US1438557A - Switchboard - Google Patents

Description

R 'w; S ;C HARF.

AUTOMATIC TELEPHQNE SYSTEM. APPLICATION FILED AUG-4. 1913.

1,438,557, Patentmi Dec. 12, 1922.v

Eg' .z P5221.

' F. W.SC'HARF.

AUTOMATIC TELEPHONE SYSTEM.

APPLICATION FILED Aue. 4. I913.

Patented Dec.12,192 2 v 5 SHEETS-SHEET 2- ME ER E Fran/P Z/Z/cfzarf F. W..SCHARF.

AUTOMATIC TELEPHONE SYSTEM.

APPLICATION FILED AUG-4, :913.

1,438,557 Patented Dec. 12, 1922.

5 SHEETSSHEET 3.

q a mmlii iiim 22772255555: ZfzuezzZBr:

M Frank Z/Z/Fzfirf F; w. SCHARF.

AUTOMATIQTELEPHONE SYSTEM.

APPLICATION FILED AUGJ, I913- 1 {138,557,- Patented Dec. 12, 1922.

5 SHEETS-SHEET 4.

Z/Z/z'7z755555: v 5 Fran L" 511"; ,fizwaww z E Z F. w. SCHARF. AUTOMATIC TELEPHONE SYSTEM.

APPLICATION FILED MIG-4, 1913- Patented Dec. 12, 1922.

5 SHEETS-SHEET 5- mm mm,

m\\ um BDGMU OWN-O23: DIN

its Fours U Eli t;

FRANK w. sci-mar, or 'siouza crr'nrowa, assienonronnnnose swrrcnsonnn &

earner SUPPLY GOTEPANY, 0F CHICAGG ILLIN 0155, A CORPORATION OF ILLINOIS.

AUTOMATIC TELEPHDNE srsrnn.

Application filed August a, 1913. Serial No. reams.

iects oi? my invention is to provide an im proved and simplified auton'iatic telephone system and another object is to provide 11nproved trunk selecting apparatus; More particularly my improved trunli selecting appz'tratus looks to astructure in which a trunk prcselector is nevided whereby an truulc line is always maintained in selcc-- it o. ti 1. t coi'idition so that asimplo circuit closure oi the line in .ioiating a call Wlll effect connection between the calling line and such an.

idle trunk by means of a related mechanism which ll term trunk connector. Other features of my invention will be more particu la-rl reterred to in the ensuing specification and claims. I r

Referring now to the accompanying drawing in which all'parts are shownat normal and in which like reference characters indi cate like parts; 4 y V Fig". 1 comprising parts 1 and 2 illustrates the preferred circuit arrangement oi? an an 'tomatic telephone system embodying my invention; I

Fig. 2 illustrates a trunk selecting nism or trunk switch, consisting of a common trunk-preselector AA and a plurality associated; trunlt-connectors A;

Fig. 3 is a flarnvdewof the trunk selecting mechanism sl'iowing more particularly the trunk connectors; I

Fig. illustratesa directive trunk selector switch, also known as a first or second selector switch; and p i s Fig, 5 illustrates ifliag'raimnatically a preferred trunking; system,

Referring now more in general to the svstci 'i shown l, thepart 1 maybe placed to the lei part of part and the iircuit arrangement more" readily followed. For the purpose 0i? simplifying thcillustraconnector mechationl have shown only Suiiicient apparatus for a single connection between a calling substation B and a called substation C. The apparatus employed in such a connection consists preferably of a trunk switch com-.

prising a truhlcpreselector AA and a trunk- A, a first selector D which is a simple rotary switch an intermediate. or secondary trunk selecting; mechanism comprising a trunk-preselector A21 and associated trunk-connector A and a connector switch E which may be of any type although 1 preferably employ a two-dimension switch and have illustrated the well-known Strowg er connector. In connection with the called substation C have shown only the associated trunk-connector A The substations may be of any suitable arrangement in which a callingdevice' F is.

provided having primary contacts 1 and sec onda'rycontacts 2 so arranged that when the dial 3 is rotated and released, the contacts 1 are first closed a number of times according to the adiustment of the dial 3 and thereafter the secondary contacts 2 are closed a single time. A ringing key BK is also provided as is also a secondary key SK. The hoolcswitch aiis preferably arranged to mon'ientarily' close a ground connection to the secondary side S of the line when the r ceiver is removed and to ground both the primary side P and secondary side S when the receiver is replaced, providing the call mg key CK 1s first operated to connect the calling and releasin round.

