US2262947A - Telephone system - Google Patents

Description

F. A. KORN 2,262,947

TELEPHONE SYSTEM Filed Jan. 5, 1940 8 Sheets-Sheet l Nov. 18, 1941.

/NI/EA/TOR F. A. KORN ArToRA/[y Nov. 1s, 1941.

F. A. KORN TELEPHONE SYSTEM Filed Jan. f5,l v1940 8 sheets-sheet 2 lun.-

Nov. 18, 1941. F 'A KORN TELEPHONE SYSTEM Filed Jan. 5, 1940 8 Sheets-Sheet 3 /N VE N 709 A KORN w @www A T TORNF V 8 Sheets-Sheet 4 F. A. KORN TELEPHONE SYSTEM Filed Jan. 5, 1940 Nov. 18, 194.1.e

Nov. 18, 1941. F, A, KQRN 2,262,947

' TELEPHONE SYSTEM Filed Jan. 5, 1940 8 Sheets-Sheet 5 /A/l/ENTOR F A. KORN ATTORNEY Nov. 18, y19111. F. A.KoRN 2,262,947

TELEPHONE SYSTEM Filed Jan. 5, 1940 8 Sheets-Sheet 6 CONNE C TGR /NVENTOR E A. KOR/V AT TOR/VE? Nov. 18, 1941. F. A.'KoRN TELEPHONE SYSTEM Filed Jan. 5, 1940 S'Sheets-Sheet 7 ATTORNEY Nov.l 18, 1941. F. A. KORN TELEPHONE SYSTEM yFiled Jan. 5, 1940 8 sheets-sheet 8 /NVENTOR F'. A KPN www W A TTG/Q1 VEV ,switchboard office.

formation yoperator switchboard office.

Patented Nov. 18, 1941 TELEPHONE SYSTEM Franklin A. Korn, Elizabeth, N. J., assignor to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation o f New York Application January 5, 1940, Serial No. `312,452

8 Claims.

This invention relates to automatic telephone systems and more particularly to information service in such systems.

Experience shows that in the practical operation of large telephone exchange areas, many calls are made each day that need to be routed automatically or manually to an information operator before a connection-can be completed to a Wanted telephone station. Information is required on a substantial percentage of calls from one city or town to another since many calls are made without the knowledge of the station number' of the wanted subscriber. VBecause of the extra effort involved in this service, which includes the holding o-f lines, each information operator is provided with an extensive directory, but in View of the large percentage of stations in the country, this directory must have a limit. On calls to a distant locality information is usually provided by an information operator inthe toll oice area having the wanted subscribers station therein and thus on some calls an extensive connection of toll lines may be held while information is transmitted from one toll ofce to an operator in another toll office where the call was originated. In many instances a connection of this character may involve the use of toll lines of highest transmission efficiency eX- tending long distances. Ordinarily a toll telephone connection is reestablished by the originating operator to obtain the services of a distant toll operator after the information is received. It is necessary for the originating operator to be acquainted with all data for each call and supervise the call after connection is made to the wanted party.

The object of this invention is, therefore, to reduce the holding time of toll lines when information is required by automatically reconnecting an incoming toll line to the toll operator in the toll area having the Wanted subscriber therein, immediately after the information is given to the originating toll operator in order to obviate the necessity of a resignal from the originating operator.

According to the present invention the originating operator may set up a toll connection to a distant toll oice and request that a connection be Vcompleted to an information operators This connection is made by a toll operator in an automatically operable toll office by manipulating apparatus which automatically connects the incoming toll line or trunk to yan outgoing trunk extending to the in- A signal atorindicating the type .o f .call Ito be answered.

The originating operator then gives the code and number designation of the Wanted subscriber to the tolloperator in the :area in which the wanted subscribers station is located. This obviates--the necessity of reconnecting or resignaling for -completing the toll connection.

A feature of thel invention is in a system in whicha telephone call .can be completed to an information operatorxand automatically reverted to a completing ,operator by the .disconnection of the information operator from the calling incoming trunk.

Another and rel-ated Afeature resides .in transfmitting pulses from an information switchboard trunk circuit to `an associated incoming trunk circuit responsive to the disconnection of the information switchboard circuit from the information trunk circuit which actuates the apparatus inthe incoming trunk circuit for interconnecting a Vcalling anda `called operator.

.Another `and related feature resides in a Vsystem 4ofreenergizing .a link .connector responsive tothe disconnection of the information switch-.- board circuit from` the information -v trunk c ircuitfor interconnecting a calling and vacalled operator. v 1

Another and related feature isa system of sigynals for indicating the connection of a trunk from a distant office with Aa cordless toll operators position responsive to the disconnection ko f lthe information operators .switchboard circuit vfrom the information switchboard outgoing trunk.y

These and other features. will be discussed more fully in the Ifollowing description.

To illustrate the features of the invention, reference may be had to accompanying drawings in which:

Fig. 1 illustratesdiagrammatically the association of the different circuits comprising the system disclosed; Y'

Figs. 2 and .3 Aillustrate an incoming intertoll tion of the drawing and a diagrammatic showing Y of the apparatus in an information switchboard in the right portion of the drawing;.

Fig. 4 illustrates cross-bar switches for interconnectingvanl incoming-y trunk' with an outgoing trunk and also illustrates diagrammatically the controlling devices for selecting and operating the switches and outgoing trunks;

matically operable link circuit ralong withthe link 'connector and link control circuit v Fig. 7 illustrates a channelginfazcordless toll-V operators position and partofi' th.-v I'position' equipment;

Figs. 8 and 9 illustrate cor' phone set.v The drawings when arranged, as shown inV Fig. A10,;illustrate the detail structurev ofA this system.

GENERAL DESCRIPTION y f vThe elements of a system inwhich'the invention maybe incorporated are illustrated diagrammatically in Fig. -l which shows adistant toll ofce l interconnected byftrunk conductors with the incoming trunk 2 1of-an automatically operable toll` oflice. Only'one distant toll oce ris shown,`but there maybe a large pluralityfof ofdless "toll :'operators position equipment including theoperatois tele-V nector 8, and control circuit 9 for selecting an idle channel entering one of a plurality of toll operators positions III. Each toll operators position may have a plurality of channels entering the position circuit so that more than one calling incoming trunk may be associated with the position equipment at the same time. For example, an operator may receive a1call over one channel and 'set the'registers inthe sender for completing this call. The operator may then im- ",j'mediately disassociate the calling trunk from the Fig. 6 illustrates the switches of an -autocommon position equipment and associate an- "other incoming trunk with the position equip- 'ment for answering vanother call. During this period the registrations made in the sender for the first call have been transferred to the marker yand the marker has accordingly set the switches v'3 and 4 for connectingthe incoming trunk to an outgoing trunk as designated, As soon as the connection has been completed by the marker the sender II and the position channel maybe released from the connection. This channel is then free for another incoming call to the posif icesentering the tollonice through ajlarge plurality; of incoming trunks.'r The automatic operabletoll ofce comprises ya pluralityof incoming trunkswhich are associated 'witl'iftoll call complating operators positions I0; through link switches f'I under the c'ontrol f o`f-'se1ectable link connectors 8 and selectable-link controlcircuits 9.A A large plurality of outgoing trunks are included inthis tolloice for reaching other offices andl subscribers vassociated therewith -`lor for reachinginformation operators for obtaining subscribers-call designations. Anloutgoing'trunk to another officeH I'4- is Ishown at I3 ,an d jan outgoing trunkto the information 'ope'rator 6 is shown at 5.- lSwitchesa and '4p are shown for connecting incoming trunks to outgoing `trunks either fe'xtending to the information'V 'operators positionorfto the distant oiceal' These switches are lunder the controlof the toll operators position I'0 by the registration of av code designation in the sender I'I. Theseregistrations controlthe marker I2 for 4operating the switches for connecting theincoming trunk to either aninformation"operatorsoutgoing trunk'or an voutgoing trunk: to atollofce selectedA by the marker accor'din'gfto the registrations therein.

