US1674134A - schwartz - Google Patents

Description

June 19, 1928. 1,67434f M. SCHWARTZ MULTIOFFICE AUTOMATIC TELEPHONE SYSTEM Original Filed Feb. 8, 1924 8 SheetSSheet l 1719.4 Wm? Af (m,

i n F2574 .F 1g:3 0- Tm June 19, 1928.

1,674,134 M. SCHWARTZ MULTIOFFICE AUTOMATIC TELEPHONE SYSTEM Original Filed Feb. 8, 1924 8 Sheets-Sheet 2 June 19, 1928.

M. SCHWARTZ MULTIOFFICE AUTOMATIC TELEPHONE SYSTEM a, 1924 sheet #sheet s origina lF'led Fe Michael 'E chmar'z' d W7 June 19, 1928. R,674,134

M. SCHWARTZ MULTIOFFICE- AUTOMATIC TELEPHONE SYSTEM original Filed Feb. e, 1924 s sheets-sheet 4 Junev 19, 1928.

M. SCHWARTZ MULTIOFFICE AUTOMATIC TELEPHONE SYSTEM 8 SheeTs-Sheet 5 -Imfen arf- Mchael Schwarlz' June 19, 1928. ,674,134

M. SCHWARTZ MULTIFFICE AUTOMATIC TELEPHONE SYSTEM Original Filed Feb. 8, 1924 8 Sheets-Sheet 6 MEZ-zaal Schwarz Jne 19, 31928. 1,674,134

M. SCHWARTZ MULTIOFFIQE AUTOMATIC TELEPHONE SYSTEM Original Filed Feb. 8, 1924 fda .724 f4;

H2L-gael Schwer-2z June 19, 1928. I l l,674l34 M. SCHWARTZ MULTIOFFIE AUTOMA'TIC TELEPHONE SYSTEM Original Filed Feb. 8, 1924 8 Sheets-S1166?, 8

MaI-zaal. EchME/IZz i EnH- Patented .lune 19, 1928.

uairsnsra'rss lidde .L .maar aerien.,

MICHAEL SCHWARTZ, OFCHICAGO, ILLINOIS, ASSIGNOR, BY MESIIE ASSIGNMENTS, TO

AUTOMATICELECTRIC INC., OF CHICAGO, ILLINOIS, A CORPORATION OF DELA- WARE.

MULTIOFFICE AUTOMATIC-TELEPHONE SYSTEM.

i Application led February 8, 19211, Serial No. 691,327. Renewed October 24, 1927.

The present invention relates to multioliice automatic telephone systems in general, but is concerned more particularly with lsys'cms of the above character in which call direc'- tors are employed to register, translate, and retransmit the part of the number which is indicative of the ofiice called, and the broad general object, briefly stated, may be said v to consist in the provision of new and 1mproved circuit arrangements whereby the subscriber digits (the part of a number indicative of the desired line in the particular office called) of a telephone number may be translated also and in such a manner that the capacity of a given train of automatic step by step switches may be increased so as to accommodate a larger number of subscribers without `increasing the number of switchesin the train.

There are many other objects, several of which are more or less incidental to the carryingl out of the main object, all of which will be best understood from a further perusal of the specification.

Referring now to the drawings comprising Figs. 1-12, inclusive, Figs. 1 4, inclusive, show four trunking layouts which are to be used in'explaining the objects and fea-A tures of the invention, while Figs. 5-11, in-

ratus employed in a telephone system em-V bodying the principles of the invention to enable the invention to be understood andv its utility appreciated, and Fig. 12 shows how Figs. 5-11, inclusive, should be placed together. l

Referring now to Figs. 1-4, inclusive, Fig. l is a representative layout of a 10,000-line oiiice employing the standard ten-level selectors. Only five levels, however, of the thousands selectors are used and the capacity of the oliice, which accordingly would otherwise be only 5,000 lines is brought back to 10.000 lines by the use Vof CO0-line connectors. Fig. Qshows a layout of vtwo 10,000 line otiices in which the same thousandsV and hundreds selectors are used for both oiiices; in which 200-line connectors are used, as in Fig. 1; and in which the hundreds selectors are of the twenty-group type instead of the ten-group type shown in Fig. 1.

Fig. 3 is a. layout of a 10.000-1ine office wand is somewhat similar to Fig. 1, except that twenty-group hundreds selectors. are

y sented by the hundreds selector F.

used insteadof the 20D-line connectors shown in Fig. 1.

Fig. l is a layout similar to Fig. 3, eX cept that the capacity of the connectors shown in Fig'. 3 has been increased to 200 lines and the second or lower half of the connector banks is used to accommodate a second 10,000 line oliice.

Referring now more particularly to Fig. 1, the lirst live levels of the thousands selector E are used to trunk calls to ve groups of hundreds selectors, one of which is repre- The ten levels of the hundreds selector F are used to trunk to ten groups of 20G-line connectors, of which one group is represented by the QOO-line connector H.-

Reg'arding the necessary translation in the telephone numbers, which of course are listed in the directory and called according to the decimal system, it may be pointed out that in case the thousands digit is anything from 1 to 5, inclusive, it is not translated, but if the thousands digit is anything from 6 to 0, inclusive, live is subtracted from it, or in other words, the digits 6 to 0, inclusive, are combined with the digits 1 to 5, inclusive.

. At this time it may be pointed out. that,

since only live levels of the selector E are used to trunk calls to 10,000 lines. each of the live following groups of switches handles more calls than if ten levels of the selector E were used to handle the saine number of calls. In this way, a considerable saving in the total number of switches can be made owing to the increased trunking eliiciency that is made possible whenever two relatively small groups can be combined into one larger group. v

Regarding the translation necessary in order to choose between the two wipers of the connector H, it may! be pointed out that the of banks on the connector H that are used depends upon the thousands digit. lf this digit is anything from 1-5, inclusive, the upper set of banks of the connector H' is used, while if this digit is anything from 6 0, inclusive, an artificial series of eleven impulses is sent to the connector H after the vertical movement and before the regular. numerical rotary movement, resulting in the wipers of the connector H which cooperate with the upper bank being rotated entirely over the bank, ot @elated-S, resulting the wipers of the lower bank (which are set at such an angle that they are not brought into operative relation with the associated bank contacts unless the eleven preliminary `rotary steps are taken by the switch shaft) being brought into position ready to be rotated over the )ank as soon the next and last series oi` .impulses is delivered.

In summing up the layout of Fig. l, it m ay be point-ed out that ten separate groups of numbers are combined into live composite groups,'represented by the iirst live levels of the regula-r series ot impulses which operates it to select a trunk, the circuit :wrange ments being such that ill ol'lice No. 2 is called the wiper-selecting digit is z and the upper bank is used, while itl oilice No. il is willed, the wiper-selecting digit is 3 and the lower bank oit selector F is used.