2'2 26 i In general the operation of the system in com letin aconnectionis as follows:

Upon removal of the receiver at the calling substation B, ground connectlon 1s momentarily placed upon the secondary side of the line thereby momentarily energizing the selecting; relay' SL to cause the motor magnet MM to connect the wipers 6, 7, 8, to contacts 9, 10, ll ofthe first idle trunk which has been preselected by the associated trunkpreselector AA, which trunk terminates in a first selector switch D. As soon as a trunk is selected the test relay TR of the associated preselector AA is energized and causes its motor magnet Mil-l to operate switch AA so as to place the next idle trunk D incondition for connection to the next calling line of the group. The subscriber now by oper-j atmg the dial F causes the primary relay PR to operate the motor magnet M181 and thus advance the wipers 12, 13, 1 1 to select a set of contacts 15, 16, 17 according to the number of primary impulses transmi ted from the contacts 1. After the transmission of the primary impulses the secondary contacts 2 are closed a single time to cause the operation of the secondary relay SE and the switching magnet SV to move the side switch arms 18, 19 to their alternate position.

This secondary impulse remains for a sutficient period to cause the operation of intermediate trunk-connector A to select an idle connector E.

The subscriber now operates the dial 3 to cause the operation of connector E by vertical relay VR and vertical magnet VM and the advancement of side switch arms 118, 119, 120, 121, to the second position. The next movement oi the dial F will cause the operation of vertical relay VB and rotarymagnet ROM whereby the wipers 22, 23, 24 are extended to the terminals of the anted line.

After the subscribers have finished their conversation they replace their receivers upon their respective switch-hooks, the placing of the receiver at B effecting the energization of relays VR and of connector E and thereby causing the energization of the release magnet Bil release relays RR RR and RR in series to effect the restoration of the switches E, A D and A.

Mechanism.

Now to the mechanism which I preferably employ and referring to the automatic trunk switch of Figs. 2 and 3, 1 pro vide a plurality of trunk-connectors Ii. and a common set oi trunk contacts 9, 10, 11, and a common trunk-preselector AA. The preselector AA includes a stop 25 which may be moved into a plurality of positions correspending to the trunk contacts 9, 10, 11, by

means of the motor magnet MM The stop 25 is suitably carried by a sliding ratchet member 26 which is supported by the downwardly extending post 27, the ratchet 26 being so arranged that upon each cnergization of the motor magnet MM it ltCElVOS one vertical step and is held in its advanced position by the retaining pawl 28. Release net RM is also provided and so arranged that when its armature 29 is attracted the pawl 28 and driving pawl 30 are moved tree of ratchet 26 and held in this position by means of the locking arm 31. This arm moves upwardly and locks the armature 29 in an attracted position unti the ratchet 26 drops downwardly to normal and ens n; the-pin 31 to move the catch 31 away the armature 29 and allow it to retract. l n suitable automatic circuit breaker may be provioed for the motor magnet Mlv. l and I have shown a well-ki'iown form of such a dcvice comprising a pair of normally closed contacts 32, 33, contact 32 having a projection 32 and the Contact 33 having an insulated member 34- so arranged that when the armature of Mi l/l is attracted the laterally projecting member 35 engages the under side of projection 32 until member 35 passes beyond 32 where it engages the insulating member 3 1 and holds the contact 33 away from 32 thus interrupting the circuit for MM and allowing the retraction of its armature, whereby the member 35 rides downwardly along the upper surface of 32 to maintain the contacts 32, interrupted 08 until the armature of MM again reaches tacts 87, the arrangement being such that the wiper 36 breaks contact with one terminal 3? before it engages the next contact. l l hen the switch iiii is in its normal position the stop 25 places the lowermost or first set of contacts 9, 10, 11 in selective condition for an associated trunk-connector Wiper T5 and contact 76 are provided to effect the automatic restoration of AA when has traveled beyond its last Contact set.

Trunk-connectors A, of which there are a plurality, and preferably twenty-five for each trunk switch, comprise a carriage 39 l ted to be moved up and down on the is 10 said carriage 39 supporting a second movable device ll which is adapted to or busy wiper 8 and primary and secondary wipers 6 and '7 respectively. A downvmrdl projecting arm 12 is also carried by member -11 said arm having a plurality of holdii 3 slots 13 adapted to co-operate with the corresponding holding arm 44 depending upon the contacts 9, 10, 11 connected with, as will be hereinafter more fully explained. There 18 such an arm 44 provided for each trunkconnector A. A pivoted stop member :5 is also carried by the carriage and has a pawl 4:6 which is adapted to engage the sto 25 when the carriage 39 is raised, the position of the engaging of steps 25 and 46 determining the set of cont s 9, 10, 11, which will be connected with by the wipers G, 7, 8.

The connecting 01361; 7 i ot the wipers 8. is effected by the solenoid motor mag net 131M which is aoapted to attract its armhso whereby the arm 48 carrying the roller -19 in ves said roller upward a ainst the inclincd'plane 50 which is carried by the iber 40. this upward movement caiisii the cario be moved vertically un engage, whereby the conthe conupon the plane 50 causes right angular travel of the member ll to move the wipers 6, T. S, into on aqemcnt with he set ot. contacts 9, 1.9, 11

corresponding to the adjustment of the stop As the. memberv 4-1 travels inward, the

25 proper slot 4E3 moves into engagement with the corresponding arm 44 so as to guide the wipers in their secondary travel and hold them even though magnet MM de-energizes.

