US749798A - Central-energy telephone system - Google Patents

Description

No. 749,798. v PATENTED JAN. 19,1904.

K. B. MILLER. CENTRAL ENERGY TELEPHONE SYSTEM.

APPLICATION FILED DEO. 19. 1.900. N0 MODEL.

LT E l L m: onlus paens no. mormurnc.. vAsmuomu. n.-

UNITED STATES Patented January 19, 1904.

PATENT OFFICE.

KEMPSTER B. MILLER, OF CHICAGO, ILLINOIS, ASSIGNOR TO KELLOGG SWITCHBOARD AND SUPPLY COMBANY, OF CHICAGO, ILLINOIS, A

CORPORATION OF ILLINOIS.`

CENTRAL-ENERGY TELEPHONE SYSTEN-I.

SPECIFICATION forming' part of Letters Patent No. 749,798, dated January 19, 1904.

i Application Ied December 19, 1900. Serial No. 40,372. (No model.)

To all whom, t may concern:

Be it known that I, KEMISTER B. MILLER, a citizen ot' the United States, vresiding at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement `in Central-Energy Telephone Systems, of which the followingV is afull, clear,

concise, and eXact description', reference being had to the accompanying drawings, forming a part of this specification. y My invention relates to a central-energy telephone system, my object being to provide an improved form of telephone system wherein the source of current for energizing the talking-circuits and the signaling apparatus a is located at the central station.

. view of a plug-seat switch.

the signaling device inert.

i I have Illustrated my invention In the aci My invention relates more particularly to the signaling apparatus at the central station by means of which the subscriber signals the operator.

I have shown and described one specific embodiment of my invention for the purpose of illi'istrating the generic principle underlying my invention. 'In accordance therewith I provide a relay and a plug-seat switch adapted to conjointly control the signaling device at the central station. I preferably arrange the relay so that the sameis energized when the subscribers are connected for conversation, to thereby render the signaling device inert. In this manner the signaling device may be actuated to convey the signal for disconnection to the operator'by the hanging upofthe subscribers telephone-receivers. The return of the connecting-plug to its seat serves to actuate the plug-seat switch and again render companying drawings, in which- Figure l is a diagram showing two subscribers telephone-lines and the central-station connecting apparatus. Fig. 2 is a detail gram showing the talking-circuit. Fig. 4 is a view of a modified form of the signaling-cirf cuit.

Like characters refer to like parts in the several figures. i

Fig. 3 is a diatact 2, which 'is connected through individual annunciator c' to conductor 3. The springs a2 anda'i carry armatures resting opposite the poles of the relay-magnet and the spring a2 when attracted is adapted to engage contact 4, which is connected withthe line-springs 0l d.

- rI`he spring a3 is adaptedwhen attracted to engage contact 5, which is connected with` the sleeves (Z2 (Z2 of the spring-jacks d el. Moving with the spring (L2, but insulated therefrom, is a'` spring connected to ground through a resistance a5 and adapted when the relay is energized to engage contact 6, which is connected with the test-rings d5. One end of the winding of relay b is connected with conductor 3, andA the other end is connected with the contact-springs Z3 d3, which springs are-mounted to move'with but insulated frorn the line-springs d d', respectively. When the' 'plug is inserted in the spring-jack, the line-spring d is moved by the tip thereof 'to carry thel spring Z3 into engagement with the grounded contact d4.

The subscriber is provided at the substation with the usual microphonef, receiver f', and swItch-hook f2, normally resting against contact 7, which is connected through bell f3 to ground. When the telephone is'removed from the hook, the hook engages contact 8, which is connected with the telephoneftransmitter and receiver. The telephone-line B shown at `the right of the drawings is like the telephoneline A and is provided with the same parts and mechanism, and like parts have been indicated by the same reference characters employed in connection with the line A.

vided with a tip o', connected with strand t', and with a sleeve ai, connected with a strand with the battery fr.

N'. rl`he strands are inductively united through windings of a repeating-coil w, said repeatingcoil comprising windings w 102, connected to the strands t and s, and windings w3 and @04, yconnected between strands t' and s. A battery r is interposed between the windings 'w' and Q02, and a battery/r is interposed between the windings w3 and wi.

A ringing-key g normally rests against contact 17 and is adaptedwhen depressed to engage contact 18, which is connected to ground through generator g. rlhe operators telephone set 2,' is adapted to be bridged between the strands t and s, and a condenser Z is included in circuit therewith to prevent the passage of the battery-current.

