US1808574A

US1808574A - Telephone system

Info

Publication number: US1808574A
Application number: US147418A
Authority: US
Inventors: Rodney G Richardson
Original assignee: Automatic Electric Inc
Current assignee: Automatic Electric Inc
Priority date: 1926-11-10
Filing date: 1926-11-10
Publication date: 1931-06-02
Anticipated expiration: 1948-06-02

Description

June 2, 1931. R. ca. RlcHAosoN TELEPHONE SYSTEM Original Filed Nov. 10, 1926 5 Sheets-Sheet l r o F n F goo Imam. Endue EEiuhardsun HIT.

June 2, 1931.

R. G. RICHARDSON TELEPHONE SYSTEM Original Filed Nov. 10, 1926 3 Sheets-Sheet 2 Q m3 s3 Imreu r Hndns EEz'chardgm my TQ TQ R June 2, 1931. R. G. RICHARDSON TELEPHONE SYSTEM Original Filed Nov. 10, 1926 3 Sheets-Sheet 3 11mm? Ewing; EHiphardsufl mm @1 Patented June 2, 1931 UNITED T TES RODNEY G. nrcHARDsoN; or cHIcAe ILLINoIs; AssIGN oRf'ro Anroivmrro'nLncrnIc 1 l. mq or CHICAGO, rumors, A coRronATroN or DELAWARE TELEPHONE SYSTEM Application filed November 10,'1s2e-, Serial No. 147,448. Renewed August 11, 1930."

This invention relates to telephone systems in general, but is more particularly concerned with automatic telephone systems in which register senders or directors are used to registercalled numbers and route the calls to their destinations. 4

Considering, for example, multi-oflice telephone system with a six digit numbering system employing directors of. the ordinary or 1 more common type, when a call is initiated, an idle one of a group of directors is taken into use by means ofa non-numericaljselecting switch, and the called number, as dialed by the callingsubscriber is registered thereon.

is The first two digits'or letters of the number, designating the oflice serving the called subscriber, are registered on the office register of the director, while the remainingdigits of the'number, designating the line in that office,

29 are registered on the digit registers of the director, The director, in turn, sends out an office code to route the call to the oilice serving the called subscriber and then sends the line designating digits as registered on the digit 2- registers. Upon completion of these operations, the director releases and may then be taken into use to extend another connection.

The same operations take place when an operator, such as the information operator, long so distance operator, etc., whose call number comprises no more than two digits, is called, except that in this casenone of the digit, registers are used.

The object of this invention is the provision as of a separate oificedirector, comprising an ordinary oflice register and a translating and sending mechanism for registering the oflice designation ofa called number andtransmittingthe office code, and a separate line di- 7 10 rector com risin the ordinar di it re isters and also a sending mechanism for registering and retransmitting the line designating digits. t According to the invention, a group of di- 4 rectors of each type is made accessible to separate director selectors,'and in extending a connection, an idle oneof each type of director is taken into use only for the length of time needed to perform its operations. More specifically, in a system employing separate office directors and line directorsas' intro duced by this invention, when-a call is initiated, an idle one of a group of oflice directors is taken into use by means of an office director selector and the ofiice designation as dialed by the calling subscriber is registeredthere on. Before the last digit or letter of the oflice designation has been registered, an idle'one of a group of line directors is taken into use by means of a line director selector. If: the call is for one of the special operators,.whose call number comprises no more than two-digits or letters, the line director is released again as soon as the second digit or .letteris registered. Thus,-the line director is held only for the length oftime necessary to dial one digit, if the type of call issuch as notto require a'line director; If the call is forua regular subscriber, the linev director. taken into use is not released, and the line designating digits are registered on the digit-reg isters ofthe' line director. At the same time that the line designating digits are; being registered, the office director transmits ;the oflice code, and upon completion thereof, the office director is released :and :may then be taken into use to'extend another call. Thus, the office director is held only for the length of time necessary to register the oflice designating digits and transmit the oflice'code. The line director transmits the line designat ing digits as registered, at the completiono of which it is released and may then be taken into use to extend another call. 1 1

According to the'above description, it is evident that the holding time of the oflice di rector is considerably less than thejzholding time of an ordinary director, sinceit-isreleased immediately following, the transmis? sion of the olfic'e code. Also, the holding'time of the line, director .is less than the holding timeof the ordinary dlI6Ci3OI,'S-l1lC6 it is not taken into use until just before the last'digit or letter of the office designation is registered, and therefore is not held during the usual pause that follows the removal of the receiver and before the subscriber commences dialing. This interval occasionally is very long for reasons such as a subscriber failing to look up the. telephone number until after he has: re

mine the type of call. As a result,

moved his receiver. Furthermore, no line director is used ina call to a special operator, except for the instant necessary to deteronly the minimum'amount of director equipment is held in use at any one ti1ne.- Obviously then, by usingseparateiofiice directors and separate line directors as introduced by this invention, considerably less director equipment needed in any given exchange systemthan would be needed if'director's of the ordinary type were used.

Attention is also called to the fact that in any telephone system, in spite of all that is done to prevent it, grounded lines, short circnite'd lines; etcx; occur and temporarily hold equipment out'o-i servie'e,such equipment including directors when they are used. In a system using separate office directors and separate line: directors 'ac c'o-rding 'to the present invention, only the ofiice directors, which are smaller and less expensive than ordinary directors; can be temporarily heid out o'f's'e-rw ice by reason of a lmebernggrounded or short cireuited-z Thusthe amount of added director" equipment ordinarily necessary to meet such contin'gen'cles' s reduced: Theinv'entiom'its features as outlined above and'itso'peration, will @be described in detail with the aid of the annexed drawings, comprising 1 Figs.- 1 3; .in'clusive*,- which show *loy means of the usual schematic circuit diagrams tho'new and inr-prove'd' directors and the principalapparatus associated therewith: To understand the relation of the drawings,

Fig; 1=shculi be la ced above Figs. '2" and 3 with the= corresponding lines in I lignment.