As the member 41 moves inwardly towards the contacts, the downwardly projecting arm: 4L2 moves away from the portion .45 of the be adjustedup or down. It will be understood that as soon as the wipers 6, 7, 8 engage a set of contacts 9, 1O, 11, the next corresponding preselector contact 37 ismade busy to cause the advancement of stop '25 into its next idle selecting position as will be more clearly described in connection with the circuit arrangement illustrated.

As the secondary travel of the wipers 6, 7, S is completed, the lower end of the pivoted arm 53 allows an upward movement of the catch 54: and the movement of off-normal contacts ON lto their alternate position. This catch 54 alsoholds thewipers 6, 7, 8 in their connective position until the release magnet RM isenergized to cause the arm 55 carried by armature .56 to engage the catch" I have illustrated two trunk connectors A, A andlt is to be understood that a plu-- rality of such trunk connectors Aare com mon. to each set. or" contacts 9, 10, 11. preferably provide twenty-live units A for each trunk switch;

Referring now to the first selector D, Fig. 4, it comprises a plurality of contact sets 15, 16, 17 and corresponding wipers 12, 13, 14:, said contacts 15, 16, 17 being suitably insulated from each other as are also the wipers 12,13, 14. A motor magnet MM is provided for advancing the wipers 12, 13, 14, along the contact sets 15, 16, 17 by means of a well-known form of ratchet and pawl mechanism. A retaining pawl 58 is also provided for maintaining the wipers in an adjusted position, said. pawl 58 being so ar ranged that when the release magnet RM is energized, the release catch 59 carried by the armature arm 60 hooks over the pin upon.

pawl 58 so that the retraction of thearmature oif RM causes the withdrawal of pawl 58 to allow the restoration of the wlpers.

As the wipers reach normal, the arm 61 carried thereby engages the upper end of catch moving it free of the pawl 58 and allowing said pawl 58 to again engage the wiper ratchet teeth.

lipon the first cit-normal step of the wipers of selector D, a stop 62 carried therehundred groups or a switches AAA for each 100 lines. A-

each 100 lines, it is to be understood connectors Al As already described c first l0 trunlr-connectors A are connected connect these by moves away from the pivoted arm 63 of the said switch arm 6 so that when the switching magnet SW is energized the said switch moves from its normal to its alternate position. The side switch is'preierably provided with two contact l8, l9 show in the circuit drawing, which. arms normal rest upon contacts 65, 66 and inthei te na te position upon contacts 6?, i switch D of F 42 and 1 part have used corresponding reference Cl'lkhclCtQTS to indicate like parts.

Having described in general the mechanism and circuit arrangement employed, I will now briefly describe the preferred trunking arrangement as shown in Fig. 5, in which I haveshown the first andsecond c- 1000 line s stem. 1 preferably arrange he lines in groups of .100, subdividing these groups into "four subgroups oi 25 lines one; and connect each such sub group to a primary trunlrswitch A-AA, thus providing four primary trunk he contacts 9, 10, ll. of each four primary trunk switches are multiply connected, there boll 10 such contact sets and these extend to 10 first selectors D. While I preferably provide 10 trunks and 10 first selectors D for number oi contact sets and first selectors each group of 100 lines may be varied cording to the traffic requirements.

- The first contact sets 15,;16, 1? of each group of ten first selectors 1) extends to 19 trunk-connectors A of a secondary trunk switch A AA in the first hundred group.

These trunk connectors A of the first hundred group have access to 10 connectors E 111 the first such switches D extend to the 10 secondary" trunk-switches in the secondhnndred group, the third contact to 10 secondary trunk switches in the third. hundred group, etc.

As the present arrangement for a 1000 line system, the connectors of each 100 group should be accessible from the i selectors D in each of the other hundreds groups and therei'orefor each group of i0 connectors i provide four secondary trunk switches [1 AA which four switches include 100 t the first contacts in. the corresrmnding gro .p of 10 first selectors and I then connect the next 10 trunk-co1niectors A to the 10 first selectors in the second hundred group This leaves 5 trunk-connectors on the first secondary trunk switch and I together withwthc oi the next secondary trunk switch to the first contact sets of the first selectors in the the lit)

red in general the arrangeno system illustrated, I will now cre in (lQtu the operation thereof in extent r connection between a calling 7 I and called substation.