Referring now particularly to F ig. 3, it may be pointed out that the thousands digits "60, inclu-sive. when this ollice is called, are combined with the thousands digits L5, inclusive, respectively, in the manner pointed out above in connection with Fig. l. In the layout shown in Fig. 3, however, the thousands digit controls the sending` out oi" the wiper selecting digit to the hundreds selec tors, such as the selector F2, instead of conl trolling the sen-ding out ot a preliminary wiper-selecting series of eleven impulses to pick out connector wipers as in the case o Fig. l. It is thus seen that the scheme shown in Fig. l, and the scheine shown in Fig. 3 are simply two di'l'lferent methods ol obtaining the same result as regards the capacity of the switch train, and it may be pointed out that the tra'liic conditions may be such in one oii'ice as to make the use ot one layout expedient. while the traido conditions in another ol'liee ot the same system may be such that the use oit the other layout is more economical, or it may even happen that two stead of the 10G-line type. In this latter case, one bank of any one connector, such as H5 l'or example, represents lines in one office, while the other bank ot the same connector represents lines in a different oilice. f Accordingly the sending out of the preliminary series of eleven impulses between the vertical movement and the regular rotary movement of the connectors is controlled according to which ot the two offices is called.

It. may be pointed out at this time that the capacity of any one of the four trains oi switches shown in Figs. l-Lhinclusive, may be doubled. When this is done, the trailic to the hundreds selectors and connectors shown is handled in the same way as described hereinbefore and, in addition, the upper live levels of the thousands selectors, instead of being lett dead, are used to trunk calls through a new group of hundreds se-k lectors and thence by way of the connectors to the called lilies. After this is done, when a number is called which must be reached by way olf one ot the upper live levels ol a thousands selector, the thousands digit is sent out untranslated in case itis any digit Ylrom t3 to O, inclusive, but translated in case it is any digit Jfrom l to 5, inclusive, the translation being such that the thousands digit l becomes a 6; the thousands digit 2 becomes a 7 etc. Accordingly, when either of the layouts shown in Figs. Q and '4i is lused tor both halves of the Vthousands selector banks, four 10,000-line ollices located in the same building may be accommodated with one set of thousand selectors and. with only three local switches involved in any one connection. Y

Referring now to Figs. 5-11, inclusive, Figs. 5, 6, and 7 show the switching equipment employed for a connection Lfrom the line of substation A, Fig. 5, to either of the -two substations, A or A2, Fig. 7, whichsubstations are also represented in Fig. 2 as accessible to the connector'I-Ig; and Figs. 841, inclusive, show by means ot the usual circuit diagrams one of the call directors employed in making the necessary translation both in the ottico digits and the subscriber digits ot the numbers.

Fig. 5 shows the line switch C in which the line ot' substation. AY terminates and also the trunk circuit TC. which is one ot' the trunk circuits accessible to the line switch C. This trunk circuit is individual to the selector D and has associated with itfthe secondary switch SS which selects an idle di rector when the trunk circuit TC is taken -for use.

F 6 shows the thousands selector `E which is denoted in this drawing by means of the dottedrectangle bearing that reference character. The selector E is accessible to the selector D,'Fig. 5, and has access to second selectors of which the selector F is liti) lli) one. The trunliug may ie readily appre ciated by referring baclr to Fig. 2.

Fig. 7 shows the 200 lineconnector H2 whose upper wipers 251-253, inclusive, are used to complete the connection when the ele-ven preliminary rotary steps are not tal-:en by the switch shaft. rllhe lower set wipers 261-263, inclusive, are used to complete the connection in case the eleven preliminary rotary steps are taken. The fact that the lower wipers are set at an angle-with the banks is indicated .diagramn'iatically in the drawings.

Referring now particuarly to the director shown in Figs. 8411,. inclusive, the portion of the director shown in Fig. 8 comprises the impulse-control sequence switch S and the associated relays 301 and 302, together with the stop#conductor-control sequence switch S; the portion of the director shown in Fig. 9 comprises the sending switch SEN, together. with the associated relays 40S-405, inclusive, andthe release relay 402; the portion of the director shown in Fig. 10 comprises the intermediate distributing frame DF, the `oliice register OR, and the assocated relays 5214525, inclusive; and the portion of the director shown in Fig. 11 com nises'the digit registers`DR,-1-DR.4, inclusive,togeth1r with the translating relays 609 and 610.

The present system, having been thus described generally, will now be described in connection with a detailed descriptioniof the operation of the apparatus shown For this purpose it will be assumed that the subscriber at substation A,` Fig, 1, desires to converse with the subscriber at substation A', Fig. 7. As far as the present invention is concerned, the part of the number designating the desired office is immaterial and no particular number will be assigned. rFhe part of the number, however, which indicates the desired subscriber after the oflice is reached`v is 5,000, as=may be seen in Fig.

Accordingly, the subscriber at substation A; removes his receiver and dials the two oihce digits of the number, followed by the four subscribers digits 5 i O O-,0.

`S/lhen the receiver is removed at substation A, line relay of the line switch C energizes over line conductors 11 and 12 and places ground on private normal conductor 13 at armature 20, thereby making the call ing line busy immediately and closing. a

circuit through switching relay 14 and stepping magnet 16 in series.

Line relay 15 also connects step test wiper 23 to the junction of switching relay 14 and stepping magnet 16 at armature 21. In case the trunk upon which the wipers of the line switch are standine' is idle, switching relay 14 venergizes rie'ht away andseizes the said trunk. Assuming the trunk to be busy, however, there is a ground potential upon the test conductor thereof, and this ground potential is extended through test wiper to the junction of switching relay 14 and stepping magnet 16. Switching relay 14 is accordingly short circu-ited and does not energize, and stepping magnet 16 operates in a buzzer-like manner and advances the wipers 22-24, inclusive, step by step in search of an idle trunk.

Tfhen an idle trunk is reached, which trunk, it will be assumed, is the one comprising conductors 25-27, inclusive, switching relay 14, being no longer short circuited, energizes. Stepping magnet 16, however, does not energize at this time on .account of the high resistance of switching relay 14. Upon energizing, switching relay 14 opens` the test circuit and prepares the holding circuit at armature 1S, thereby making the seized trunk busy immediately; and at armatures 17 and 19 disconnects the line conductors 11 and l2 from the winding of line relay 15 and ground at armatures 17 and 19 and eX- tends' them by way of'wipers 22 and 24, conductors 25 and 27, and armatures 43 and and their resting contact-s to the windings of line relay of the trunk circuit TC. Line relay 35 thereupon energizes over the calling line and closes a circuit for release relay 216 at armature 38. Release relay 36, upon energizing, places ground on release trunk conductor 26 at armature 40, thereby completing the holding circuit for switching relay 14 of the line switch C before the slow acting line relay 15 has had time to deenergize. As a 'tui-ther result of the energization of release relay 36 of the trunk circuit TC, it closes at armature 41 a circuit through switching relay 46 and stepping magnet 47 of the secondary switch SS in series, and at armaturer42 connects test wiper 54 to the junction of switching relay 46 and stepping magnet 47. lAccordingly, the switch SS selects an idle trunk inithe same manner` as above pointed out for the line switch C. In this case it will be assumed that the director shown in the drawings is the first one found to be idle. Accordingly, when the wipers 52455, inclusive, of the secondary switch SS arrive upon the bank contacts in which the conductors 5659, inclusive, terminate, switching relay 46 energizcs; opens the test circuit and places ground on test wiper 54 at armature 50; connects up the impulse wiper 55 at armature 51; and at armatures 48 and 49 connects up wipers 52 and 53, thereby placing a bridge across conductors 62 and 64 of the selector D. This bridge includes wipers 52 and 53 of the secondary switch SS, conductors 56 and 57 and armatures 41S and 421, Fig. 9, and their resting contacts in multiple. Line relay of the selector D accordingly energizes and closes a circuit for release relay 66 at armature 7 6. Release relay 66 there- IVN) secondary llO upon energizes and places a multiple ground on release trunk conductor 63 at armature 77, and at armature 78 opens a point in the circuit of release magnet 71 and prepares a ture 415 opens the normal restoring circuit of the sequence switch S.

