US2232189A - Telephone system - Google Patents

Telephone system Download PDF

Info

Publication number
US2232189A
US2232189A US134500A US13450037A US2232189A US 2232189 A US2232189 A US 2232189A US 134500 A US134500 A US 134500A US 13450037 A US13450037 A US 13450037A US 2232189 A US2232189 A US 2232189A
Authority
US
United States
Prior art keywords
relay
armature
over
lead
earth
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US134500A
Other languages
English (en)
Inventor
Taylor Reginald
Baker George Thomas
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Associated Telephone and Telegraph Co
Original Assignee
Associated Telephone and Telegraph Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Associated Telephone and Telegraph Co filed Critical Associated Telephone and Telegraph Co
Application granted granted Critical
Publication of US2232189A publication Critical patent/US2232189A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/58—Arrangements providing connection between main exchange and sub-exchange or satellite

Definitions

  • the present invention relates to telephone systems and is more particularly concerned with systems having a plurality of interconnected exchanges such as for instance a main exchange associated with a number of satellite exchanges.
  • the improved arrangements can be simply adapted for use in satellite exchange networks of varying complexity and thus produce substantial economies in manufacture and generally simplify the work of exchange maintenance.
  • the discriminating portion and the selector portion of the arrangement are formed as independent units, and the selector portion is made capable of functioning either as a first code selector for use in a register controller system incorporating zone metering or in a multi-exchange system such as for example a satellite exchange system with zone metering and route discrimination under control of a separate discriminating unit accessible in common to a plurality of selector portions.
  • the zone metering equipment of this unit is distinct from the route discrimination equipment so that the two functions may be determined after different numbers of digits have been received.
  • Figs. 1, 2 and 3 show the circuits of a selector and an associated hunter switch which are intended to function in two capacities.
  • they may be employed as a first code selector and an A digit selector hunter in a register controller system with provision for zone metering facilities which may be either level controlled or controlled from the register controller.
  • the selector and hunter may be used in a manner to be described in conjunction with the sending unit and discriminating unit shown in Figs. 4, 5 and 6, and '7, 8 and 9 respectively to form a discriminating arrangement with control of metering from the discriminating unit.
  • the outgoing junctions to the main exchange are connected to the first level of the selector, this level being reserved for this purpose; no separate junction hunter switch is therefore required.
  • Figs. 4, 5 and 6 show the circuits of a sending unit which is accessible. from the selector of Figs. 1, 2 and 3 over the hunter switch and includes a mechanical impulse regenerating device of the type disclosed in J. W. McClew and C. R. Woodlands application No. 79,830, filed th May 1936, which is adapted to receive and store trains of impulses.
  • the received impulse trains are sent out in regenerated form to actuate either the satellite or parent exchange selectors in accordance with the route discrimination determined in the discriminating unit.
  • Facilities are also provided to absorb certain digits in response to signals from the discriminator by arranging to short-circuit the pulsingout leads until such time as these unwanted digits have been sent out by the impulse regenerator.
  • Figs. 7, 8 and 9 show the circuits of a discriminating unit which is directly associated, with the sending unit and comprises essentially a 3 uniselector which is set by the calling subscribers dialled impulses in parallel with the impulse regenerator.
  • the uniselector bank contacts are marked between successive impulse trains and according to the particular cross-connection employed it is possible in response to the dialling of one or more routing digits to effect the determination of the appropriate meter fee and of the proper route for the call.
  • the two-directional switch employed in the selector is assumed to be of the type disclosed in R. N. Saxbys Patent No. 2,028,639, granted 21st January 1936, having a so-called rectangular motion while the unidirectional switches employed are of the well-known reverse drive type.
  • any connections which are alterable to suit the conditions to be met are inserted in chain dotted form, the connections referred to being those from the CO and DA terminals in the discriminating unit to the CO and DA terminals in the sending unit and also those from the banks of the D switch to various terminals in the discriminating unit.
  • relay L operates over the incoming line loop in series with the iron hydrogen current limiting device BRA and at armature ll operates relay A and I in series to earth over resistance YA, (relay D being nonoperative in this condition due to rectifier MRE being in a conductive direction) and at armature 12 operates relay B.
  • a circuit is thereby closed for the lower winding of relay C over armature bI and a2, while relay BB operates over armature b2.
