of a dialling current, become effective at the incoming exchange where theyare recorded during the interruption of the current, only when the dialling current is re-established.
  • Another characteristic of the invention consists in thatwhen a dialling impulse Whichgis transmitted in the form of an interruption of a dialling current has been recorded, the recording device can record the/next impulse only when the previous impulse has become effective and has thus caused a particular operation or signalling function.
  • Another characteristic of the invention consists in that the device rendering the impulses'efective, operates only if the duration of the interruption of the dialling current does not exceed a predetermined maximum value.
  • Another characteristic of the invention is that a series relay in the device which renders the impulseseiective can operate only if operating-im ⁇ pulses are received.
  • Another characteristic of the invention consists in that the devices on which the impulses must be received can participate in the hunting for the calling line only after a preliminary local test under normal conditions of operation of their detection device and of the impulse relay which is associated with said detection device.
  • Another characteristic of the invention consists in that the signal indicating that the impulse transmission is at an end is constituted by the stoppage of the transmission of the dialling current from the transmitting station.
  • ⁇ Another characteristic of the invention consists in the use at the transmitting station, and atvthe receiving station, of a single control switch in order to produce the diierent transmissions of low frequency signalling or supervisory currents.
  • Another characteristic of the invention consists in that each operator has at her disposal two means of access to the trunks leading to the incoming exchange:
  • the establishment of the connection through a first channel causes lthe trans- 6 Claims. (Cl. 179%27)
  • e fromlthef outgoing exchange o f a pre-determined signal which veffects, the necessary s vvitc'loing operations ⁇ to" connect at the incoming exchange, the circuit toga predetermined operai tor; or'subscriber.
  • connection -th'roughja secondV channel does not produce any predeterminedoperation; this operation canbe-'eiiectedonly when theoperator works her Antner characteristic-ofithe-invention consists that when f theV operatorgjisl'connectedwith a junction circuit over the first chfannelya momentary Aemission of the dialling current without interruptionsl ⁇ ill send a predetermined signal from the outgoing exchange; H
  • Y Fig.' 1 represents'fa -portionof agcord pair of an perators positionnecessary 'fior understanding the operation of the device; f Y t Fig'. Z'isthe outgoingequipment vof va circuit between exchanges; l v I Figfv is the incoming equipment'vof a circuit between exchanges; 1
  • Fig. l is an impulse recordiigdevice associated With the incomingH equipment; Figi 5"i's'a detector Vor'receiving device for transforming the alternating current impulses received into directcurrent impulses;
  • Fig'. 6 isthe equipment of 'an inter-'cnice trunk leading toA the operatorls position I at the incoming exch'ang;' d l f Fig. 7 showsa 'device-for'establishinga connection between'the incoming'equipment of an interoiiice-trunk and the automatic equipment of the incoming exchange; and'y i? Fig. 8 shows the mannerin which Figs. 1 to 7 should be connected.
  • winding of relay 22 is ⁇ completed: earth, TI93, TZQI, R2I I, lower winding of 22 and-battery.
  • the operator of the outgoing exchange plugs the cord pair of Fig. l into the jack J of the equipment of Fig. 2.
  • Relay is energized through its lower winding in the circuit: earth, lower winding of 4,R5 I, jack J, sleeve of plug C, windings in series of relay I and battery.
  • relay I cannot attract its armature.
  • Relay ll closes at T42 the starting circuit of cams C1 and C2.
  • TM it closes the circuit of relay f which opens at RM' the circuit of the dis- Vcuit of the windings in series of relay 5 through the windings of relay I.
  • Relay 5 pulls up, but relay I cannot be energized on account of the At T62, relay 6 completes the circuit of relay 9 which pulls up.
  • relay 5 completes the following circuit of relay l: earth, RGI, T52, winding of l, and battery.
  • relay .'I completes its hold# ing circuit to earth of R84.
  • it completes the following stepping circuit of the control switch: earth, cam C2, T'II, RIUI, T61, contact of wiper e of the control switch in position O, stepping magnet Cm of the control switch.
  • the control switch advances one step and passes to position I. From that time said con- IlO trol switch makes a complete rotation, the circuit of the magnet CM being closed over cam C2 by wiper e in the positions I to I0, and by wiper f in the positions I I to 2
  • control switch When the control switch leaves its normal position O, it opens the line wires L1 and L2 of the equipment of Fig. 2 and connects them through wipers a and b, and in positions I to I0 to the low frequency current generator GeI.
  • a calling impulse is thus sent over conductors LI-LZ which, at the incoming exchange is received by the relay I8.
  • relay I8 completes the circuit of the lower winding of relay I9 which pulls up, and of the winding of relay 20 which pulls up a The following circuit ofthe lower When the relay 22 pulls up, the starting circuit of the registers is completed through T222, and R232 and wire 52. It will be assumed that the first free register in engagement with the equipment of Fig. 3 is that of Fig. 4.