The above described operations have all taken place responsive to the removal of the receiver at substation A, and the apparatus is now in readiness to receive the first ollice digit in the desired number. lVhen the subscriber at substation A manipulates his calling device in accordance with the first ollice digit, a corresponding number of interruptions are produced in the circuit of line relay oit' the trunk circuit TG, and each time line relay deenergizes responsive to one of these interruptions, it closes at armature 39 a circuit for vertical magnet 504 of the oflice register OR, Fig. 10, as `follows: from ground by way of the resting Contact and armature 39, armature 51 and its working contact, wiper 55, conductor 59, series relay 301, Fig. 8, wiper 310 of the sequence switch S, the h'rst associated bank contact, conductor 321, and the vertical magnet 504, Fig. 10, to battery. By the operation of the vertical magnet 504, the wipers 511-514, inclusive, of the oflice register OR are raised step by step until they come to rest opposite the desired level et bank contacts. Relay 301, Fig. 8, is energized in series with vertical magnet 504 upon the Ii rst impulse of current delivered to the latter, and, being slow acting, maintains its armature 304 attracted throughout the entire series of impulses. Upon energizing, relay 301 closes a circuit for slow acting relay 302 which accordingly energizes and preparcs at armature 305 a circuit for stepping magnet 306 ot the sequence switch S.

At the end of the series oi impulses delivered to the vertical magnet of the office register, series relay 301 deencrgizes and opens the circuit of slow acting relay 302, and at the same time closes the circuit of stepping magnet 306 of the sequence switch S, whereupon the wipers 309 and 310 of the sequence switch S are advanced into engagement with the second set of bank contacts. An instant later, slow acting relay 302 de energizes and opens the circuit of stepping magnet 306 at armature 305.

When the calling subscriber at substation A manipulates his calling device in accordance with the second office digit, a corresponding series of impulses is delivered over the circuit above traced, to wiper 310 of the sequence switch S, Fig. 8, and thence by way of conductor 322 to rotary magnet 503 of the office register OR. Rotary magnet 503 is accordingly operated to rotate the wipers 511-514, inclusive, into engagement with the desired set of bank contacts in the selected level, which in this case is the set 564 which is allotted to ofiice #2. The jumper, associated with the bank contact on which the first code-digit wiper511 lands is connected at the other end to the third impulse-stop conductor 433, thereby predetermining that the first code digit to be sent out will be the digit 3.

The bank contact on which the second code-digit wiper 512 lands isV connected by means of a jumper to the skip conductor, thereby predetermining that the second code-digit position will be skipped, the trunking layout being such that the desired office is reached at the end of the first code digit.

The bank contact upon which the grounded wiper 513 lands is connected by means of the associated jumper to conductor 542. Aocordingly, relay 609, Fig. 11, energizes over conductor 542 and disconnects the last live associated bank contacts from the impulsestop conductors 426-440, inclusive, and connects them to the first five impulse stop conductors 531-536, inclusive. The thousands digits 6-0, inclusive, are thereby combined with the thousands digits 1-5, inclusive.

The bank contact upon which the grounded wiper 514 lands is connected by means of the associated jumper to conductor 545. Accordingly, relays 523 and 525 energize in series over conductor 545. Relay 523, upon energizing, disconnects the stop conductor 355 from the skip conductor at armature 530 and connects it to the third impulse-stop conductor 433, thereby predeterinining that a series of three impulses will be transmitted after the thousands selector has been operated and before the registered hundreds digit is sent out. Relay 525, upon energizing, disconnects conductor 356 from the skip conductor at armature 532 and connects it to the wiper 604 o1' the thousands register DR-1. Relay 525 also connects the con.- ductors 549 and 550, associated with the first and second halves, respectively, ofthe bank contacts of wiper 604, to the skip conductor and to the eleventh impulse stop conductor 541, respectively. Accordingly, it is predetermined that the setting of the thousands register DR-l will determine whether or not an extra series of eleven impulses shall be sent out between the vertical and rotary operations ofthe connector switch to be used in com leting the call.

Byt e conjoint a-ction of relays 301 and 302, Fig. 8, in response to the second office digit, the wipers ot the sequence switch S are again advanced one step. Wiper 309 at this time closes the impulse circuit, thereby starting the sender SEN, Fig. 9, to send out the iirst digit inthe omce code. However, before the description yot this operation is taken up, the description of the registration of the desired number will be completed.

When the calling subscriber at substation A manipulates his calling device in accordance with the first subscriber digit 5 in the desired number, the tive impulses ot" current which are transmitted over the previously traced circuit to wiper 310 ot' the sequence switch S, F ig. 8, are sent over conductor 331 to the stepping magnet 601 ot' the lirst digit register Dlt-1, F ig. 11. Accordingly,-the wipers 604 and 605 ot' the digit register DR-l are rotated into engagement with the corresponding set of bank contacts.

When the calling subscriber manipulates his calling device in accordance with the second subscriber digit 0, the ten impulses of current therebyfproduced, are transmitted over the above traced circuit to wiper 310 ot the sequence switch S and thence by way of conductor 332` to the stepping magnet ot the second digit register Dlt-2. Accordingly, the wiper 606 is advanced into engagement with its last bank contact.

When y the calling subscriber dials the third subscriber digit, ten impulses of cui'` rent are delivered over the impulse circuit to Wiper 310 ot the sequence switch S, and are thence transmitted by way of conductor 333 to the stepping magnet of the third digit register IDR-3, resulting in the wiper 607 being advanced into engagement with its last contact. l v

lhen thecalling subscriber dials the next and last digit 0 ot the number, ten impulses of current are delivered through wiper 310 of the sequence switch S and conductor 334 to the stepping magnet ot the toni-th digit register Dlt-4, resulting in Vthe wiper 603 being stepped into engagenientwith the last bank contact.