  • Relay BB in operating thereupon at armature bbl applies guarding potential to the incoming P conductor while relay C in operating at armature c3 completes a self-- interrupted driving circuit for the sending unit hunter switch magnet SUHM from earth which is connected to a common lead II by way of equipment which is arranged to give a delayed alarm in case of failure to release, armatures k2 and m4, wiper H in the home position, armatures c3 and M3, interrupter contacts suhm, magnet SUHM to battery.
  • the switch rotates in search of a disengaged'sending unit which is marked by battery potential on the associated P contact.
  • a tree outlet relay K operates quickly overt-earth, resistance YD, armatures al and m2, windings of relay Kin series, P wiper and P lead to battery over armatures 006 and resistance YE in parallel with the left-hand winding of relay IA in the idle sending unit.
  • Relay K upon operating at armature k2 disconnects the magnet driving circuit to arrest the motion of the switch and at armature kl extends a guarding and holding potential by way of its low resistance lower winding; at the same time the short circuit is removed from relay KR which now operates from earth over resistance YD, winding of relay KR, contacts m3, c5, resistance YB to battery.
  • the upper winding of relay K is energised in an opposing direction to its lower win-ding in order to enable it to release in the case of a dual connection.
  • Relay KR upon operating, at armatures kr3, kr4, kr5, krfi and kr'l switches the control leads through to the sending unit, whereupon earth is extended from armatures Z2 and krl over the PU lead to hold re'lay IA in the sending unit, this relay having been initially operated over its lefthand winding in series with relay K.
  • a loop by way of armatures Im2 and id in the sending unit is returned over the negative and positive conductors to maintain relay A operated in the selector.
  • Relay IA in operating at armature I (ll operates relay IB in series with the impulse regenerator receiving magnet MR, the resistance YG serving to prevent false impulses to the magnet MR when all three springs of relay IA are in contact.
  • Relay IB in operating at armature IbI completes a locking circuit for itself, at ar-.
  • the idle marking battery connected to the P lead initially comprises the left-hand winding of relay IA and resistance YE in parallel and on operation of relay LR consists.
  • relay IA The subscriber now dials the first digit and relay L in the selector responds and at armature 12 repeats the impulses over the PU lead to relay IA in the sending unit.
  • relay IA releases a circuit is completed to energise the impulse regenerator receiving magnet MR as follows:-earth, armatures IbI, Ial and e05, magnet MR to battery while at the same time relay IC is energised in parallel.
  • a circuit is also completed to energise the magnet DM of the switch in the discriminating unit as follows:earth, key contacts K132, armatures I b5 and Ia2, IPU lead, armature zm2, magnet DM to battery.
  • the digit is mechanically stored in the impulse regenerator in a manner to be described, while the switch D in the discriminating unit is advanced to a position corresponding to the digit dialled.
  • relay IB is intermittently short-circuited by the resting armature Ial but this relay will remain held due to the slugging effect of the short-circuited winding, while relay IC will hold during the impulse train due to its slug. It will be readily understood that neither the magnet MR nor relay IC will either operate or hold in series with relay B and moreover the inductance of the relay IB is such that it has no appreciable effect on the magnet performance.
  • the mechanical impulse generator hereafter termed regenerator comprises essentially a receiving ratchet wheel X which is rotated step-by-step under control of the receiving magnet MR and which is arranged on one side of a fixed disc Z carrying round its periphery a row of 40 pins.
  • the rotation of the receiving disc stores up energy in a clock spring to drive the sending disc Y and thus actuate the impulse springs IMP and send out regenerated impulses of the correct character and rate.
  • the armature of a so-called marking magnet is resting on a pin in the disc Z which it has pushed forward to restrain the sending disc Y.
  • the sending disc Y is at present restrained by the pin which was displaced at the end of the previous call.
  • the off normal springs MN close and at the end of the digit when relay lC releases relay ON operates over contacts MNI and armature lcl and locks to the operated off normal contacts at armature onl and at armature on2 disconnects the dial tone.
  • the D switch in the discriminating unit Figs. '7, 8 and 9 has also been stepped by the trains of impulses and in a manner to be de scribed more fully later determines whether the call is to be routed locally or by way of an outgoing junction to the parent exchange, this discrimination taking place after the first, second, or third digit.
  • relay JD in operating at armaturea'dz operates relay LD and at armature 7'd3 operates relay IP whilst at armature :id4 it opens the hold-- ing loop for relay A in the selector over the outgoing negativeand positive conductors.
  • Relay LD in operating at armature ldl disconnects relay LR and hence during the release time of this relay the outgoing loop to relay A in the selector will be opened, but on release, armature 11-3 again extends a loop by way of the impulse springs IMP and armature lm2 to re-operate relay A.