' in 'thisrparticular' einbodyment of the invendescriptions will berferrd to as compris iiigatwo digits;

IirFig. 1 of the drawings;'thetrunkiine comprising conductors 101, 102', and'lo is shown with its" associated "trunk relay group TRG, its individualoflice directorselector ODS, and its individual line'dire'cto'r selec tor LDS." This trunk is'one of aplurality of trunks'similarly' equipped which are acoes's'ibl'e in the'ba'nks of preseiectors or sub scribers" individual lineswitches, and-which terminate in automatic switchessuch as, for

example, first selectors of the S'trowger ve'itic'al androtar'y'typ'er p In the banks of the office director seie'ctor ODS, as well a's 1n the banks Mother-similar oflice director selectors multiply connected with the banks of the oflice director selector ODS, access is had to a group of office directors, one of which is shown in Fig. 2. In the banks of the line director selector LDS, as well as in the banks of other Similar line director selectors multiply connected with the banks of the line director selector LDS, access is had to a group of line directors, one of which is shownin'Fig. Mechanically, and in principle ofop'e'r'ation, the oflioe director selector ODS and the line director selector LDS are of the well known rotary type of non-numerical selecting switch.

It is understood, that in a larger system,

a seven digit systemfor instance,-th'e otfiee director selector becomes a numerical selecting switch u'ponwhich the first'digit'of the office designation isdialecl, as is} disclosed-in the copending application ofR. Richardson, et a].., Serial No. 547,866, filed M'ar'ch29,

The ofiice directcr shown'in Fig! 2 e611]- prises essentially two motion office regis 'ter' OR upon which the oflice designating roper'sequenee, the'constantl'y rotating in V ter1l-'up"te'i'-' I for operating the-1sender switcll SS. a'ndva'rio'us co'iitrolhng-frelaysu 'It should he mentionedthat in smaller system satires in a fivedigit system wherein only one'digit designates the ofli'ce, to which the principle of the invention is, also ap'p'licable, the once register ofthe office director would belonly a single motion switch. a i

The line director shown in comprises essentiallyfour digit registe siupcn which the line designating digits"are're'gistered,- a sequence switch S for 'controllingfthejopera tum of the digit registers, a'sender switch SS for sending-the line designating digits,;a sequence switch S for controlling"'thefseridiiig of the line desi natingdigits in their proper sequence, the constantly retatingtnterrupter I for operating the sendersw'itoh SS and' variouscontrollingrela s:

The mechanical construction ofthe various parts of the director is like that o ffcor're sp'o'nding parts of the ordinary" director lawman the'art and therefore'ne'edfnot he further described. J I 1 With this general. description ofthefe'atureso'f the' inventionand'the results to he ati tair'ie'd in mind, a further understanding and appreciation of the invention may be gainedfrom a detailed description of the operation of the apparatus nsed'in settingup the vari ou's possible 'kir'idsof connections. For this purpose it'will first'lieassiiriied tliitt seine subscriber, served'by the exchange in which the apparatus shown in the drawings is located, desires connection with some other subscriber in the system. To initiate the call, the callingsubscriber removes his receiver and then dials the digits of the'directory number of the subscriber with whichhe wishes to converse. 7

Responsive to the removal of the receiver at the callin station, the calling subscribers individual hneswitch operates to select an idle trunk. It may be assumed that the trunk selected is the one comprising conductors 101, 102, and 103. lVhen this trunk is seized, a circuit is established for the line relay of trunk relay group TRG, which circuit in eludes the trunk conductors 101 and 103 and the bridge at the calling station in series. Relay 110 operates and closes a circuit for release relay I 111 at armature 115. Relay 111 energizes and grounds the release conductor 102 at armature 109, closes a circuit for the switchin relay 141 of the ofiice director selector OD at armature 117, and at armature 118 closes the stepping circuit for magnet 142, at the same time short circuiting switching relay 141, providing the wipers of the office direct-or selector ODS are in engagementwith the bank contacts associated with a lousy director, in which case ground potential. will be present on the bank contact engaged by test wiper 154. Magnet 142 then operates in a buzzer-like manner to advance the wipers 153-157, inclusive, until an idle director is reached, which may be as sumed to be the one accessible by way of conductor 163-107 tor is connected with, its idle condition being indicated by the absence of ground on conduct'or 164 connected to the bank contact now engaged by wiper154, magnet 142 ceases to operate and the short circuit is removed from switching relay 141. Switching relay 141 then operates and performs the following circuit changes: at armature 143 the impulsing circuit over which the office designating digits are to be sent to the othce register is prepared. At armature 1'44 ground potential is placed on the test contact to which conductor164 is connected and on the test con tacts of other ofiice director selectors multiply connected therewith to mark the ofiice director in question busy, at the same time closing a circuit for release relay 222 of the oiiice director. Relay222 operates and opens points in the release circuits of release magnets 218 and 207 at armature 228 and opens a point in the return stepping circuit of magnet'209 at armature 227. At armature 145 of relay 141 a start circuit is prepared for line director selector LDS as will be described presently. At armatures146 and 147 a bridge is closed across trunk conductors 101 and 103, this

bridge including springs

129 and 132 controlled by armatures-129 and 132,

inclusive. lVhcn this direc selector LDS to battery.

respectively, armatures. .146 and-147,wipcrs 156 and 157,

conductors

166 and 167, shunt springs 229, and impulsing springs 239. By

reason of this bridge across eond-uctors101 and 103, the line relayand rel'easerelay of a the selector switch terminating these conductors are operated ,111 the usual manner, to prepare the selector for operatlonf Responsive to the dialing of the first digit of thecalled number, line relay, 110,0perates tery. Vertical magnet 216 operates andraises the wipers 241-245, inclusive, of. the

office register OR opposite the level o f bank contacts corresponding to the digit dialed. Series relay 201 operates in series with magnet 216, and due to its slow acting characteristic maintains its armature 203 operated during the transmission of this seriesofim pulses, closing a circuit for relay 202. Relay 202 operates and prepares a circuit described later. At the termination of this series of impulses, relay 201 dcenergizes and breaks the circuit of relay 202. .Relay 202is slowacting, however, and it follows that a circuit is closed momentarily for stepping magnet 206 of sequence switch S, this circuit includ:'

ing armature 204'and armature 203.. Magnet 206 operates and steps the

switch wipers

213, 214, and 215 in engagement with the next set of bank contacts.- lViper 214, on moving to its second position, shifts the in.- coming in'ipulsing circuit from the. vertical magnet ofthe oflice register to tlierotary magnet, so as to prepare for the receipt of the next series of impulses.