At the endet the registration of the last subscriber digit, the wipers 309 and 310 ot the sequence switch` S are advanced another stepand the wiper 310 engages a dead contact,'and accordingly the said wipers remain in this-position until the director is freed and tlierapparatus restored to normal.

The Voperation et the sending equipment will now be taken up. ltwill be remembered that upon the cessation ot the second series ot impulses delivered to the director, which` impulses were transmitted to rotary magnet 503 ot the otiice register OR, wipers 303 and 310 Vot theiinpulse control sequence switch S were Aadvanced into engagement with the third set ot bank contacts. vWhen this occurs, wiper 309 connects the grounded interrupter leadV over conductor 428 and through the resting contact an armature 426 to sending relay 403. As soon as interrupter 303 closesthe circuit of sending relay 403, the latter eneroifes and opens a point in i g the outgoing control circuit at armature 418. This, however, does not produce any result owing to the tact that armature 418 and its contact are shunted by armature 421 and its contact. As a further resultof the energization or sending relay 403, it closes at armature 419 a circuit for stepping magnet 406 of the sender SEN. Magnet 406 thereupon energizes and moves the associated pawl into engagement with another notch in the wiper-driving ratchet wheel, but does not move the wipers 407 and 408. Upon the subsequent deenergization ot sending relay 403, it opens the circuit of stepping magnet ot the sender at armature 419, whereupon stepping magnet 406 deenergizes and advances the wipers 407 and 408 into engagement with the iirst setof bank contacts. liper 40T engages a grounded contact thereby closing a circuit tor pick-up relay 404. iJick-up relay 404, upon energizing, prepares a locking circuit tor stop relay 405 at armature 422; closes a circuit tor stepping magnet 311 of the sending control sequence switch S at armature 420, and at armature 421 removes the shunt trom around armature418 and its contact so as to permit an interruption to be produced in the outgoing control circuit upon each ot the subsequent energizations ot the 'sending relay 403.

At the end of the third interruption produced in the outgoing control circuit, sending relay 403 deenergizes and opens the circuit of stepping magnet 406 ot the sender, whereupon the wipers 40T and 408 are advanced into engagement with the fourth set of bank contacts. l.Viper 408thercupon completes the tollowing circuit: troni ground by w ot' the 'stop-conductor-cone trol wiper 513 of the sendingecontrcl quent-e switch S', the iii-st code-digit stop conductor 341, the .lirst viper :511 ot the oiiice register OR, the bank contact upon which it is standing, the associated juiniVi-r-i', the third impulse-stop conductor 433, the fourth contact in the bank ot wiper 408 ot the sender, and stop relay '205 to battery. Stop relay 405, upon energizing, completes a locking circuit toI itsel't at armature 427, disconnect-s the dccnergized sending relay 403 at armature 426, and armature .i opens the circuit oit stepping magnet 311 ot the sending control sequence switch S, whereupon stepping magnet 311 deenergizes and advances the wipers 312 and 313 into engagement with the second set ot bank contacts. TWhen this occurs, the stop-conductor-control wiper 313 applies ground to the second` code-digt-stop conductor 343, thereby closing a circuit over the second liu Cil

code-digit wiper y512, the bank contact upon which it is standing, the associated jumper, the ship conductor, and thence to battery by way ol' the interrupter contacts and magnet 311 of the sending control sequence switch S. Stepping magnet 311 according ly energizes again and interrupts its own circuit, whereupon it deenergizes and advances the wipers 311 andy 312 into engagement Awith the third set of'bank contacts in readiness to send out the lirst subscriber digit.

As a further result of the above pointed out energization oi stop relay 405 of the sender, it cla-:esk at armature 424 a circuit through the bank contact iipon which wiper 407 is standing, and wiper 407 for stepping magnet 406 through the associated interrupter contacts. ificcordingly, the magnet 406 operates in the manner of a. buzzer until the wipers 407 and 408 are stepped to the last set ot bank contacts. 'Vhen this occurs, wiper 407 is no longer grounded and the stepping operation ceases. Furthermore, wiper 407, in passing oli the last grounded bank contact, opens the circuit of pick-up relay 404. Pick-up relay 404, however, is slow acting and does not energize immediately.

In the selector D, Fig. 5, each time the outgoing control circuit is interrupted by sending relay 403, as pointed out above, line relay 65 cle-energizes and closes a circuit for vertical magnet 72 as follows: from ground by way oi" resting Contact and armature 84, armature 7 6 and its resting contact, armature 7 8; and its working Contact, serie.J relay 6,7, and vertical magnet 72 to battery. By the successive operations of vert-ical magnet 72, the wipers 861-88, inclusive,of the selector D are raised step-by step until they stand opposite the desired level of bank contacts. Relay 67 is energized in series with vertical magnet 72 upon the first impulse of current passing through it and, being slow acting, maintains its armature attracted throughout the vertical movement. Relay 67, upon energizing, prepares at armature 79 a circuit which is completed through interrupter contacts 74 and oii normal contacts 75 ttor stepping relay 68 responsive to the closure of oil normal contacts 75 when the switch shaft moves from its normal position. Upon energizing, stepping relay 68 closes a locking circuit for it-selt' at armature 80, and at armature 8l prepares a circuit for rotary magnet 73.

Upon the cessation of the vertical movement, slow acting series relay 67 decnergizes and completes the circuit of rotary magnet 73 at armature 79. Rotary magnet- 73 thereupon energizes and advances the switch wipers 86-88, inclusive, into engagement withV the first set of bank contacts in the selected level, and near the end of its stroke,

opens the circuit of stepping relay 6,8 at in*- terrup'ter contacts 74. Relay 68 accordingly deenergizes and opens the circuit of rotary magnet 7 3 at armature 81, whereupon rotary magnet 73 deenergizes also and again closes its interrupter contacts. In case the trunk terminating in the first set off bank contacts is idle, switching relay 69 energizes imma diately. Assuming the trunk to be busy, however', switching relay 69 is shortV eircuited by the ground potential encountered on the busy test Contact by test wiper 87 and does not energize. VUnder these conditions, test relay 68 is again energized, this time through test wiper 87, and,'in addition to closing its usual locking circuit at armature 80, it again completes the circuit oi rotary magnet 73 at ari'nature 81, whereupon the' wipers are advanced another step in the above manner. i

This alternate operation of stepping relay 68 and rotary magnet 73 continues as de scribed until an idle trunk is reached, which trunk it will be assumed is the one terminating in bank contacts 89491, inclusive, and comprising conductors 92-94, inclusive'. lhen such idle trunk reached, switching relay 6,9, being no longer short circuited, energizes in series with stepping relay -68 and from the grounded release trunk conductor 63. Stepping rela-y 68, however, is not operatively energized at this time on account o't the high 'resistance of switching relay 69. Switching relay 69, upon energizing, opens the test circuit and prepares the holding circuit .at armature 83; removes ground from armature 76 ofl line relay 65 at armature 84, thereby opening the circuit of release relay 66; and at armatures 82 and 85 disconnects conductors 62 and 64 from relay 65 and extends them by way of wipers 86 and 8.8, bank contacts 89 and 91, and trunk conductors 92 and 94 to the windings of the line relay ofv the thousands selector E in the desired olice, which, in this case, is office #2. Accordingly, the vline and release re-v lays of the selector E (not shown) energize and the latter prepares the switch for oper-V ation in the usual manner.