.ssuming that substation desires to entend a. connection to called substation C whose number we will assume is the subscriber at B first close calling hey GK and then remotes receiver from its switch-hoe whereby ground is momentarily connected to conductor S and through the i. nding of selec relay Ella and normal contact 7) to bat causing the energization of SL whereby its alternate contact 71 is closed causing the ene 'iaation of the solenoid motor magnet ll e will assume at the preselector ilk; is n its normal position in which case the selector D is idle and therefore the onergization'oi hlliil mores; the wipers 6, '1", 8. into engagement with the of contacts 9., 10, 11 respecwely thus e2. the circuit of t re callto first selector D shown. is the a ii'icctor l is opera-tech contacts (EN Ad to their alternate position where i J ills e contact 70 is int rrupted to open the S11 and the magnet MM,

ose restore. The closing 201 ON extends ground y otential to the test contacts 173 4a other with the contacts 175 a? d soon as switch D is connected with, a potential placed upon its test contact ll from ground through release RE, wheresaid test by a circuit is extended through 36 and test relay T l to Jtery. is oi? a low resistance while relay i 1 is oi a conr aratively hic'h resist nc at an does not 811615521226 but of Nial is attra 36 one step into engagei out with the next test contact "T. During this advance of the gr; 336 said wiper s connection with contact on which i resting before enaxing the next COIlLRCl: anl should relay r1 interrupt its coutac 72% during this it this wiper; the motor magnet ciris still maintains; through its a l- "ontact until the magnet M li is h time the conta the wiper lass-5,55?

armature. If the said next engaged test contact 37 leads to a busy first selector D, there will of course, be a busy potential connected thereto through the relay of the associated trunk connector A and therefore relay Tlt would cause another operation of the motor magnet MM such stepping operation of the preselector AA being continued until the wiper 36 reaches a contact 87 associated with an idle first selector D. Should all of the contacts 37 have a busy potential connected thereto, the wiper 36 continues beyond the last contact 3? at whi h time the release wiper 75 engages the grounded contact 76 establishing an energizing circuit for the release magnet RM and thereby causing the restoration oi the preselector AA to normal, as already described in connection with the switch drawing Figs. 2 and 3. Such a selecting operation of the trunk preselector AA is continued until the wiper 36 engages an idle contact 37. v

t is, of course, to be understood that sufficient trunking equipment is to be provided to take care of the tratlic at the busiest period.

As a next step in extending the connecti-on the calling device F is operated to effect three closures of the primary contact springs 1 whereby ground is momentarily connected to the primary conductor P three times, these three ground connections effecting three operations of primary relay PR over a circuit including said primary conductor P, wiper 6 and contact 9, arm 18 and normal c itact 65 through the winding of PR to battery. Responsive to the three operations of PR alternate contact 77 is closed three hues thereby causing three operations oi motor magnet MM whereby he wipers l2, 18, Li ot first selector D advance into onga 'ement with contacts 15, 16 17, leading to a secondary trunk switch in the third hundred group.

After the transmission of the primary impulses, a single secondary impulse is trans mitted by contacts 2 whereby ground is momentarily connected to the secondary con ductor S through wiper 7 and contact 10, arm 19 and contact 66, and the winding of secondary relay SE to battery. Relay SR therefore closes its alternate contact 78 causing the energization of the switching magnet Sil whereby said switch arms 18, 19 are moved into their alternate position into connection with contacts 67, 68.

Although I have also shown a secondary key SK, I preferably arrange the calling device F so that the secondary impulse is of sufficient period to remain connected to the secondary conductor after the side switch arms 18, 19 have operated, so that this secondary impulse will extend over wiper 13 and contact 16, selecting relay SL and ON to battery to cause the energization of SL This effects the closure oi alternate contact RR of trunk- connector contacts 8,11,the

low resistance winding ot. contacts M and 17, low resistance relay BB contacts 8 and 11 contact 37 and the wiper 36 through the winding of high resistance test relay llt to battery The current in this circuit is su'liicient to causethe energization of TR but not of the release relays RE, BB and R3 The energization of Tlt causes the operation of the 'trunlr-preselector AA? i manner as described in connection with I t Connection has now been extended from the calling substation to an idle connector E in the third hundred 910111) of lines, which group includes the linevof substation 3 13. The subscriber now operates calling device F to transmit tour impulses through primary conductor P through the winding of the vertical relay VB; to battery. Relay Vll theretore is operated four times effecting tour closures of its alternate contact 81 whereby tour impulses are transmitted through the vertical magnetVM traced from ground at said alternate contact 81, normal contact 86, j

side switch arm'l18 and its normal contact through the winding ofVlVl to battery. The vertical magnetVM is therefore operatedto step the wipers 22, 23, 24: oppositethe fourth row of contacts 82, 83, at which now includes the terminals of substation 343. p

After the transmission of thelfour primary impulses, a single secondary impulse is transmitted over the secondary conduc tor S and through the rotary relay of connector Etc battery. Belay RUR- is operated single time toclose its alternate contact 8? whereby a circuit is closed through. private magnet P lZ'andr-side switch arms 118, 119, 120 and 121 are moved to their intermediate position in a well-known Thesubscriber at B now operates the call ing device F to transmit three primary lll lr" pulses over the primary conductor P and through the vertical relay to battery whereby three primary impulses transmitted. through the rotary-magnet ROM? traced from ground. at said alternate contact 81 normal contact 86,'saijd switch arm 118 and its middle contact,- through the winding of RQMto battery. Magnet ROM therefore operateswipers 22, 23, 24 teen 7 nation.

gage the'third set of contacts 82, 83, 84,

which are the terminals of the line of substation 3 13,

After the transmission of the. threelast primary impulses, a secondary impulse is again transmitted over the secondary conductor S and through the winding of rotary relay ROB to battery. A circuitfor private magnet PV is thus againestablished from ground at alternate contact 87 and through the winding of PV to battery causing its energization and the movement of side switch arms 118, 119, 120 and 121 to their third position, thatis, it the wanted line is idle, which we will assume it is.