E lie operation of the sequence switch- 5) also brings about the selection of an idle. line director, andfor convenience this operation will now be explained. The engagen'ient of wiper 213 with bank contact 262 closes a circuit which may be tracedirom ground through resistance 220, bank contact1262,

wiper 213, conductor 165,;wiper155, arma;

ing-transfer'relay 113, through thewinding of start relay 170 of-the line director Due to the resistance 220 in this circuit, the current flow is insufiicientto cause the operation of relay 113. Relay 170 operates, however, and at armature 177 closes a circuit for switching relay 171, and at armature178 clo'es an op; erating circuit for stepping magnet 172, at the same time short-circuiting relay171 pro: viding the wipers of line director selector LDS are standing on the bank contacts associated' with a busy linedirector in which I case ground-potentialwill be present on the ing'ci'rc-uitchangesz at armature 173' the 1mbank contact engaged by test wviper 184:.

Stepping magnet 172 then operates in a "buzzer-like manner tda'dvanoe theswitch wipers 183-18-6, inclusive, until an idleline director is reached: When an idle line dir'ectoris reached, for example, the one accessible by way of conductors 193496, inclusive, its idl e'c'ol'ldition being indicated by the'a'bsenc'e of'ground potential on conductor 194 connected to the bank contact now engaged by wiper 184,- the operation of stepping magnet 172 ceases and the short circuit around relay 171 is removed. Switching relay 171 operates and performs the followhas been transmitted by the oilice director as willbe described fully presently. The application of groundpotential to conductor 19a also closes a circuit for release relay"322-,

' and the resting contact.

which operates and opens points in the re- .turn-to-normal clrcuit of sequence switch S and-in the release circuit of the digit registers,

at alinatures 327 and 328, respectively; The engagement of armature 340 and its working contact at this time closes a circuit for re lay 324:, this circuit including armature 320 The function of the operation of relay 324 will be fully de scribed hereinafter. v

Responsive to the dialing of the next digit, which in this particular case is the last oihce designating digit, line relay 110 again responds and sends a corresponding number of ground'im'pulses over the same path as previously traced to wiper 214: which now is in-enga9jeme1'1t with contact 262", through the i'otaiyinagznet 217 to battery. Rotary mag;- net 217 operates responsive theretdand' rotate's' the Wipers 2l1-2l5 into engagement with the" corresponding set of bank con tacts of the selected level, which may be assumed to'be contacts 251255, inclusive.

Relay 201 again operates this time in series with rotary magnet 217 and again closes a circuit for relay 202. Relay 202 energizes as before. At the termination ofthis series of impulses, relay 201 deenerg'izes and again closes'a circuit for the stepping magnet 206,

which operates and moves the

switch wipers

213, 214, and 215 into engagement with the third'set of bank contacts. The advance of wiper 215 to its third position starts the of- -fice director to send out the oflice code, but

mom's-74 further explanation of this operation willbe deferred pending the explanation of the The increase in current flow through the lower winding of relay 113, Fig. 1, is sufficient to causethe operation of relay 113. This relay, in operating, closes alocking circuit for itself in series with its lower winding at armature 125, this locking circuit eXtendingto release conductor 102'byway of armature 120 and the resting contact; atthe same time, springs'125rare separated; At armature 126 and the workingcontactthe im ala ing'" path is extended to the line director shown in Fig. 3. At the same mm, by the separation of springs 126, theimpulsing path extending to the office director shown in Fig. 2' is disconnected. I circui. is prepared for sending transfer relay 114- to be described presently. I

For tnesake of example, the oflicecode to be sent to route the call to the oflice serving the calling subscriber is assumed to be 79.

At armature 127 a At the distributing frame DF, the terminal connected to bankcontact' 251 is cross" conne'eted to the right hand terminal No. 7. The tern'lii'ialconnected to bank contact 252 is cross connected tothe right-hand terminal No. 9; and since there are no more code digits to be sent, the terminal connected to bank contact 253 is cross connected .to'the'righthand terminal No. 12, this being'the switcln ing-through terminal. By the engagement of wiper 215 with the third contact in its bank, ground potential is connected to the brush of the constantly rotating interrupter I. The circuit of steppingmagnet 235 of thesender switch SS is now intermittently opened and closed at-the predetermined rate at which'im'pulses are to be sent to the auto matic switches. Responsive to the first operation of magnet 235. wipers 236 and 237 are moved'into engagement with=the lir'st'set of bank contacts in their respectivebanks. A circuit'is-then established for relay 223, this circuit including wiper 237 and'its first bank contact. Relay 223 operates and opens" the next operation of magnet 235,-the bridge across the outgoing trunk conductors 101" and 103i is openedatimpulsing springs 239, and:

wipers 236 and 237 are moved into engagement with the next set of contacts in their respective banks. Magnet 235 continues'to operate in this manner, each time opening the bridge acrozs the outgoing conductors at springs 239, until wiper 236 engages the bank contact connected to the right-hand terminal No. 7 of distributing frame DF. When wiper 236 reaches this contact, a circuit is closed which may be traced from ground by wayof wiper 212 of sequence switch S, and its'first bank contact, wiper 241, bank con tact 251, terminal No. 7 wiper 236, winding of stop relay 224 to battery. Relay 224 operates and places a shunt around-impulsing contacts 239 at armature 232;"closes'a holding circuit for itself at armature 233,

at the same time opening the energizing cir-' cuit of magnet 209; and closes selfinterrupting circuit for magnet 235 at armature 234 and the working contact. Magnet 235 now operates in a buzzer-like manner to step" the wlpers 236 and 237 to their normal pos1- tion (the position shown), whereupon the self-interruptingcircuit is opened, wiper 237 engaging its ungrounded normal contacts Wiper 237, in engaging its ungrounded normal contact, also opens the clrcuit of relay 223. Furthermore, magnet 209, in deenergizing, moves the wipers 211 and-212 intoengagement with the-next set of bankcontacts.

vResponsive to the seveninterruptions in the bridge across conductors 101 and 103, the selector switch terminating these conductors operates in the, well known manner to extend the connection to the next switch.

