US1695049A

US1695049A - Telephone-exchange system

Info

Publication number: US1695049A
Application number: US55652A
Authority: US
Inventors: Jacobsen Emil; Arthur B Sperry
Original assignee: American Telephone and Telegraph Co Inc; Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1925-09-11
Filing date: 1925-09-11
Publication date: 1928-12-11
Anticipated expiration: 1945-12-11

Description

Dec. 11, 1928. 1.6951049 E. JACOBSEN ET AL TELEPHONE EXCHANGE SYS TEN Filed Sept. 11, 1925 3 Sheets-Sheet 1 [77 7/7 Jacofikser r. A, m WA/wm 6." p y- Af/M I. I 7 H12 Fig.2

'Dec, 11, 1928. 1,695,049

E. JACOBSEN ET AL TELEPHONE EXCHANGE SYSTEM Filed Sept. 11, 1925 s Sheets-Sheet 2 IIHI- 9 4 w m 9 a 6 R. 1 t m cuNEiSl s 3 M nms ww E GD sCt Bum O CNd Am JPN .EF m m ca 2 9 1 I .l 3 D 8% Patented Dec.- 11,1928;

) UNITETDSTATES Al l NT OFFIC EMIL'JAGOBSEN, or roar WASHINGTON, Ann ARTHUR 13.; srnnnY, OF: Nnw YoRK, i v

. N. Y.; SAIIJ J-AGOBSEN ASSIGNOR TO AMERICAN TELEPHONE TELEGRAPH COMPANY, A GORFORKTION OFITE'W YORK, ,AND; SAID PERRY 'ASSIGNOR 'IO'WE ST- nan nnncrmc eonrnnr, or NEW YORK.

e Application filed September This invention relates to telephone systems and more particularly to circuits for automatically extendlng connectlons to lnterce tim erators ositions.

station, each comprising oneof the talking" conductors and a ground lead. In such areas,

, when it becomes necessary to add additional equipment to care for the growth of the exchange, it is desirable and more economical to install equipment of a'more modern character which is designed to function over tullmetah lic circuits extending to the substationsgthereby eliminating the ground. return. When such modern equi nnent is added to an existtus may function together so that all subscribers may have access to each others lines and to the several operatorspositions."

The object of this invention is therefore to provide an improved means for intercepting calls from a dial station ma two-wire office to a dial station in athreewireofiice.

automatically operabie means in anintercepting operators cord circuit to preventoperation of call charging apparatus. 7

Fig. 1 of the drawings shows at 1t's upper left hand corner a subserlbers statlonin a two-wireofiice connected to a line switchLS and a two-wire first selector FSwhichin turn has access to arepeater R. The repeater is extended to the three-wire oflice by the trunk designated by

conductors

134 and 135 which terminate in the first trunk selectors.

Fig. 2 showson its left hand side a connector C in a three-wire otfice whichhas access to the interceptingoperators trunk IOT. An intercepting operators cord circuit is shown atIOG on the right hand side of thisfigure. f

1 Fig. 3 at its upperleft handcorner' shows a manual operators cord circuit OC.- The outgoing trunk OT extending between the two-wire office" and the three-wire oflice is 111g exchange, it becomes'necessary topro- INCQRPQRATED, OF llEW YORK, N. Y., ACORPORATION' rnLnrnonn-nxonanen sysr nn.

11, 1925. 'seriai'no. 55,652. 1

designatecl' by 834: and 335ywhich is inturn connected to the first selector FTS. i e

Fig. 1 isj'a diagram showing the manner" in whichthe several figures may-be combined to completely disclose the invention; Y t

Of the two embodiments ofytheinventi'on. illustrated in the above figures the one shown in Figs. 1 and 2 is preferred. i A'clearer idea'of'the operation ofthe inven tion may be had from the following detailed description. r