The connection having been completed between the callingand called lines, the subscriber at substation D depresses the ringing key ltliwhereby. ground is connected to the primary conductor and through the vertical relayVR tobattery, causing; its energi- Alternate contact 81 of VB is therefore closed establishing an energizing circuit tor ringing relay RI through the side switch arm 118 in itsthird contactposition, whereby said relay R1 is energized to connect the ringing generator G in bridge of the terminals of the called lineand to etfectthe operation ofthe callgbell at substation C The'subscriber at substation G in response to the call, removes his receiverfrom its switch-hook thereby completingv the conversational circuit which. is traced over the. heavily marked conductors,talking battery beingsupplied "from the substations Band C.

' Releasing.

After the subscribers have finished their conversation they replace their receivers upon their respective switch-hooks thereby momentarily grounding both sidesolt the line but in the case of the called substation this has no 611605 upon the release. At the calling substation though, this grounding of the two sides of the line extends ground connection over the primary and secondary talking conductors and thrdugh the vertical and rotary relays of the connect-or E to battery causing their energization. Contacts 89, 90 are thus closed establishing a release circuit for the diiferent switches traced from battery through the winding of release magnet EM contacts 89, 90, conductor 91, contact 11 and wiper 8 release relay RR, contact 1'? and wiper 14, release relay BB contact 11 and wiper 8, and the winding of, release relay to ground. The energizathe interruption of the circuit for EM and its ensuing de-energlzation, the latch 5a is to normal in a well-known the secondary trunk connector A and upon releasedfrom the arm 53 thus allowing the restoration of the wipers 6 7 8 Upon energization of BB of first selector D, circuit is closed through its release magnet RM which attracts its armature and upon de-energiza'tion w'thdraws the retain ing pawl 58, shown in Fig. 1, allowing restoration 0t wipers 12, 13, 14.

Upon energisation of RR of primary trunk-connector A, circuit is closed through release magnet RM which is energized and de-energiz'ed, allowingrestoration of the wipers 6, 7, 8', to normal.

The restoration of switch A to normal removes the busy potential from the con nector test terminal 173 thereby placing the line 01" substation B in an idle condition once more. The disconnection of wiper 8iro1n contact- 11 also removes the busy potential from the corresponding first selector D whereby it is again in selectable condition byany ofthe four associated preselectors AA or one hundred trunkeconnectors A.

The removal of busy potential from the test contact 17 c t-first selector D and thus also from wiper 8 and associated test contact 1.1 of trunk connector 23. places the connector E in a selectable condition.

Called Zine busy. i

In the connection previously described it was assumed that the called line was idle at the time connection was made therewith, and I will now describe the operation of the system when the connector E connects with the terminals of a busy line. In such case the operation is the same as that previously described up to the transmission of the last impulse, at-whiclrtime assuming; the line 3 13 isbusy and its test contact 8% has a ground or busy potential connected thereto, when the private magnet PV is energized responsive to the last secondary impulse, a circuit is traced from said grounded test contact Set through wiper 24:, side switch arm 121 and its middle contact, alternate Contact 88, and the winding of Bill to battery, causing); the energization of EM and the release of connector E. The calling subscriber of course, up to this time is not awarefo't the busy con dition of the called; line and theretore operates the ringing key EH in the usual manner thus operating vertical relay VB and thereby the vertical magnet VM, stepping the switch E offnormal and closing the vertical ofii normal contact VON. A characteristic busysignal from-busy back BB is therefore connected to the talking conductors and the calling; subscriber, hearing this signal, is aware that the called substation is busy and replaces the receiver upon its switch-hook grounding. both the conductors S and P. Thegrounding: of these conductors of courseoperates: relays VB and ROB, whereby the release relays; and: release magnets of the meat-5 2' switches used in establishing connection are operated in a manner as previously described.

Although l have chosen to illustrate my invention in a 1000 line automatic telephone system, it is to be und rstood that the capacity of my invention is by no means limited to 1000 lines, as other dircctively controlled selectors as D and associated automatic trunk switches A as may be provided between the secondary trunk switch and connector Or the connectors may be connected lircctly to the terminals 0, 10, 11 of the primary trunk switch. it will also be apparent that many changes and modifications in the circuit arrangement and apparatus construction may be made, and therefore I do not desire to be limited to the particular matter shown and described but aim to cover all. that which comes within the spirit and scope of the appended claims.

lVhat I claim new and desire to secure by United States Letters Patent is:

1. A trunk switch for telephone systems comprising a plurality of trunk connectors, trunk lines common to said trunk connectors, a set of contacts for each trunk common to the connectors, a trunk preselector common to said trunk connectors for automatically maintaining the contact set of an idle one of said trunks in connective condition, a selectinn relay for each of said trunk tonnectors, and a motor magnet and mechanism controlled therebv responsive said selecting relay for op .ting the associated trunk connector to connect with the contact set of that trunk which is in connective condition.