Relay 223, in restoring, opens the holding circuit of relay 224 at armature 231, and also closes a normal shunt around impulsing springs 239 at armature 229 and the resting contact. By reason of the slow acting characteristics of both relays 223 and 224, suflicient time is allowed for the operated selector to perform its selecting operation and for the succeeding switch to prepare itselfto receive the next series of impulses.

contact, and stop relay 224 operates whenwiper 236' engages the contact connected to terminal N 0. 9 on the distributing frame DF- to stop the sending of impulses by shunting theimpulsing contacts 239 at armature 232.

The circuit for operatingstoprelay 224 this time includes wiper 212now in engagement After the'elapse of this interval, relay 224 deener-. gizes and again connects the. int erruptersltowith its second bank contact, wiper 242, bank contact 252, and terminal No. 9. Relay 224, on-energizing, locks itself, closes a circuit for returning switch SS to normal, and opens the circuit ofmagnet 2090f the sequence switch S. Magnet 209 accordingly deenergizes and moves the wipers 211 and 212 into engagementwith the third set of bankcont-acts.

Responsive to the nine interruptions in the bridge across conductors 101 and 103, the selector switch, to which the connection was extended by the precedingly operated switch, operates, and further extends the con-- nection via a repeater to the .oflice servingv the called subscriber. 1

The office director has now completed its function ofsending the olfice codeand-sois released and restored to normal. T-heoperat-ions performed in connection with release and restoration of the office-director will now be described. When wiper 212'is moved into engagement with the third contact in its associated bank, a circuit is closed which may be traced from ground byway of wiper 212 and'its third bank contact, wiper 243', bank contact 253,'right-hand terminal No. 12, conductor 163, wiper153, armature 143, armature 127, springs 130, controlled by armature 130, through the winding of sendingtransfer relay 114 tobattery. Relay 114 operates and performs the following circuit.

changes at

armatures

129 and 132 the bridge including impulsing springs 339 and conductors'195 and 196 is substituted for the bridge including impulsing springs 239 and-1' conductors'166 and 167, the latterlbridge be ingdisconnected by the opening of springs 129 and 132'. At armatureY131-fthe circuit of switchingrelay141 of oflice' director selector ODS is opened, causing this relay to deenergize and release its armatures; At 'ar mature 128 a point in the steppingcircuit of magnet 142 is opened to prevent: its operating again before the present call is termi nated. At armature 130 relay-114 closes a holding circuit for itselfto release conductor 102, the circuit including armature 120 and the resting contact. A i

Relay 141, in releasing its armatures, re stores the office director selector ODS to its normal condition, the wipers remaining in position on the previously selected contacts.

When relay 141 falls'back, it disconnects ground potential from release conductor 164, thereby marking the office director idle and opening the-circuit of release relay 222. Relay 222 deenergizes and by restoring its armatures to normal, closes the return stepping circuit of magnet 209 and closes the circuit. forrelease magnets 207 and 218, ofinormal' springs 275 and 219 havingclosed upon the; first step of switch S and-office. register'OR, respectively. Magnets 209, 207, and 218 then operate and restore the. ofiice director to normal. i

Q Atthispoint attention is directed to a particularfeature of the above operations. :In

the ordinary director comprising both-an, ofiice register and digit registers, and one 1 sequence vswltch for controlling the-sending of theldigits-iof the olficecode .andithe line designating digits, when the office code that.

switch S iniits next normal step following the sending ofEthe'last office code digit, re

gardless Of 'WliElCll contact in its bank it is then moved to. This is accomplished by pro viding the switching-throughterminal No. 12 on the distributing fllIfiB'DF to which theQbankcontact succeeding the one that de terminedthelast digit of the code is connected. For instance, in the above described connection, only two code digits I weresent,

and ground potential was appliedto impu'ls- 7 ing conductor-1:63 to initiatethe release of the ofiioe director and the sending operation of-the line director by way ofwiper 212 in engagement with its third bank contact,

I wiper243, contact 253, and terminal No.12,

()bviously, if the anaxirnum numberof code digits are-sent, inthis case f0ur, ground potential is applied to conductor 163 to initiate thesaid operationsjbyway of wiper 21 2 and the fifth contact directly.

Usually, in setting up a connection, the

calling subscriber dials the digits of the called number, onedigita'fter another, as

quickly as is conveniently-possible. *Tlius;

the registration of: the line-designating digits is taking place while the-ofiice director sends outtheoifice codeas just described. The operations which take place in the line director will now be-descri-bed. It will be recalled thatthe impulsing path was transferred to the "line director bythe operation of relay 113immediate1y ai ter'theregistration of the second digit.

fen-

. Responsive to the third'digit dialed by the calling subscriber, line relay 110 operates and sends a corresponding number of ground 1111- pulses-overthe path by way of-resting contact and armature 11 6, working contact and armature 126, working contact andarrnature 17 3, wiper 183,1:con'ductor .193, through the winding of series relay 301, Wiper 31 3-.of

sequence switch S bank contact 3.81, through and armature 303 closes a circuitforrelay 302. Belay, 302 operates and preparesa circuit for stepping magnet 306 atparmatnre 304. At the termination of thisSer-ies of impulses, relay 301 deenergizesand opens thecircuit of relay 302. Relay .302 is slowacting, however, soacircuitis momentarily closed for stepping :rnagnet 2306-. Magnet 306 operates andflsets the .switch1wipen313 into engagement with, bank contact 382. Wiper 3133., on moving into engagementwith bank contact .382, shifts the incoming impulsing circuit fronrregiste-r magnet 3'51 to-register magnet 352, so as to prepare for the receipt of the next series of impulses, The remainingthree digits of the called number, as dialedby the calling subscriber, are then registered on the other three registers,

[

wipers

342, 343, and 344 being positioned. on

the contact in their respective banks corre sponding, to the three digits, respectively.