' office I has called for a wanted party in another city,v a -connection is completed to atoll ofcein this other city which@v may have'equipment as diagrammatically shown. The tollY operator in the' distant-cnice I actuatesthe apparatus of the incoming trunk wZwhich automatically causes the as'sociationof a'link' I between thisincoming trunk circuit and a cordless operators position -II).` yAn automatically operable link which may be ,used f or" such connection is' disclosed in the patent application to King-.McKim-Myers, Serial No# 2195,010, led September 15,* 1939 lissued as PatengNo. 2,236,246, March 25.,.,1941 and" in the patentgapplication; to Busch-Scudder, Serial No. 295,012, l'e'd'Sep'tembe'r 15, 1939:; vThischaracter of ,link is actuated by 'a Vcalling @incomingl trunk 'for associating therewith',y af' common link contion I0. When the channel is released theoperators position II) is entirely disassociated from the calling incoming trunk and the telephone connection which has been completed through this trunk t0 any information operator or a distant cnice. l

It may be assumed for this disclosure that the calling subscriber entering the distant office I does not know the wanted subscribers telephone number and that therefore the operator in the distant toll office I requests the toll position operator I0 to extend the connection to the information operator 6. The registers of the sender are set bythe toll operator in position I0 according to the code of an outgoing trunk extendingto the information operators position. YThis outgoing trunk 5 extending to the information ope'rators switchboard 6 and Voperates the correct switches 3 and VII for connecting the Ycalling 'incoming trunk with the information operators outgoing trunk. A signal is" lighted in the infor- 'mation operators switchboard to indicate `that 'information is required byfl a calling subscriber orcalling toll operator. After the request'is made by the distant toll operator I the information operatorrefers to her directory and supplies the designation and number of thewantedsubscribers line to this distant toll operator. `"l'he information operator now disconnects-the 'information switchboard apparatus from lthe information operators outgoing trunk 5. By `this time 'theftoll operators position equipment and the channel in position I0 may havebeen disconnected from the incoming trunk vso that theoperator in position III may handle other callsentering the channels of the' position.' The link switches 'I may also have been-restored 'to normal so that at this time there is no Yconnection between the calling 4incoming trunk andthe toll operators position I0. The yoperator in toll oce I is given the infomation so that a record of the called partys designation may be made by the originating operator.

According to the present invention the disconnection of the information switchboard operating circuit from the vinformation operators outgoing trunk 5 energizes equipment in thisoutgoing trunk rfor reconnecting the calling incoming trunk to a channel of one of the toll operators positions such as I0. The equipment of the information operators outgoing trunk immediately energizes apparatus in the incoming trunk for actuating link switches such as 1 to obtain a channel into an idle operators position. This reassociates the distant toll operator I with a toll operator in an idle position I so that the vdistant operator I may immediately transmit the wanted subscribers designation to the toll operator in position I0. On certain types of toll calls supervision is retained by the to-ll operator in position I0 and under this condition the link may be automatically locked between the toll position and the incoming trunk. Under this type of traf- Aiic the equipment of the outgoing trunk energizes the equipment in the incoming trunk for giving the toll operato-r in position I0 a distinctive signal to indicate that the information operator has transmitted the called partys designation and that the distant toll operator again requires her attention for completing the telephone connection. It is well understood that the usual procedure' for obtaining information has been different. The originating operator after obtaining the wanted subscribers telephone designation rfrom the information operator would again set up the telephone connection the same as when making the original call to obtain access to this information operator, which necessitates a loss of time and undue retention of the toll lines.

When the toll operator in position I0 has received the party designation from the distant office I, registrations are again set up in sender I I for selecting an outgoing trunk I3 to an ofiice having the Wanted subscriber therein. These registrations are transferred to the marker I2 in the same manner as for obtaining an outgoing trunk to the information operator and switches 3 and 4 are energized for associating the incoming trunk with the outgoing trunk I3 extending to the distant office. The subscriber in office I4 is then connected to the calling subscriber entering the distant toll office I.

DETArL DESCRIPTION The assumption is made that a call has been received by a toll operator in the distant toll ofce 200 and that the subscriber making this call does not know the call designation of the wanted party and that the operator in the distant oflce 200 does not have a directory covering the subscribers designations and station numbers in the distant city where the station is located. This toll operator in the office 200 will, therefore, establish a connection to the toll oice in the area in which the called party is located and obtain the called party designation from an information operator in that city. Under present trailic conditions this connection is made to the information operator in the distant city, who transmits the called party designation to the originating toll operator. A second connection is then completed from the toll oliice 200 to the same toll `oiice for completing a ycall to the wanted party but, as previously stated, according to `the present invention, only one call to this toll office is required for reaching both the information operator and for completing the connection to the Wanted party. In the present disclosure the distant office 200 is connected to the toll oiiice having the wanted party therein by a ringdown intertoll trunk which is energized by transmitting ringing current from office 2.00 over toll CTI trunk conductors 240 and 24| to the incoming trunk of this oflice shown in Figs. 2 and 3. After the distant operator in office 200 has completed the operation of apparatus for the connection to the trunk, this ringing current is applied automatically or manually to conductors 240 and 24| and transmitted through the winding of alterhating current relay 202 which is energized. The energization of relay 202 releases relay 205 which is normally energized from battery through its winding to ground on the contact of relay 202. The release of relay 205 establishes a circuit for operating the incoming trunk relay 302 over a circuit from battery through the Winding of relay 302, contact 2 of relay 205, contact 1 of relay 220, contact 6 of relay 3|| to ground. Relay 302 in operating establishes a locking circuit for itself through its contact 3, contact 1 of relay 220 to ground and contact 6 of relay 3| I. When ringing current is disengaged from the -trunk conductors 240 and 24|, relay 202 releases Which reenergizes relay 205. A circuit is thus established for relay 2|3 from battery through its winding, contact 5 of relay 2|2, contact 2 of relay 205, contact 3 of relay 302, contact 1 of relay 220, contact 6 of relay 3|| to ground. Relay 2I3 is locked through contact y4 of relay 30|, contact S of relay 2|3 to its operating ground on contact 6 of relay 3| I. The operation of relay 213 now establishes a start circuit for a link which associates the incoming trunk and the operator at oince 200 with the cordless operator whose telephone apparatus is shown in Fig. 9 of this disclosure. This link start circuit may be traced from ground through contact 3 of relay 2|3, contact of relay 2|2, lead 343, winding of link start relay 6|0 to battery. The link connector and link control circuit is shown diagrammatically and only a brief description of associated elements is given. Reference is made to the patent application to King et al. Serial No. 295,- 010 filed September l5, 1939 for a ycomplete disclosure of this link connector andv link control circuit.

The energization of the link connector start relay establishes an obvious circuit for a `relay such as relay 6|I which is a multicontact relay for connecting a large number of leads Yfrom a plurality of link switches, trunks and position channels with the link control circuit 601. There is a plurality of selectable link control circuits 601 which plurality is small compared to the large number of switches 600 and 60|. The link connector 006 finds an idle link 'control circuit before operating the multiconta'ct relay GII for connecting a number of position channels with the link control circuit and a group of trunks having the calling trunk 'therein with the link control circuit. The switch 600 is one representative primary link switch of a plurality*i of horizontal levels and verticals constituting primary link cross-bar switches. Switch 60| is one representative secondary link switch of which there are a large plurality in vertical and horizontal levels connected to channels in a plurality of cordless toll positions. The function of the link control circuit is to test a .plurality of channels entering a number of cordless toll positions to obtain an idle channel and the services of the toll operator lin the cordless position to which this channel is connected. In View of the fact that each channel is connected to a different switch, such as 60|, the test of the channel determines the secondary switch to .be used. This secondary switch is connected to a particular vertical of a primaryswitch such as 600 and the horizontal level of this primary switch is connected to the calling incoming trunk The hold magnets for these primary and secondary switches are in multiple as shown.

