US726964A - Central-energy telephone system. - Google Patents

Description

PATENTED MAY 5,' 1903.

K. B. MILLER. CENTRAL ENERGY TELEPHONE SYSTEM.

APPLIOATION FILED NOV. 26, 190n0.

2 SHEETS-SHEET 1.

I0 MODEL.

0,. wnsnmcrm D c PATENTED MAY 5, 1903.

K. B, MILLER. CENTRAL ENERGY TELEPHONE SYSTEM.

APILIGATION FILED Novi. 26, 190`0.l

2 SHEETS-SHEET 2.

H0 MODEL.

No. 726,964. l

UNITED STA-TitsA Patented May 5, 1903.

PATENT FFICE.

KEMPSTER B. MILLER, OF CHICAGO, ILLINOIS, ASSIGNOR TO KELLOGG SWITCIIBOARD AND SUPPLY COMPANY, OF CHICAGO, ILLINOIS, A

CORPORATION OF ILLINOIS.

CENTRAL-ENERGY TELEPHONE SYSTEM.

SPECIFICATION forming part of Letters Patent No. 726,964, dated May 5, 1903.

,Application led November 26, 1900. Serial No. 37,754. (No model.)

T0 all whom, t Htc/y concer-72,:

Be it known that I, KEMPsTER B. MILLER, a citizen of the United States, residing 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 following is afnll,clear, concise,and exact description,reference being had to the accompanying drawings,forn1ing a part of this specification. Y

My invention relates to a central-energy telephone system, my object being to provide improved means whereby the talking-circuits and the signaling-circuits at the central station may be effectively supplied with energizing-current from a centralized supply. It has been customary heretofore in telephone systems of the general class to which the present invention relates to provide at the central station a common battery which snpplies current for the talking-circuits of the connected subscribers and also for the relays which control the supervisory signals at the central station.

In accordance with the present invention, in the preferred form thereof I employ two batteries or sources of electricity, one adapted to be connected in circuit with one of two connected subscribers lines -say the callingsubscribers line-while the other is adapted to be connected in circuit with the other connected subscribers line--to wit, the calledsubscribers line-the two batteries, so far as the talking-currents are concerned,being thus electrically separate and distinct. The batteries, however, coperate in actuating the relay which controls the supervisory signals. The relay which controls the supervisory signals is so arranged that when the subscribers are in conversation the windings of the relay will be traversed by currents from their respective batteries in such a direct-ion as to neutralize the relay-core, whereby the signals remain quiescent. Should one of the subscribers alone hang up his telephone, the circuit through one ot' the batteries will be opened, thereby permitting the other battery to polarize the relay-core to actuate one of the supervisory signals, depending upon which subscriber thus hangs up his telephone.

Should both subscribers hang up their telephones, a circuit is closed through the windings in such a manner as to actuate both of the supervisory signals. I preferably employ the repeatingcoil interposed between the two connected lines as the relay for operating the 'supervisory signals, as will be here inafter described.

I have illustrated my invention in the accompanying drawings, in which- Figure l is a diagram showing two subscribers telephone-lines and the central-station apparatusequipped in accordance with myinvention. Fig.2isadiagramshowingthe circuits when the subscribers are connected for conversation. Fig. 3 is a view showing diagrammatically the manner in which the windings of the repeating-coil and relay are superimposed. Fig. 4 is a diagram showing the circuit for controlling the supervisory signals to convey the clearing-out signal. Fig. 5 is a diagram showing the manner of connecting the batteries with the plurality of telephone-lines. Fig. 6 is a diagram showing a modification of my invention.

Like characters refer to like parts in the several figures.

As shown in Fig. l, the line of subscriber A extends in two limbs a ct to the central station, where the limbs terminate in the linesprings a2 a3, respectively, of the spring-jack. The spring a2 normally rests against contact c4 and the spring c3 against contact a5, between which contacts the battery b and individual annunciator c are connected. The subscriber is provided at the substation with the usual receiver d and with a microphone d', connected directly in the circuit. The switch-hook d2 normally rests upon back contact d3, which is connected through bell d4 to ground. When the receiver is removed from the hook, the same engages contact d5 to close together the two limbs of the telephoneline. The subscriberB is provided with similar mechanism andis similarly connected with the central station, and I have employed the IOQ Vjack-belegging to subscriber A.

f phone-circuit.