WViper'313 of switch S itawill be understood,

is advanced one step after each series of impulses, so as to associate the iinpulsin-g circuit withthe operating-magnets of the registers successively. 7

The starting of the sending otthe line designatingvdigits is governed by the start relay. 321. The upper winding of. thismelay is initially includediin the bridge which as will be recalled is placedacross the trunk :conductors1101, and 103 after the oflice code has been sent by the oflice director, which, nsually takes place some time after one :or m re at the line designating digits hZLVBbQQII registered depending on the rapidity with which the calling subscriber. dials these digits. As soon as the second bridge is placed across. the-trunk conductors 101' and 10,3, relay 321 operates and closes .a lockingcircuiit for i-tselzfitothe: grounded conductor1194 at armature atarmature 325 'shortcircu'i'ts its :npperwvinding, 5111015313 armature 320-places groundgpd tent-ial on the brush of the, constantlymotating interrupter-I, at the same timewopening' the circuit-I of stop relay 324, p:rovided-,-,at least one digithaszbeen registered. Relayf324ade energizes va :short time afterits circuit is opened, allowing time for: the selecting opera-- tion of the selector operated bythe last. o ifice code digit, anduat, armature 334 and the resting .contact connects the interrupter 11 to stepping, magnet 335. Interrupter l' is now efiective to intermittently open and close the circuit of stepping magnet 335 of senderswitch 878?. The operation ot the. sender switch .SShand the controllingzrelays$23iand 324 is identical with the operation of'sender' switch SSand controlling relays 223and 224',

$5 tacts previously selected, at the :same time so a; description of the operation thereof need not be repeated. .Thejsender switch SS? operates to send out the four digits registered onthe digit registers, the order in which the digits. are sent being controlledby the sequence switch S the operation of which is the same. as the operation of sequence switchSC i i a It should be mentioned that in this line director the same method for preventing the sending operation from getting ahead of the registration of the digits as dialed is employed as has been used in other directors. "lhis method, as shown, consists in providing multiple circuitsincluding each of the register wipers and theirrespective normal contacts for .holding the stop relay 32 i energized in case the sequence switch is in position to cause the sending of a. digit which digit is not yet registered, that is, the register wiper corresponding to that digit is still in normal position- Relay 324 is held, then, until the neXt digit is registeredand being slow-acting, delays the starting of the sending switch an interval to insure against the sending switch overtaking the register wiper.

-After the sending of the final digit, se-

quence switch S operates and advances wiper 312 into engagement with bank contact 380 which initiates the release and restoration of the line director to normal as follows: the engagement of wiper 312 with bank contact 380 closes a circuit, which may be traced from ground by way of wiper 312, bank contact 380, conductor 193, wiper 183, armature 173,

, armature 126 and'theworking Contact, ar-

connected to trunk conductors 101' and 103,

mature 116 and the working contact, normally closed springsz121, through the winding of switching relay 112 to battery, Switching relay- 112' operates to perform the following circuit changes: at armature-121, relay 1'12. closes a locking circuit for itself to release conductor 102. At armatures. 122 and 123 additional points in the circuit of relays 141.

and 1 12 are opened. At armature 120 the holding circuits for

relays

113, 170, and 114 are opened, causing these relays to restore their armatures to normal. At armatures 119 and 124 trunk conductors 101 and 103 are respectively, after which relays 110 and 111 deenergize and 'restoretheir. armatures to normal. c i

Relay 170, in releasing its armatures, opens the stepping circuit for magnet 17 2 and opens the'circuit of switch relay 171. Relay 171 in releasing its armatures, restores the line director selector LDS to its normal condition, the wipers. remaining in position on the confreeing the line director by removing ground potential from conductor ;194.- This also opens the circuit 'of-the release relay 322. Relay 322, in ldeenergizing, closes the self interruptinglcircuit for stepping magnet 309- which the connection has been extended are operated. in the well known manner to extend the connection to a succeeding switch, the last switch operating responsive to the last two digits to extend the connection to the called line, signal the called subscriber, and finally complete the connection when the called subscriber answers.- i u I .At the termination of the conversation, both subscribers replace their receivers. The

replacement ofthe receiver by the calling subscriber initiates the release of the operatedautomatic switches-in the usual and well understood manner. conductor 102 opens the holding circ'uitfor switching'relay 112. Relay 112 then deen ergizes and restores its armatures to normal.

, According to this invention, a line director,

which is seized after one of the digits of a Removal of ground from 7 called number isdialed,is releasedagainas soonas it is determined thatthe call is for g a special operator whose call number consists of only one or two dlglts, therefore not requiring the l1ne d1rector.. The manner in which this is accomplished will now be dc scribed. For this-purpose it will be assumed that a calling subscriber. wishes connection with one of the special operators whose directory call number comprises onlytwo' digits. Responsive to the removal of the receiver at thecalling station, the subscribers individual line switch again operates to seize a trunk line, which will again be assumed to be the trunk line comprising conductors 101' to 103. Line relay 110, and release relay 111 again operate, and as describedcause the office director selector ODS to select and connect with an idle ofiice di-rector, which again will be assumed to be the ofiice director shown in Fig.2. .The two digits of the called number as dialed by'the calling subscriber.