An idle channel in a position having an operator in attendance has battery on lead 130 and ground on lead 13|. Ground is placed on lead 13| by the operation of relay I0I actuated when relay 1|5 is actuated. Relay 1|5 is only actuated when an operator is serving the cordless position. The circuit for relay 1I5 may, thus, be traced from battery through its winding, contact I of relay 102 to ground through jack 904 which has its contact closed when the telephone operators headset plug 906 is inserted therein. Relay has as many contacts thereon as there are channels in the position and its operation makesfall channels idle which are not in use as will be seen from the description of the channel apparatus. The testing apparatus of the link control circuit is such that when battery is found connected to lead 130 and ground is 'found connected to lead 13| a relay, such as 6|4,

is energized. 'I'his relay is not directly energized as shown,`but is energized by delicate testing apparatus in this control circuit responsive to a test of the position channels. Other apparatus is included in the control circuit, as fully described in the aforementioned patent application to King. et al. which determines the primary switch, such as 600, which is connected to the calling trunk and the secondary switch, such as 60|, which is connected to the idle channel found by the control circuit. When this has been determined, the primary select magnet 602 is energized from ground through its Winding, contact of multicontact, relay to'battery on the contact of a control circuit relay.` The select magnet 603 of the secondary switch, connected to the idle channel, is also operated from ground through its winding, contact of relay 6|| to battery on a contact of a control circuit relay. The closure of the contact of select magnet 602 establishes a circuit for control circuit relay 6|3 and the closure of the contact on select magnet 603 establishes a circuit for relay 6|2. The circuit for relay 6|2, it will be noted, extends through the contact of relay 6| 4 oper- .ated by the testing'apparatus of the link control circuit. The operation of relays 6| 2 vand 6|3 establishes a circuit for the hold magnets of the primary and secondary switches. This circuit may be traced from ground through the contacts of relays 6I3 and 6I2, contact of the multicontact relay 6|I, winding of hold magnet 604 to battery and the winding of hold magnet 605 to battery which closes the cross-points of the primary and secondary switches 600 and 60|. 'I'his connects the incoming trunk, Figs. 2 and2, with the channel and toll position apparatus shown in Figs. 7, 8 and 9. Y

Position channel Relay 1|| is immediately operated `from battery through its winding, contact 3 of switch 60| to the ground on the contact of relay 6|3 used for operating the hold magnets. The operation of relay 'III removes battery from the lead 130 and ground is associated therewith. Ground is disassociated from lead 13| and this lead remains open. Relay 1|0 is also operated from battery through its winding, contact 2 rof relay 103, conductor 625, contacts 1 of switches 60| and 600, lead 331, contact 2 of relay` 2I2 to'ground on Contact 2 of relay 2|3. The operation of relay 1 establishes obvious circuits for lighting the busy lamp 101 and the guard lamp 106. Y Relay 1| 0 establishes an obvious circuit are in a chain circuit to prevent seizure of more than one channel at a time as shown in the aforementioned patent application to King et al. The circuit for relay 102 may be traced from battery through its Winding, contact of relay 1|0, contact 3 of relay 1|I, contact 2 of relay 102, contact of relay 1|5 to ground. Relay '|02 in operatingxestablishes a locking circuit for itself from battery through its winding, contact I of relay 1|0, contact 3 of therelay 1|I to ground through contact 2 of relay 102. This relay also opens the operating circuit for relay 1|5 extending through its contact I and establishes a circuit for relay 1|3. The circuit for relay 1I3 may be traced from battery through its winding, contact of relay 102 to ground on the contact of the operators jack 904. The re- -lease of relay 1I5 opens the circuit for relay 10| to cause its release so that all channels of the position are made busy during the period required by the operator in serving the callr entering her position. The operation of relay 1`|3 establishes a circuit for operating relay 103 from ground through contact 4 of relay 1|2, contact 6 of relay 1|3, winding of relay 103 to battery and alters the guard lamp 109 from a steady to a ilashing condition by the connection of ground through its contact 3 and contact 4 of relay 1|| for the hold magnets 604 and 605 and forlocking relay 1| I. The switches 600 and 60| are, therefore, no longer dependent upon the link control circuit for maintaining-their holding circuit. The operation of relay 103 closes circuit paths for the talking and signaling conductors from the link switch and incoming trunk to the cordless position apparatus, opens the locking circuit for relay 1|0 which restores to normal and closes an operating path for relay 104. The circuit from relay '|04 is established from ground on the contact of a relay in the position control circuit not shown, through contact 9 of relay 103, winding of relay 104 to battery. This position control circuit may be the same as disclosed and described in detail in the aforementioned patent application-to King et al. Serial No. 295,010 led September 15, 1939.

Link vrelease establishes a locking circuit for itself to ground on contact 8 of relay 3:|| through a circuit including contact 5 of relay 2| 3, contact 2 of relay 285, contact 3 of relay 302, and contact 'I of relay 220. The operation of relay 212 removes the start circuit ground from lead 343 which extended through its contact I and causes the release of relayY 6|0- in the link connector circuit. The release of relay BID causes the release of relays 6|| and 8|3. Relays 6|'2 and BUIr were released when the position channel was made busy. This link connector apparatus and the link control apparatus are now released and may serve other calls entering the telephone oice. As previously stated, a ground is supplied from the position circuit for maintaining the hold magnets 604 and B05 operated and, therefore, the switch connection between the position channel and the trunk to the calling oice 200 remains established.

Position circuit A circuit is now established for energizing the splitting relayy 30|- for separating the inward and outward ends of the trunk circuit. This circuit may be ltraced from battery through the lower winding of relay 30|, contact 4 of relay 2-I2, lead 33E, contact 6 of switches 600 and 80|, lead 626, contact 8 of relay |03 to ground on the contactl of a relay in the position control circuit or key '|27 when actuated by the toll operator. A circuit isalso established for relay 2|3, traced from battery through its winding, contact 4.0i relay 38|, contact 4 of relay 2|2 thence over lead 335-to ground connected to contact 8 of vrelay '|03 over the circuit traced for operating the splitting relay 30|. The forward end of the trunk is now connected with thev cordless position circuit.

' Position signals The forward relay, such as '104, of the position channel is operated if no other forward relay in a sequence circuit of the channel is operated. Ther circuit for this relay is established whenthe backward relays '|03 and H3 of the channel are operated. An arrangement of signals is provided which Aare operated by relay combinations in the position circuit under the control of apparatus in the incoming trunk circuit operated in response to incoming-calls or recalls, such, .for example, as the apparatus of the ring-down incoming4 intertoll `trunk circuit, Figs. 2 and 3, or incoming intertoll trunks of other characters which have apparatus responsive to diierent signals transmitted over the toll lines or trunks. The operation of apparatus in the incoming trunk circuit under diiTerent conditions connects battery through different values of resistance over lead 33T-to the position circuit. This lead 33'! may be traced to the position circuit through contacts? of the link switches, Fig. 6, to lead 625, contact 2 of relay 103 and thence through the windings of marginal relays 8|4, 8|5 and 855 to ground. The number cf these relays operated depends upon the value of resistance associated therewith responsive to calls of difierent character. For example, when ay call is a new call for connection to an outgoing toll trunk, relay 2|2 is operated which associates resistance 230 in circuit with relays 8|4, 8|5 and 8|8. The value of resistance 230 is such that only relay 8|4 is operated. This establishes a circuit for relay 883 from battery through its winding, normal contact of relay 8|5, contact of relay 8|4 .18|4, SI5', 8|6, 802 and 803.

tol ground. Thisr causes the transmission;y of la distinctive tone to indicate lthat the call vto be answered bythe cordless operator isa newlcall. In this case the apparatus of the position` control circuitwill establish a circuit -for relay 8I'I.

For a recall `from the calling distant operator,`

the same circuit will be established with the exception that relay l828 in the position control circuit is operated and there will be not circuit for operating relay 8H; therefore, on a recall, a circuit is established to light lamp 8|0 `and a distinctive tone is transmitted to indicatethis type of call. When a recall is made from the` information operatorslvv trunk disclosed in Fig.

I 5, circuits are established for relays 2|2, 3|'I and 3|2 of the incomingtrunk circuit, ligs.2 and 3.

