US2337642A - Automatic toll ticketing system - Google Patents

Description

Dec. 28, 1943. A. .J. BUSH AUTOMATIC TOLL TICKETING SYSTEM Filed June 27, 1942 4 Sheets-Sheet 1 lNVENTO/P A. J BUSCH 96. M

ATTOR/VB Dec. 28, 1943. A. J. BUSH 2,337,642

AUTOMATIC TOLL TICKETING SYSTEM Filed June 27, 1942 4 Sheets-Sheet 2 v lNl/ENTOR A. J BUSCH A 7' TORNE V Dec. 28, 1943. A, J. BUSH AUTOMATIC TOLL TICKETING SYSTEM 4 Sheets-Sheet s Filed June 27, 1942 ksu b 555.5% MQQU m 02 .53 E

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A. J. BUSCH Dec. 28, 1943. BUSH 2,337,642

AUTOMATIC TOLL TICKETING SYSTEM Filed June 27, 1942 4 Sheets-Shet 4 Fla 4 T0 INTERMEDIATE IDENTIFIER T0 usr IDENTIFIER 70 LAST IDENTIFIER FIR-ST IDENTIFIER can: LEADS lNl/ENTOR A. J BUSCH V6P6. M

A7 TORNEV Patented Dec. 28, 1943 AUTOMATIC TOLL TICKETING SYSTEM Aloysius J. Busch. Madison, N. J., assignor to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Application June 2'7, 1942, Serial No. 448,759

6 Claims.

This invention relates to a telephone system and more particularly to a toll ticketing system of the type disclosed in the application of J. W. Gooderham, Serial No. 448,782, filed concurrently herewith.

In the system disclosed therein provisions are made whereby subscribers may secure connections to the nearby toll area by dialing. This is accomplished by the provision of a group of automatic ticketing trunks, each provided with a ticket printer, to an idle one of which a call- .ing subscriber may secure a connection by dialing one, two or three digits or letters of the ofiice designation of a subscriber's line which terminates in an ofiice in the nearby toll area and from which trunk a connection is extended by selector switch equipment. The selector switch equipment by which the connection is extended from a ticketing trunk is controlled by senders, an idle one of which is associated with a trunk by a trunk finder individual to the sender when the trunk is taken for use. The sender is also equipped to control a ticket printer to print the office code and numerical digits of the calling line number, the oiiice code and numerical digits of the called line number, and to print other information required on the toll ticket. It is therefore essential to reconstruct the ofiice code digits which a subscriber dials to extend a connection to a ticketing trunk and to identify the calling line. For this purpose a plurali y of identifiers is provided, an idle one of which is associated with a sender over an identifier-connector following the seizure of the sender and which identifier is then connected directly with the callmay be terminated in a bank level of a first selector or a bank level of a second selector or a bank level of a third selector or may have branches terminating in bank levels of first, second. and third selectors.

In some cases where the trafiic to a particular oiiice in the toll area is not great, a full selector bank level having access to ten trunks may not be necessary. It is then possible through the use of a divided level selector of the type disclosed in. Patent 2,249,067, granted July 15, 1941, to P. W. Wadsworth, to provide access to two groups of trunks over which connections may be secured to difierent terminating offices. In order, however, that on such calls a wider choice of automatic ticketing trunks may be secured, the trunks of each group outgoing from the divided bank level terminates in rotary out-trunk secondary switches, one group of such switches having access to a maximum of twenty of the automatic ticketing trunks and the other group of such switches having access to a maximum of twenty other ticketing trunks.

Each ticketing trunk is provided with a sleeve relay connected to the sleeve conductor of each bank level appearance of the trunk in first, second or third selector banks or in the bank of a divided level selector and these relays control the establishment of signaling circuits over code leads whichi are extended to the identifier over contacts of the operated trunk-identifienconnector, there being one such code lead for each ofiice route which may be completed over the trunk. These code leads are employed to assist the identifier in reconstructing the office code digitsof a wanted line number dialed by a subscriber to seize a ticketing trunk. A disclosed in the application of L. J. Scott, Serial No. 448,785, filed concurrently herewith, the twenty trunks access hle to an out-trunk secondary switch are divided into two or more minor subgroups each of which is associable with an identifier over a different trunk-identifier-connector by providing access to each subgroup of trunks over different portions of the bank of the out-trunk switch and by providing an additional bank on the outtrunk switch over the separate portions of which code leads each relating to the same oilice route may be extended to the identifier through different trunk-identifier-connectors. By this distr bution of trunks, the danger of rendering an entire group of twenty trunks unavailable for completing a connection to a particular ofiice is avoided.