are again registered, on the ofiice register OR by the operation of the vertical and rotary magnets .by positioning the wipers 241-245 into engagement with the corresponding set of bank contacts,which will be assumed to be bank contacts 251 to 255. Again the line director. selector is operated afterthe dialingof the first digitto select an idle line director. The bank contact 255, 'as well as the corresponding bank contacts of all other-- sets corresponding to the number ofother special'operators, is cross connected to terminal: No 11 on the distributing frame DF which is connected by way of normally closed contacts 225 to the line director release relay 221.: At the termination of the dialing ofthe second digit of the called number, relay 201,:l1avi-ng operated in series with rotary magnet 217, deenergizes, and as previouslydescribed closes acircuit for stepping magnet 206, and in this case-also closes a circuit which may be traced from ground byway ofxarmature 203 and the resting contact, wiper2 i5, bank contact 255, terminal No. 11,springs 225 through the winding of relay 2211to battery. Relay 221 operates and closes a' locking circuit for itself at armature 225 and the working contact, at the same time opening .its initial energizing circuit by separating springs 225, and at armature226 disconnects direct ground'potential from the resting contact of armature 205, the purpose of which will be described presently.- The deenergization of relay 201 also opens'the circuit of relay 202 which shortly thereafter 7 deenergizes and releasesits armatures.

y Referringto the description'of thepreviously described connection, it will be remembered thatrelay 11 8 of the trunkrelay group TRG. was operated afterthe dialing of the second digit due to an increased current flow in itslower windings by the connection of direct ground potential to conductor 163 when armature 205 engaged its resting contact. In the. presentconnectionthe circuit of the lower winding of relay 113 in series with relay 170 of the line director selector is opened as soon as armature205 disengages itsworking contact, since relay 221 is'now energized, Thus relay 113. is not energized, and furthermore, relayxl'ZO is deenergized. Relay 17.0 releases its armatures and 'opens the circuit =of switching relay 171 which in turn deenergizes'a-nd restores 1ts-armatures to normal, thereby releasing theline director that was taken into use after the dia ling'of the first digit.

As-"soon. as the two digits of the called numberare registered, the sender switch SS again operates to transmit the proper code to route the connection to the desiredspecial operator. Aswsoonas the oifice code hasbeen sent,.which in this casehas been assumed. to be thethree digits five, two, and three, as indi-' catcd bythe cross connections on the distributing frame DF, a circuitiis closed which may: be tIflCGdIIFOlH ground by waylof wiper 212, bankfcontact 280, wiper 244, bank conta:ct-,.25 1,-.switching through terminal No. 12, conductor 163, wiper 153, armature 143, Closed-springs 126, armature 116 and the working contact,c losed springs 121, through the winding of switching relay 112 to battery. ;Relay. 112-operates its .armatures,

closes a-locking circu-itfor itself and connects conductors I 101.;and1103 to conductors 101 and103, respectively, as before, and this time opening the circuit of relayl tl (relay 11-4 being deene-rgized) causing the restoration-of the office director selector ODS andzthe release of the ofiice ,director as previously described.

This completes the description of the i ea tures and operation of the invention. What 2. In a telephone system, an oifice director comprising registering and sendingmechanisni, a line director commontosaid o'flice director and other similar ofiice. directors, said line director also comprising registering and sending mechanism, automatic switches controlled by the office director-to trunk a calling line to the oflice containing the called line, and other automatic switches the connection. .7 V 3. In a telephone system, office directors,

line directors, means responsive to .a;call'.

for connecting the callinglinetoan idle ofi'ice director, and means .responsivextothe first registerlng operation in the selected of fice'director for testing said llne directorsand for selecting an idle line director.

4. In a telephone system, a callangll1ne,two classes of called lines, automaticsw-ltches tor register sender to control the switches .in-

volved in a connection to-a line intheother class. 7 v I 5. In a multi-ofiice telephone system,

switches for extending a calling line in 1 one ofiice to a second ofiice, other switchesfor connecting theextended calling line to a. called controlled by the line director to complete its line, and two separate register senders inthe first 'oflice' for controllingfthe two series of switches, respectively. 7 I

6. In a telephone system, a trunk line, of-

fice directors for registering one pa-rt of called numbers, line directors for registering another part of called numbers, and separate.

means for associating an idle 'oflice director and an idle line director, respectively with' said trunk line.

7 In a telephone system, an -.oflicedirector' comprising a register, a translaten'and a sender, a line director comprising a register, and a'sender, and means tor sutil zing'both said directors to control-the establishmentof a connection between a callingsubs'cribers station and a called subscribers station;

8. In a telephone system, an office directorcomprising a register, a translator, and a'sender, a line director comprising a register and a sender, means for utilizing both said directors to control the establishment of a connection betweena calling subscribers station and a called subsci'ib'ers station, and for utilizing only the office director to control the establishment of a connection between a callingsubscribers station andian operators position.

9. In a telephone system,'an oifice director, a line director, means for registering two suecessive parts of a called number on said of fice director and said line director, respectiVely, a sender in each director, and means responsive to the completion of the sending operation of said office director for starting the;

sending operation ofsaid line director.

1 10. In a telephone system, a calling line, an

oflice director, a line director, means for successively associating said directors with said line to register two successiveparts of a called number on said directors, respectively,

means responsive to the completion of the. sending operation of said ofiice director torstarting the sending operation of said line director and for releasing said oilice director.

11. In a telephone system, a trunk, a first register for registering one part of a subscribers number, a second register for registering another part of said subscribers number, means individual to said trunk for associating said first register with said trunk, and additional means individual to said trunk for associating said second register with said trunk.

12. In a telephone system, a trunk, a register for registering one part or a subscribers number, a second register for registering another part of said subscribers number, means for associating said first register with said trunk line operable responsive to the initiation of a call over said trunk line,

means for associating said second register with said trunk line, andmeans-in said first register for controllingthe operation of said last means.

13. In a telephone system, first director, a second director, means operable responsive to the initiation of a call over said trunk line for associating said first director with said trunk line, means for sending digits of a called number to said first director, and means operable after a digit has rector wi h said trunk line.

been sent for associating said second di- 14. In a telephone system, a trunk line,'a first director, a second director, means operable responsive to the initiation of'a call over said trunk line for associating said first director with said trunk line, means for sending digits of a called numberto said first p of said d1rectors, and meansresponsiveto an I directors.

first director,means operable after a digit has been sent for associating said second-director with said trunk line, and means operable are; or a predetermined number of digitshave; bwn sent to said first director foricausing the remaining digits of the called number to bej sent to said second director.