  • relay A in releasing at armature a2 completes a circuit from earth by way of armatures bl, a2 and cl to energise the vertical magnet VM in series with the low resistance upper winding of relay C and accordingly the selector wipers are raised to the first level on which are wired the outgoing junctions to the main exchange whereupon the on normal contacts N are mechanically operated and at contacts NI extend earth from armature 02 to operate relays HB and HA over their middle windings.
  • relay A On re-operation of relay A, the vertical magnet energising circuit is disconnected while relay C now releases after a short interval due to its slug since its preenergising circuit over its lower winding is disconnected at ofi normal contacts N2.
  • Relay C in releasing at armature c2 completes an energising circuit for the rotary magnet RM from earth, armatures bb3, ml, dbl, hb3, ha3, rotary magnet interrupter contacts rm, ofi normal contacts Nl, armature c2, magnet RM to battery and the wipers will therefore be advanced into engagement with the first set of the contacts in the level selected whereupon the rotary all normal springs NR will be mechanically operated while the magnet interrupter contacts rm will also be opened.
  • a circuit is now completed from earth, armature bl, rotary oif normal contacts NR2 and armature ha to operate relay BA and thereupon at armatures ba2, ba4, ha I, hb-l and hb5 the negative and positive pulsing out leads from the sending unit are switched through to the lower set of negative and positive wipers whereupon the loop extended from the sending unit now operates the A and B relays in the main exchange incoming switch in preparation for the reception of regenerated pulses.
  • Armature bal disconnects the right-hand winding of relay HB from the testing wiper Pl and this relay now holds as follows: earth, armatures bb3, ml, dbl, hb3 and M13 to battery over its left hand winding.
  • relay HB releases to open the magnet driving circuit at armature hb3 while the outlet selected is immediately guarded over this wiper from earth, armatures hbG, D126 and m8.
  • Relay BA will be operated as previously described and extends the loop from the sending unit over the upper set of wipers through to the junction.
  • both test relays HA and HB 'restore whereupon relay BA is energised as above and relay HA is re-operated on its left-hand winding from earth, armatures bb3, ml, dbl and hb3 and rotary oil normal contacts NRI.
  • the pulsing out loop is therefore switched through to the upper set of wipers and it will be seen that priority is always given to the upper set of wipers in these circumstances.
  • relay LR on releasing at armature lr completes a circuit to operate relay P from earth, regenerator oil normal contacts MNI, fixed disc Z which is in contact with a pin left projecting from a previous call, the reset pin in the disc Y which bears against the former pin, sending magnet interrupter contacts ms, armature lr5, winding of relay P to battery.
  • Relay P in operating at armature p2 energizes the control switch magnet CNM, at armature p3 disconnects relay IP, at armature p4 prepares an energizing circuit for the regenerator sending magnet MS, and at armature p5 completes a locking circuit for itself.
  • the release time of relay IP is arranged to be of the order of 600 milli-seconds which period allows the selector ample time to hunt for a free outlet and on release of this relay the regenerator sending magnet MS is energised whereupon relay P now releases since its holding circuit is disconnected at both the interrupter contacts cnm and ms, associated with the magnets CNM and MS respectively.
  • Relay P in releasing re-operates relay IP at armature 123 in preparation for provlding the next interdigital pause while at armatures p2 and p4 the magnets CNM and MS are de-energised whereupon the CN wipers are advanced to position 2.
  • the reset pin is moved to restore to its normal position the movable pin in the disc Z against which it has been resting and the sending disc Y is now free and rotates due to the wound clock-spring and operates the impulse springs IMP to send out impulses over the outgoing negative and positive leads, the first train of pulses sent out serving to set the main exchange selector.
  • the sending disc rotates until it encounters the pin displaced at the end of the first dialled digit when relay P will be energised as before and will again open the circuit of relay IP and the sending out of the second digit will be held up until relay IP fully releases. This process is repeated for each digit stored and it will be appreciated that the regenerator is capable of receiving and transmitting impulse trains simultaneously. It will be seen that for this type of call the dialled digits are merely regenerated and retransmitted.
  • the necessary multi-fee registration is set up in accordance with the digits dialled from the discriminating unit over the metering leads M2, M3 and M4 on to relays IMA and IMB and is retransmitted to the selector.
  • relay IMB only is operated
  • relay MB in the selector will be operated on its right-hand winding in series with the magnet SUHM over the MB lead and connects up to the double fee metering lead at armature mb3 whilst if relay l MA only is operated relay MA in the selector will be oper- I ated in a circuit over earth, resistance YF (Fig.