It is the object of the present invention to increase the efi'iciency of a system of the abovedescribed character by enabling the trunk to be reassigned from one trunk group to another with a minimum of maintenance effort and to be asigned to more than one trunk group to secure the trunk efficiency available through the use of the graded multiple; by increasing the trunk access of the out-trunk secondary switches and simplifying the cross-connection field involving the code leads outgoing therefrom and by the simplification of the trunk-identifier-connector circuits.

In accordance with the present invention this object is obtained by providing three code-connector circuits for each office building in addition to the maximum of ten trunk-identifier-ccnnector circuits. A single cross-connection rack is associated with the three code-connector circuits upon which all of the code leads from all of the trunks terminate. The code leads from one third of the trunks of each subgroup are associated with the No. 1 code-connector, th code leads from the second third of the trunks of each sub.- group are associated with the No. 2 code-con.- nector and the code leads from a third third of the trunks of each subgroup are associated with the No. 3 code-connector. This distribution of the code leads reduces the hazard of tying up ticketing service so that should a trouble condition arise on any code-connector not more than one third of the trunks of any subgroup will be afiected. By the provision of the code-connectors for extending the code leads from the trunk to an identifier, the trunk-identifier-connectors are simplified in that no provision is necessary for extending code leads therethrough. To increase the trunking eificiency of the out-trunk secondary switches, the banks are arranged to have access to twenty-one trunks divided into three subgroups of seven trunks each and with the code leads thereof associated respectively with the three code-connectors rather than to have access to two subgroups of ten trunks as heretofore proposed.

As illustrated herein, a subscriber desiring a connection to a line terminating in an office of a nearby toll area first removes his receiver from the switchhook whereby an idle line finder, paired with a first selector, is started in search of the calling line and as soon as the line is found, the usual dial tone is transmitted. Upon hearing the dial tone, the subscriber then proceeds to dial the ofiice code and numerical digits of the wanted line number. In response to the dialing of one or more of the ofiice code digits, the selectors of a switching train, including the first selector, are operated to extend a connection from the calling line to an idle tandem or automatic ticketing trunk accessible from all lines of the ofiice in which the calling lin terminates, over which trunk a connection may be further extended to the ofiice in which the wanted line terminates.

Immediately following the seizure of the trunk, an idle sender common to a plurality of such trunks is associated with the seized trunk over a trunk finder. The sender i provided with registers for registering the remaining digits of the called line number dialed by a Calling subscriber. Since, however, a digit dialed by a calling sub.- scrlber might be lost during the time elapsing between the seizure of the trunk and the seizure of an idle sender, the trunk is provided with a digit register for registering the digit dialed following the last code digit dialed to reach the trunk. On calls to certain offices the trunk may be seized by a first selector in response to the dialing of a first code digit. On calls to other oflices the trunk may be seized by a second selector in response to the dialing of two ofiice code digits. On calls to still other offices the trunk may be seized by a third selector in response to the dialing of three office code digits. In other cases a trunk may be seized in response to the setting of a selector switch, primary trunks from a, bank level of which terminate in rotary out-trunk secondary switches which in turn have access to ticketing trunks and which normally stand on the terminals of an idle preselected trunk. Since a trunk may be seized in response to the dialing of one, two or three code digits, the trunk register may register either the second or third code digit or the thousands numerical digit and the first dial impulse responsive register of the sender may register either the third code digit, the thousands numerical digit or the hundreds numerical digit.

As soon as the first digit has been registered in the sender, an idle identifier for identifying the calling line and for reconstructing the called ofiice code digits dialed by the calling subscriber is associated with the sender over an identifierconnector and the identifier is associated directly with the calling trunk over that one of a plurality of trunk-identifier-connector circuits which has access to the calling trunk. Each of the trunk-identifier-connector circuits has access to a subgroup of twenty trunks and each trunk has a cross-connection field associated therewith over which cross-connections may be made from each trunk of the subgroup to a control conductor extending through the associated trunk-identifier-connector to give the identifier seized for serving the connection, information concerning which one of the three code-connectors is to be employed to extend code leads from the calling trunk to the identifier. ie identifier then proceeds to operate the proper one of such codeconnector circuits. Thereupon office code identifying equipment associated with the trunk and selectively operated in accordance with whether the trunk was seized over a first, second or third selector bank level, establishes a record in the identifier from which the ofiice code digits dialed to reach the trunk may be reconstructed and if other code digits have ben registered by the trunk register or by the first register of the sender, such registration or registrations are also transferred to the identifier whereby from all such data registered in the identifier, a route relay is operated which is instrumental in furnishing all of the information required by the sender and the ticketing equipment of the trunk concerning the called oifice and the manner in which the call should be ticketed.