  • Y Y Relay 5I connects at Tl andTEIS thevoice frequency current generator G63 to the input The Ydevice Dr thus ⁇ detects Ycurrent from 4 the generator Ge3 causing the energization of relay 53.
  • relay 53 completes the circuit of the upper winding of relay 52 through T5I I.
  • Relay 52 pulls up and at T5II completes its holding circuit on its lower winding; at R524 and R522, it disconnects the generator G63 from the .detector Dr whereupon relay :53 fa-lls off.
  • Relay 50 pulls up and at 'T591 closes lits holding circuit to earth Valo-- plied to wire 24', at T282 by relay 28; at T14, it opens the holding circuit of relay 26 which falls back. At'T502, it applies earth to wire 23 thus completing the circuit of the lower winding of vrelay 30 which pulls up.
  • the direction of the upperwinding of Yrelay 39 is such that its uX is opposed to that of .the
  • relay 32 When relay 32 pulls up, Ithe register and the detection equipment are connected'to the incoming equipment.
  • relay I8 (Fig. 3) falls back.
  • the lower winding of relay 2.! no longershortcircuited and this-re lay pulls up in series with the ylower winding of relay 22.
  • circuitY of relay 2li is completed: earth, T253, winding of .relay 24,
  • the control switch will thus advance under the action of the impulses of the cam C3.
  • relay 28 When the wipers of C04 arrive on a free equipment for connection with the automatic. exchange, such as that of Fig. 3, relay 28 is energized in the circuit: earth, T212 (relay 21 has pulled up on its lower winding through R265 and T251) windings in series of 28, wiper T, wire 53', R635, R682 and battery through the automatic equipment.
  • the relay 23 in pulling up, opens at R282 the circuit of magnet Cm4.
  • the wipers of C04 stop on the contacts to which the equipment of Fig. 7 is connected.
  • the circuit of relay 26 is completed through: earth, T251, T282, winding of 26 and battery.
  • Relay I1 releases when wiper a of the control switch passes position 1.
  • Relay I9 releases a moment after the end of the reception of the calling impulse.
  • Relay I2 connects the line conductors L1 and L2 over T25I and T259, and the wires a and b towards the register and the detector device.
  • relay 64 of Fig. 7 The following circuit of relay 64 of Fig. 7 is completed: battery, winding of 64, R632, wire 5I', T218, T26I, T252, upper winding of I8 and earth.
  • Reay 64through T644 completes the circuit of relay 63 in series with relay 28 which pulls up.
  • the loop to the automatic switchboard is completed through: conductor 6I', T633, T643, R55I, resistance, conductor 62.
  • relays 65 (Fig. 7) and 4G (Fig. 4) is completed: earth, winding of 65, T645, T631, wire 52', T214, T261, TI50, wire I of C03, T322, R4I I, winding of relay 48 and battery.
  • relay 65 On account of the high resistance of the winding of relay 48, relay 65 cannot be energized, but relay 48 pulls up.
  • the return impulse sent on the line conductors Li-Lz from the incoming exchange is receivedA at the outgoing exchange on relay I2 during the displacement of wipers b and d of the control switch from positions I8 to 2
  • Relay I2 completes through TI2I the circuit of the lower winding of relay I4 which pulls up and connects the line conductor-s Lr-Lg to relay I5 which receives the end of the impulse, and through TI5I maintains relay I4 attracted on its middle winding.
  • relay I4 pulls up
  • the circuit of relay I3 is completed through TI42, TI5I and earth.
  • Relav I3 pulls up after a moment.
  • the following circuit of relay I8 is completed: battery, lower winding of the relay I8, RIII, TI3I, TI42, TI5I and earth.
  • Relay I pulls up and opens at RIOI the outgoing circuit of position O of the control switch.
  • relay I releases and opens the circuit of relay 8 which fall-s back, as does relay I3.
  • Relay I I is energized in the following circuit in which the relay I IJ is maintained: battery, lower winding of Il, Tlil, T53 and earth.
  • the following circuit of relay I6 is completed: earth, winding of I6, TlI4, T69, tip of the plug of the cord pair, spring of key CA and its rest contact, spring I of key CE and its work contact, spring 2 of key CD and its work contact, spring Cn of the operators dial, signal lamp LI, resistance and battery, Relay I 6 is energized and lamp L1 lights up, indieating ,to the operator that she can begin todial the desired subscribers number. z.
  • Relay I6 whichhas pulled up,.connects theline conductors L1 and L2 to the terminals of thevoice frequencyv current generator Grez.
  • This voice frequency current is received on the equipment of Fig. 3, and transmitted to the equipments of Figs. 4 and 5 over the circuits previously traced, andis finally received in the detector device Dr causing the holding of relay 53.
  • the following circuit of relay 36 (Fig. 4) is completed: earth, winding of 36, wire 25', R5I I, T53I, resistance and battery. It will be seen that at the outgoing exchange owing to the fact that the dial contact-s Cn are inserted in the circuit of relay I6, said relay I6 will release for each interruption of contact C11., that is to say, for each dialling impulse.
  • relay 53 (Fig. 5) releases and completes the following circuit of relay 34: battery, resistance R53I, R5I3, wire 26', winding 34, T363 (the slow-acting relay 36 does not release during the reception of one train of irnpulses), RSSI and earth.