15. In a telephone system, a trunk line, a I i first director, a second director, nieansopen able responsive to the initiation of a call" over said trunk line for associating said first director with said trunk line, means for send ing digits of a called number to said first director, and means operable after a digit hasbeen'sent for associating said second director with said trunk line,'and means operv 16..In a telephone system, two directors, 7

means responsive to the initiation of a call' for. seizing one of saiddirecltors, and means responsive to'an actuatioirofthe calling sub;

scri-bers calling device but independent of the value of the-digit 'calle-d'for seizing th'e second of-said'ld-irectorsb 17. In a telephone system, two directors,

-means responsive to the initiation of a call forseizing one of said directors, and means I J responsive to an actuatio'niofthe dtl ling'sub scribers call ng device for seizingathe second other-actuation of saidcalling device for'releasing the second director,

18. In a telephonev system, two directors, a

calling line, means for successively associating said" directors WV1th*- said calling line,

means for marking each director busy responsive to its assoc at on with said calling line, andrmeans for registering one part-of the called number; only on f'one director andanother part oi? the called number only on the other director: I ii .19. In a-telephone system, two groupsvof 3 directors, a calling line,two hunting switches for successively associating an idle director of each group with said calling line, and means for registering one part of the 'calledfi part of the called number on the other of'the 20. In a telephone system, a first director, a second' director, means responsive tothe initiation of a call. for seizing said first di- Y rect or,'means for sendingdigits of a'called' number to said first directorto be'regis'tered' number on one of the directors and another- V f thereon, means operable after one digit is sent for seizing said second director, and means operable after a predetermined number of digits have been sent-to said first director f r 'cans'ing the remaining digits of the called number to be sent to said second director and or for causing said, first director to transmit digits. to extend the call.

'7 Q1. InaItelephone system, a first director,

; af secondndirector, means responsive to the initiation of acall for seizing said first director, means for sending digits of a called I number to said first directorto be registered thereon, means voperable after one digit is sent for-seizing said second director, means operable after a predetermined number 01 :digits have been sent to said first director for causing the remaining digits of the called 7 number to be sent to said seconddirector and for causing 'saidfirst director to transmit digits to extend the call, and means responsive to the completion of the transmitting operation of said first director for releasing the same.

. 22, In a telephone system, a first director,

a second, director, means responsive to the initiation of a call for seizing said first di- I rector, means for sending digits of a calledto J number to said first director to be registered thereon, means operable after one digit'is sent for seizing saidsecond director, and means operable {after a predetermined number of I 1 digits have been sent-to said first-director- 'for' causing the remaining digits of the called number to be sent to saidseco'nddirector and for causingsaid first director: to transmitdigits to extend the call,'and; me@ans responsive to the completion of tliejtiansmittingopera 7 tion of said; first-jdirector for releasing the I prising an incoming-and an outgoing section,

same and for conditioning said second directorto transmit digitsto complete the callc l V In a telephone system',' a;trunk line coniafirst register sender, a second registersender, means operable responsive to the initiat on of-a call, over said trunk line for asso ciating saidfirstregister sender with said trunk line meansfor sending digits of a called -numberito said first" register sender,

means operable after a 'digit has bee'irsent for associating said second register sender with saidtrunk line, means' operableafter a predetermined numberof digits have been sent to said first register 'send'er for causing the remaining digits fofjthe called number to besent to said second register sender, means in said first register sender for sending the same or other digits. overfsaid outgoing section. of; said? trunk line, and means responsive to the completion of its sending operation for I disasso'ciating'said first register sender from saidtri nkline,

124. In a telephone system, a director ,for:

registering the oifice designation ofi a called niim ber-and for transmitting the oflicecode,

- a register sender for registering the, line designating digits-of a called number and for retraiismitting them, a sequence switch in said director'having successive positions for controlling the transmittingof the digitsofthe office code,'said switch being advanced to the next succeeding position after the completionof the transmission of each digit of the code,

and means controlled by said switch in the istering the ofiicedesignations of called nllIIl bers and for transmitting: oflice codes, comprising a variable number of digits, a sequence switch having successive positions for contro1- ling. the transmitting of the digits of the ofiice codes, said switch being stepped into the next succeeding position after-the completion of the transmission of each digit of an oflice code, and means controlled by said switch in the position nextto the position in which the last digit of an 'oflice code is transmitted,

regard-less of the number of digits in the code,

for initiatin the disassociation of said director from saidline. I I

26. In a telephone system, a calling line, two'register senders, each adapted'to be con connection between said calling line and said called linen I v V v 27. In a telephone system, two register senders, a trunk line, and means for causing both. said register senders ;to send impulses over said'trunk lineto control the establishment ofa connection via said trunk line.

28. In atelephone system, a trunk line, 7 two register senders, means for successively causing said register senders to transmit im i pulses over said trunk; line to control the establishment of: a connection.

senders for registering'two different, parts of a called number, respectively, a trunk line havingga branch-at one end, and means for successively associated said register senders with said branch to cause them to control the estabhshmentof a connection via said trunk line.

means for causing said register senders to control'the extension of said trunk line .to complete the call.j

'31. In atelephone system, an oflicedirector,

trolled over said liiieseparately, a called line, and means for utilizing bothsaid registcr senders'to control the establishment of'a- 29., In a telephone system, two register: 7

30. In a telephone system, a trunk line, two

independent register senders, means respon--. sive to a call for connecting said registersen- I ders directly to said trunk linetatzadjacent points between the two ends thereof, and

a line director, autoinaticswitches controlled by the oifice director independent of theline director to trunk a calling line to the ofiicel containing the called line, and other auto-v matic switches controlled by the line director independent of the ofiice director to complete the connection. 7

32. In a telephone system, a'trunk line, a

first register sender, a second register sender, means for associating said register senders with said trunk line, means for operating the i first register sender to control the establishment of a certain class of connections, and for operating both of said register senders, each controlled over saidtrunkline separately, to 1 each controlled over said trunk line-separate' ly, to control the establishment of a different class of connections, and means for disassociating the second register sender from said trunk line during the operation of the first register sender in controlling the establish-' inent of a connection of said certain'class.