The invention having been described in a general manner, reference may now be had to the following detailed description thereof taken in connection with the accompanying drawings in which:

Fig. 1 shows schematically calling lines, line finders and trains of first, second and third selectors for extending connections from a calling line to automatic ticketing trunks, three of which are illustrated, and a selector switch of the type having access over a divided bank level to two groups of outgoing trunks;

Fig. 2 shows a rotary out-trunk secondary switch accessible from a trunk incoming from a divided bank level switch and having access to three minor groups of automatic ticketing trunks and some of the apparatus of three ticketing trunks located respectively in the three minor groups of trunks;

Fig. 3 shows the three code-connector circuits for extending code leads from the trunks to that one of a plurality of identifiers which has been seized by a sender in response to the seizure of a ticketing trunk; and

Fig. 4 shows one of the trunk-identifier-connector circuits over which control conductors from groups of automatic ticketing trunks may be extended to that one of a plurality of identifiers which has been seized by a sender in response to the seizure of a ticketing trunk and a portion of the apparatus of an identifier by which the code-connector circuits of Fig. 3 are controlled.

For a full disclosure of the present invention, Fig. 2 should be placed to the right of Fig. 1;

Fig. 3 should be placed to the right of Fig. 2 and Fig. 4 should be placed to the right of Fig. 3.

The line finders I03, Hi l and H25, the first selectors I06, ill! and tilt and the third selector ill may be of the well-known step-by-step type and the selectors maybe controlled directly by a subscribers dial to establish local connections or to establish a connection to an idle ticketing trunk such as trunk H3, H4, or H5 should the subscriber desire a connection to a subscribers line which terminates in the toll area adjacent to the exchange area in which the calling line terminates. The ticketing trunks H3 and H5 are disclosed, as having bank level appearances in first, second and third selectors and these same trunks may have appearances in more than one level of the same switch, whereby the trunks may be seized in response to the dialing of the first code digit of certain distant oifice designations,

in response to the dialing of the first and second code digits of other office designations and in response to the dialing of the three code digits of still other ofiice designations. The trunk lid might be similarly terminated in the bank levels of first, second and third selectors. In the commercial us of the system, however, a plurality of subgroups of trunks would be required to handle the toll traffic, for example, 200 trunks divided into ten groups and each subgroup divided into minor subgroups. The trunks of each subgroup may be distributed according to traffic requirements in the bank terminals of first, second or third selectors and in the banks of the out-trunk secondary switches.

The selector switch I52 of Fig. 1 may be of the divided level step-bystep type disclosed for example in Patent 2,249,067 to P. W. Wadsworth hereinbefore referred to and having access over the same bank level thereof to two groups of trunks terminating in rotary out-trunk secondary switches. One such trunk is schematically shown at 516 termihating in the out-trunk secondary switch 208 of Fig. 2. Switch 2023 is of the general type disclosed in Patent 1,472,425, granted October 3'3, 1923, to Forsberg et al., but is of the non-normaling type. The switch 200 is disclosed as having access to branches of the three trunk groups including ticketing trunks H3, i M- and H5.

Each of the code-connector circuits of Fig. 3, comprises a multicontact relay such as 3621* for each identifier and a lock-out relay for each identifier and the code leads from a third of the trunks, terminating in the cross-connecting rack 35%, are arranged for extension to any identifier throu h the operation of the multicontact relay allotted to such identifier.

One of the ten trunk-identifier-connector circuits which are required to connect any one of the 2M trunks to the identifier seized to serve a connection, are disclosed in Fig. 4. Each connector circuit serves twenty trunks and is provided with a multicontact relay for each identifier and with a lock-out relay for each identifier.

To more clearly set forth the novel features of the invention, it will be assumed that the calling subscriber whose substation is indicated by the numeral it initiates a call for a toll connection to a subscribers line terminating in an oihce of the toll area to which the calling subscriber is permitted access by dialing. Upon the removal of the receiver from the switchhook, an idle line finder such as l is started in search of the calling line in the well-known manner. When the line finder has found the calling line, the usual dial tone is transmitted over the calling line to inform the subscriber that his line has been connected with a first selector I66, paired with the line finder W3, and that he may therefore commence dialing the digits of the wanted line number. It will be assumed that the subscriber desires a connection with a line whose directory number is KRA-l345 and that a ticketing trunk over which a connection to that line may be extended may be reached from the second level of the divided level selector H2 and through the rotary out-trunk secondary switch 20%. The calling subscriber upon hearing the dial tone therefore proceeds to dial the ofiice code letters K, R, A, and the numerical digits 1, 3, 4, 5. In response to the dialin of the first cifice code letter K, which has a numerical equivalent 5, the brushes of the first selector 2623 are raised to a position opposite the fifth level of its bank whereupon they rotate to select an idle selector H2 of the divided level type. In response to the dialing of the second ofiice code letter R, which has a numerical equivalent 7, brushes of switch 82 are raised to a position opposite the seventh level of its bank. It will be assumed that the switch is arranged to operate its shaft contact-s when the brushes are raised to the seventh level whereupon the switch shaft is released into its normal position whereby the second dialed code letter R is absorbed and a brush selection is made as fully disclosed in the Wadsworth patent hereinbefore referred to. In response to the dialing of the third code letter A, which has the numerical equivalent 2, the brushes are again raised to a position opposite the second bank level and are then rotated to select an idle primary trunk terminating in the second group of such bank level. It will be assumed that the trunk H6 is found to be idle and is therefore seized. Each of the trunks of this group terminates in a rotary out-trunk secondary switch 28! of the type which normally stands upon the terminals of an idle outgoing or ticketing trunk. It will be assumed that the switch 280 and other similar switches of the same group are at the time standing on'terminals allocated to the ticketing trunk H3.