  • Relay 34 is energized and atT34I completes its holding circuit; At T342, it completes the circuit of relay 38 which pulls up.
  • relay 53 (Fig. 5) is energized and opens the circuit of relay 34 which falls back.
  • Relay 38 is maintained attracted in the circuit: battery, winding of 6, T382, T322', contact for the magnet Cmi and earth.
  • the following circuit of the upper winding of relay 31 is completed: battery, upper winding of 31, R312, T36I, T383, R342 and earth.
  • Relay 31 pullsrup. Through T31I, it completes its holding circuit on its lower winding. Through T312, it completes the following circuit for the energization of magnet Cmr: battery, electromagnet Cml, T312, T36I, T383, R342.
  • the magnet Cmi attracts its armature andV opens its contact which causes the release of 38 and, consequently, the opening at T383 of the circuit of magnet cm1 which releases its armature, thus causing the advance of the wipers of Coi by one step.
  • relay 38 short-circuits the lower winding of relay 31 which is thus rendered sufliciently slow not to release during the period of the reception of one train of impulses.
  • relay 3l releases after a moment
  • relay 36 is shortcircuited by T53l,:relay'53 being held attracted bythe voice .frequency :current emitted by the outgoing exchange; f
  • the condenser connected to the bank contact on which the. ⁇ wiped d. of 1G01 vhas stopped, will be charged in Athe circuit: battery, resistance, rst armatureof the condenser Ce, for example, wiper d, T353, T32I, T315, windings in parallel f -39 and earth.
  • TMI Through R43! it-opens the short-circuit around its lower winding, and through TMI connects through 4carri Cel magnet Cms of switch 'C02 to the earth through: T4l2, Rll-L-Rllll, T352, T32 l and earth.
  • relay43 completes the following impulse circuit: battery,.resistance, 'cam Co2, RMZ, T432, T4! l, T322, wiper I' of C03, wire I, T250, T267, T213, wipervB-oiiCoebank contact, wire 52', T531, T635, windingfof 135 and earth.
  • the wiperA ci Co2 willthus advance over the bank contacts to whichthe condensers Ci, C2 are connected.
  • the wiper arrives onV the previously charged condenser (C'e, for example), then Ythrough the wiper d, the condenser Ce, dis,- charged in relay 5, pulls up.
  • relay i5 opens -thecircuit lof magnet Cmz. .
  • the switch Co2 is stopped in the corre,- sponding position.
  • relay 35 8 relay 4l, whichfalls back.
  • VRelay ⁇ dl completes at R4H the circuit of relay 3! inseries vwith relay 63.
  • the 4circuit of relay t2 ⁇ is again completed, whereby afresh series of impulses is re-transmitted by relay 35.
  • the switchfCOi returns ⁇ to 'its normal posi ⁇ tio-n O.
  • relay 66 is energized through: earth, T634, lower winding of 61, winding of At6, and battery through the automatic switch.V
  • the ringing tone is transmitted through TBGI and T662 on wires 5I and 52' and, consequently, to the operator of the outgoing exchange.
  • relay 66 If the subscribers lineis busy, relay 66 is not energized, anda'busy tone is sent tothe operator of the outgoing exchange through R66I and R562.
  • relay 61 When the desired subscriber removes his receiver, relay 61 is energized and at T61I, closes the circuit of relay 68 which is energized after a moment.
  • the talking circuit is completed in the equipment of Fig. 1 through: conductor 5
  • relay 68 applies battery to wire 54 through T636 and the following circuit of relay 24 is completed: earth. RI 8
  • relay 24 completes the stepping circuit of the control switch through cam C3.
  • the circuit of magnet Cm3 is completed through T2I3, wiper d.
  • the control switch thus returns to normal position O.
  • relay I1 is energized by T2l2.
  • T2l2 At TI12 and TI1I. it connects the generator Gei to the line conductors Li-Lz.
  • a low frequency alternating current impulse is sent to the outgoing ex ⁇ hange.
  • This impulse is received in the equipment of the outgoing exchange (Fig. 2) by relay I2,'which pulls up and at TI2I, completes the circuit of the lower winding of relay I4 which is energized.
  • Relay I4 connects the line conductors at TI43 and TI4I to relay I5 which receives the end of the impulse.
  • Relay I5, through TI5I and TI42 completes the circuit of relay I3 which pulls up after a moment.
  • the following circuit of the upper winding of relay IG is completed: battery, upper winding of I9, TIII, TI3I, TIM; TI5I and earth.
  • the two windings of I6 are so arranged that their fluxes are opposed.
  • the relay I6 releases its armature.
  • Relay II is maintained attracted on its upper winding through earth at TI I I and the circuit previously indicated.
  • relay I5 falls'back causing the release of relay II.
  • Relay IIJ of which the flux should be reversed, falls back and remains down.
  • relay II opens the circuit of relay 9 whichfalls back, opening at T92 the short-circuit of the upper winding of relay '5, which causes the release of relay I of the'cord.
  • the lamp L2 stops flickering and the operator is thus advised that the desired subscribed has replied;v She can get in touch with the subscriber, warn him that a communication is about to be established and complete the connection to the calling .subscriber by the second plug of her cord in the usual way.
  • the control switch advances one 'step and passes to position I; the circuit of its magnetis then completed through cam C1 and RTI by wiper e ofthe control switch in positions I to I6, and wiper f in positions II to 2I.