  • relay MA in operating at armature ma2 connects up the triple fee metering lead. I! both relays MA and MB are operated the quadruple metering lead will be connected up, whilst if neither is operated the single fee lead is connected up.
  • the wanted subscriber After all switches in the train have been set the wanted subscriber, if free, will be signalled in a normal manner by ringing current transmitted from the final selector in the train and when he answers, the current will be reversed over the speaking conductors so that rectifier MRE bridged across relay D in the selector will no longer be in a conductive direction thus allowing this relay to operate.
  • armature dl it connects up the left-hand winding of relay DA to the S pulse cam of the meter delay set and at armature d2 prepares a locking circuit for this relay over its middle winding.
  • the delay set comprises so-called S and Z pulse cams arranged to supply battery pulses with a definite time relation to two corresponding leads.
  • relay DA On transmission of the next S pulse, relay DA will be operated and at armature da5 prepares a circuit for relay DB which is operated after the appropriate time interval from the Z pulse in series with the righthand winding of relay DA.
  • Relay DA remains locked over its middle winding in series with resistance YC until relay DB operates on the Z pulse when both the initial energising circuit and the locking circuit for relay DA are opened but this relay remains held on its right-hand winding in series with the lower winding of relay DB for the duration of the Z pulse.
  • relay RG During the application of the Z pulse relay RG is connected by way of armatures d412, dal and the armatures of relays MA and MB to the selected metering lead and in accordance with the setting of these two latter relays, relay RG will be operated a predetermined number of times and at armature rgl will repeat these pulses over the incoming P conductor in the form of booster battery pulses to actuate the subscriber's meter.
  • relay DA restores to prevent any further operation of the metering relay RG while relay DB remains operated from earth via armatures bb3 and ml on its upper winding in series with the left-hand winding of either relay HA or relay HB since the upper winding is no longer short-circuited at armature dbl.
  • the equipment is arrangedto absorb any unwanted digits. If, for example, it is arranged to absorb the first two digits, earth will be extended over the LD lead from the discriminating unit at the end of the third dialled digit, thus operating relay LD in the sending unit.
  • This relay in operating at armature Zdl disconnects relay LR and also looks via this armature to the earthed holding lead.
  • no preliminary impulse is given to the A relay of the selector since relay JD is normal and maintains a loop across the outgoing negative and positive contacts by way of armatures HM and 7d4.
  • relay JD When relay P subsequently operates in a normal manner after the sending of this last absorbed digit, relay JD will be operated over its left-hand winding from-earth over armatures ipl and p6 and at armature :idl locks to the holding lead, at armature i113 disconnectsthe operating circuit of relay IP and at armature jdd removes the short circuit from across the regenerator impulse springs 1MP.
  • thesending out is re-commenced and from this point it takes place in the manner described for a junction call except that the first selector is stepped to some level other than level one and therefore the main exchange equipment is not used.
  • an area has the following numbering scheme: routed to main exchange over level I (20006999, 8000-42999); routed to manual board over level 0 (0); routed to adjacent automatic exchange over level 3 (73000 to 73999); routed locally over levels -8 (71500-71899); routed locally over level 2 (72000-72599).
  • the main exchange number 8456 is dialled.
  • the first digit dialled will step the switch D to contact 9 (the home position being contact I) and at the end of this digit relay IC in the sending unit releases and at armature I02 extends the earthed holding lead over the C lead to wiper D'I. Since it is required to route the call through to the parent exchange, contact 9 on the D1 bank will be connected to ta m and thence by way of armature Ida-5 and a cross connection between tags it and a on to the JD lead.
  • relay JD in the sending unit will be operated at the end of the first digit and will cause the digit stored in the regenerator to be sent out in the manner hereinbefore described.
  • the remaining digits in the number dialled further step the switch D for the purpose of determining the meter fee in the manner to be described later.
  • wiper D1 On reception of the first digit 7, wiper D1 will be stepped to contact I which is strapped to terminal J thereby operating relay IDA, which in operating at armature IdaI locks to the earthed lead HL while at armature Idal it disconnects the earth from the terminal DAI.
  • the second digit 1 steps switch D further to contact 9 which is strapped to terminal m thereby operating relay IDB which locks and removes the earth from terminal DA2 at armature IdbS.
  • the switch On dialling the third digit 8 the switch is advanced to contact 17 which is strapped to terminal 9 whereupon earth will be extended at the end of this digit on to the LD lead byway of the cross-connection and armature ldb2.