When therefore the trunk H6 is seized by the switch i 2. a circuit is established from ground at switch 552 over sleeve conductor E28 of trunk H6,

over normal contacts of test jack 2 :1, through the upper low resistance winding of sleeve relay 289, over brush 253 to battery through the winding of relay 258 and in parallel therewith over the upper back contact of relay 258 and through resistance 2 i 9 to battery. A circuit in parallel with the winding of relay 2 It and resistance 219 is also established over the upper back contact of relay 269, over the interrupter contacts of stepping magnet 22%, and back contacts of relay 22l to battery through the winding of stepping relay 222. Relay 2&9 operates but the winding of relay 222 being shunted by the winding of relay 218 and resistance 25%], relay 222 does not operate. The brushes of switch 2% therefore remain in engagement with the terminals of trunk l 13 and a dialin loop is extended the calling line over the connection established therefrom, over the brushes ill and 262 of switch 280 and through the windings of the line relay (not shown) of trunk H3. In response to the operation of such line relay, an idle sender becomes associated with the trunk by a trunk finder individual to such sender and ground is connected to conductor 223 to mark the trunk. as busy. With direct ground connected to conductor 223, relay 2? now operates, if it has not previously operated, and sleeve relay 299 is held operated from such ground over brush 253 and over the upper front contacts and through the lower winding of relay 269 to battery. This busy ground is also connected to leeve conductor i2 3 to hold the previously operated line finder it? and selectors Hi6 and H2 from releasing.

With direct ground connected to conductor 223, a circuit is established over brush 2% of every other switch of the same group as switch 209, the brushes of which may be in engagement with the multiple terminals of the same trunk I I3, thence over the upper back contact of the associated sleeve relay corresponding to relay 299, over the interrupter contacts of the stepping magnet 228 of such switch, contacts of relay 221 and to battery through the winding of the stepping relay 222 of such switch. Relay 222 thereupon operates in turn causing the operation of the associated stepping magnet 226 which upon operating opens the circuit of relay 222. Relay 222 then releases in turn releasing magnet 239. Thus relay 222 and magnet 22% reciprocally control each other to cause magnet 22% toadvance the switch brushes step-by-step until an idle outgoing trunk is encountered, at which time the brush 2% will find no busy ground and the switch brushes will be arrested in engagement with the terminals of such idle trunk. In this manner all out-trunk switches whose brushes are engaged with the multiple terminals of trunk I it, are advanced to preselect other idle ticketing trunks.

Following the seizure of an idle trunk the next digit dialed by the calling subscriber subsequent to the dialing of the code digit which resulted in the seizure of the trunk, in the case assumed the thousands digit 1, is registered in the register 23!) associated with the seized trunk H3 and thereafter the remaining numerical digits dialed by the subscriber are registered in registers of the sender which has become associated with the trunk. As soon as a digit has been registered in the sender, an idle identifier for identifying the calling line and for reconstructing the called office designation is associated with the sender over an identifier-connector as described in the application of J. W. Gooderham hereinbefore referred to and the identifier is informed, through the prior operation of the trunk finder, in which main group of 100 trunks and in which twenty trunk subgroup of such main group, the calling trunk is located.