  • the control switch will thus perform one complete rotation.
  • the line conductors L1 and L2 are connectedito the low frequency generator Gel and a release impulse is sent to the incoming exchange.
  • the profile ofthe cam C1 is such that the control switch will be much slower than when it is actuated by cam C2.
  • the result is that the period ⁇ of the release impulse will be far greater than that of a supervisory'. impulse so as to insure the release, even if a supervisory impulse were being866om the incoming exchange to the outside exchange.
  • the release impulse is received on the'relay I8 (Fig. 3) which at TIBI, completes the circuit of the lower winding of I9 which pulls up.
  • Relay I9 applies earth at TI93 to the upper winding of relay 22. The ux of this winding being opposed to theY uX of the lower winding, the armature of relay 22 falls back.
  • opens at T2I2 the holding circuit of relay 2G which falls back causing the release of the equipment of Fig. 7, or of the callequipment (Fig'. 6) of the operator.
  • Relay 24 is energized in the circuit: battery, wiper c of the control switch in position O, T2I5, winding of 9, R253, T262 and either T21I and earth on wiper S,- or R21I and earth on wire S', Through TMI, relay 24 completes the circuit of magnet Cm3 of the control switch.
  • the control switch advances to position I I, and during the passage of the wiper a. in the positions I to 1, the circuit of relay I1 is closed and the generator G'e1 is connected to the line conductors. A low frequency transmitting current impulse is sent to the outgoing exchange.
  • relay I2 (Fig. 2) and causes the pulling up of relays I2, I4, I5 and I3.
  • Relay I2' is energized on its lower winding through RIII, TI3I, TI42, TI5I and earth.
  • a nal low frequency impulse is sent by the inal equipment of the cord pair through: generator Gei, RI I5, TIUZ, R58,A tip of the plug, spring of CA and its rest contact, spring d of CE and its rest contact, relay 2, spring I of CE and its 111 rest contact, spring of CA and its restv Contact, sleeve of the plug, R65, TEM, RI'IB and generator
  • the relay 2 is energized and' through T21. completes the circuit of 3, which is energized'.
  • circuit of the end lamp L is completed: earth, T3I, RII, lamp L2 and battery. 'The lamp L2 is'lighted indicating to the operator that the communication is finished.
  • relay II sticks and at R
  • Thevoice frequency impulse isvreceived, as has been. explained, on relay 53k causing the holdingl of relay 36. At the end of the reception of the impulse, relay 53 fallsA back and' completes the above travel holdingv circuit of relay 34. which is energized. At T342, relay'34 completes the circuit of relay 38 whichpulls up, and at T382fcloses its holdingcircuit through T322', contact of magnet Cmi and earth..
  • relay 36 Shortly after relay 341 has pulledl up, relay 36 being short-circuited atI T343, falls back. Earth is applied to wiper V of switch Cos through: earth, R342, T383, R361, RI', wiper V.
  • Relay 26 remains attracted, but relay. 23, of which the circuit. is opened at T212, falls back, opening at T283 the circuit of. relay 25, which falls back and causes the release of the register.
  • relay 58 (Fig; 6) is completed: battery, winding ofl 58; R5'II, Wire C', T263, R212 andearth.
  • Relay 58' is energizedandcompletes the circuit of the call lamp L2.
  • relay 58 connects the inter-urban ringing tone generator to the line conductors and thus to the outgoing operator.
  • the outgoing operator can now,y communicate with the incoming operator.
  • the incoming operator by keying causes the transmission of a calling current on the conductors A and B.
  • This current causes the pulling up of relay 54 which, at TMI, applies earth to wire D', energizing the middle winding of the relay I9 and causing it.y to pull up.
  • the line conductors L1 and L2 are cut off at RI92 andRI 94, and the calling current is not sent to the equipment ofthe outgoing ex. change so as to prevent false operations.
  • a plurality of .ex- Y changes, subscribers lines terminating at' said exchanges, operatorsv at the exchanges, trunks interconnecting said exchanges, automatic switches at some of said exchanges numerically operable to establish connections with lines, an impulse device at the calling exchange operators position, a source of voice frequency current at the calling exchange, ⁇ means controlled ⁇ by the impulse device for producingl interruptions in said voice frequency current in accordance with numericall designation of the called line, means responsive to said interruptions for controlling the automaticswitches at the called exchange to select the called'line, and means at the called exchange for measuring the length of said interruptions, and means for permitting an impulsev to become eiTective only if the length of the interruption produced by the impulse device does changes, operators positions at each exchange, automatic switches at some of said exchanges.
  • switching means at the called exchange for connecting a predetermined operator with the first connection, andmeansoperable upon the establishmenty of the first connection for sending a predetermined signal; from the calling exchange for operating said switching means.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Telephonic Communication Services (AREA)
US507469A 1939-02-24 1943-10-23 Multioffice telephone system Expired - Lifetime US2431321A (en)