nected by strand s through winding l, carried upon the core f, the opposite end of said winding being connected with battery g and thence through winding 2 to the tipstrand t, which is connected with the tip e. of the plug. Likewise, the callin g-plug h is provided with a tip h and asleeve h2, the former being connected by strand t' through ther ringing-key Z and thence through winding 4, battery g, and winding 3 to sleeve-strand s', which is connected with the sleeve h2. The windings 1 and 2, which are connected with battery g, are wound upon the core in such a direction that the current from the battery g traverses thetwo windings in a direction to add the magnetic etects thereof-that is, in such a direction as to set up lines of force in the same direction in the bent bar f on which they are wound, as is indicated by the arrows adjacent said coils. Likewise, the windings 3 and 4, connected with battery g', are adapted, when traversed by the current from battery g',to add their magnetic effects in polarizing the core f, as shown by the adjacent arrows. Opposite the poles of the corefsprings m o are provided, the spring fm, carrying an armature adapted to rest opposite the polef', while the spring 0 carries an armature adapted to rest opposite the polefz. The armatures are polarized with like polarity-for instance, with positive polarity. The springs m and o are connected with one side of the battery b, while the back contacts m' and o' thereof are connected with the opposite side of the battery, the supervisory signalor lamp rm2 being connected with the contact m and the lamp o2 with contact o'. Each of the batteries g g preferably consists of about ten cells of low internal resistance.

The spring Z of the ringing-key is adapted to vibrate between the contacts Z and Z2, the latter being connected to ground through the calling-generator Z3.

The operators telephone set Zt is connected in the usual manner between the contacts Zo and k2, adapted to be connected with the opposite strands of the cord connectors, to thereby bridge the operators telephone in circuit.

Supposing subscriber A desirous of conversing with the subscriber B, he removes his i telephone-receiver from the hook, thus closing circuit of battery Z) through annunciator c to contact a5, spring a3, limb a', hook d2, contact CZ, limb a, spring a2, contact a4, back to the battery b. The individual annunciator c is thus actuated, thereby attracting the attention of the operator at the central station. The operator thereupon lifts answering-plug e and inserts the same in the spring- The springs a2 and a3 are-lifted from their contacts a4 and a5, respectively, and the individual annunciator c is thus disconnected from the tele- As soon as the plug e is inserted the circuit of batteryg is closed through windings 1l and 2 and through the two limbs of the telephone-line, since the subscribers receiveris removed from the hook, and current is thus caused to traverse windings 1 and 2 in such a direction as to impart to pole f2 a negative polarity, while imparting a positive polarity to pole f. The armature of spring o is thus attracted, thereby closing the circuit of batteryb through spring o, contact o', and lamp o2, thereby lighting the lamp. The operator now connects her telephone set in circuit in the usual manner and receives the number of the called subscriber. Learning that subscriber B is desired, she lifts the 'calling-plug Zz, which is the companion to the the hook', the circuit of battery g' is closed through windings 3 and 4, which tend to polarize the core fand in a direction opposite to that in which the windings 1 and 2 tend to polarize the same, and the core is thus rendered neutral and inert. The armature of spring o is therefore released to open the circuit thrcugh lamp 02,'and the lamp o2 is eX- tinguished to signify to the operator that the called subscriber has answered and that the parties are in conversation.

The circuit during conversation is shown in Fig. 2. l/Vhen subscriber A is talking, his microphone serves to vary the resistance of the circuit of batteryg, while when subscriber B is talking the resistance of the circuit of battery g is varied.

In Fig. 2 the various parts are marked to correspond with similar parts shown in Fig. 1. As shown in Fig. 3, the windings'l and 4 are superimposed on the same leg of the bent bar f, while windings 2 and 3 are superimposed on the other leg. Therefore any fluctuation of an electric current in either of the circuits containing 1 and 2 or 3 and 4 will be reproduced on the other circuit by the wellknown laws of electromagnetic induction. When, however, the resistance of the circuit ot` subscriber A is being varied by the microphone at that station, the windings 1 and 2 in series act together as a primary coil of an induction-coil of which the secondary is formed by windings 3 and 4. When the microphone at station B is in action, windings 3 and 4 serve as the primary coil and 1 and 2 as the secondary.

When the parties have completed their conversation, they hang up their telephonereceivers, thereby actuating the Vsupervisory signals to convey the clearing-out signal to the operator.V If one of the subscribers alone hangs up his telephone,oneof the lamps alone will be lighted, while if both subscribers hang up their telephones both lamps will belighted. Thus, if subscriber A hangs up his telephone, while subscriber B does not, the circuit of IOO IIO

battery g will alone be closed, and the core f will be polarized with a negative polarity at f' and positive polarity at f2, thereby lighting the lamp m2 to signify to the operator that the subscriber A has completed conversation. Likewise, it' subscriber B hangs up his telephone, while subscriber A does not, the battery g will alone be included in circuit, and the windings l and 2 will produce a negative polarity atf2 and a positive polarity at f', thereby lighting lamp o2. lf both subscribers hang up 'their telephones, then circuit will be closed from the ground at substation A, through the bell d, over limb a' and strand t, through winding 2, battery g, conductor 5, battery g', winding 4, strandt', and limb ct' of subscriberB, through his bell to ground. The windings 2 and 4 are thus energized, and as the windings are upon opposite legs of the core f and tend to polarize the core oppositely the result will be that poles f' and f2 will be of negative polarity, while a consequent pole will be formed at the bend of the core. The armatures of levers rm and o will therefore be attracted to close circuit through the'supervisory lamps m2 and 02. The circuit for the clearing-out signal when both subscribers hang up their telephones is shown in Fig. 4.