It will be assumed that the first identifier, a portion of which is represented by the dot-dash rectangle in Fig. 4, has been taken for use and that therefore a circuit is established which may be traced in part from such identifier over conductor eel, through the winding of lock-out relay dflilF allocated to the first identifier and to the trunk-identifier-connector circuit having access to the subgroup of twenty trunks in which the calling trunk is located, over the inner upper normal contacts of similar lock-cut relays allocated to the same trunk-identifier-connector circuit and to other identifiers, to ground. Relay 4MB operates, if the trunk-identifier-connector circuit has not been taken for use by some other identifier on another call, locks over its inner upper alternate contacts to ground, establishes an operating circuit for the multicontact relay ime from ground through the winding of such relay, over the inner lower front contact of relay lSSF and through resistance 463 to battery and establishes a circuit from battery through resistance id-i. over its middle upper front contact, conductor 405 and thence over a circuit not disclosed but fully described in the Gooderham application hereinbefore referred to, which extends over contacts of the identifier-connector and through the trunk finder to ground through the winding of connector relay Zlt of the calling trunk. With multicontact relay 4825 of the trunk-identifier-connector circuit and relay M3 of the trunk both operated, a plurality of control conductors are extended from the calling trunk to the identifier. It is to be noted that to serve each main group of 100 trunks, five trunkidentifier-connector circuits, of which only one is disclosed in Fig. 4, are provided.

Of the several control circuits which are established by the operation of the multicontact relay M235, there are three including conductors 435, dill and M8, which extend from terminals on the twenty cross-connecting racks, such as 225, 2 and 265 allocated to the 20 trunks of the group, to the Nos. 3, 4 and 5 multiple contacts on the multicontact relays 5 32? to filllZL and are extended over such contacts of relay stil upon its operation through the lower windings of relays @939, MB and ili of the identifier and, after the operation of relay 452 of the identifier, over the middle contacts thereof and through resistance M3 to battery. The terminals of racks such as 225, 265 and 265 are crossconnected to front contacts of the connector relays of the trunks of the ZO-trunk subgroup which have access to an identifier over the trunkidentifier-connector circuit of Fig. l, and are connectable by such relays to the brushes of the registers associated with such trunks in accordance with the allocation of the trunks of the subgroup to the three code-connectors of Fig. 3. Thus the brush 23! of register Zilllof trunk H3 is connected over the upper contacts of connector relay 2l3 of such trunk to a terminal on rack 235 connected to conductor 308 and thence over the No. 3 contacts of relay 3323, through the lower winding of relay 4% to inform the identifier that trunk H3 is one of a minor group the code leads of which appear in the multiple contacts of multicontact relays 3621 to BQZL of the first code-connector. Brush 2%! of register 260 of trunk IE4 is connected over the upper contacts of connector relay 2&3 of such trunk to a terminal of rack 245 connected to conductor 4G1 and thence over the No. 4 contacts of relay 4532B through the lower winding of relay 4H to inform the identifier that the trunk H4 is one of a minor group the code leads of which appear in the multiple contacts of relays SlZF to tiZL of the second code-connector, and brush 28! of register 28!) of trunk H5 is connected over the upper contacts of connector relay 253 of such trunk to a terminal of rack 265 connected to conductor it!) and thence over the No. 5 contacts of relay 4921*, through the lower winding of relay All to inform the identifier that trunk H5 is one of a minor group, the code leads of which appear in the multiple contacts of re- .lays 322F to 32213 of the third code-connector.

It has been assumed that trunk H3 has been taken for use and therefore upon the operation of relay N2 of the identifier a circuit is established from battery through resistance M3, over the middle contacts of relay 5E2, through the lower winding of relay 509, over the No. 3 contacts of relay MBZF, conductor 5%, the upper contacts of relay 2H3 of trunk H3, brush 23! of trunk register 23!! and the terminal of its arc to which it has been advanced in response to the digit dialed following the seizureof the trunk, over one of the ten conductors of the cable 4M, over one of the Nos. 8 to 17 contacts of operated relay illZF, to ground through the winding of one of the relays of the trunk code register, such as relays MI and 430, of the identifier. Relay 499 operates over this circuit but due to the resistance of its winding, the register relay is not operated at this time. Relay 4%, upon operating, closes a locking circuit for itself from ground through its upper Winding and over itsupper contacts to battery through the winding of relay H5 and establishes a circuit from battery through resistance 4H5, over the upper contacts of relay M2, the lower front contact of relay Q09, conductor 3M through the winding of lock-out relay 3%? allocated to the first identifier and to the No, 1 code-connector circuit, over the lower normal contacts of the look-out relays of the No. l code-connector circuit allocated to other identifiers, to ground. Relay 3001i operates if the code-connector circuit is not at the time being used on another call by another identifier, locks directly to ground over its lower alternate contacts and establishes a circuit from battery through resistance 363 over its inner upper front contact and through the winding of multi-contact relay ears to ground. When relay H5 operated, in the locking circuit of relay W9, it established a shunt around the lower winding of relay dd?) over its contacts and the inner lower contacts of relay 399 thereby reducing the resistance of the circuit previously traced through the winding of a selected relay of the register group 525 to 353 thereby permitting the operation of such relay to register the digit previously registered in the register 238 of the calling trunk.