  • Relay LD in operating initiates the sending out of the regenerator as previously described for a local call.
  • the following digits 22 further step the D switch in case the meter fee cannot be determined until the 4th or 5th digit.
  • tags am and the associated contact combinations of relays lDA and IDB enable any num-, bering scheme to be catered for with discrimination on first, second or third digits.
  • the discrimination may be deferred until the 4th and 5th digits, in which case terminals DA4 and DA5 in the sending unit would be brought into use. Since only one bank of the D switch, that is the D1 bank, is used to provide the route discrimination, it is necessary to provide the above arrangement to preclude any possibility of a call being incorrectly routed, where for example, the D switch is stepped to the same position in response to either main exchange or local or other routing digits.
  • digit 8 may be dialled as a first digit, at the end of which earth is extended over the D1 wiper in position 9 by way of tags m, k and a on to the JD lead whereupon relay JD will be operated; at the same time the dialling of the first two digits 71 of a local exchange number would also step the D switch to contact 9.
  • relay IDA is operated at the end of the first digit in the manner previously described, and at armature Idai thereupon changes over the link between contact 9 and the JD lead to relay IDB in preparation for the second digit 1.
  • the switch D is also used to determine theappropriatemeter fee and this may not be possible until as many as five routing digits have been dialled according to the complexity of the network.
  • the D switch is further used for the important function of barring access to various routes under certain conditions. Assuming now that the dialling of two digits 73 will route the call into a particular meter fee zone, the switch D will he stepped to position 8 after the first digit and during the inter-digital pause earth will be extended 'over the C lead by way of resting armatures sd2, s02, sb! and sa! and thence via a strapping connection from contact 8 to terminal SA.
  • Relay SA is thereupon operated and locks to the BL lead and at armature sai switches over the C lead on to the D2 wiper in preparation for the next digit. 0n reception of the next digit the switch is further stepped on to contact II while at the end of this digit earth will be extended by way of a strapping from contact II on the D2 bank to the appropriate meter fee terminal I-l or I (CCB barred), the use of the latter terminal being explained later.
  • connection will be taken from contact II on the D2 bank to terminal 2 and thence by way of armature r33 (relay RS being normally operated on a call from a regular subscriber) on to'the M2 lead and thence to the sending unit whereupon relay IMB is operated and this relay in turn operates relay MB in the first selector which connects up the double fee metering lead.
  • Relay IMA or IMB in operating extends an earth over the ZM lead into the discriminating unit whereupon relay ZM is operated over its right-hand winding and at armature zm3 locks to the earthed holding lead HL.
  • Armature zmI extends an earth by way of its left-hand low resistance winding to self-drive the D switch to the home position, since the remaining digits to be dialled need not actuate this switch. Furthermore on the subsequent release of the common equipment when all digits have been dialled it can be made more quickly available for further common use since there is no necessity to wait for the D switch to home. In the case of single fee calls relays IMA and IMB would not be operated, relay ZM being operated direct from the meter fee terminal I.
  • Relays CA, CB and CC provide cut-oil. conditions for varying numbering schemes in order that the common equipment can be released immediately a suflicient number of digits have been dialled.
  • relays CA to CC will be unaffected and an earth would thus be extended over resting armatures ccB, chi; and ca6 on to terminal COI and thence via a cross connection to terminal 005 in the sending unit. Since the switch CN in the sending unit is advanced one step before each digit is sent out, wiper CN4 will be advanced to position 6 thereby making connection with terminal CO5 just prior to transmission of the 5th digit.
  • This relay releases after a short interval when relay COwill be operated from the earth encountered by the wiper CN4 and at armature 002 extends an earth on to the common conductor I8 extending to delayed alarm equipment which gives an alarm in case the apparatus fails to restore to normal causing it to release and at armature krl, krl to disconnect the control leads through to the sending unit and at armatures krfl and lcrI to connect the incoming speaking leads through to the negative and positive wipers.
  • armature krl a homing circuit is completed for sending unit hunter switch from earth on common lead I'I.
  • Relay IA in the sending unit now releases and in turn releases relay IB which removes earth from the holding lead HL thus releasing all relays held thereunto whilst the switch CN is homed to one of its two home positions.
  • Relay CO is maintained operated during the homing of this switch to guard the common equipment until all the apparatus therein has restored to normal.
  • the meter discrimination is not wired direct from one of the banks D2 to D6 to the required unit tag but via a changeover contact of relay CA so that this relay operates before passing the signal to relays IMA, IMB or ZM.