As shown in Fig. 3, I superimpose the windings mounted on each leg of the relay-core and wind each coil over the entire length of the leg. This construction renders the action as a repeating-coil more efficient and at the same time makes it possible for steady currents in one winding to be completely neutralized by steady currents in the other winding on the same leg of the core. This neutralization of the core of the repeatingcoil is of material advantage in its effect upon the efliciency of the apparatus when acting as a repeating-coil, for iron in a neutral state is more susceptible to slight changes in magnetism caused by varying currents than when the iron is strongly polarized in one direction or the other.

In Fig. 5 I have illustrated the manner in which a plurality of pairs of connected telephone-lines are associated with the pair of batteries. The telephone-lines A and B are connected through the windings l 2 3 4 of the repeating-coil, the battery g being in circuit with the windings 1 and 2, while battery g' is in circuit with windings 3 and 4. Likewise lines C and D are connected through windings l 2fL 3'LL 4'"L of a second repeatingcoil and lines E and F through windings lb 2b 3" 4b of a third repeating-coil. One line of each connected pair is thus connected with battery g, while the other line of each pair is connected with battery g. In practice I preferably connect all ot' the answering-plugs with one of the batteries-say battery g-and all of the calling-plugs with the other battery, gh

In Fig. 6 I have shown a modification ofthe relay in which an armature is provided on the spring p and mounted opposite the bend of the core f. This spring p is connected with one pole of the battery b and is adapted when attracted by the consequent pole developed at the bend of the core to'engage contactspp2,the former being connected through lamp m2 to the opposite pole of the battery, while the latter is connected through lamp 02. The springs m and o are formed integral and pivoted, so that but one can engage its contact m' or o at a time. When circuit is closed through but one of the batteries g or g', one or the other of the lamps m2 o2 will be lighted, as above described. When both subscribers han g u p their telephones to send the clearingout signal, a consequent pole is developed at the bend of the core, and spring@ is attracted, thereby closing circuit through lamps m2 and o2.

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

1. The combination with a plurality of telephone-lines, each having a microphone connected directly'in circuit at the substation, ot means for connecting any two of the lines together in pairs for conversation, a repeatingcoil interposed between the lines of each connected pair, and a pair of common sources of electricity at the central station, one source placed in circuit with each line of each pair and a winding of said repeating-coil by the act of establishing the connection for conversation, substantially as described.

2. The combination with a plurality of telephone-lines, terminating at a central office', of means for connecting the same together in pairs for conversation, and a pair of sources of electricity common to the plurality of lines, one adapted to be included in circuit with each line of a connected pair by the act of establishing the connection, substantially as described.

3. The combination with a plurality of telephone-lines, of means for connecting the same in pairs for conversation, a pair of sources of electricity common to the plurality of lines and connected therewith in the act of establishing connections, one adapted to be ineluded in circuit with the lines of the calling subscribers, and the other in circuit with the line of the called subscribers, substantially as described.

4. The combination with a plurality of telephone-lines, of a plurality of cord connectors for connecting the same in pairs, and a pair of sources of electricity, one member of each cord connector being connected with each et said sources of electricity, whereby said sources are common to the plurality of lines and are connected therewith by the act of establishing the connections, substantially as described.

5. The combination with a plurality of telephone-lines, of a plurality of pairs of connecting-plugs,a repeating-coil interposed between the plugs of each pair, and a pair of sources IIO of electricity, one plug of each pair being connected in circuit with one of said sources and the other plug of each pair in circuit with the other source, substantially as described.

6. The combination with a plurality of telephone-lines, of a plurality of pairs of connecting-plugs,arepeating-coilinterposed between the plugs of each pair, each winding of each repeating-coil being divided into two parts, and a pair of sources of electricity, one interposed between the two parts of each winding connected with the answering-plugs, and the other source interposed between thetwo parts of each winding connected with the callingplugs, substantially as described'.

7. In a telephone-exchange system,the combination with a plurality of telephone-lines, each having a transmitter at the substation connected in circuit with its main line, of a cord-circuit at the central office to inductively unite said lines in pairs for conversation, two sources of current-supply arranged to be connected in circuit with the said main lines by the act of uniting the lines for conversation by means of the said cord-circuit, one source with one line of the connected pair and one source with the other line of the pair, whereby each of the two connected main lines is independently supplied with current from a separate source for conversational purposes, substantially as described.