Returning now to the director, slow acting pick-up relay 404 of the sender, Fig. 9, finally deenergizes and opensV the locking circuit of the slow actin' stop relay 405 at armature 422. Accordingly, slow acting relay 405 deenergizes after an interval and again connects up sending relay 403 at armature 406, whereupon the sender is started to send out the irst subscriber digit 5. It may be pointed out at this time that the'interval required for relays 404 and 405 to fallback one aiter the other, as described above, is utilized by the selector D in 'performing the change-over and trunk-hunting operations above described.

The sender has ben restarted, as vpointed out. above, and is now sending out the first subscriber digit 5, and when the fifth interruption in the outgoing control circuit occurs, the following deenergization of sending relay 4:03 is followed by the advance of the wipers 407 and A103 into engagement with the sixth set of bank contacts, whereupon stop relay 405 energizes over the following circuit: from ground by way'of the stop conductor control 'iper 313 of the sending control sequence switch S', Fig. 8, the third associated bank contact, the lirst subscriber digit stop conductor 351.r wiper 605 of the digit register DR*1, the sixth associated banl; contac, the right-hand armature of relay 610 and its resting contact, the fifth impulse-stop conductor 135, the corresponding contact in the sender banlnwiper 403, and stop relay l105 to battery. Responsive to the enero'ization of stop relay 405, the first subscriber digit is terminated in the usual manner and the wipers of the sequence switch S are advanced one step responsive to the opening of the circuit of stepping magnet 311 at armature L1-23.

In the called exchange, the selector E raises its wipers opposite the fifth level re s nonsive to the operation of the sender above escribed and then selects an idle trunk, which trunk, it will be assumed, is the one comprising conductors 101403,y inclusive, and extending to the' wiper selecting hundreds selector F. Accordingly, line relay 122 of the selector F is energized'over the calling loop and closes at armature 131 the usual circuitl for release relay 123. Release relay 123 thereupon energizes and places ground lon vrelease trunk conductor 102 at armature 132; opens a4 pointin the circuit of release magnet 162 at armature 133; and at armature 134shunts the lower winding of relay 101 around off normal contacts 163 for a purpose to be described hereinafter.

In the director, the wipers of the sendingcontrol sequence switch S are new in en gagement with the fourth set of associated bank contacts and ground is applied to the special wiper selecting stop conductor 355 by the stop-conductor-control wiper 313. rlhis stopping ground is extended through armature 527 and its resting contact and armature y530 and its working contact (relay 523 having been energized as hereinbefore pointed out), tothe third impulse-stop conductor 433. Accordingly, the next digit to be sent out is the digit 3 which is sent out in the usual manner and which is terminated upon the energization of stop relay 105 from the ground potential applied to the third impulse stop conductor 433 over the above traced circuit. At the end of the transmission of'this wiper selecting digit 3, the wipers of the sequence switch S are advanced another step in the usual manner and ground is' applied to the hundreds-di git stop conductor 352 by the stop-conductor-control wiper 313.

ln the selector 14", Fig. 6, line relay 102 is d-eenergized three times momentarily, rcsponsive to the sending out of the above mentioned wiper selecting digit and, accordingly, three impulses of current are transmitted at armature 31 to vertical magnet 16e by way of armature 133 and its working Contact and series relay 12"1. 'By the operation of vertical magnet 164, the shaft of the switch is raised three steps and carries the wipers opposite the third level of banli contacts. The switch shaft also engages the shaft springs and closes the contacts 10e'. and 105 which are both placed so as to be operated when the shaft is raised three steps, as is indicated on the drawing. Upon theclosure of the shaft-spring contacts 105, relay 127 is energized from the grounded release trunk conductor 102 and through the normally closed contacts controlled by armature 129 of relay 121. Upon energizing, relay 127 locks itself to the grounded release trunk conductor 102 at armature 1415, and at armatures 1113, 14A, and 1416 disconnects the upper set of wipers and connects up the lower set of wipers. Slow acting series relay 121 is energized throughout the vertical movement and closes a point in the circuit ofstepping relay 125. Stepping relay 125, however, does not energize on account of the fact that its circuiti is open at armature 130 of relay 121. Series relay 12st also maintains the ground potential disconnected from the shaft contacts 104 at armature 135.

At the end of the vertical movement, series relay 124 deenergizesv and closes at armature 135 a circuit for release magnet 162 which includesthe shaft spring contacts 1011, resting contact and ar1miture`123, and off normal contacts 163. 1t will be noted that the lower winding of relay 121 is included in this circuit except for the fact that it is shunted by olf normal contacts 163. itesponsive to the closure of this circuit, release magnet 162 energizcs and closes at armature 161 a locking circuit for itself independent of armature 135 and the shaft spring contacts 1011#l Release magnet- 102 also permits the shaft of the wipers of the switch to be' restored to normal position, and when the shaft reaches its normal position, it removes the shunt from around the lower winding of relay 121 by opening the off normal contacts 163. -When this occurs, relay 121 energizes; closes a locking circuit for itself and opens a point in the initial circuit of relay 127 at armature 129; closes a point in the circuit of stepping relay 125 at armature 130; and at armature 123 opens the circuit of 'its lower winding and release magnet 163, whereupon release magnet 163 becomes deenergized.

The net result oit' the transmission of the preliminary digit 3, it will be noted, is that the selectorI F has been raised to the third level, whereupon the wiper switching relay 127 became energized and disconnected the upper cet oi' wipers and connected up the lower set oit wipers, and the shaft and wipers have been reshircd to normal preparatory to the reception of the hundreds digit.

In the director, the hundreds digit 0 is now transmitted and is terminated responsive to the energization of stop relay 405 over the 'following circuit: from ground by way oi the step conductor control wiper 313 oit the sequence switch S, F 8, the fifth associated bank Contact, the hundreds digit stop conductor 352, wiper 606 oi' the second digit register Dlt-2, the eleventh associated bank contact, the tenth impulse stop conductor 440, the associated contact in the sender bank, wiper 408, and stop relay 405 to battery. Responsive to the energization oi stop relay 405, the circuit of stepping magnet 311 of the sequence switch S is opened at armature 423 and the wipers 312 and 313 are advanced into engagen'ient with the sixth set of bank cont cts.