The operation of thev above three relays connects resistances 322 and'230 in multiple and these multiple resistances are connected in series circuit with relays 814, 8|5 and 8I6. resistance 322 in multiple with resistance 2-3'0 is such as to cause the operation of relays 8|4 andv 815.

with the-operators headset.- A differentr signal is given when the distant called party does not answer. In this case, incoming vtrunk relaysr 2|2 and 3|I are operated which connects resistances 32| and 230 in series with relays 8|4,

8|5 and 8|6.- The value of resistance 32| in multiple with resistance 230 is-/su'ch as to cause the operation of all of the above relays. The' operation of these three relays establishes` an y obvious circuit for both relaysl 802 and 803 which' lights lamp 8 2 through their contacts and establishes a circuit for a distinctive tone. l

The ltone circuit, known as the'order tone, for indicating to the operator that av particular connection has been established which is either a new call, a recall ror that the connection desiredV acteristic' circuit to the marker.' With these re' lays released, circuits are established for indicating that th'e callis from a `straightforward intertoll trunk. In the case where both relays are released three pulses of order tone are trans--l mitted to both the distant operator and the cord- .ffl less operator.- When only one of theabovev re-' lays is operated, the tone will be transmitted only to the cordless operator. O-ne pulse of tone is transmitted when relay 802 is operated and two pulsesof tone are transmitted when relay 803 is' operated.`

Position tone circuit Theorder tone relay operating lcircuit is established from the position control circuit which associated ground with lead 820 through contact 4 of relay 804, lead 830, vcontact 4 of relay 820, contact 4 of relay 8| 8, winding of relay 82| to battery. The operation of relay 82| is the first of a series of operations for energizing and deenergizing the tone circuit. This tone circuit y may be traced from tone -source 822 through various contacts of relays 8|3, 8|8, 8|0, 820 and 82| thence through the right winding of tone transformer 805 to ground. When either or both i relays 802 and 803 are operatedthe tone is trans- The value of The operation of both relays 8I4 and 8|5v establishes an obvious circuit for relay 802 whichlights lamp 8|| and' associates a distinctive tone' mitted by induction throughtoneftransformer 805, contacts I and of relay 804 to the talking conductors which in one case extend through contacts I and 4 of relay 90| andthe windingsrelays 80| and 800, contacts Sand 4 'of relay 'I03,V

leads 630 `and 63I Vover the trunk conductors to thedistant operator in office 200 in addition to being transmitted to the cordless operaton The sequence of operations ofthe tonerelays is as follows: Relay 82| operates to ground-83| as previously traced. The operation of this retone circuit for transmitting three toneswhichis the maximum used in this circuit arrange'- ment. As previously explained three tones are.l used when the toll call is incoming over straightforward trunk and may indicate a newY call over this trunk or a recall by the originating distant operator.

or when it is a recall from the originating voperator. A recall from the information operator operates relay 802 and when the called party does not answer both relay 802 and Yrelay 803 are operated but relay 802 is the only one effecting the control of the tone circuit. Under the conditions of a newcall or recall from-the originatlay establishes a circuit for relay 820 to the same ground through contact 4 of relay 82| and'` contact 4 of relayr8|9. The operation of relay 820 closes the tone circuit through its contact 3 'from` the tone source 822 and the tone coil 805. Relay 820 locks through its contact 4 and contact 4 of relay 8I9 which opens the operating circuit for relay 82| and the latter relay releases. A circuit is thus established for relay 8I9 through contact 5 of relay 820 and contact 3 of relay 82|. The operation of relay 8I9 opens the tone circuit for ending the rst impulse of tone. The circuit for relay 820 is opened by the operation of relay 8I9 causing its release. A circuit is now established for relay 8I8 through contact I of Vrelay 8I9 and a locking circuitis established through its contact 3. This sequence of events again establishes an operating circuit for relay 82-I` through contact 6 of relay 8I9`and contact 4 of relay 820. The circuit for relay 8I9 is thus opened causing its release. A second impulse of tone is started by again closing the tone circuit through contact I of relay 82|, contact I of relay 820 normal, contact YI offrelay -8I8 which is operated, and through' coil 805 to'grour'id. A circuit is thus established for relay 820y which is the same as the circuit over which it was previously operated. 'A circuit-isalso established for relay 8| 3 through contact 2 of relay 8I8,` which'is held locked, contact 2 of relay 820 'and contact I of relay 8I9 to the original ground as traced. Relay 8| 3 locks to this same ground.

ing operator using an incoming ring-down intertoll trunk the operation of relay 803 causes one pulse of tone to be transmitted only to the cord less operator. The talking circuit to the incoming trunk is opened to-contacts I and 5 of relay 803 and thus this one pulse does not reach the incoming trunk. The operation of relay 803 establishes a circuit for relay 804 after one pulse of tone has been transmitted. This circuit'may be traced from battery through the winding of,v relay 804, contact 2 of relay 802 which is nor-r mal, contact 2 of relay 803, operated, contact Il of relay 8I9 which is operated at this time and thence to ground over leads 83!!` and 829 through contact 4 of relay 804. Relay 804 in operating; separates leads 830 and 829 and locks through As previously stated' its contact 4 to lead 829. theoperation of relay 804 releases the tone actuating relays and ends thetransmissionof tone The operation of relay 802 on ajv recall from an information operators desk causes after one pulse.

the transmission of two pulses yofv tone to the cordless operator. These pulses do not reach the incoming and outgoing trunks. The operation of the tone circuit relays proceeds as previously described until relay 820 operates a second time.

The operation of relay 820 opens the circuit for this relay, This closes the tone circuit for athird v impulse of tone and opens the circuit for relay 820. This is the last tone circuit established and'may be traced from the tone source "822 through contact I of relay 82|, contact 2 of relay 8I9, contact 3 of relay'8l3, winding'of the tone coil 805 to ground. Relay 82| is now lenergized through contact 6 of relay 8I9, contact 4 of relay 820 over leads 830.and 829 to the original ground. The operationof relay 82| opens the tone circuit and terminates the third impulse of tone and also establishes a circuit from battery through the winding of relay'804, vcontact Ilof relay .8I3, contact 2 of relay 820,.contact 2 of relay 82| to the original ground. Relay 804 in operating establishes alocking circuitforitself through its contact 4 to ground over lead 829. The operation of relay 804vseparates leads 829 and830 at its'contact 4, thus releasing all of the relays which were held to this ground including 8I3,8I8,andr82l. 'Y

The foregoing describes the A circuit is thus established for relay 804 from battery through its windings, inside contact 2 ofi` previously described and locks through its con-r tact 4 to lead 829. The foregoing indicates thev action in the cordless toll operators position cirf cuit both for a new call entering this position as' previously described, and fora recall frornthe Y information operators desk vwhich occurs in ay manner to be presently described.

Toll operator The cordless toll operator challenges the call-l ing operator in toll ofce 200` when she observes the flashing lamp 109 and hears the single pulse of tone. vAs previously stated, this descriptionv and the marker 4I6 vwhich operates the cross-v bar switches of Fig. 4 for connecting the incoming intertoll trunk, Figs. 2 and 3. with an outgoing trunk, Fig. 5, extending to an information operators position in an information switchboard office disclosed diagrammatically in the operation Vof the right portion of Fig. 5. Reference is made to `the Patent 2,236,246 to King-McKim-Myers March 25, 1941 for a complete description of the cordless toll position equipment, position control cir- A call from an originating' op-` erator over an incomingring-down trunk actu-' ates relay 803 eitherwhen this call is a new calll cuit, position sender 4|5 andr marker 4| 6 for operating the apparatus of this ofce to complete the connection between the incoming intertoll trunk and the information operators trunk.