:When subscriber 100 removes there'ceiver. from the switchhoolg-line switch LS operates and closes spring combination 102 in a manner Wellknown in the art. Relay 104 is a I polarized r lay and does not operat eat this" timeg as itxis used forcontrolling the message i register circuit and is underthecontrol of. the called party. Subscriber 100 now oper-T7 ates diallOlQ Relay 109 inithe'fi'rstselector FS"operates over a circuit from ground through the left winding otrelay109youter left back contact of relay 107,.tip of spring combination'102, dial 101, subscribers 10015,"?5'

I I winding of relay 109 Rela-y 109 fo'llowsthe A feature of the inventionis inithe provision of means'in trunk circuits respon'slveto I and 113 to step the brushes 110, 111 and-.112

to'thcdesired group ofban'k terminalshas35 been-omitted from the disclosure "for the sake: of'brevity. As soon as the primary move I nient of the switch is completedja circuitisf established in the usual well-known manner for the secondary magnet 108' whichqfunc tions to step the brushes in search of an'idle" trunk-in the selected group. VVhen'an idle trunk is found the "stepping magnet 108' ceases to operate and relay 107 operates and closes the tip andlring leads through to conductors "117 and 118 ofifepeater' B. When brushes 110, 111 and-112 make contact with p v terminals 120, 121 and 122 "acircuit is closed from battery'through the winding ofrelay j" r 116 inner right back" contact 015 relay 12 913 001, 7 1

terminal 122; brush 112, right front contact of relay 107, to'gro'und on the front contact o ff I relay 113. Relay 116, operated, locks to ground over the circuit hereinbefore traced and prepares through its inner right front contacta circuit for relay 129 which is completed later. Another circuit is closed from battery through the left winding of relay 115,

inner right back contact of relay 1233, con- 7 doctor 118, terminal 121, brush 111, inner left front contact of relay 107, winding of relay 104, through the spring combination 102, subscl'ibcrs station 100, dial 101, spring combination 102, outerleft front contact of relay 107, brush 110, terminal 120, conductor 117, inner left back contact of relay 123 to ground through the right winding of relay 115. The operation of relay 115 closes an obvious circuit for the operation of relay 124. Relay 124 at its inner right front contact also conneets groundto the holding circuit of relay 11 6and over terminal 122, brush 112, right front contact of relay 107, replacing the ground supplied by relay 113 before relay 1 113deener izes following the cutting throng of the ta ing conductors of switch FS. lVhcn the dial 101 at the subscribers station 100 is operated relay 115 releases in response to the interruptions of its circuit and transmits pulses over a circuit from ground on the outer right back contactof relay 123, right back contact of relay 115, left front contactof relay 124, conductor 134, inner left back contact of relay 132, through the winding of vertical relay 130 of switch S.

heoperation ofvertical relay 130 closes a circuit from groundon contact 152 through the winding of vertical magnet 144 to battery on the back contact of release magnet 1 86, thereby operating the vertical magnet a certain number of times accord in g to the digit dialed and causing brushes 140, 141, and 142 to move upward. Upon the first release of relay 115 with relay 124, operated, a. circuit is closed from ground on the left back contact ofrelay115, outer ri ht front contact of relay 124, to battery tlirough the winding of relay 126. Relay 126 being slow to release j does not release upon the opening of the circnitby the operation of relay 115 While following the dial pulses. The operation of relay 126 closes'acircuit for the operation of relay 127 from ground on the outer right back contact of relay 129, inner right-front contact of relay 126 to battery through the Winding of rela 127. vThe operation of relay 127 closes an o viouscircuit for the operation of relay 128. Relay 128, operated, looks over a circuit from ground over the inner right contactof relay 124, normal contact of relay 125 to battery through the right front contact and Winding of relay 128.