In the selector F, Fig. 6, line relay 122 is deenergized ten times momentarily in resaonse to the above described operation ot the sender and, upon each deenergization, closes the previously traced circuit of vertical magnet 164. By the ope 'ation of vertical magnet 164, the switch wipers are raised opposite the tenth level of bank contacts. Series relay 124 isy again maintained energized throughout the vertical movemen and in conjunction with olf normal contacts 167, which close upon the first vertical step, completes at armature 136 a circuit through armature 130 and its working contact and interrupter contacts 166 ior stepping relay 125. Stepping relay 125, upon energizing, closes a locking circuit 'for itself at armature 137, and at armature 13S` prepares a circuit for rotary magnet 165. F rom this point, the operation of the selector F' is identical with the operation of the selector D previously described.

kBriefly, the rotary movement is initiated upon the decneroization of slow acting series relay 124 at the end of the vertical movement and continues until an idle trunk is reached by the wipers 150-152, inclusive, which trunk it will be assumed is the one comprising conductors 153455, inclusive, and ending to the connector HL. When this occurs, switching relay 126, being no longer short circuited, energizcs in series with stepping relay 125 and switches the connection through to the selected set of wipers at armatures 139, 140 and 142, and at armature 141 opens the circuit oi release relay 123 which subsequently deenergizes and removes thelower winding of relay 121 from around oli' normal contacts 163 so as to prevent the said lower winding lrom intertering with the regular releasing operation ot' the selector which is to take place subsequently.

In the connector H2, line relay 201 now energizes over the calling loop responsive to the above mentioned seizure oi" the associated trunk and closes at armature 209 a circuit tor release relay 203. thereupon ei'iergizes; opens a point in the circuit oif release magnet 231 and lrepares a circuit for vertical magnet 230 at armature 21.2; prepares a circuit lor the upper winding oit switching relay 203 and for busy relay 206 at armature 2li; and at arn'iature 210 places ground on release trunk conductor 154. Y

In the director, when the sender is restarted, it continues to operate until ten impulses oi? current have been sent ont, at which time stop relay 405 is energized over the following circuit; from ground by way et stop-condactor-control wiper 313 oif the sequence switch S', the sixth associated bank Contact, the tens digit stop conductor 353, wiper 60T of the third subscriber digit register Dlt-3 the eleventh associated bank contact, the tenth impulse stop conductor 440, thi associated contact of the sender bank, wiper 408, and relay 405 to battery. The energization of stop relay 405 terminates the tens digit in the usual manner and also results in the advance of the sequence switch C into engagement with the next set ot bank contacts, whereupon stop-conductor-control wiper 313 applies ground to the special stop conductor 356, which stop conductor connected through armature 352 and its working contact (relay 525 having been energized in series with relay 523 as above pointed ont), and conductor 548 to wiper l604 ot the `lirst or thousands digitregister Dil-1.

Since wiper 604 has been advanced into engagement with the sixth associated bank contact in response to the calling of the thousand: digit 5, as above pointed out, the ground potential is extended by wiper 604 to conductor 549 and thence through armature 533 and its working contact to the skip conductor resulting in the usual operation of the sequence switch S to automatically advance its wipers to the neXt set of bankcontacts. Accordingly, the extra set of eleven preliminary impulses cannot be delivered to the connector' H2 between the, tens and units digits, and the upper set of wipers willl therefore be used to complete the connection which is to be extended to the line of substation A whichterminates in the upper bank ci? connector H2. 1

In the connector H2, line relay 201 deenergizes ten times mon'ientarily responsive to the above operation of the sender and, upon each deenergization, completes a circuit for eiease relay 203 .'1-

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vertical magnet 230, the circuit at the time of its lirst closure being as follows: from ground by way of armature 209 and its resting Contact, armature 212 and its working contact, the contact of olf normal spring 229 and said spring, series relay 204, and vertical magnet 230 to battery. By the operation of vertical magnet 230, the shaft and wipers of the connector H2 are raised step by step until the latter stand opposite the tenth level of bank contacts. Relay 204 is energized in series with vertical magnet 230 and, being slow acting, maintains its armature 213 attracted throughout the vertical operation and maintains its own circuit and that kof vertical magnet 230 intact after the off to operate after the usual `interval between digits and transmits the last digit in the number.' This digit is terminated upon the energization of stop relay 405 of the sender through the stop-conductor-control wiper 513, the eighth associated bank contact, the units-digit stop conductor 354, wiper 608, the bank contactupon which it is standing, the associated impulse-stop conductor, and

wiper 408 of the sender. Upon the energization of stop relay 405, the last digit in the number is terminated and the wipers of the sequence switch S are .again advanced one step in the usual manner. At this time, the wiper 313 grounds the last contact in its bank and accordingly Igrounds conductor 59,

ythereby closing a circuit which extends from ground by way of the said conductor 59, the

' associated contact inthe bank of wiper 55 of the secondary switch SS, Fig. 5, wiper 55, working contact and armature 51, armature 39 and its working contact, and switching relay 37 to battery. Switching relay 37 of the trunk circuit TC thereupon energizes and locks itself to the grounded release' trunk conductor 63 at armature 44, an'd at armatures 43 and 45, disconnects conductors 25 and 27 from the windings of line relay 35 and extends them to trunk conductors 62 and 64, respectively, thereby bridging lthe calling line across said conductors 62 and 64 and at the same time disconnecting the control circuit of the sender from across the said conductors. Line relay deenergizes responsive to being disconnected at armatures 43 and 45 and opens the circuit of release relay 36 at armature 38. Release relay 36 accordingly decnergizes after an interval and removes ground fromrelease trunk conductor 63 at armature. 40, leaving the established connection to be held up by the ground 'potentiele applied te release' trunk condii'ctr 154 by release relay 203 of the connector H2, Fig. 7. Release relay 36 of the trunk circuit TCA also opens the circuit of switching relay 46 of the secondary switch SS at armature 41, whereupon switching relay 46 deenergizes A and disconnects its wipers, thereby freeing the director.

In the director, release relay 402 deenergizes responsive to the removal of ground from the release trunk conductor 58 when the director is freed as pointed out above and closes at armature 416 the normal restoring circuit of the sender SEN which is effective only in case the director is freed while the sender is not in its normal position. As a further result of the deenergization of release relay 402, it closes at armature 415 the normal restoring circuit of the sending control sequence switch' S, whereupon the wipers 312 and 313 are advanced the remaining step to their normal position, magnet 313 being energized through wiper 312. As a still further result of the deenergization of release relay 402, it applies ground to release conductor 401 at armature 417, thereby closing a circuit for the release magnet of the sequenceswitch S, for the release magnet of the office register OR, and for the release magnets of digit registers DR-1-DR-4, inclusive. Then this occurs, release magnet 307 of the sequence switch S energizes through the associated off normal contacts 308, and the wipers 309 and 310 are restored to normal position in the usual manner, whereupon the circuit of' release magnet 307 is opened at olf normal contacts 308. Release magnet 502 of the o'Hice register OR is energiied through the associated 0H normal contacts 501` whereupon the wipers 511-514, linclusive, are restored to normal position in the usual manner. The digit registers DR-1DR-4, inclusive, are restored to normal position in the same manner as the sequence switch S.