2. trunk svitch for telephone systems comprising a plurality oi trunk con ctors, trunk lines common to said trunk connectors. a sii'iggle set of terminals for each o said trunk lines appearing before said trunk connectors, a trunk preselector havinp; terminals multiply connected to said trunk line terminals, automatic means for operating said preselector to maintain the contact set of an idle one of said trunks in connective condit on including multiple t minds, and means included in each of d trunk connectors for operati the associ vd trunk ctor to co mect with he c act set of condition.

trunk w c telephone systems cor prisin a plurality of trunk connectors, trunk li (3111111011 to said trunl; ci'mncctors, single set ol terminals: for each 0 t said trunk lines appearing before said trunk connectors, a trunk preselectoi' having terminals nuiltiply connected to said trunl: line terminals, automatic means for operatin a said preseico tor to maintain the contact of an idle one of said trunks in connective condition including said multiple terminals, a selecting 'relay for each of said trunk connectors, and

motorniagnet and mechanism controlled thereby responsive to saids'electing relaytor trunk-preselector common to said trunlr com nectors for .maintainins the contact set of an idle one of said trunrts in connectivecondition, and means includedin each of said trunk connectors effective npon initiation of a call over the associated line to cause the associated trunk-connector to connect with the contact set of that trunk which is in connective condition,

5. A telephone exchange system comprising telephone lines, individual trunk-connectors for said lines, trunk lines common to said trunk-connectors, a set of contacts for each trunk common to the connectors, a

trunk-preselector common to said trunk connectors for automatically maintaining the contact set of an idle one oft said trunks in connective condition, line or selecting relay for each of said trunlcconnectors energized.

responsive to a call over the associated line, and-a motor magnet responsive to said selectinp,- relay and mechanisn. controlled thereby for operatingthe associated trunk connector to connect with the contact set of that trunk which .18 in connective condition.

6. A telephone exchange'system comprise ing telephone'lines, individual trunk connectors for said lines, trunk, lines common preselector having terminals multiply connected tosaid trunk lineterininals, auto,

matic means for operating said preselectoi' to maintain the contact setfof an idle one of said trunks in connectivecondition includingsaid multiple terminals, and means in eluded in each of said trunk connectors effective upon initiation of a call over theassociated line to cause the associatedtrunk connector to connect with the contact set, of that trunk which is in connective condition.

7. A telephone'e' rchange system comprising telephone lines, individual tru nlccon nectors tor said lines,,trunk lines common to said trunk connectors, a single set vof terminals tor each of said trunk lines appeering before said trunk connectors, atrunlr preselector having terminals multiply connected to said trunk line terminals, automatic means tor operating said preselector to maintain theicontact set of "an idle oneol said trunks in connective condition, l

automatic means including said multiplex hti 71A.

sive to a call for the associated line, and a motor magnet and mechanism controlled thereby responsive to said selectingrelay toroperating the associated trunk connector to connect with the contact set that trunk which isin connective condition,

8. A telephone system comprising te ephone lines, first selectors and connectors, au-

toinaticswitching devices for interconnecting said lines and first selectors, calling de-- vices at the'sulostations of said lines for operating the first selectors and connectors, and "interposed non-directive automatic switching devices also responsive to said calling devices for interconnectingsaid first selectors and connectors, each of said slectors being provided with a number of said non-directive automatic switching devices for its individual use.

9.,A telephone system ffOillDZlS'lDQ, telephone lines, first selectors and connectors, calling devices at the substations of said lines for operating the first selectors and connectors, automatic switching devices irres'ponsive tosaid calling devices for intcrconnecting said lines and first selectors, interposed non-directive automatic svitcliing devices "responsive tosaid calling devices when operating; said first selectors, for interconnecting said first selectors and con-- nectors, ringing means for said connectors, and a ringing key at the calling suhstation for operating said ringing means to connect ringing current to the called substation eachtime saidlrey is operated.

10. A telephone system comprising telephone lines, first selectors and connectors,

calling devices at the substations of said lines adapted for transmitting primary and secondary impulses for operating: the first selectors and connectors, automatic switching devices irresponsive to said calling devices for interconnecting; said lines andfirst selectors, interposed non-directive automatic switching devices responsive to asecondary impulse from said calling devices when opcrating said first selectors, tor intercoiniectingsaid first selectors and connectors, au-

dible busy-back signaling means for said connectors, and means for automatically restoring'said connectors when said connec tors are connected to busy lines to connect said busy-back signaling means in circuit with the calling lines.