When dial 101 returns to normal, relay 115 remains operatedholding relay 124 operated but the operating circuit for relay 126 is opened, allowingit to release. The release of relay 126 opens the circuit for relay 127,

and, as relay 127 is slow to release, its contacts will still be closed after the contacts of relay 126 are opened. Therefore, a circuit will be closed for operating rotary relay 131 from ground on the outer right back contact of relay 129, inner right back contact of relay 126, outer right front contact of relay 127, conductor 135, off-normal contact 199, outer back contact of relay 132 to battery through the winding of rotary relay 131. The operation of relay 131 closes a circuit from battery at the contact of release magnet 136, Winding of private magnet 137 .to ground on contact 153 of relay 131. The operation of magnet 137 closes a circuit from battery winding of rotary magnet 138 and winding and outer front contact ofmagnet137 through the winding of relay 133 to ground over test brush 142. The circuit of magnet 138 is thus maintained and the switch brushes are advanced in a hunting movement until an idle trunk is found when magnet 137 will deenergize and open the circuit of rotary magnet 138. Relay 133, which was included in the circuit of magnet 137, doesnot receive sufiicient current in series with n'iagnet 137 to operate at this time. A circuit is now closed from battery through the rotary magnet, winding of relay 132, secondary olfnormal spring combination 139, to ground on the primary off-normal spring combination 143. Relay 132 operates and closes

conductors

134 and 135 through to brushes 140 and 141. V

The connection has now been completed toconnector C whichhasbeen found idle and brushes 140, 141 and 142 are resting on contacts 210, 211 g and 212. closed is substantially identical with thoco n nector switch shown in the patent to'Falcs The connector dis- 1,186,563 and operates in a manner fully disclosed therein. 1 It is'of course obvious that any well-known connector switch of the threewire type might be used in place thereof. A circuit is partially closed from battery through the middle back contact of spring combination 219, winding of vertical relay 201, terminal210, brush 140, inner front contact of relay 132, conductor 134 left front contact of relay 124, to the right armature of rel ay 115. 101 todial the next digit, relay will release,completing this circuit through its right back contactto ground at the outer right back contact of relay 123 and operating relay 201 When subscriber 100 operates dial telephone circuit.

241 thereby connecting ringing current for operating relay 125 over a circuit described below. The operation of relay 253 closes anobvious circuit for relay 258 and relay right front contact of relay 254 to battery through the winding of relay 251 thereby operating it. Relay 251 locks to ground on the right front contact of relay 252 over an obvious circuit. The operation of relay 251 connects the tip side of plug 241 to conductor 263 and thence to the intercepting operators Through the release of

relays

260, 253 and 258, following the deenergization of relay 257, relay 254 has released and a circuit is now closed from ground on the back contact of relay 257, outer rightback contact of relay 254, outer right front contact of relay 251, back contact of relay 250, to battery through the-winding of relay 256. Relay 256, operated, lights lamp 258.

As soon as relay 251 has operated the tip and ring conductors are extended to the bridge 250 across the operators cord circuit. Relays 216 and 217 operate in series with this bridgeand the relay 209 is thus prevented from reoperating.

The operator may insert the plug 241 during a ringing interval, namely, during the time the relay 209 is operated. In this case the relay 257 is operated in a circuit from the grounded generator 214 to the left front contact of relay 209, wiper 203, brush 220, terminal 230,and thence as previously traced to ground at the contact of relay 252. The re-' lay 257 operates in series with the generator 214. If the relay 254 operates before the next silent interval, relay 257 is maintained by a circuit leading through the condenser in parallel with the inner right contact of relay 254. When the next silent interval oc curs, relay 257 releases and from this point the circuits function as hereinbefore de scribed. It will be noted that if relay 217 has operated in series with relay 257 ,it is released by the operation of relay 254 to release in turn the relay 129 to prepare the circuit of relay 125 before current is transmitted from the source 261." i