, 'lhe conductor 3, extending to a portion of the subscribers lines centering at the eX- ,change, is connected with one ypole of the battery r, while the conductor 3, extending to the remaining' telephone-lines, is connected The opposite poles of thebatteries `r and apregrounded.` The plugs I y) and o normally rest in plug-seats, and plugseat switches are provided adapted to be ac- ,tuated by the insertion of the plugs in their.

respective seats and by the removal of the same therefrom. AThe answering-plug pis adapted when inserted in its seat to separate the spring fm2 from contact 14, and likewise the plug o is adapted to separate the spring o2 from contact 16.

1n circuit with the strand s is a relay-mag` -lposite the relay lf; is a similar spring o, Anormally engaging contact 15. rlhe signaling- ".,lamp viv/.is included in circuit with the battery vf and with thvecontacts of relay la and of the plug-seatswitch actuated by plug p. Likewise the lamp c" is included in circuit with the battery fr and with the contacts of the relay and of the plug-seat switch belonging to plug' o.

. l will now describe the manner in which the y subscribers are connected together for conversation. Supposing subscriber A. desirous of conversing-with subscriber B, he liftshis telephone -receiver .from its hook, thereby closing together limbs a and a at the substation and completing the circuit of .battery fr from ground over conductor 3, individual annunciator c, contact 2, spring a3, limb a,'limb a, spring d?, contact 1,` to ground. The annunciator c is thus actuated, thereby attracting the attention of the operator, whoremoves the answering-plugp from its seat and inserts thesame 1n the spring-Jack belonging rtosubscriber. The insertion of the plug in the spring-jack moves spring Z3 against contact d4, thereby energizing the relay b, the

circuit through said relay beingtraced from ground through battery r, conductor 8, relay b, spring (Z3, contact di, to ground. The relay-magnet 7) upon being energized attracts the armatures carried upon springs a2 and a3 and separates said springs, respectively, frorn contacts 1 and 2'and moves' the same against contacts' 4 and 5. The individual annunciator c is thus removed from circuit, and the terminals of the spring-jacks are connected with the limbs of the telephone-line. rlhe circuit of battery r is now closed through relay 71, over strands s and and limbs va and a', thereby energizing the relay /z and causing the same to attract the. armature thereofl to thus maintain the circuit through lamp m' open. The circuitY through the lamp 711/, which was closed by the removal of the plug p from its seat, is thus opened, and the lamp is thus eX- tinguished. The operator now bridges her telephone set in circuit and having learned the number ofthe called subscriber lifts the calling-plug o and touches the tip r/ thereof to the test-ring to determine whether or not the line of subscriber B called for is busy. 1f

subscriberB is busy, his relay I) will be ener-J gized and spring thereof will rest against contact 6. Upon touching the tip of the calling-plug to the test-ring the operator will he'ar a click in her telephone if the line is busy and the relay energized; otherwise her telephone Will remain silent. rlhis click is caused by the fact that before the tip is touched to the testring the point where the operators telephone set is connected with thestrand t is of the same potential as the battery fr', since the battery is on open circuit. When, however, the tip is touched to the test-ring, the circuit of battery 1" is closed from ground through winding w3, strand t', tip 0, test-ring d'5, contact 6, spring to ground, and due to the fact that the winding w3 is interposed between the pole of the battery and the point where the telephone set is connected with the strand t the potential at this point of connection will be lowered andl a current will thus How throughing currents from ground through generatori g`,strand t', limb a, through subscribers bell vf5, to ground. The' bell of subscriber B is thus actuated,.and when subscriber B removes 'his telephone-receiver from 'the hook, `limbsu a are closed together at the substation. The circuit of battery r is thus closed through rclay over strands z," s and limbs au of substation B. When the operator removes the calling-plug o from its seat, the circuit through IOO IIO

.-eithe telephonefreceiver of either subscriber c Alamp ml. 4 spring m makes contact with contact 13, thus c lamp e is closed and ythe lamp is lighted. When the called subscriber responds and lifts his telephone from the hook, thus closing the circuit oi' battery fr through relay 7c, the spring 117 is separated from contact 15', thus opening the circuit through lamp e .and extinguishing the same. i

lhe talking-circuit is shown in diagram in Fig. 3. r1`he variation 4of resistance caused by the operation of the microphone of subscriber c Avaries the'current delivered by battery fr, thus causing a vibrating l current to traverse the windings 'zu' and 'wzof relay w,thereby inducing corresponding current in the windl ings w3 and uf, which traverse the receiver of subscriber B. Likewise vibratory currents produced by the microphone of subscriber B are transmitted to `the'freceiver of subscriber` A'fVVhen the subscribers have completed theirconversation, they hang up their tele?,kv phone-receivers, and the limbs t a/ are thusA separated at the substation. Thus when sub-` scriber A hangsup his telephone-receiver the limbs (t a are separated at the substation and the circuit of battery 0' through relay is opened, thereby deenergizing said relay and ,permitting spring 'In to engage contact 13 to `thus close circuit through lamp fm.' and light Similarly the hanging up'of the c the same.