Responsive to the restoration of the wipers of the ofi-ice register OR- to normal, relays 523 and 525, Fig. 10, and relay 609, Fig. 11, deenergize.

The various pieces of apparatus of the director have been restored to their normal positions and the director is now in readiness to handle' another call.

In the connector H2, Fig. 7, line relay 201 is momentarily deenergized for each of the interruptions produced inits circuit by the hereinbefore described operation of the sender in sending out the last digit of the number, and upon each deenergization, line relay 201 closes a circuit for rotary magnet 232 as follows: from ground by way of armature 209 and its resting contact, armature 212 and its working contact, normally opened contacts controlled by off ,normal tact, resting contact and armature 219, armature 220 and its resting Contact, and rotary magnet 232 to battery. By the operation of rotary magnet 282, the wipers 251-255, inclusive, and the wipers 261-263, inclusive, are rotated step by step until the former come into engagementwith the bank contacts 2511-250, inclusive, ot' the line of substation A. The wipers 261-263, inclusive, it may be pointed out, do not engage any of the associated bank contacts owing to the fact that the extra series ot' eleven impulses were not transmitted between the tens and units digits.

Relay 207 of the connector is energized 1n multiple with rotary magnet 232 and, being slow acting, maintains its armature attracted throughout the rotary movement. Upon energizing, relay 207 disconnects testwiper 252 trom the upper winding ot' switching relay 208 and connects it to busy relay 206, and at armature 222 places a shunt around armature 219 and its resting contact as a precaution against the circuit of the rotary magnet being opened at armature 21,9v in case busy relay 20G energizes during the rotary movement due to wiper 252 passing over grounded test contacts.

Assuming the called line to be busy, busy relay 206 is energized through test wiper 252` and from a ground potential encounteredvon the busy test contact 255 and prepares a locking circuit for itseli:l at armature 218; opens a point. in the circuit of the rotary magnet at armature 219; and at armature 220 connects the busy lead to the lowerv heavy talking conductor, thereby sending a busy signalling current back over the established connection to the called sub station. Vhen relay 207 deenergizes, itdis-- connects rotary magnet 232 'from the impulse circuit at armature 222 (armature 219 having been operated), and at armature-221 completes the .locking circuit for busy relay 206 and disconnects test wiper 262 from the said busy relay.

The calling subscriber, upon hearing the busy tone, replaces his receiver, whereupon the established connection released in a` manner to be explained hereinafter.

In the present case, however, it will. be assumed that the line of substation A is idle when called as herei'nbetore described. in which case busy relay 206 is not energized when the wipers 251-253, inclusive, come to rest upon the terminals ot the called line and, when slow acting relay 207` deenergizes at the end or" the rotary movement, it disconnects test wiper 252 from the winding of busy relay 206 and connects it to the upper winding of switching relay 208 at armature 221, thereby closing a circuit for switching relay 208 as follows: from ground by way of the working` contact and armature 211, ar-

mature 218 and its resting contact, upper` winding ot switching relay 208, resting contact and armature 221, test wiper 252, test contact 255, and thence to battery by way o1' the switching relay and stepping magnet of the associated line switch (not shown), which line switch-may be the same as the line switch C, associated with the line ot substation A. Responsive to the closure ot this circuit, the switching relay ot' the called line switch energizes part way in the usual manner and disconnects the bridge across the line conductors thereat. Y

In the connector H2, switching relay 208 energizes over the above traced circuit and at its lightly adjusted armature 221 closes a locking circuit for its lower winding; disconnects rotary magnet and slow acting relay 207 at armature 220; places direct ground on the test wiper at armature 224; and at armature 223 and 227 connects up the line wipers, whereupon ringing current is projected out over the called line to ring` the bridged bell at the called. substation. This ringingfcurrent returns by way ot the upper line wiper 251 tobattery by way ol' the upper winding of ring cut-oil3 relay 205.

Then the called subscriber responds to the ringing of his bell by removing his receiver, a direct current bridge is closed across the associated line conductors, whereupon ring cutoll` relay 2.05 energizes; closes a locking circuit for itself at its lightly adjusted armature 216 and at armatures 214 and 217 disconnects the line wipers from its own upper winding` and the generator lead and connects them instead to the windings of the back bridge battery feed impedance 202. rllhe desired connection is now completed` and the subscribers may converse as desired.

Then the conversation is completed, the two subscribers replace their receivers. lVhen the receiver is replaced at the called substation A', talking battery merely ceases to flow in the called line, but when the re` ceiver is replaced at substation A, the circuit ofy line relay 201 of the connector H2 is opened, whereupon line relay 201- deenergizes and opens the circuit ot release relay 203. Release relay 203, upon energizing aitter an interval, removes ground from release trunk conductor 154 at armature 210,- and at armature 212 completes a circuit for release magnet 231. through off `normal contacts 228, whereupon the switch is restored to normal position in the usual manner,

Responsive to the removal of the ground potential from conductor 154, ring-cut-otl" relay 205 and switching relay 208 of the conf neetor H, relays 121, 126, and 127 of the selectorF, the switching relay not shown) Vof the selector E, switching relay 69 of the selector D, switching relay 37 of the trunk circuit. TC, and switching relay 14 of the line switch C all deenergize. Responsive to further that, when the deenergization of the relays mentioned, the associate-d switches are released in the usual manner. The entire connection is now released and the apparatus involved therein may now be used in setting' up a subsequent connection.

In order to explain how the necessary translation is eiected when the thousands digit is above 5, and in order to explain how the klower set ot wipers of the connector H2, Fig. 7, are used when such translation of the office digit takes place, it will now be assumed that the subscriber at substation A desires to converse with the subscriber at substation A2, Fig. 7. lt will be assumed the receiver is removed at substation A, the line switch C selects the t-runk circuit TG, and that the secondary switch SS selects the director shown in the drawings. Accordingly, responsive to the manipulation of the calling device in accordance with the cnice digits belonging to oiice #2', the wipers ot the oliice register OR, Fig. 10, are raised opposite the desired level in the hereinbefore described manner, and are then brought into engagement with the set of bank contacts 564 ot the oiiice #2 as before explained. v

Responsive to the manipulation of the calling device at substation A in accordance with the four subscriber digits 0000, the digit registers DR-1-DR-4, inclusive, are set upon the corresponding bank contacts in the usual manner.

. The ofice code is at this time sent out in the same manner as hereinbetore described, (operating the selector D to seize the selector E), after which the stop conductor control wiper 313 of the sending control sequence switch S is ladvanced into engagement .with its third bank contact, thereby placing ground through the thousands digit stop conductor 255 of the wiper 605,l which as explained hereinbefore has been advanced ten steps and is now in engagement with the last of its bank contacts. Since relay 609, Fig. 11, is energized through the lower wiper of' the office register and through conductor 542, the last contact in the bank of wiper 605, is now disconnected from the tenth impulse stop conductor 440 and is connected.

instead to the ifth impulse stop conductor 435. Accordingly, the thousands digit to be sent out is the thousands digit 5, which causes the selector E', Fig. `6, to be raised to the iifth level toselect a hundreds selector in the corresponding group, the selector F', for example, in the same manner as described hereinbefore.