As covered in the aforementioned patent application to King et al. the cordless toll operator sets a plurality of keys in her key-set for registering the code designation of the information operators outgoing trunk in the position sender 4|5. The code designation from the sender 4|5 isy transmitted to the marker 4|6 along with other information including the character of the calling incoming trunk which sets the registers in the marker for completing the connection. The apparatus of the marker is automatically operated for testing a plurality of trunks extending to the information operators switchboard. Such trunks are represented in the marker on what are known as trunk block or trunk group relays which may be associated in groups with the testing apparatus of the marker. When an idle outgoing trunk to the information operators switchboard is found, a ground is connected with a relay such as relay 503, shown in the information operators trunk circuit, Fig. 5. A number indicating system is included in the marker in order that the location of switches, such as switch 404, connected to the information operators trunk and switch 40|, connected to the calling incoming trunk will be designated to the marker. This designation enables the marker to nd an idle junction between switches 40| and 404V constituting switches 402 and 403 and their connecting conductors. The control relays 4|3 and 4|/4 are operated for associating theY marker with the switching apparatus associated with the switches 40|, 402, 403 and 404. This idle junction having been found', the select magnets 405, 406, 401 and 408 Iare operated and the hold magnets 409, 4|0, 4|| and 4|2 are operated to close the contacts of the switches involved for connecting the incoming trunk, Figs. 2 and 3, with the information operators trunk. Fig. 5. When the contacts of the switches 40|, 402, 403 and 404 have been closed a ground is extended from the incoming trunk for maintaining the hold magnets operated after the marker is released from this connecting apparatus. This ground maybe traced through contact 4 of the incoming trunk relay 302 which is operated, contact 9 of relay 30| normal, thence through the switch contacts, through the windings of each of the hold magnets 409, 4|0, 4|| and 4|2 to battery and also through the winding of the information trunk relay 503 to battery. The association of this ground with the sleeve circuit of the switches and the sleeve on the outgoing trunk energizes apparatus in, a potentiometer circuit of the marker as one phase of the marker release circuit.

Trunk lines The cordless toll operator energizes one of two relays in the intertoll trunk circuit, depending upon the destination of the telephone connection. When the telephone connection is made to what is known as a terminating station, relay 2| 1 is operated through the actuation of key 122. In certain instances this circuit is established automatically by the position control and marker apparatus as fully described in the patent application to J. B. McKirn Serial No. 312,468, led Jan. 5, 1940.

The circuit for relay 2|1 may be traced from ground through resistance 124 of the potentiometer associated with key 122, thence through contact 4 of relay 104, lead 622, contact I0 of switches 60| and 600, lead 340, contact 1 of relay 2|3, winding of relay 2|1 to battery. The operation of relay 2|1 does not establish circuits in the incoming trunk at this time and is used for signaling paths responsive to circuits established at the outgoing end ofthe trunk. When a connection is extended through a distant toll oilice for a via connection using a high efciency toll trunk, key 12| is energized which establishes an operating circuit for relay 2| 4 in the incoming intertoll circuit or this circuit may be automatically established by the marker and position circuit. This circuit may be tracedl from ground to the potentiometer associated with key 12|, contact of key 12|, contact 5 of relay T04, contact of switches 60| and 600, leadr 34|, contact of relay 2| 3, winding of relay 2|-4, to battery. A locking circuit is establishedvfor either relay 2|1 or 2|4 through contact 9 of relay 30|, contact 4 of relay 302 to ground. As previously stated, a supplemental locking circuit is held closed from the position circuit if at any time relay 30| is operated. Under certain circumstances, key 123 may be operated which establishes circuits for both relays 2|4 and 2|1. The operation of relay 2|1 either automatically Aor manually by the actuation of key 12| or key 123 establishes a locking circuit for switches such as B00 and 60| channel in a cordless switchboard position. This circuit may be traced from ground on contact of relay 2|4, Iover lead 333, contact 3 of switch 600, winding of hold magnet 604 to battery, winding of hold magnet 005 to battery and winding of channel relay 1|| to battery. Thus, a holding circuit is established which maintains signaling paths between the incoming trunk and associated apparatus and the cordless toll operator position so that if at any time a signaling circuit is actuated from the calling or called parties the cordless toll operator is advised byA the actuation of a signal and may immediately respond by associating vthe position apparatus with this channel. When relay 2|1 is energized no holding circuit `is established for the switch hold magnets and the channel is, therefore, released when position relays and 130 are either automatically operated by the release of apparatus in the sender and p-osition control circuit or are manually operated by the actuation of key 1|`4. Under present practices, it is only possible to obtain the services of the cordless operator by manually initiating a recall from the calling or the called office.

' Information desk outgoing trunk Aspreviously stated, relay 503 in the informa-- tion desk outgoing trunk was operated when this trunk was seized by the marker 4|-5 and as soon as-the cross-bar switches, Fig. 4, were operated and the hold magnets associated with these switches energized, ground is associated with the hold magnets of all of the switches, Fig. 4, and with relay 503, Fig. 3, from the incoming trunk circuit, Figs'. 2 and 3. This ground is constantly maintained either from the incoming trunk circuit as traced or by a ground from the cordless position circuit when the splitting relay 30| is.

operated. When the splitting relay 30|' is operated by ground from the position control circuit' or key 121 another ground is also established through contact 5 of relay 1|3, lead 02,4,`

associated with a particular contact 9 of switches 60| and 600, lead 339, 'and thence over the sleeve lead to the hold magnets 409, 4|,0, 4|| and 4|2 and trunk relay 503.i The operationv of the cross-bar switches,` Fig.l 4,also establishes a circuit for trunk relay 504. This circuit extends from battery through the winding of'relay 504, contact 4 of relay 504, lead 522, winding of retardationcoil 50|, thence over the ring conductor 520 and the contacts of the cross-bar switches, Fig. 4, to conductor 350 of the incoming trunk circuit, through retardation coil 303,?contact 8 of relay 302 which is operated, lead 338,- contact 8 of the link crossbar switches 600 and 60|, lead 623, contact 6 of relay 104 which is operated, contact of relay 1|9, normal, and through the high resistance winding of relay 1|1 to ground. Relay 1|1 operates in the circuit traced but relay 504 does not operate due to the high resistance of the right winding of relay 1|1. An obvious circuit is established for relay 1| which locks to ground through a position sender relay contact which is not shown. The operation of relay 1|8 connects ground from its contact 2 through the low resistance left winding of relay 1|1, thence over the circuit traced above through the winding of information trunk relay 504 to battery. Relay 504 now oper ates and locks to ground on the contact of relay 503. Relay 504, in operating, removes battery from the ring conductor extending through the cross-points of the cross-bar switches and through both windings of relay 1 I1. This causesv the release of relay 1|1. With relay 1|1 released and relay 1|8 operated an obvious circuit is established for relay 1|9 which operates. Theopen lead 522 in the information operators trunk circuit, Fig. 5, is now connected to the lament of the supervisory lamp '|06 through contact 6 of relay 104, contact of relay 1|9 and contact 1 of relay 104 to a junction between resistance 132 and the lament of lamp 106. It will be remembered that during the period when the apparatus of the ofce including the position channel sender and marker are in operation for setting the switches of Fig. 4, a circuit is constantly established for lighting lamp 106 from battery through its filament to ground on contact 6 of relay 1H. The circuit arrangement established by relay 1|9 is for `supervision, from the distant end to shunt lamp 106 whenever ground is associated with lead 522. A ground placed on lead 522 through a low resistance, such as the winding of retardation coil 50|, will shunt the battery supply for lamp 106 and thus extinguish the lamp.