  • C0 tag 2 is wired to terminal 4 associated with the CN bank to give a cut-oil after four digits have been sent.
  • Relays CB and CC are used for example to cater for single digit and six digit numbers respectively while if more than four different kinds of numbers exist in the same network additional relays are provided.
  • Suflicient CO terminals are connected to the CNl bank to cater for a cut-01f after the sending out of up to nine digits.
  • relay RS On calls from regular subscribers, as soon as relay LR is operated in the sending unit, relay RS is operated on its right-hand winding over the RS lead, armatures 1T3, jdl and Im2, negative lead, winding of relay A in the selector to battery. On coin box calls however an earth is extended from the line finder over the D lead to the selector and serves to shunt relay RS and prevent its operation. It will therefore .be seen that the meter fee terminals I (CCB barred), 2, 3 and 4 are extended to the spare code lead SC thus operating relay IM at some point of the call.
  • This relay in operating, locks at armature ImI to the holding lead, disconnects the loop over the outgoing negative and positive conductors at armature Im2, prepares a circuit for earthing the forced release lead FR at armature Im3 and earthsthe ZM lead to home the D switch at armature Im4.
  • the disconnection of the loop will prevent any further impulses sent out from the regenerator from being effective whilst if a junction call is being set up the distant equipment will be released.
  • After all digits have been sent out from the regenerator relay ON will be released and on release of relay IP after its slow release period an earth will be extended on to the FR lead by way of armatures ipl, 011.4 and Im3.
  • Relay M in the selector is now operated on its right-hand winding and locks up over its lefthand winding at armature ml and also disconnects the holding circuit of relay DB and either relay HA or relay HB whichever is operated at the same armature, releases relay KR at armature m3, opens the homing circuit of the hunter switch SUH at armature m4, earths common lead I2 extending to supervisory equipment at armature m5, connects flicker earth over common lead I0 at armature m6 to the lamp LP which is connected to battery by way of delayed alarm equipment connected to common conductor I I so that in case relay M is maintained operated for longer than a predetermined period an alarm will be given while the lamp flashing will indicate the switch involved to the maintenance ofiicer.
  • Armature m'l connects up the NU tone transformer over common lead l3 to the upper winding of relay I whence the tone is returned to the calling subscriber in a balanced circuit while armature m8 prevents an earth being extended on to the P lead when relay HB releases.
  • relay IM will be operated as above and in case the regenerator has not started-sending out due to the fact that the D switch in the discriminator has not received sufllcient digits to determine the type of call the FR lead will be earthed over resting armature M2 and armature I213.
  • the sending unit is provided with a so-called meter and time pulse disconnection key KD which allows a maintenance oflicer to efiect a continued routine on the unit without any operation of the tramc recorder and without the time pulse mechanism coming into efiect.
  • a busying key KB is also provided which is operated when it is desired to busy-out the unit; on operation the supervisory lamp ILP is lit over 1 contacts KB3, the idle marking battery is disconnected from the incoming P conductor contacts KBl, the earth for the common lead is disconnected at contacts K32 and the operating earth for relay IB is disconnected at contacts KBI.
  • relay CO will be operated to guard the equipment during the homing of the switch.
  • Relay L in the selector will then release but the battery connection will be extended over the positive lead, lower winding of relay I, armatures ll, do and d113, rectifiers MBA and MRB in a conductive direction and armatures dbl and ill to earth.
  • relay I is held operated and at armature il holds relay B and thus prevents release of the connection.
  • Relay RG is non-operative in this condition as it is shunted by the rectifiers.
  • relay L releases and opens the circuit of relay B.
  • relay B releases and opens the circuit of relay BA which releases after a further short period.
  • Armature ba3 thereupon removes earth from the incoming P conductor and also releases relay BB whereupon armature bbl reconnects earth to the P lead by way of the operated off normal contacts M3.
  • Relay BB also at armature bb3 releases relay DB and either relay HA or relay HB, these relays being previously held in series.
  • a self-interrupted driving circuit is completed for the magnet RM from the earthed lead I1 and accordingly the wipers are rotated clear of the banks after which they fall and rotate under the banks under spring tension back to their normal positions where the off normal contacts NI open and disconnect the homing circuit.
  • the rotary magnet is mechanically prevented from opening its interrupter contacts during the release movement so that there isv no tendency for it to chatter.