1.1 A trunk switch for telephone syste comprising a plurality of trunk connector switches, wipers and motor magnets for each of said connectoraand mechanism con trolled by said motor magnets for operating said trunk connectors independently for con nectinp; to a common set olttrunk cont-act's.

12 A trunk switch for telephone systems comprising "a plurality of trunk connectors, sets of contacts common to said connectors, a preselector having operating positions corrank switch comprising plurality o indiddual-select each having contact ;=-.-:akers and driving mechanism therefor, a set of. contacts comn'iori to said contact makand means whereby any selector may seize said contacts to the exclusion of the other selectors.

15. ll. tiL switch comprising a plurality ial selectors each. having contact makers and driving mechanism. therefor, sets of contacts common to said contact makers, and means whereby any driving mechanism is controlled tor operating its contact makto connect with any of said contact sets.

16. it trunk switch comprising a plurality .idual selectors each having contact ers and driving mechanism therefor, sets of contacts common to said contact makers, means whereby any driving mechanism is controlled for operating its contact makers to connect with any of said contact sets and means to prevent any other selector from seizing contact set already connected with.

17. A trun switch comprising a plurality of individual selectors each having contact makers z ving mechanism therefor, sets of contacts co non to said contact makers, stop D'EGClZRl'llSlll having stop positions for the selectors corr sponding to the contact sets, and means for operating said stop mechanism. i

18. A trunk switch comprising a plurality of individual selectors each having contact makers and driving mechanism therefor, sets of contacts common to said contact makers, stop mechanism having stop positions for the selectors corresponding to the contact sets, and means for advancing said stop mechanism each time a contact set is seized. Sh trunk switch comprising a plurality i-dual selectors each having contact and d1 i ing mechanism there-tor, sets acts common to said contact makers, ines leading from said contact sets, a prose. ctor for maintaining the contact set of an idle trunk in connective condition, and means whereby when a selector seizes said idle contact set said preselector is advanced to maintain the contact set of the next idle trunk in selectable condition.

20. n trunk switch comprising a plurality of individual selectors each having contact makers resting in their normal position, contact sets for said contact makers, conductors leading from each contact set, driving mechanism for each selector for moving its associated contact makers to any one of said sets of contacts, a preselector for maintaining an idle trunk in connective condition, and means for operating any oi said driving mechanisms to advance their contact makers from their normal position into engagement with the preselected contact set.

21. A telephone system comprising telephone lines, a selector individual to each line provided with contact makers, sets of contacts adapted to be engaged by the contact makers of any of said selectors, trunk lines leading from said contacts, d 'iving mechanism for each selector for moving its associated contact makers to any one of said sets of contacts, and a preselector normally maintaining the contact set oi an idle trunk in connective condition.

22. A telephone system comprising telephone lines, a selector individual to each line provided with contact makers, sets of contacts for said contact makers, trunk lines leading from said contact sets, driving mech anism for each selector for moving its associated contact makers to any one of said contact sets, a preselector maintaining the contact set of an idle trunk in connective condition, and means for operating the driving mechanism of any of said selectors to advance their contact makers from their normal position to connect with the preselected contact set and means: for operating any of the driving mechanisms.

23. A telephone system comprising telephone lines, first selectors and connectors, automatic switching devices individual to the lines for interconnecting said lines and said first selectors, calling devices at the substations of said lines for operating the first selectors and connectors, interposed non-directive automatic switching devices provided with individual active contacts, and motor mechanism' for said last devices for moving said active contacts to thereby interconnect said first selectors and connectors, said connectors comprising a partof the talking circuit of said telephone system. 24:. A telephone system comprising telephone lines,-first selectors and connectors, automatic switching devices for interconnecting said lines and said first selectors, calling devices at the substations of said lines for operating'the first selectors and connectors, interposed progressively movable non-directive automatic devices provided with active contacts, each of said last devices being for the individual use of a particular selector, and motor mechanism for said nondirective devices for moving said contacts into connection with preselected,connectors, said connectors comprising a part of the talking circuit of said telephone systemv and connectors, each of said first selectors being provided with one of said non-directive devices for its exclusive use, and a common mechanism for preselecting the connectors that the selectors connect with.

26. A telephone system comprising telef phone lines, first selectors and connectors,

automatic switching devices for interconnecting said lines and first selectors, calling.

devices at the substation of said lines for operating said selectors and connectors, interposed non-directive automatic switching de-c vices also responsive tosaid calling devices for interconnecting said selectors and connectors, each of said selectors being provided with a plurality ofsaid non-directive devices, for its exclusive use, and common mechanism,

for selecting the connectors for said non-directive switchlng devices.