The operation of the information operators trunk relay 504 establishes a lamp signal in the operators position. The circuit for this lamp may be traced from battery through resistance 501, contact 3 of relay 504, contact of relay 509 to ground through the filament of lamp 508. The information operator answers this signal by operating key 5|0 which associates the operators telephone circuit with the talking conductors of the trunk and operates relay 509'. The operation of relay 509 extinguishes lamp 508. The association of the operators telephone circuit with the tip and ring conductors energized relay 502. This circuit may be traced from ground throughthe upper winding of relay 502, thence over the tip conductor of the trunk, upper contact of key `5|0, windings of coil 5|3, lower contact of key 5|0, ring conductor of the trunk, contact I of relay 504, lower winding of relay 502 to battery. The operation of relay 502 connects ground through its contact, contact 2 of relay 505 normal, contact 2 of relay 504, winding of relay 505 to batt-ery which operates relay 505. Relay 505 locks toground through its contact and contact 2 of relay 504 and thus remains operated until relay 5031s released since the relay 504 is locked to ground on the contact of relay 503. The information operator is now connected through her telephone set, shown in the right portion of Fig. 5, with the toll operator at the distant toll oflice 200, and a ground is connected to lead 522 for signaling theA cordless operator that such connection has been completed. This ground may be traced from the contact of relay 502through contact 2 of relay 505, contact 4 of relay 504, lead 522, thence through the winding of retardation coil 50| and over the ring conductor 520 to extinguish lamp 106 in the cordless operators position over a. circuit as previously traced. At this time the cordless operator may disconnect the cordless position apparatus and link apparatus from the connection by the operation of keyl 1|4- which operates relay 135 to open the locking circuit for trunk circuit relay 2|3 which releases. The release of relay 2|3 opens the locking circuit for splitting relay 30| which releases. The operation of relay 'causes the operation-of the slow operate relay 136 which releases relay 1|3 andtheremaining position and channel apparatus. 4The position channel associated with the link switches 600 andY this locked channel by the operation of key 1|4v and, consequently, the cordless operator may handleother calls until such time as a signal is received requiring attention to this particular channel. The channel apparatus yis released with the exception of relay 1| The release of relay 104 connects the shunt path for lamp 106 directly through its contact -6 to the trunk line connection. Y

A circuit is established for operating the timing circuit 2|0fro-mV i-nterrupter 2|5 or 2I6 de` pending upon the relayr2 |4 or 2|1 operated, and for loperating the timing relay 208.y This timing circuit is included in the incoming trunk circuit in order to signal the operator if the called partyv does not answer within a limited time andfor establishing other signaling circuits as will be apparent. The circuit for relay 203 may be traced from 2li-volt battery 325 through its winding, through relay contacts in the timing circuit 210, contact 3 of relay 20|, contact4 of relay 206,

contact 2 of relay 3|3, contact 4 of relay 2|3 to ground on` contact 3 of relay 2|4 or contact 3 of relay 2|1. was connected to lead 522 when the information operator actuated key 5| 0. This ground extinguishes supervisory lamp 106 in the cordless operators position unless the position apparatus has been previously disconnected. The connection of ground to lead 522 energized relay3|3 which was not included in the fo-regoing description.

Relay 3|3 isa differentially connected relay hav.4

It will be remembered that a ground ing its windings normally connectedv together through a contact of relay 302. This relay does not energize in this local circuit which may be traced from ground through the left Winding of relay 3l3, contact 5 of relay 302 to battery through the right Winding of relay 3I3. When ground is connected to lead 522 extending through the winding of retardation coil 50| and over the ring conductor, a circuit is established through retardation coil 303, contact 8 of relay 302, contact 9 of relay 2I3, contact I0 of relay 30| to battery through the right Winding of relay 3I3 which unbalances the current in this relay and causes its operation. The operation of relay 3I4 establishes a circuit for relay 3I8 from battery through its Winding, contact I of relay 3I2, contact 4 of relay 3I3, contact 8 of relay 2I3 to ground through contact 2 of relay 2I4 or contact 4 of relay 2II. The operation of relay 3I3 also causes the release of timing relay 208 by associating Ll8-volt battery 324 in circuit with the 24-volt battery 325. This circuit may be traced from .4S-volt battery 324 through contact 3 of relay 316, contact 2 of relay 3I3, contact 4 of relay 208, contact 3 of relay 20|, timing circuit 200, Winding of relay 208 to .Z4-volt battery 325. The circuit for operating relay 208 extended from ground to the 24-volt battery and the reversal of current in the Winding of relay 208 causes its immediate release. 'Ihe release of relay 208 opens the circuit for the relays included in the timing circuit 2I0 which alsorelease. When the relays of the timing circuit 2 I0 have all released a circuit is reestablished for the timing circuit relay 208 which now operates from 24-Volt battery 325 to the 48-volt battery 324 over the circuit as previously traced. The reestablishment of the timing circuit relays establishes a circuit for operating relay 3I6 which circuit may be traced from ground through contact 3 of relay 208, contact 4 of relay 20|, contact 3 of relay 3I3, Winding of relay 3I8 to battery. Relay 3I6 locks through its contact 2 to ground on contact 2 of relay 2I4 or contact 4 of relay 2 I'I. `The operation of relay 3 I E again opens the circuit for timing relay 208 which releases and again releases the relays included in the timing circuit 21.0.

Automatic recall of cordless toll operator The information operator responds to the signal given by lamp 508 and operates key 5I0 as previously described, This information operator then requests what information is desired and gives the `telephone designation and number of the Wanted party to the calling distant toll oper- .ator in telephone oilice 20.0. This information operator then disconnects by restoring key 5I0 to normal which releases relays 502 and 509. The release of relay 5,89 lights lamp 5.08 to signal the information Voperator that .the trunk is lstill connected to the cross-bar switches and incoming trunk; Figs. 2, 3 and 4, This signal is extinguished when the switches are disconnected from the ytrunk to advise the information operator that the trunk is free. 'I'he release of relay 582 establishes a recall interrupter circuit by associating interrupter 586 With lead 522. The rotation or" this interrupter intermittently associates an open circuit and a ground through contact 3 of relay 535, contact of relay 502, co-ntact 2 0f relay 50,5, contact 4 of relay 504, lead 522, Winding of retardation coil 50|, lead 520 and thence over 4the ring conductor through switches 404, 403, ,402 and 40|, retardation coil v303, contact 8 o f relay 302 which is operated, contact 9 of relay 2 I3 which is released, contact I0 of relay 30| released, right Winding of relay 3I3 to battery. When the information operator disconnected and relay 502 Was released, the 'rst vopen circuit from interrupter 58S causes the release of relay 3 I3 by the action of-its differential Windings. The release yof relay 3.I3 reestablishes the operating circuit for timing relay 208 from batterythrough its Winding, contact 3 of relay 20|, contact 4 of relay 285, contact 2 of relair 3I3, contact 4lv of relay vv,2I3 to ground on contact 3 of relay 2I,4 or contact 3 of relay 2I1. The release of relay 3I3 also establishes a circuit to connect interrupter 3&5 with the` timing relays which circuit may be` traced from ground through interrupter 3l5, contact I of relay 3I6, contact I' cire-lay 3i3,.contact 3 of relay 205, contact I of relay :258 to timing circuit relays. A circuit'for relay :3I2 is established from battery through its left Winding, contact 2 of relay 348, contact 4 of relay ;3I,3, Contact 8 of relay 2I-3 to ground on contact 2- of, relay-2 i4, or contact 4 of relay 2I'I. Relay 3I2 locks through its rightl Winding to ground on contact 2 of relay 2I74 or contact .4 of relay 2H. The rotation of interrupter 506 in the information operators trunk circuit after a time interval associates ground with conductor 522 through relay contacts including contact 3 of relay 5.85, contact of relay 502, contact 2 of relay 585, contact 4 of relay ,50,4 to conductor 522 Which extends through `.the winding of retardation coil 455| to the ring conductor as previously traced and through the -right winding of relay 3I3 to battery. Relay -3I3 is again unbalanced and operates. The operation of relay 3I3 opens the circuit for timing relay 208 causing this relay to again release. Since in this instance relay SIG is operated, a circuit for the timing relay will not be reestablished from (i3-volt battery 324. This operation of relay 3I3 establishes a circut for relay 3I'I which may be traced from battery through the Winding of relay 3I'I, Contact I of relay 2H, Contact I of relay 3H), contact I of relay 312, contact 4 `of relay 3| 3, contact 8 of relay 2I3, contact 2 of relay 254 to ground, or to ground through contact l4 of relay 2I'I. Relay 3i? locks to ground on con-tact 2 of relay 2I4 or contact 4 of relay 2II through contact 4 of relay 3I8. The operation of relay 3I'I open-s the holding circuit for relay 2 I 2 which extended through contact 3 of relay 2I2, contact I of relay 3I'I, Contact 2 of relay 205, contact 3 of relay 302, contact 'I of relay 228 to ground on contact Bof relay 3! I.