With relay 362B operated, the code leads of the first third of the ticketing trunks in which the calling trunk is located, and which are terminated on the cross-connecting rack 35%, are extended over the contacts oi-such relay to the first identifier, assumed to be taken for use. As many code leads extend to the identifier as there are different office route appearances of all of the ticketing trunks in bank levels of selector switches. means of the cross-connecting rack 3553 the code leads of the trunks may be crossconneoted for extension to the code leads extending to the identifier whereby code leads of different trunks which appertain to the same ofiice route may be concentrated for connection to the proper :code lead terminating in the identifier.

. Multicontact relay SdQF also establishes a circuit from ground over its upper contacts and conductor Gil to battery through the winding of relay did at the identifier which, upon operating, establishes a circuit from battery through ressstance over the inner contacts of relay M2, the contacts of relay M8, the No. 2 contacts of multicontact relay 3% of the trunk-identifieroonnector circuit, over conductor 126, over the inner contacts of connector relay 2l3 of the trunk, over the terminal of the bank of switch ltd with which brush 204 is engaged, the lower contacts of sleeve relay 269, brush 265 and the terminal of the bank with which it is engaged, code lead 2%, the No. 2 contacts of multicontact relay and code lead 43l extending to the iden'nfier. Battery .potential thus connected to the code lead l3l results, as fully described in the application of J. W. Gooderham hereinbefore referred to, in causing the identifier totreconstruct the three office code digits assumed to have been dialed by the calling subscriber.

Had the ticketing trunk H3 been seized over some other selector bank level appearance in response to the dialing of some other called office designation, a sleeve relay such as 206 or 261 would have been operated and when battery potential'was applied from the identifier through the operation of relay M8 to conductor 420, such battery potential would have been con nected to another code lead individual to the trunk, such as lead 2l2 or lead 2M, terminating in the cross-connecting rack 350 and extended through the operation of muiticontact relay 302F to a code lead, such as 432 and 333, extending to the identifier.

In the previous discussion of the invention it was assumed that in response to the call, a trunk lid terminating in the out-trunk secondary switch 269 was seized and that the switch 208 was standing in the position shown with its brushes engaged with the terminals of the preselected idle ticketing trunk IE3. It will now be assumed that when the trunk H6 is seized, the

rushes of switch 2% are engaged with the ter-. minals of ticketing trunk H4. As before described, when the trunk H4 is seized over the rushes of switch 28% on the seizure of the trunk lit by selector H2, an idle sender is associated with the trunk following which an idle identifier is associated with the sender. It will be assumed that the first identifier is idle and is associated with the sender and that the identifier is associated with the calling trunk H6 through the operation of the multicontaot relay @021 of the trunk-identifier-connector circuit disclosed in Fig. 4 following which relay 2 53 of the calling trunk is operated.

It will be assumed that trunk H4 is one the code leads of which may be extended to the identifier through the operation of the No. 2 code-connector circuit and that therefore to transmit that information to the identifier the outer front contact of the connector relay 243 of the trunk is cross-connected at rack 2&5 to conductor 48?. When relay 452 at the identifier operates, a circuit is established from battery through resistance M3, over the middle contacts of relay M2, the lower winding of relay H0, the No. 4 contacts of relay 462E, conductor dill, the outer contacts of relay 2- 43, brush 28! of digit register 2% of trunk H4 and the terminal of its arc to which it has been advanced in response to the digit dialed following the seizure of the trunk, over one of the conductors of cable did, over one of the Nos. 8 to 1'? contacts of relay 4825, to ground through the Winding of one of the relays of the trunk-code register, such as relays 42! and M0. Relay MB operates over this circuit but the register relay does not operate at this time. Relay M9 upon operating closes a locking circuit through its upper winding and through the winding of relay M5 whereupon relay H5 operates as previously described to shunt the lower winding of relay M0 and to thereby permit the operation of the trunk code register relay and establishes a circuit which may be traced from battery, through resistance- MB, over the upper contacts of relay 4! 2, the lower back contact of relay 409, the lower front contact of relay 4H], conductor 3 through the winding of lock-out relay 3IOF, allocated to the first identifier and to the No. 2 code-connector cuit allocated to other identifiers, to ground. Relay EHBF operates if the code-connector circuit is not at the time being used on another call by another identifier, locks directly to ground over its lower alternate contacts and establishes a connection from battery through resistance 3E3 over its inner upper front contacts and through the winding of multicontact relay SiEF to ground.