  • test jack springs T are provided, their use being readily ascertained from the drawings. Furthermore each magnet is Should he require a trunk call which made from a portion of the received trains of impulses, means normally efiective during the regeneration of said trains of impulses to insert an interdigital pause between successive regenerated trains of impulses, and means controlling said last means to substantially prevent the insertion of an interdigital pause between successive trains of impulses which are regenerated but not re-transmitted.
  • a controller for operating said switches, means for seizing said controller and transmitting thereto a code of impulses to direct the extension of a connection, a first register in said controller operated by said impulses to register the whole of said code, a second register in said controller also operated by said impulses to register the whole of said code, means in said controller controlled by said first register for determining the path over which said connection is to be extended, means for operating the switches in accordance with said determination to extend the connection over said path, and means in said controller controlled by said second register independently of said first register and of the connection extended under control of said first register to assess an arbitrary value to said extended connection, said value depending upon part of the code registered by said second register.
  • a register controller for operating said switches, means for seizing said register controller and for transmitting thereto a plurality of digits to direct the extension of a connection, means in said register controller for registering at least part of said digits transmitted to said register controller and for determining from said part thereof which of the digits transmitted to said register controller shall be retransmitted, other means in said register controller for registering all of said digits transmitted to said register controller and for retransmitting certain thereof in accordance with said determination made by said last means, thereby to operate said switches to extend said connection, and still other means in said register controller for registering at least part of said digits transmitted to said register controller and, in accordance with said part, assessing an arbitrary value to the connection extended by said switches under control of said retransmitted digits.
  • a register controller for operating said switches, means for seizing said register controller and for transmitting thereto a plurality of trains of impulses to direct the extension of a connection, means in said register controller for receiving said trains of impulses and for subsequently retransmitting certain thereof to operate said switches to extend the connection, a discriminating switch in said register controller having a plurality of wipers operated by all of said received trains of impulses, a circuit completed over one wiper of said discriminating switch when a certain number of said trains of impulses have been received, means controlled over said circuit for determining which 01' the received trains of impulses shall be retransmitted and for controlling said last means to retransmit only those trains of impulses, another circuit completed over a different wiper of said discriminating switch when a certain number of said trains of impulses have been-received, and means controlled over said last circuit for assessing an arbitrary value to said connection extended by said automatic switches under control of said retransmitted trains of impulses,
  • a register controller for operating said switches, means for seizing said register controller and for transmitting thereto a plurality of trains of impulses to direct the extension of a connection, means in said register controller for receiving and subsequently regenerating all of said trains of impulses, other means in said register controller for receiving said trains of impulses and for determining from certain thereof which, if any, of the regenerated trains of impulses shall be absorbed in said register controller, means for counting the regenerated trains of impulses, and means controlled conjointly by said last two means for at times preventing one or more of the regenerated trains of impulses from being transmitted to operate said switches.
  • control equipment means for seizing said equipment and transmitting thereto trains of impulses each having a cretain digital value
  • means in said equipment responsive to said trains of impulses and effective subsequently to regenerate all thereof
  • separate means in said equipment also responsive to said trains of impulses and effective, upon said regeneration thereof, to at times suppress certain of the regenerated trains of impulses depending upon the digital values of one or more of the received trains of impulses, and means for transmitting only the unsuppressed regenerated trains of impulses to operate the automatic switches to extend a connection.
  • automatic switches means for seizing one of said switches and transmitting signals thereto corresponding to the digits of a called station number, common control equipment, means for associating said equipment with a switch when seized, means 10 in said equipment for registering the signals for each received digit, separate means in the equipment also operated responsive to the received signals and eiiective in accordance therewith to at times suppress certain of the signals registered by said registering means, and means controlled by said registering means to retransmit only the registered signals not suppressed by said last means.