The responsive operations to the opening of the circuit for relay 2`i2 depend upon which of relays 2I'I or 2I4 was operated when this call Was set up by the cordless operator. Assuming `that only relay2 I'I is operated, and that the link and channel Were disconnected from the trunk, lthe release of relay 2I2 must energize apparatus for establishingcircuits for obtaining the services of a link to again connect the incoming trunk .circuit to `a cordless toll operators position. In this .case the release of relay 2I2 reestablishes the operating circuit for relay 2I3 from battery through its winding, contact 5 of relay 2I2, contact 2 of relay 205, contact 3 of relay 302, contact 1 of relay 220 to ground on contact 6 of relay 3I I. The operation of relay 2I3 opens the locking circuit -for relay 3I8 which extended through contact 8 of relay 2I3. Relay 3I8 releases and, -in so doing, opens the locking circuits for relays `3I 'I, 3I2 and 3I8 lwhich extended through contact 4 of relay 3I8. Relays-3H and 3I2 are slow to release and establish newlocking circuits through contact 4 of relay.2|3 to ground on contact 3 of relay 2|1. Therefore, at this time the only relays which areV operated in .the intertoll trunk circuit are relays 2|1, 302, 3|2 and 3|1 which remain operated, and relay 2 I 3 which was operated by the release of relay 2|2.

Link connection calling toll operator in office 200 with the cordless toll operator of this telephone oiice without waiting for a new call from this operator.` The link start circuit may be traced from ground through contact I of relay 2 |4, contact 3 of relay 2I3, contact I of relay 2I2, lead 343, winding of link start relay 6|0 to battery. The energization of relay 6|0 establishes circuits for nding an idle link control circuit, such as 601, and operates a relay, such as 6I I, for connecting the control leads between the incoming `trunk circuit and the control circuit. The operation of the link control'circuit is the same as previously described'for testing a plurality of channels entering the cordless toll positions and for energizing switches, such as 600 and .60| associated with an idle channel. The cordless operators position and the channel in this position which is seized on this recall may be the same as for the original call or may be a different cordless position and a different channel than was taken for use when the toll operator 200 called for information, as previously described.

Signaling cordless toll operator x The operators position circuit and channel apparatus is the same for all positions and thus only one is shown. The apparatus of the channel and the apparatus of the toll operators position is energized for -this automatic recall by the 'information operators outgoing trunk in the same manner as previously described, including the operation of relays,1|0, 1| I, 1|3, 103 and 104 for making the channel busy and for associating the signaling'circuits with the incoming trunk. The operation of relay 103 associates ground with conductor `620 extending through contacts I2 of switches 600 and 60|, contact 2 of relay 220,

winding of relay 2I'2 to battery for reenergizing the latter relay in the incoming intertoll trunk circuit. The position signaling circuit is energized by battery through resistances 322 and 230 in multiple through contact 2 of relay 2|2, lead 331,7contact 1 of switches 600 and 60|, contact 2 of relay 103, windings of relays 8I4, 8I5 and 8|6 to ground. Relays 8|4 and 815 are operated which establishes a circuit for relay 802. A signaling path is completed for lighting a lamp in the toll operators position and for establishingthe tone circuit as previously described. The cordless toll operator immediately challenges the calling operator at the distant toll office 200 who-,now gives the code designation and number of the Wanted party which is the code designation and number givento the distant-toll operator in ofce 200 by the information operator. The Vcordless toll operator accordingly operates her key-set for setting therregisters of a sender, such as 4|5, which in turn, operates the apparatus of a marker, such as 4I6. This marker now tests a plurality of outgoing trunks extending to an office according to the designation given by the toll operator 200. An idle trunk `to the wanted oince is found and made busy by the marker which then energizes switches, such as shown in Fig. 4, for associating thecalling incoming trunk, Figs. 2 and 3, with the outgoing trunk extending to the wanted oice. The operation of the sender and marker for completing a connection of this character is as vfully described in the aforementioned patent 2,236,246 to King et al., March 25, 1941.

In the case where the relay 2I4 was operated by the cordless toll operator for maintaining a channel locked between the position and the incoming intertoll trunk, Figs. 2 and 3, it is not necessary to again establish a link start circuit when the information operator disconnects from the information trunk shown in the left portion of Fig. 5. This link is locked by the association of groundl through contact I of relay 2|4 with v lead 333, contact3 of switch 000, winding of hold magnet 604 to battery, Winding of hold magnet 605 to battery andthrough contact 3 of switch 60|, Winding of relay i|| to battery. It will be remembered thattrunk relays 3|2, 3|3 and 3| 1 were energized when the information operator disconnected from the information trunk. The

operation of relay .SI1 opens the holding circuit for relay 2|2 which releases. The release of relay 2I2- reoperates relay 2|@ which now establishes a circuit for the channel talking relay 1|0. The circuit for relay 1IIJ may be traced from ground on contact 2 of relay 2|3, contact 2 of relay 2I2, lead 331, switches 600 and 60|, contact 2 of relay103, winding of talking relay 1I0 to battery. The apparatus of the channel and position circuit is operated as hereinbefore described. The operation of relays lSI2 and 3|1 associates battery through resistances 322 and 230 in multiple with'the signaling circuit in the cordless toll operators position for energizing relays 8|4 and 8I5. This circuit is the same as previously traced from battery associated with the resistance 322 through contact 4 of relay 3I2,`

contact 2 of relay 3|1, contact 2 of relay 2|2, which places resistance 322 in multiple with resistance 230 and extends battery through this combined resistance value over lead 331 to ground through relays 8I4, SI5 and 8|6. The operation of relays 8I4 and SI5 establishes an energizing circuit for relay 802 which, as previously described, energizes the tone relays for giving a distinctive tone to the cordless toll operator. In addition to this, a signal is given to the operator by ashing lamp 106 when the interrupter 50B of the information operators trunk is associated with the ring conductor. This ashing circuit is `the same as previously described and, it is believed, need not be retraced. The foregoing `signals are transmitted to the cordless toll operator immediately after the information operator has disconnected from the information trunk. The cordless toll operator challenges the toll operator in the distant toll oice 200 shortly after the latter operator has received the information governing the code designation and number of the wanted party from the information desk operator.

Disco'nnectzon of switches After an automatic recall by disconnection from the rinformation oflice outgoing trunk the switches connecting the incoming trunk with this l tact 9 of relay 30|. When the switches of Fig. 4 are to be held the splitting relay is operated by a key such as 121 so that ground is extended through contact of relay 'H3 thence over lead 624 to the incoming trunk circuit lead 352 and the hold magnets. The hold magnets 409., 4I0, 4H and 4i 2 are released and relay 503 in the information operators outgoing trunk is also released. This releases the apparatus of the outgoing trunk circuit since relay 504 was held operated to ground on relay 503 and relay 505 was locked through contact 2 .of relay 504. After receiving the code designation and number .of the wanted party, the cordless operator proceeds in a manner previously described for setting the position key key-set which operates the position sender 4l5 and the marker 4|6 for completing a connection to the designation office given by the calling toll operator in office 200.

It may be seen from the foregoing that a considerable saving is made in the holding time 0f toll lines by the adoption of the circuit according to the invention since with other traiiic practices known in the art time is consumed by the originating toll operator in oiiifce 200 in recalling the cordless toll operator to give her the office designation transmitted by the information operator. This time is consumed in setting up apparatus in office 200 in a similar manner to that described for the cordless operator in this office. After this apparatus has been set up ringing current is transmitted as described for again operating the apparatus of the incoming trunk, such as shown in Figs. 2 and 3. After the apparatus of the incoming trunk is again energized the cordless operator is reached by the actuation of a link in a manner previously described. In the present arrangement, according to this invention, the cordless operator is immediately reassociated with the incoming intertoll trunk from the distant ofce 290. The toll connection to the wanted party is thus completed in a minimum time period and a saving is made in the holding time of expensive toll trunks.