On a call to a subscriber, a circuit is closed through the subscribers loop to operate re lay 216. Belay 216 connects ground to conductor-210, through the winding of relay 201, and thence to conductor 134, left front contact of relay 124, rightfront' contactof relay 115, outer right back contact of relay 126,

inner right front contact of relay 116, windin of relay 129, outer right back contact of re ay 127, to conductor 135, and thence to battery through relay 202. Relay 129 is thereby operated to close a circuit from ground on the left front contactsof relays 128 and 129 to battery through the winding of relay 123. The operation of relay 123 reverses the circuit hereinbefore traced through relay 115 thereby supplying battery over conductor 117 instead of over conductor 118, causing message register 106 to operate and charge the call. a

As there isno charge made for a call to an intercepting operator, it is desired to prevent message' register 106 from operating. This is done by means of slow-to-release relay 128 and alternating current relay 125. Relay 128 is made slow-to-release for the purpose of keeping the circuit for relay 125 closed should false ringing current be trans mitted momentarily over lead 134.

The operation of relay 125 was mentioned above and its operating circuit may be traced from ground on theleft front contact of re lay 128,1eft back contact ofrelay129, windingof relay 125, innerle'ftback contact of relay 126, conductor 134, inner front contact of'relay 132, brush 140, terminal 210, com ductor 225, right back contact of relay 209, side-switch wiper 213, brush 221, terminal 231, outer left front contact ofrelay 233, ring of jack 240 and plug 241 to ringing generator 261 through the outer front contact of relay 253. The operation of relay 125 opens the locking circuit of relay 128, thereby opening the above traced circuit for relay 123. It is therefore apparent that the measured interval of ringing current from the intercepting operators cord will prevent the operation of register 106.

,When a manual operator is" requested to obtain a connection with a subscriber in a three-wire oflice, plug 305 of the operators cord circuit 0C (shown on Fig. 3) is inserted in jack 306. Relay 307 operates over a circuit from ground through its winding, conductor 312, sleeve of jack 306 and plug 305,

lamp 304, resistance 300, to battery. At the same time relay 311 is operated over a circuit from-battery through its winding,back contact of relay 315, conductor 323, tip at of jack; 306 and plug305, upper normal contact of key 303, upper winding of repeat coil 350 to ground. Relay 309 also operates over a 307, -inner left fronticontact of relay 3 09 to ground through its winding. Theoperation of relay 309 alsoconnectsl relay 313 to the ring sideof the 'trunltover conductor 322 and operates relay 310 overv a circuit from ground on the middle left front contact of relay 309 to battery through thewinding of relay310. Relay 313 does not operate at this time. To mark the trunk as busy, relay 309upon operating connects the make-busy circuit329 throughthe coil 319 over the right front contact of relay 309 to the sleeve of jack 6. -The operation .of relay 310, (ionnects the windings of relay-315 in series with resistance 321 and coil 320 across conductors 324 and 325 but re1ay315 does not operate at this time. ltsoperation will .be described later. The circuit is now in condition for dialing and the manual operator operates key 303, thereby connecting dial 302 across the tip and ring of the cord. Relay 311 re-' mains operated through contact '326 of'the dial. When the dial is moved ofli normal,

ground islconnected to the ringithroughoif- -normalcontactr327, lower make contact of key' 303, ring of pl ug.305 and jack 306, conductor 322-, outerleft front contact, of relay 309, right backcontact ofirelay 314 tobat tery throughjthewinding: of relay313. The

operation of relay 313 connects conductor 351 to conductor 335 and operates relay 317 over 7 an obvious circuit. Relay 31? operated disconnects conductor 33; from conductor 324 and connects ground from its left front. contact, over the front. contact of relay 311 through the winding ofrelay 316 to battery,

thereby operating relay316. .Rela .316 looks over a circuit from battery throug its winding,,left front contact,-back contact of relay 318to ground on the middleleft front contact of relay. 309. v v J While the dial 302'returns'tonormal, the