With relay 312E operated, the code leads of the second third of the ticketing trunks in which the calling trunk lid is assumed to be located, are extended over its contacts to the identifier. Relay 13621 also completes over its upper contacts the previously traced circuit for relay M8 whereupon a circuit is established from battery through resistance 559, over the inner contacts of relay M2, the contacts of relay M8, the N0. 2 contacts of relay 62321 conductor 22% the inner contacts of relay 2 53 of the trunk H4, over the terminal of the bank of switch 263E] with which brush 2% is engaged, the lower contacts of sleeve relay 269, brush 2535 and the terminal of the bank with which it is engaged, code lead 25 the N0. 2 contacts of multicontact relay SIZF and code lead t3! extending to the identifier. The code leads extending from the trunk I M and controlled by the sleeve relays 236 and 237 thereof would in a similar manner be extended over contacts of relay SIEF to code leads such as 32 and 333 extending to the identifier.

In a similar manner, if the out-trunk switch 209 were engaged with trunk H5 at the time it was seized by the selector H2, then since the trunk is assumed to be one, the code leads of which may be extended to the identifier through the operation of the No. 3 code-connector circuit, the connection from the brush 283 of register 28% of the trunk is connected upon the operation of trunk connector relay 253 with a terminal on cross-connecting, rack 255 which is connected to conductor lirt. Therefore, assuming that the first identifier is talren to serve the call and consequently multicontact relay 492F- is operated, the circuit of relay MI in the identifier is established following the operation of relay, H2 from, battery through resistance M3, through the lower winding of relay 6i i, the No. 5 contacts of relay idZF, conductor 358, the outer contacts of relay 253, brush 289 of register 289 and the terminal of its arc to which it was advanced. in response to the digit dialed following the seizure of the trunk, over a conductor of cable ll i, over one of the contacts 8 to H of relay 4921?, to ground through the winding of one of the trunk code register relays. Relay lll thereupon. operates, locks and establishes a circuit from battery through resistance H6 over the outer contacts of relay M2, the lower back contacts of relays tilt and M9, the lower front contact of relay 31 l, conductor 32!, the winding of lock-out relay 32% of the No. 3 code-connector circuit allocated to the first identifier, andoverover the lower normal contacts of the lockout relays of the code-connector circuit allocated to the other identifiers, to ground; Relay sees"- operates if. the No. 3 code-connector cirfront, contact of relay." 3205 and through the:

winding: of relay 3221* to.- ground. 4

With relay 3122f operated, the code lea'd'siof the third third of the ticketing trunks in which the calling trunk H5 is assumed to be located, are extended over its contacts to the identifier. Relay 322F also completes over its upper contacts the previously traced circuit for relay 4 58 whereupon a circuit is established from battery through resistance M9, over the inner contacts of relay M2, the contacts of relay 418, the N0. 2 contacts of relay M5215, conductor 423, the inner contacts of relay 283 of the trunk H5, over the terminal of the bank of switch 268 with which brush 2% is engaged, the lower contacts of sleeve relay 2539, brush 2% and the terminal of the bank with which it is engaged, code lead 215, the No. 2 contacts of multicontact relay 3221 and code lead 33! extending to the identiher. The code leads extending from the trunk H5 and controlled by the sleeve relays 255 and 25? thereof would in a similar manner be eX- tended over contacts of relay 322. 5 to code leads such as 432 and #333 extending to the identifier.

It will be noted that the banks of the outtrunk secondary switch 289 are divided into three sections each of which sections provides terminals for so on trunks and that the terminals or" each section of the bank associated with brush 265 strapped together and connected respectively to the three code leads 22 i, 25 i and 2M extending over te minals of the rack 58 to the three code-connector circuits of Fig. 3. The trunk capacity of each out-trunk switch has thus been increased from twenty to twenty-one trunks. Since all of the code leads of all trunks terminate in a singie cross-connecting rack 359, it is a simple matter to shift the code leads of any trunk divided into a plurality of groups each of which is divided into a plurality of subgroups and said trunks being further regrouped into a plurality of auxiliary groups, eachv comprising one subgroup of each of said groups, control apparatus, a plurality of control conductors extending from said apparatus, switching means individual respectively to said groups of trunks, means operative upon the seizure of any trunk for operating the switching means allocated to the group of trunks in which said seized trunk is located for associating certain of said conductors with said trunk, auxiliary switching means individual respectively to said auxiliary trunk groups and means operative in response to the operation of a first switching means for oper ting the auxiliary switci ing means allocated to the auxiliary group in which the seized trunk is located for associating others of said conductors with said 'runk.