34. In a telephone system, a first and a seconddigit register, means for variablyoperating said registers to register digits,-means'-for i seizing the first register, means responsive to v a partial operation of the first register for seizing the second, and means responsive to complete operation of the first-register to a particular position for releasing the second register. v

35. In a telephone system, two digit registers, means for seizing the first register, means responsive to the registration of a digit in the first register for seizing the second register, and means responsive to the registration of another digit, providing the two digits compose a particular number, for releasing the second register.

36. In a telephone system, a first and a sec- 10nd digit register, means for seizing the first register and for providing an impulsing path thereto over which digits may be sent, means responsive to the registration of a digit on said first register for seizingsaid secondregfister, and means responsive to the registration of another digit on said first register for providing an impulsing pathto the second register. 7 V

37. In a telephone system, a first and a sec:

:ond digit register, means for seizing the first register and for providing an impulsing path thereto over which digits may be sent, means responsive to the registration of adigit on said first register for seizing said second register, means responsive to the registration of another digit on said first register for providing an impulsing path to the-second reg ster,

and means responsive to the registration of the other digit whenever the two digits registered composed a particular number for releasing said second register.

38. In an automatic, telephone system, a

register sender containing registering apparatus operable to register a 'DOItlOIl of a tele-1 phone number, sending apparatusiincsaid register sender operable under the control of the registering apparatus, a second register sender containing registering apparatus effective to register a-further portion ofthe sametelephone number, and sending appa:

ratus in the second register sender operable under the control of: the associated register-x ing apparatus.

39. In a telephone system, two register senders, registering apparatus in the first register senderoperable to register a P01111011 of a telephone number, registering apparatus in the second reg ster sender and means for operating it to register an additional pore tion of the same telephone number, sending apparatus in the first register sender and means for; operating itunder the control of the associated registering apparatus while the registering apparatus in the secondreg-- ister sender is being operated, andsending 'apparatusiin the secondregister sender and, means for operating it subsequently under the control of the. associated registering apparatus in the second register sender.

40. In an automatic telephone system, a

train of automatic switches arranged to be operated to setup a telephoneconnection from. a calling liiietoa called line, two switch controllers,- means in the first. switch con-, troller for registering a portion of the digits ids of the telephone number of a called line and, I

for operatinga portion of said train of switches in accordance therewith, andameansx,

in, the second switch controller for, registering the remaining digitsIin. the number of the called telephoneline and for operating the remaining switches in thetrainto com plete the connection to the called telephone line.

41. In an automatic telephone systemya first register sender and a second register sender, means controlled over a calling telephone line for operating registering apparatus inthe first-register sender to register a portion of the digits in a called telephone number, meansin the first registerfsender for retransmitti'ng digits in accordance with r the digits registered therein, means in the second registerl sender controlled from the calling line over a circuit path excluding the first register send'erto register additional digits. in the same called telephone number,f and means in the second register sender for retransmitting digit impulses in accordance I with the digits'registered therein.

' transmitting digitiimpulses in accordance- 42. .In an automatic telephone system, a trunk; line, a first reglster sender and a secnd. reglster sender, means for taking said trunk line for the exclusive use of a calling.

line, means controlled over said calling line and said trunk line for setting up digits in, the first register sender, means in the first I register sender for retransnnttlng d1g1t'1m-' pulses'in accordance with the digits setup therein, means subsequently controlled from said calling line and .over said trunk line while; it is still retained for the exclusive useof said calling line for setting up additional digits in the second register sender, means in the second register sender for rewith the digits. set up therein, and meansefiec 'iVe thereafter for returning saiditrunk line to common use. p V

43. In an automatic telephone system, two

registersenders, each register sender being arranged'to register'and retransmit digit im- ,pulses, and meansfor operating the second register sender to register and retransmit digit impulses after the first register sender has finished itsoperatiomand a train of anby way ofsaid trunkline, means for operat- 1 ing the secondregister senderto registered-x ditional digits, and sending apparatusin the 4 second register sender-operable under the con- I ing switch, a group o'fregister senders accestothe first of said branches,"and hunting ap I paratus arranged, to connect: any register sender-inthe second group tothe second of tomatic switches operated successively re-. sponsivetothe digit impulses sent out by both register senders.

.44. In a telephone system, a trunk line, a registersender operable over a calling line to register digits of a" telephone number, said register sender being operable in accordance with the registered digits to retransmit digit impulses to automatic'switching apparatus trol of the associated registering means to retransmit additional digit impulses over the same-trunk line to the automatic switching apparatus. 7 1 p 45. In a telephone system, a trunk line ing two branches each terminating in a huntsible to the first huntingswitch, andra group of register senders accessible to the second hunting-switch.

- 46. In a telephone system, a trunk line hav ing twobranches, two groups'ofregister send- 1 ers corresponding to sald two branches re-' spe'ctively', hunting apparatus arranged to connect any register senderinthe first group said branches.

47. In: atelephone system, atrunk line,.register senders, means for connecting two of saidregister senders to said trunk line'at the same time, a switching relay in said trunk line 4 arrangedto initiate the disconnection of said. register senders from the trunk line. and

of the connected register senders, and means means for operating said switching relay from either of said register senders. 48. Ina telephone system, a trunk line, register senders, nieans'for setting up a branch,

connection froinsaid trunk line to one of said. F register senders and for, setting. up an addi-.

tional branch connection from said trunk line for subsequently operating the line relay to sendimpulse's to the second of said registersenders. v I r 1 50. In 'a telephone systemwherein automatic switches are employed. to set up-connections betweeircalling and-called lines, a group of trunk lines over whichsaid connections are set-up, a group of register, controllers to another of said registersenders,a line re- 1 common-to said trunklines,means torta-king. I

one of said trunklines for use and for trans mitting digits thereoverto effect the setting up of connection, and means depending upon the value, of the numberrepresente'dby such digits for determining whether one'of said register --controllersisjto be connected 1 0 with the trunk-line or not.

.In witness whereof,I hereunto subscribe i my-name this 8th. day of November, AQD. 1926.

hav-

" onner e. nrcrninnson. Q 1