'pulsingcontacts 326 open and closetheoperating circuit for. relay 311 a certain number of times I corresponding, to the digit dialed. The operation and releaseof relay 311 intermittently connects ground to conductor .335

for operating the vertical relay, 330 inthe 'first trunk selector FT S' overacircuit from ground, on the left front contact of relay 317, back contactofrelay 311;, outer right front contact of relay 313,. conductor. 335to' battery through the winding of vertical relay mal,the olf-normatcontact.327'isopened .and relay 313, releases openingithe circuit 330. Theoperation will befthe same is described above for the firstitrunk selectors with the exception of the rotary impulse from the trunk OT. When the dial Ireachesnorthrough relay317 Relay 317, however, being slow to release, releases after an interval duringWhich time ground from the right inner back contact ofrelay 313 (which contact is a make-before5breakI spring combination) is connectedto conductor. 33f]; causing relay 331 to operate and cause the trunk" selector to rotate as hereinbefore described.

'Itwill be notedthat thenumb'ering forv this particular circuit is the same on both figures with the exception of the hundreds numeral which corresp ondsto the figure number. The connector C and intercepting operators circuits will function in thesame manner as describedabove until ringing source 261 is applied to the connection.

On acall successfully completed to a subscribers substation, when the subscriber 320, resistance 321 and the right front contactof relay 310 to conductor 324 and battery at relay 202.]..The operation of relay 1315 opens the, circuit forrelay 311"releasing it,

andcloses a circuit for relay314: from ground removes the receiver. from 'the switchhook, I

through the upper winding of repeat coil3'50,

upper normal contact of key 303, tip of plug 305 and jack 306,;condu'ctor 323, fr0n't"contact of relay 315, rightv {front contact of relay 316, -winding of relay 31%1,;conductori3 22,

ring of jack 306 and plug 305, lower normal contact of key .303, winding of relay 308, lower winding of repeat'coil350 to battery.

The. resistanceof'relay 31 1 is such that it al-v lows relay 308. to operate and connect resistance355across thelamp 30a extinguish ingiitf The extinguishing' of lamp 304 indicates to the originating operator 'tha't the connection has been {successfully completed and shemayf operateljme ans to charge the n is 'therefore not dear ut"v tagaaae operator a'signal'on a'call to an intercepting operator. This is effected by means of ringwinding of relay 318,1eft back contact of dug-source 261 over a circu it1-from;ground on the middle leftfront contact of'relay 309,

relays 31a and 313, ,rightffront contact/of .rela-y 310,-conductor 324, right backc'onta'c t ofrelay317, conductor 33 1, inner left front contact'of relay332, brush 34:1, terminal 211, i M

r 20 9, siderswit'chwiper 213, brush 221;, 1 terminal 231, outer left frontcontact of relay .233, ring of'jack 24:0 and plug 24:1, to ringing source'261 through the inner-right front 'conftactofrelay 253; Relay 318 operates'fin this I circuit" and opens :the' locking circuit for, i slow-to'-rel'ease relay 316, "This relayismade 1 3 slow to releasein order that it hold dun conductor 225, right "back 'conta'ct of relay ing short impulses of ringing curreiitjwhich may occur at times other thanrequir'ed. It; :is necessary for'relay' 318 to buzz aycertain I V 1 length oftimein orderl't-o releaserelayf316. V

Ill-he release of relay 316 opens theoperating circuit for relay .314, and the circuit for loperatingsupervisory relay 3 08 is not therei to fore effective and. nosupervisory signal is received b the manual operator.

When t e conversation is completed, the callingsubscriber replaces his receiver on the switchhook. The operator at position 00 takes down the connection, releasing the relays 201 and 202. The connector C is now restored to normal. by means of a circuit from battery, through the winding of release magnet 208, upper contacts of the combination 219, left normal contacts of the spring combination 218 to ground on the terminal 212. Magnet 208 causes the connector to restore to normal and relay 333 operates to brin aboutthe release of the selector in the wellown manner. The withdrawal of the plug 305 from the jack 306 releases relay 307, which in turn, releases relay 309. I The I'eleaseof relay 309 opens the circuit of relay 310.