Since relay 523, Fig. 10, is energized as in the preceding example when the substation A was called, the wiper-selecting digit 3 is delivered to the selector F', causing it to select the lower set ot wipers in the same manner as before. Following this, the hunlll quence switchS are advanced into engagey ment with the seventh bank contact, in which the special stop conductor 356 terminates. Ground is accordingly extended over stopconductor 356 and through armature 532 and its working contact (relay 525 being energized in series with relay 523), to wiper 604 of the thousands-digit register Dlt-1, by way of conductor 548. Since wiper 604 is standing on the last halt of itsv bank instead of the iirst half, the ground potential is not extended to the skip conductor as it was in the case just described when the called subscriber was the one at substation A', but is extended instead through co-nductor 550 and armature 534V and itsl working contact, to the eleventh impulse-stop conductor 441. Accordingly, eleven interruptions are produced in the cir cuit ot line relay 201 of the connector H by the sender which results in the wipers 251-253, inclusive, being rotated entirely over the associated bank 'of contacts, and in the wipers 261-263, inclusive, being brought within one step of the associated bank ot contacts in readiness to be brought into engagement with the desired set ot contacts responsive to the transmission of the units digit. In the director. wiper 313 of the sending cont-rol sequence switch S is advanced into engagement with the eighth associatedv bank contact in the usual manner, following the transmission of the above mentioned series of eleven impulses, and the last digit O is s et out in the hereinbe- Jfore described manner, whereupon the sequence switch S is again advanced and the director is released and the connection switched through as described hereinbefore.

In the connector H2, Fig. 7, the wipers 261-263, inclusive, are advanced intovengagement with the bank contacts 2644266, inclusive, responsive to the sending out ot' the lastdigit 0. From this point on the operation is as described hereinbefore.

Reterring now particularly to Fig. 10, it will be noted that when this director is used in completing a call to a line in otiice #2, Fig. 2, the wiper 513 completes a circuit over one ot the contacts 563, the associated jumper, and conductor 542 for the trans lating relay 609, as is the case when the ofiice #2 is called. Wiper 514, however, instead of completing a circuit over conductor 543 for the relays 523 and 525 in series, as is the case when o'flice #2 iscalled, completes a circuit over conductor 544 for the relays 524 and 525 in series. Accordingly, the wiper selecting digit to be delivered to a hundreds selector, such as the hundreds selector F, Figs. 2 and 6, is two instead of three, armature 531 of relay 524 connecting conductor 355 to the second impulse-stop conductor 532 instead of to Vthe third im pulse-stop conductor 433, as is the case when relay 523 is energized. Otherwise the number received by the director and intended for oflice #2 is handled just the same as described hereinbefore for a number received by the director a-ndintended for oiiice 2. #When a call is received by the director which is intended for oiiice #1, Fig. 1` the i director must not send out a wiper selecting digit just prior to the sending out of the hundreds digit, on account of the fact thatv the hundreds selector F, Fig. 1, has only one set of wipers. Accordingly, the fourth bank contact in the set allotted to ofiice #1, Fig. 10, instead of being connected to either of the conductors 544 and 545, is connected to conductor 543, and relay 525 is energized alone and performs the hereinbefore mentioned function of shifting the circuits so that the sending out of the eXtra series of eleven preliminary impulses by the tens and units digits is dependent upon the thousands digit dialled.

When a call is received by the director shown, that is intended for a. line in oflice #3, Fig. 3, the wipers 511-514, inclusive, are brought into engagement with the bank contacts 565, Fig. 10, as is indicated in the drawings. In this case, the bank contact on which the third wiper 513 of the office register OR stands, is connected by means of a Yjumper to the conductor 542, as explained in connection with the preceding example, so as to pull up the tianslatingY relay 609 in order to send out all of the calls through the first five levels of the selector E', Fig. 3. In addition to the above, the bank contact engaged by the fourth wiper 514 of the otlice register OR is connected by means of a jumper to conductor 546, so as to energize relay 522. Relay 522, upon energizing, disconnects conductor 355 from the skip conductor at armature 527 and extends itl by way of conductor 548 to wiper 604 of the thousands-digit register DR-l. Relay 522 also connects the two conductors 549 and 550 coming from the contacts in the bank of wiper 604 to the second and third impulsestop conductors 432 and 433, respectively. Accordingly, after the thousands digit is transmitted. and before the hundreds digit is transmitted, either the digit 2 or the digit 3` will be transmitted in order to; effect the correct wiper selection at the twenty group hundreds selector F2. This wiper selection is controlled in accordance with the thoustands digit registered by the thousandsdigit register Dlt-1, and if the thousands digit is from 1 to 5, inclusive, the wiperselecting digit 2 is sent out to selectthe upper set of wipers: of the selector F2, and if the thousands-digit register is from 6 to 0, inclusive, the wiper-selecting digit 3 is sent out, resulting in the lower set of wipers of the selector F 2, Fig. 3, being selected.

It will' be noted that in this case. it is not necessary to make any arrangements for controlling the selection of the wipers of the connectors, such as connectors H3 and Hgowing to the fact that these connectors are of theI 100 line. type, having only a single set of wipers.

When the director shown is'used in completing a call to oice #4, Fig. 4.f the wipers of the otlice register ORv are broughtV into engagement with the bank contacts 566 whose third and fourth contacts are jumpered in exactly the same way as the corresponding contacts associated with oflice #3. Accordingly, when the callV is trunked to the selector E3 in accordance with the junipering of the contacts engaged by the wipers 511 and 512, the number is transmitted in the same manner as explained in connection with office #3 and the upper set of wipers of the connector in use is employed to eomplete the connection, the upper set of wipers of the connectors H5' and H6 corresponding to the single set of wipers of the connectors H3 and H4.

When, however, thel present director .is used to complete a connection to otlice #4', the wipers of the office register are brought into engagement with the bank contacts '567, whereupon relays 521 and 522 are energized in series over conductor 547. Relay 522 performs the function above described in connection with the trunking of calls to o'liices #3 and #4 and relay 521 performs the added function of disconnecting conductor 356 from the skip conductor and connecting it to the eleventh impulse-stop conductor 441, thereby preedetermining that the wiper-selecting digit 11 is to be sent out after the transmission of the tens digit and before the transmission of the units digit, so as to cause the lower set of wipe-rs of the connector in use to be usedy in completing the connec tion instead of the upper set, as is` the case when relay 522 is energized alone.

As point-ed out hereinbefore, either of the layouts shown in Figs. 2V and 4, when du.- plicated by the addition of the necessary switches accessible to the sixth to tenth levels, inclusive, of the. thousands selectors, provides for four 10,000-1ine oices reached.

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