What is claimed is:

1. In a toll rtelephone system, an oiiice having a plurality of attending toll operators positions therein, distant oiilces having operators therein, links, incoming trunk lines from said distant olces having link actuating means and signaling means, means in an incoming trunk responsive to a call initiated by an operator in a distant office for establishing a link actuating circuit, means in a link responsive to the establishing of said actuating circuit for connecting said calling incoming trunk to an idle attending operators position, an information operators switchboard, outgoing trunks to said information switchboard, outgoing trunks to telephone stations, means in said attending operators position for controlling the connection of said incoming trunk to an outgoing trunk extending to an information operators switchboard, means for disconnecting said attending operators position from .said calling incoming trunk, means for connecting the equipment of the information operators switchboard with said outgoing trunk for transmitting information to said calling operator and for disconnecting the information equipment from said outgoing trunk, and means in said outgoing trunk responsive to said disconnection for reconnecting said calling incoming trunk and consequently the calling operator with an attending toll operators position for completing a desired telephone connection.

2. In a toll telephone system, an office having a plurality of attending toll operators positions therein, distant offices having operators therein, means for automatically connecting an incoming trunk to `one of said attending toll operators positions responsive to an inlcoming call over said trunk, an information operators switchboard, outgoing trunks to said information switchboard, means in said operators position for controlling the connection of said incoming trunk to an outgoing trunk extending to an information operators switchboard, means for disconnecting said toll position from said calling rincoming trunk, means for connecting the equip-. ment of the information switchboard with said outgoing trunk for transmitting information to the operator in said distant office lcovering a station designation and for disconnecting the information switchboard equipment from said outgoing trunk, and means in said information operators outgoing trunk circuit responsive to said disconnection for automatically adjusting the apparatus of the calling incoming trunk circuit for reassociating said incoming trunk circuit with oneof said operators positions.

3. In an automatically operable telephone ofice, incoming trunks, operators positions, links, means in an incoming trunk responsive to an incoming call over said trunk for operating `an idle link, means in Asaid link for automatically selecting an idle operators .position for connecting said incoming trunk to said position, an information operators switchboard, outgoing trunks to said switchboard, a register control device, means in said selected idle operators position for setting the registers in said control device, means in said control device responsive to 'said setting for automatically selecting an idle trunk to an information operators switchboard, means for releasing said link for disconnecting said operators position from said calling incoming trunk, means for connecting said switchboard to said idle outgoing trunk for transmitting information over said calling incoming trunk and for disconnecting said 'switchboard from said outgoing trunk, and means responsive to said disconnection for reactuating a link to connect said incoming trunk with an idle operators position.

4. In a telephone office. incoming trunks from distant offices, operators positions, means for automatically connecting an incoming trunk to one of said operators `positions `responsive to an incoming call over this trunk, an information operators switchboard, outgoing trunks to said information switchboard having pulsing devies, means in said Aoperators position for controlling the connection of said incoming trunk to one of said outgoing trunks, meansl for releasing said link for disconnecting said operators position from said calling incoming trunk, means for connecting the information switchboard equipment with said outgoing trunk for transmitting information to the operator in said distant office covering a station designation and for disconnecting the information switchboard equipment from said outgoing trunk, equipment in said outgoing trunk circuit responsive to said disconnection for associating said pulsing device with the equipment of said incoming trunk circuit, and means in said incoming trunk circuit operably responsive to pulses from said device for reconnecting the operator in the position with the calling distantoice. I

5. In a toll telephone system, an oice having a plurality of attending toll operators positions therein, distant olTlces havingoperators therein, links, incoming trunkY lines from said distant oflic'es having link actuating means and signaling means, means in anincoming trunk responsive to a call initiated by an operator in a distant oce for' establishing alink actuating circuit, means in said link responsive to the establishing of said circuit for connecting said'ca'lling incoming trunk to an idle attending operators position, kan information operators switchboard, outgoing trunks to said switchboard having pulsing devices, meansinsaid operators position for con# trolling the connection of said calling incoming trunk to one ofsaid' outgoing trunks, means in said outgoing trunk for operating an information switchboard signal, means for connecting the information switchboard equipment xvith said outgoing trunk for transmitting information to the operator in said calling office covering a station designation and for disconnecting the information operators switchboard equipment from said outgoing. trunk,'a relay in said outgoingtrunk circuit operable in response to the connection of said information switchboard equipment for transmitting a signal to the attending toll operators position and'for operating a second relay which 'is locked in Yits operated position, said first relay' being vreleased responsive to the disconnection of the information switchboard equipment from said outgoing trunk, means for releasing said link for disconnecting said attending oper ators position from said calling incoming trunk, a circuit established by the release of said rst relay through the contacts'of said second locked relay for connecting said pulsing device with the equipment of the incoming circuit, means in said incoming 'trunk circuit responsive to pulses from said pulsing devicefor adjusting said incoming trunk circuit equipment to reestablish said link actuatingcircuitfor reconnecting said incoming trunk circuith and the calling office with an attending toll operators position.

6. In atoll telephone system, an ofce having a plurality of attendingy toll operators positions i therein, distant offices having operators therein,

links, incoming trunk lines from said distant offices having link starting means and signaling means, means in an incoming trunk responsive to a call initiated by an operator in a distant cnice for establishing a link actuation circuit, means in said link responsive to the establishing of said circuit for connecting said calling incoming trunk to an idle Vattending operators position,an`infor mation operators switchboard, outgoing trunks to said switchboard havingpulsing devices, means in said operators position`v for controlling the connection lof said calling incoming trunk to one of said, outgoing trunks, means in said outgoing trunk for operating an information switchboard signal, means for connecting the information switchboard equipment with said outgoingj trunk for transmitting information to the operator in said calling oflice covering a station designation and for disconnecting the information operators switchboard equipmentl from said outgoing trunk, a relay in said outgoing trunk circuit operable in response to the connection of said information switchboard equipment for transmitting a signal operated position, said first relay being released responsive to the disconnection of the informa-'r tion switchboard equipment from said outgoing.: trunk, means for releasing said link for disconnecting said attending operators position from `said calling incoming trunk, a circuit established bythe release of said first relay through the contacts of said second locked relay for connecting said pulsing device with the equipment of the'. incoming circuit, means in said incoming trunk` circuit responsive to pulses from said pulsing device including a plurality of relays for adjusting said incoming trunk equipment to reestablish said link actuating circuit for reconnecting said incoming trunk circuit and the calling oliice with an attending toll operators position and for adjusting said incoming trunk circuit equipment for transmitting signals to said' attending operators' position for indicating the character of call incoming to said position.

'7. Ina toll telephone system, an office havin a plurality of attending toll operators positions therein, distant offices having operators therein, links, incoming vtrunk lines 'from said Vdistant oliices having link starting means and signaling means, means in an-incoming trunk responsive to a call initiated by an operator in a distant office for establishing a link actuating circuit, means in said link responsive to the establishing'of said circuit for connecting said calling incoming trunk to an idle attending operators position, an information operators switchboard, outgoing trunks to said switchboard having pulsing devices, means in said operators position for controlling the con-v 1 nection of said calling incoming trunk to one of said outgoing trunks, means in said outgoing trunk for operating an information switchboard signal, means for connecting the information switchboard equipment with said outgoing trunk for transmitting information to the operator in said calling oiice covering a station designation and for disconnecting the information operators to theattending toll operators position and for operating a second relay which is locked in its switchboard equipment from said outgoing trunk, a relay in said outgoing trunk circuit operable in response to the connection' of said information switchboard equipment for transmitting a signal to the attending toll operatorsposition and for operating a second relaywhich is locked in its operated position, said rstrelay being 'released responsive to the disconnection of the information switchboard equipment from said outgoing trunk, means for releasing said link for disconnecting said attending operators position' from said calling incoming trunk, a 'circuit established by the release of said iirst relay .through the contactsv of said second locked relay vfor connecting said pulsing device with the equipment of the incoming trunk circuit, means in said incoming trunk circuit including a relay which releases and operates responsive to impulses from said pulsing device for successively releasing certain trunk circuit relays and operating other trunk circuit relays for reestablishing such link actuating circuit to reconnect said incoming trunk circuit and the calling oice with an idle attending operators position and for establishing a signal circuit in said attending operators position for indicating the character of call incoming to said position.

8. In a telephone system, a telephone oflice, incoming trunks, outgoing trunks, switches for interconnecting said incoming and said outgoingY trunks, a plurality of call completing operators positions, means responsive to` an incoming call for selecting any idle one of said positions for connecting the calling incoming trunk therewith,

Images