If the operator at QC desires to break down the connection after it has been extended to the trunk IOT, but'before the operator at IOGhas answered, she may doso by withdrawing the plug 305, whereupon relays 307, 309 and 310 release. The release of relay 311) which is a slow-releasing relay, permits the connection of ground over two circuits, one from battery, through the winding of relay 201, thence over the circuit previously traced to the outer left front contact of relay 332, conductor 335,0uter right back contact of relay 313, conductor 325, left front contact of relay 310, lowerwinding of relay 315,-to'ground at the middle left back contact of relay 309. The othercircuit may be traced frombattery throughthe winding of relay 202, thence as traced to the inner left front contact of relay 332, conductor 334, right back contact of relay 317;conductor 324, right front contact of relay 310, left back contact of relay 307, upper winding of relay 315, to

groundat the middle left back. contact of relay 309. The operation of relays 201 and 202 closes a circuit from battery t rough the .Wiudin of release magnet 208, upper contacts ol 'the spring combination 218, right contacts of thespring combination 219 to and 202 in a mannersimilar to that described;

What is claimed is:

1. In a telephone exchange system comprising automatic switches employed for extendin calls from one subscri er to another and on charging means automatically operable upon completion of such calls, intercepting operator position circuits to which certain current to operate said relay calls are automatically extended, apparatus to disable the operating circuit for said" call charging means, an intercepting operators cord circuit, and means in said cord circuit automatically operable to operate said disablin apparatus.

2. Tn a telephone exchange system comprising automatic switches employed for ex tendin calls from one subscriber to another and ca 1 charging means automatically operoperable upon completion of such calls, in-

tercepting operators position circuits to which certain calls are automatically extended, an alternating current relay effective when operated fora measured length-10f time to disa le the operating circuit ofsaid call charging means, an intercepting operators cord circuitrand meansin said cor circuit toautomatically supply alternating current to operate said relay forsaid measuredlength of time. i

4. In a telephone exchange system comprising automatic switches employed for extending calls-from one subscriber to another and call charging means. automatically operable upon completion of such calls, intercepting operators position circuits to which said calls are automatically extended, an alternating current relay, means under thecontrol of saidrel'ay effective when said relay is operated fora measuredlength of time to disable the operatingcircuit of said call char 'ng means,an interc ting operatorscor circuit, and means m'said cord circuit to automatically supply alternating for-said measured lengthof time.

5. In a telephone exchange system com prising automatic switches em loyed for extendin calls from one subscriberto another and ca l charging means automatically operable upon completion of such calls, intercepting operators position drcuitstowhichcertam calls are automaticall erated for a measured length of timeto disable the operating circuit for said call charging means, anintercepting operators cord circuit,meansin said circuit to automatically supply alternating currentto operate said relay for-said measured len th of time, and means to render said disabfing means inefextended, an alternatingcurrent relay e active whenopfective' if said. alternating current relay is operated for less than sald measured length of time.

6. In a telephone system having aplural-, ity of lines, automatic switches for extending connections from an originating point to a called line, a current responsive device at the originating point,,means controlled by the called party in answering for operating said device, an intercepting operators position I and a cord clrcuit thereat means for causing said switches to extend certain connections to said position, means in the op'erators cord circuit forsending a discriminatory'signal back over the extended connection to theor iginating point, and means operated in re sponse to saidlsignal for disabling the means for operating said current responsive device.

7. In a telephone system, a calling oflice and a called ofiice, trunk lines interconnecting said offices,automati -switches for-eXQ operating said current responsive device, 7 means for dlsabling sald current respons ve J tending connections from the calling oifice device, an intercepting operators position at the called office, means for causing said switches to route certain connectlons to-sald position, a cord circuit at the operators position, and means in said cord circuit for causing the operatlon of said dlsabllng means to prevent the operation of said current responslve ClGVlCGlIl the calhng office.

In Witness whereof; We hereunto subscribe our names, this 27th day of August, A. D.,

'EMIL JACOBSEN. I ARTHUR B.- SPERRY,