2. In a telephone system, a plurality of trunks divided into a plurality of groups each of which is divided into a plurality of subgroups and said trunksbeing further regrouped into a plurality of auxiliary groups each comprising one subgroup of each or said groups, control apparatus, a plurality of control conductors extending from said apparatus, switching means individual respectively to said groups of trunksnneans operati-ve upon the seizure of any trunk. for operating the switching means allocated to the group trunks in which said seized trunk is located for associating certain of said conductors with said trunk, auxiliary switching means individual respectively to said auxiliary trunk groups, a connecting rack common to said auxiliary switching means, control conductors individual to each of said trunks terminating in said rack, and means operative in response to the operation of a first switching means for operating the auxiliary switching means allocated to the auxiliary group in which the seized trunk is located for connecting the control conductors of the seized trunk to others of said control conductors extendirr from said control apparatus.

3. In a telephone system, a plurality of trunks divided into a plurality of groups each of which is divided into a plurality of subgroups and said trunks being further regrouped into a plurality of auxiliary groups each comprising one subgroup of each of said groups, control apparatus, a plurality of control conductors extending from said apparatus including control conductors allocated respectively to each of said auxiliary groups of trunks, means associated with each of said trunks for determining the selection of that one of said control conductors which is allocated to the auxiliary group in which said trunk is located, switching means individual respectively to said groups of trunks, means operative upon the seizure of any trunk for operating the switching means allocated to the group of trunks in which said seized trunk is located for associating certain of said conductors with said trunk, auxiliary switching means individual respectively to said auxiliary trunk groups, and means operative over the selected control conductor upon the operation of said first switching means for operating the auxiliary switching means allocated to the auxiliary group in which the seized trunk is located for associating others of said conductors with said trunk.

4. In a telephone system, a plurality of trunks divided into a plurality of groups each of which is divided into a plurality of subgroups and said trunks being further regrouped into a plurality of auxiliary groups each comprising one subgroup of each or" said groups, control apparatus, a plurality of control conductors extending from said apparatus including a control conductor allocated respectively to each of said auxiliary groups of trunks, means associated with each of said trunks for determining the selection of that one of said control conductors which is allocated to the auxiliary group in which said trunk is located, switching means individual respectively to said groups of trunks, means operative on the seizure of any trunk for operating the switching means allocated to the group of trunks in which said seized trunk is located for associating certain of said conductors with said trunk, auxiliary switching means individual respectively to said auxiliary trunk groups, a connecting rack common to said auxiliary switching means, control conductors individual to each of said trunks terminating in said rack, and means operative in response to the operation of a first switching means for operating the switching means allocated to the auxiliary group in which the seized trunk is located for connecting the control conductors of the seized trunk to others of said control conductors extending from said control apparatus.

5. In a telephone system, an incoming trunk, a plurality of outgoing trunks divided into a plurality of groups each of which is divided into a plurality of subgroups and such trunks being further regrouped into a plurality of auxiliary groups each comprising one subgroup of each of said groups, a switch in which said incoming trunk terminates having access to a plurality of outgoing trunks divided among said auxiliary subgroups, control apparatus, a plurality of control conductors extending from said apparatus, switching means individual respectively to said groups of trunks, means operative upon the seizure of any trunk for operating the switching means allocated to the group of trunks in which said seized trunk is located for associating certain of said conductors with said trunk, auxiliary switching means individual respectively to said auxiliary trunk groups, one of said control conductors being individualized to each outgoing trunk of a group over one bank of said switch and individualized to each of the auxiliary switching means over another bank of said switch and means operative in response to the operation of a first switching means for operating the auxiliary switching means allocated to the auxiliary group in which the seized trunk is located for further extending said one control conductor.

6. In a telephone system, an incoming trunk, a piurality of outgoing trunks divided into a plurality of groups each of which is divided into a plurality of subgroups and such trunks being further regrouped into a plurality of auxiliary groups each comprising one subgroup of each of said groups, a switch in which said incoming trunk terminates having access to a plurality of said outgoing trunks divided among said auxiliary groups, control apparatus, a control circuit, switching means individual respectively to said groups of trunks, means operative upon the seizure of one of said trunks through said first switch for operating the switching means allocated to the group of trunks in which said seized trunk is located for extending said control circuit to all trunks of the group in which the seized trunk is located, means individual to said seized trunk for further extending said control circuit to a terminal of one bank of said switch individual to the seized trunk, auxiliary switching means individual respectively to said auxiliary trunk groups, further extensions of said control circuit individual respectively to said auxiliary switching means and terminating in terminals of another bank of said switch which are multiplied together in accordance with the auxiliary groups in which the trunks to which the switch has access are allocated, and means operable upon the operation of a first switching means for operating the auxiliary switching means allocated to the auxiliary group in which the seized trunk is located for completing said control circuit.

ALOYSIUS J. BUSCH.

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