Landscapes

  • Physics & Mathematics (AREA)
  • Astronomy & Astrophysics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Monitoring And Testing Of Exchanges (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Meter Arrangements (AREA)
US134500A 1936-04-03 1937-04-02 Telephone system Expired - Lifetime US2232189A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB9973/36A GB473003A (en) 1936-04-03 1936-04-03 Improvements in telephone systems

Publications (1)

Publication Number Publication Date
US2232189A true US2232189A (en) 1941-02-18

Family

ID=9882179

Family Applications (1)

Application Number Title Priority Date Filing Date
US134500A Expired - Lifetime US2232189A (en) 1936-04-03 1937-04-02 Telephone system

Country Status (3)

Country Link
US (1) US2232189A (fr)
FR (1) FR819791A (fr)
GB (2) GB473015A (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2457946A (en) * 1944-02-16 1949-01-04 Automatic Elect Lab Toll metering by discriminating selector repeaters
US2543022A (en) * 1945-08-03 1951-02-27 Standard Telephones Cables Ltd Metering circuit control for automatic telephone systems

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2457946A (en) * 1944-02-16 1949-01-04 Automatic Elect Lab Toll metering by discriminating selector repeaters
US2543022A (en) * 1945-08-03 1951-02-27 Standard Telephones Cables Ltd Metering circuit control for automatic telephone systems

Also Published As

Publication number Publication date
FR819791A (fr) 1937-10-26
GB473003A (en) 1937-10-04
GB473015A (en) 1937-10-04

Similar Documents

Publication Publication Date Title
US2232181A (en) Telephone system
US2232189A (en) Telephone system
US2504708A (en) Selecting-switch for use in telephone systems
US2137423A (en) Automatic switch
US2190140A (en) Telephone system
US1646262A (en) schwartz
US2222126A (en) Automatic switch for use in telephone or like systems
US2262446A (en) Automatic switch for use in telephone or like systems
US2211443A (en) Telephone system
US1831399A (en) Register equipment for automatic telephone exchanges
US2183030A (en) Telephone system
US1468078A (en) Automatic telephone system
GB461082A (en) Improvements in or relating to telephone systems
US2210876A (en) Automatic switch for use in telephone or like systems
US1963929A (en) Telephone system
US2113119A (en) Telephone system
US2597007A (en) Common control circuit for operating switches rearward to calling line
US2289528A (en) Telephone system
US2137518A (en) Telephone system
US2087398A (en) Automatic switch for use in telephone or like systems
US2147235A (en) Telephone system
US2934608A (en) Digit absorbing selector switch
US2787665A (en) Matching register controlled circuit for a switching network
US3487172A (en) Automatic telecommunication switching system
US2207530A (en) Telephone system