V`receiver of subscriber B lights the lampo'.

The lamps thus remain lighted until the plugs have been returned to their respective seats. Thus when plug pis returned to its seat spring m2 is separatedfrom contact 14, thereby opening the .circuit through lamp m and eXtini guishing thesame. Likewise the return of plug o to its seat extinguishes lamp o. The

lamp of the called subscriber is thus lighted as soon as ,connection is made with his line and is extinguished as soon as he removes his telephonefreceiver from the hook,`thereby1 giving the operator the signal that the subscribers are in conversation. The hanging up lights the lamp corresponding' thereto to thereby indicate to the operator that disconj nection is desired. Either subscriber may by vibrating his switch-hook alternately light and extinguish his lamp'to indicate in the usual manner a desire for reconnection.

`In Fig. `4 I have 'illustrated a modification,

oi' the signaling-circuit- The relay Ii instead of being provided with a back contact isprovided with a Jfront contact, the spring m and contact y lbeing connected with opposite sides of the lV hen the relay is energized, the

short-circuitinng thei lampV and extinguishing the same. '1n this modiiication therelay when energized closes together its contacts to eX tinguish the lamp, `while in the form above described therelay when energized separates these contacts to extinguish the lamp. A re-` sistance 71,2 prevents the short-circuiting of the -battery when the lamp is .cut out. rlhis arlrangement does away w'ith the necessity of a back-contact relay.

I disclaim herein thematter claimed inthe p patent to Francis W. Dunbar for telephoneswitcliboard systems, dated ANovember 12,

Having described my invention, what l claim as new, and desire to secure by Letters Patent, is-

1. The combination with a pair of telephone: lines, of a cord-circuitto loop said lines to-4 gether tor conversation and having a connect-V phone-lines, of a cord-circuit to loop any ot' said ,lines together in pairs for conversation and havingr a connecting-plug at each end, a pair of sources of electricity, one for each line of each connectedpair, and Aplaced in circuit therewith by the act of connecting the cordcircuit 'with the lines, a relay associated with each end of the cord-circuit and operatedover the 'metallic telephoneline from the corresponding source of current, a plug-seat switch `for each plug, and a supervisory signal for eacliend of the cord-circuit controlled by the conjoint actionA of the relay and plug-seat switch associated with the corresponding end of thecord-circuit, substantially as described. 3.. The combination with a plurality of telephone-lines, of5a cordcircuit to connect any of said lines together in pairs for conversation and having connecting-plugs, a pair oi sources IOO i iko of electricity one for each line of each connected pair and` placed in circuit therewith by the act of connecting the cordcircuit with the lines, the ends of said cord-circuitbeing inductively united together but conductively disconnected@ relay associated with each end of the cordrcircuit and operated over the telephone-line from the corresponding source oi' current, a plug-seat `switch for each plug of the cord-circuit, and a supervisory signal for each end ofthe cord-circuit, controlled by the conjoint action of the relay and plug-seat switch associated with the corresponding end of the cord-circuit, said signal being actuated whenever the relay is deenergized and the plugis out of the seat and rendered inoperativewh'enei'fer the plug '1s in its seat or there- `lay energized,substantially as described.

, 4. i The combination with a plurality ot' telephone-lines, of acord-circuit to connect any Alao of said lines together in pairs for conversation and having connecting-plugs, means Vto conductively separate but to inductivelyjoin the ends of said cord-circuit, a pair of sourcesof electricity, one bridged across each'end of the cord-circuit and adapted to be included inthe metallic telephone-line when a connection is established, a relay for each end oi' the cordcircuit and in the path of current overthe me-A tallic line, a plug-seatswitch for each plug,.

and a supervisory signal for each plug having its circuit controlled by the `corresponding switch and by said relay and so that the signal is actuated when the plug is out of its aseat 'and the relay denergized and is rendered'inoperative at other times,l substantially as described. ,t Y