27(A telephone system comprising tele phone lines, a first selector and a pluraiity of connectors,'automatic switches for pre-selecting said first selectors and said connectors, automaticvmeans for connecting one of said lines to saidfirst selector, interposed progressively movable non-directive automatic switching devices provided with movable contacts,and motor mechanism for said non-directiveswitching devices for moving said contacts, thereby connecting said selector to one of said connectors;

QSZA telephone system comprising telephone lines, a first selector and aplurality of connectors, switching means for connecting a calling one of said lines to said first selector, interposed non-directive progressively movable automatic switching devices provided with active contacts, each of said non-directive devices being for the exclusive use of a particular selector, stationary contacts for said connectors, motor mechanism for moving said active contacts into connection with an idle one of said connectors, and

common mechanism for selecting the con-- nected with connector. 1

29. A telephone system comprising telephone llnes, first selectors and connectors, automatic switching devices for connectlng said lines and first selectors, calling devices at the substations of said lines for operating said first selectors and connectors, and in-',

of connectors, an automatic switchingdevice connectors.

for connectingsaid first selector to a cal'lhr; one of said lines, and interposed non-directive progressively movable automatic connecting devices individual to said selector for connecting said selector ,to one of said 31. A telephone system comprising telephone lines, a first selector and a plurality of connectors, an automatic switching device for connecting said first selector to a calling one of said lines, interposed automatic switching devices individual to said selector for connecting said selector to said connectors, and common mechanism for selecting connectors. i

32. A telephone system comprising telephone lines, a first selector and a plurality of connectors, an automatic swltching device for connectingsaid first selector to a calling one of said lines, and interposed automatic switching devices for the excluslve use ofsaid selector for connecting said selector to said connectors.

33. A telephone system comprising telephone lines, a first selector and connectors, an automatic switching device for connecting a calling one of said lines to said selector, calling devices at the substation of c said lines for operating said first selector and connectors, interposed automatic switch' ing devices individual tosaid first selector for connecting said first selector to said connectors. c a I 84:. A telephone system comprising telephone lines, a first selector and connectors, automatic switching devices for connecting a calling oneof said lines to said selector, calling devices at the substation of said lines for operating said first selector and connectors, interposed automatic switching devices individual to said first selector for connecting said first selector to said connectors, and, common mechanism for preselecting connectors. I t

35. A telephone system comprising telephone lines, a first selector and connectors, an automatlc swltching device for connecting a calling one of said lines to said selector, calling devices at the substation of said lines for operating said first selector and connectors, interposed non-directive progressively movable automatic switching devices for the exclusive use of said first selector for connecting said first selector to said connectors.

36. A telephone system comprising tele- -phone lines,a selector switch and a plurality of connectors, means for connecting a calling one of said lines to said selector switch, a calling device at the substation of said callingline for directively controlling said selector, a plurality of non-directive automatic switching devices, individual and accessible to said selector, and means for operating one of said non-directive switching devices for connecting with one of said connectors.

A telephone system comprising telephone lines, a selector switch and a plurality of connectors, n cans for connecting a calling one of said ines to said selector switch, a call device t the substation of said calling line for diractively controlling said se iectcr, a plurahty ct non-directive automatic switching devices ind idual and accessible to said selector, means for operating one of said non-directive switching devices for connecti with one of said connectors, and mean for preselecting connectors.

A telephone system comprising tele phone lines, a first selector and a plurality oi connectors automatic means for connectt selector to a cailing one or said and an interposed non-directive vely movable switching device for aclusive use oi said selector for connecting said selector to one of said connectors.

39 A telephone system comprising callingz and called telephone lines, first selectors and connectors, automatic switching devices indi "dual to the lines for interconnecting said lines and said first selectors, calling devices including dials at the substations of said lines for operating the first selectors and connectors, said automatic switching devices operative independently of said dials, interposed non-directive automatic switch ing devices provided with motor mechanism for interconnecting said first selectors and preselected connectors, audible busy-back lines,

means for sale connectors, and means for 1111- tomstically restoring said connectors when connected to busy called lines to connect said busy-back means in c' c-uit with the calling lines.

40. in a telephone system, a series of nonnuinerical switches, a second series of numerical switches to which said first series weeps? is adapted to extend a connection, and a third series of switches to which said second series is adapted to extend a connection, each switch of said second series having a plurality of switches on said third series which are individual to each of said second series oi switches;

41. In a-telephone system, a series of nonnumerical switches, a second series of numerical switches to which said first series is adapted to extend a connection, and a third series of switches divided into groups to which said second series is adapted to extend a connection, each switch of said sec ond series having an individual switch in each group of said third series of switches.

42. In a telephone system, a plurality of lines, a numerical switch for electing one of said lines, a non-numericalpreselecting switch associated with each of said lines, other lines, means for operating said nonnuinerical switch to connect with one of said other lines, said numerical and non-numerical switches having selective movement in a single plane.

43. In a telephone system, a plurality of lines, a numerical switch for electing one of said lines, a non-numerical preselecting switchassociated with each of said lines, other lines, means for operating said nonnumerical switch to connect with one of said other lines, said numerical switch having rotary motion in selecting one of said first lines, and a solenoid motor magnet for said non nunierical switch for movingthe same in a single plane to connect with one of said other lines.

Signed by me at Sioux City, county o f" FRANK W. SCHARF. Witnesse's:

MAX MoGAN, L. BRIDWELL.

Images