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FR50457T 1939-02-24

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US507470A Expired - Lifetime US2468057A (en) 1939-02-24 1943-10-23 Multioffice telephone system

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FR (3) FR854039A (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2603717A (en) * 1947-07-10 1952-07-15 Automatic Elect Lab Carrier telephone system
US2744963A (en) * 1953-12-14 1956-05-08 Gen Dynamics Corp Multi-office telephone system
US2797262A (en) * 1954-04-29 1957-06-25 Itt Automatic telephone systems

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR854039A (fr) * 1939-02-24 1940-04-03 Cie Telephones Thomson Houston Perfectionnements aux systèmes téléphoniques

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1613246A (en) * 1922-11-15 1927-01-04 Western Electric Co Telephone-exchange system
US1820682A (en) * 1929-07-17 1931-08-25 Int Standard Electric Corp Telephone system
US2141372A (en) * 1935-10-16 1938-12-27 Bell Telephone Labor Inc Telephone system
US2155176A (en) * 1936-11-07 1939-04-18 Associated Electric Lab Inc Telephone system

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR854039A (fr) * 1939-02-24 1940-04-03 Cie Telephones Thomson Houston Perfectionnements aux systèmes téléphoniques

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1613246A (en) * 1922-11-15 1927-01-04 Western Electric Co Telephone-exchange system
US1820682A (en) * 1929-07-17 1931-08-25 Int Standard Electric Corp Telephone system
US2141372A (en) * 1935-10-16 1938-12-27 Bell Telephone Labor Inc Telephone system
US2155176A (en) * 1936-11-07 1939-04-18 Associated Electric Lab Inc Telephone system

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2603717A (en) * 1947-07-10 1952-07-15 Automatic Elect Lab Carrier telephone system
US2744963A (en) * 1953-12-14 1956-05-08 Gen Dynamics Corp Multi-office telephone system
US2797262A (en) * 1954-04-29 1957-06-25 Itt Automatic telephone systems

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Publication number Publication date
FR854039A (fr) 1940-04-03
US2468057A (en) 1949-04-26
FR50906E (fr) 1941-05-10
FR50457E (fr) 1940-11-14

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