5.` The combination with a plurality of'telephone-lines, of a cord-circuit to connect said lines in pairs for conversation, said cord-circuit being provided with connecting-plugs, a repeating-coil interposed between said plugs to inductively unite the same together and to conductively separate them, a separate source of current. associated with` each end of the cord-circuit and adapted to send current over the metallic telephone-lines when a connection is established, a relay for each endl of thecordcircuit. in they ath of current over the metallic telephone-ine, a plug-seat switch for each plug, and a supervisory signal for each plug having .its circuit controlled. by the corre sponding switch and relay, substantially as described. y I* I 6. The combination withza plurality of telephone-lines, of a cord-circuitcto connect said cuit and between the windings of. said repeatc ing-coil, a relay associated with each end of the-cord-circuit and in one strand thereof, said relay being in the path of current over the metallictelephone-line, a plug-seat switch associated `with each end of the cord-circuitifor the connecting-plug, and a supervisory signal for each plug having its local circuit controlled 4, by the corresponding relay and plug seat n switch, substantially as described.

- 7. The combination with a plurality of telephone-lines, of a cord to variously loop said lines together for conversation and having a connecting-plug at each end, said cord-circuit having only twostrands and the ends thereorl being conductively discontinuous but inductivelyunited, a pair of sources of electricity associated with the cords and lines, one source being independently included in the circuit of each line during the connection, a separateV` yand independent relay associated with each end of the cord-circuit and included in the metallic circuit with the corresponding source of current and telephone-line when a connection is established, and a. supervisory signal for each end of' vthe cord-circuit controlled during conversation by said relay, substantially as described.

8. The combination with a plurality of telephone-lines, of a cord-circuit to connect any of said lines together in pairs for conversation and having a connecting-plug for each end, meansto conductively separate but inductively unite the said ends of the cord-circuit, a pair of sources oi' electricity, one bridged across each end of the vcord-circuit and adapted to be included in Vthe metallic circuit with the corresponding telephone-line when a connection is established, a separate and independent relay for each end of the cord-circuit and in the path of current over 4 the said corresponding metallic telephone- ',line, and a supervisory signal associated with each connecting-plug and controlled during conversation by the corresponding relay, substantially as described.

9. The combination with a plurality of telephone-lines, of a cord-circuit toconnect any of said lines together in. pairs for conversation and having a connecting-plug for each end, means to 'conductively separate but inductiv ely unite the said ends of the cord-circuit, a pair of'lsources of electricity, one bridged across each end oi' the cord-circuit and adapted to be included in the metallic circuit With the co1 responding telephone-line when a connection is established, a separate and independent relay for each end of the cord-circuit and in the path of current over the said corresponding metallic telephone-line, a supervisory signal associated with each of the connecting-plugs, a local circuit for each said signal, said circuits being controlled at one point by the corresponding relays and at another point by auxiliary means, substantially as described.

10. The combination with 'a plurality of telephone-lines, of a cord-circuit to connect any of said lines together in pairsv for conversation andhaving a connecting-plug for each end, means to conductively separate but inductively unite the said ends of' the cord-circuit, a pair of sources of electricity one bridged across each end of the cord-'circuit and adapted to be included in the metallic-circuit with the' corresponding telephone-line when a connection Iis established, a separate and independent 'relay for each end ofthe cord-circuit and in the path of current'over the said corresponding metallic telephone-line, a supervisory signal foreach end of the cord-circuit, local circuits for saidsignals, said relays serv- Aing when actuated to open said local circuits at one point to render the said signals inert during conversation, and other means to close -said circuits when the plugs are connected with thelines so that the said lsignals may be operated when the subscribers telephonesr are IOO IOS

not in use, and to open the same when the plugs have been disconnected from the lines so that the said signals are again rendered inert, substantially as described.

ll. rIlhe combination with a plurality of tele-4 phone-lines, of a cord-circuit to connect any of said linestogether in pairs for conversation and having a connecting-plug for each end,

means to conductivelyseparate but inductively unite the said ends of the cord-circuit, a pair of sources oi' electricity, one bridged across each end of the cord-circuit and adapted to be included in the metallic circuit with the corresponding telephone-line when a connection is established, a separate and independent relay for each end of the cord-circuit and in the path of current over the said corresponding metallic telephone-line, a supervisory signal associated with each plug, means controlledn nesses.

'- KEMPSTER B. MILLER.

Witnesses:

W. CLYDE JONES,

M. R. NYMAN.

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