8. In a telephone-exchange system,the combination with a plurality of telephone-lines, each having a transmitter at the substation connected directly in its main-line circuit, of a suitable calling-signal for each said line at the central ofce and rendered inoperative when a connection for conversation is made with the said line, a cord-circuit at the central office to inductively unite said lines for conversation, two sources of current-supply arranged to be connected in circuit with the said main lines by the act ot' uniting the lines for conversation through the medium of the cord-circuit, one source of current with one line of the connected pair and the other source with the other line of the pair, whereby each of the two connected main lines is independently supplied with current from a separate source for conversational purposes, substantially as described.

9. In atelephone-exchange systexn,the com'- bination with a plurality of metallic-circuit telephone-lines, each having a transmitter at the substation connected in the main circuit of the metallicline, of a cord-circuit at the central ottice to inductively unite said lines in pairs for conversation, two sources of current arranged to be connected in circuitwith the said metallic lines by the act of uniting the lines for conversation through the medium of said cord-circuit, one source of current being connected with one line of the united pair and the other source with the other line of the pair, whereby each of the two connected metallic lines is independently supplied with current for conversational purposes from a separate source of supply, substantially as described.

10. In a telephone-exchange system, thev combination with a plurality of metallic telephone-lines, each having a transmitter connected directlyin the-metallic line at the substation, of a suitable calling-signal for each line at the central office, means lto render the said signal inoperative when a connection for conversation is made with the said line, a cord-circuit at the central office to inductively unite said lines in pairs for conversation, two sources of current-supply at the central office arranged to be connected in circuit with the said metallic lines by the actof uniting them together for conversation through the medium of the cord-circuit, one of said sources of current being connected with one line of the united pair and the other source with the other line ot' the pair, whereby each of the two connected main lines is independently supplied with current for conversational purposes from a separate source, substantially as described.

11. ln a telephone-exchange system, the combination With a plurality of metallic telephone-lines, each having a transmitter at the substation connected directly in circuit with its main line, of a suitable calling-signal for each said line at the central ofce, said signal being rendered inoperative when a connection for conversation is made with the said line, a plurality of cord-circuits at the central ofce toinductivelyunite said linesin pairs for conversation, two sources of current-supply at the central ottico arranged to be connected in circuit with said pairs of main lines by the act of uniting the lines together forconversation through the medium of the cord-ci rcuits, one of said sources being thereby connected with one of the lines of each pair and the other source with the other line of the pair, whereby each of the two connected main lines is independently supplied with current from a separate source for conversational purposes, said two sources of current being com- IOO IIO

mon to the plurality of cord-circuits, substantially as described.

12. In av telephoneexchange system, the combination with a plurality of telephonelines, each having a transmitter at the substation connected directly in its main-line circuit, of a calling-signal for each said line at the central ofce, a central source of current common to the lines and normally connected therewith to control the operation of said signals, said signals being rendered inoperative when a connection for conversation is established with the lines, a plurality of cord-circuits at the central ofiice to inductively unite said lines in pairsfor conversation,two sources of current-supply arranged to be connected in circuit with the pairs of main lines by the act ot connecting the cord-circuits with the lines, one of said sources being connected with one line of each kunited pair and the other source with the other line of the said pair, whereby each of the two lines of the united pairs is independently supplied with current from a separate source for conversational purposes, said two sources of current being common to the said plurality of cordcircuits in the order named, substantially as described.

13. The combination with a pair of telephone-lines, of a separate source of electricity in circuit with each line, a relay having a core and an armature opposite each pole thereof, said armatures being polarized alike, a signaling device controlled by each armature, and windings on said core one in circuit with each source and arranged to neutralize the core when both sources are in circuit, substantially as described.

14. The combination with a pair of telephone-lines, of a separate source of electricity in circuit with each line, a combined relay and repeating-coil having a core and an armature opposite each pole thereof, said armatures being polarized alike, a signaling device controlled by each armature, and windings on said core one in circuit with each source and arranged to neutralize the core when both sources are in circuit, substantially as described.

15. The combination with a pair of telephone-lines, of a separate source of electricity in circuit with each line, a relay having a core and an armature opposite each end thereof, said armatures being polarized alike, a signaling device controlled by each armature, a pair of windings on said core onein circuit with each source a part of each winding being mounted on opposite ends of said core, and said windings being so distributed and arranged on said core as to neutralize the core when both sources are in circuit, substantially as described.

16. The combination with a pair of telephone-lines, each having two limbs, of a separate source of electricity in circuit with each line, a relay having a core and an armature opposite each pole thereof, said armatures being polarized alike, a signaling device controlled by each armature, a pair of windings on said core, one in circuit with each source, lpart of each pair being mounted on opposite ends of said core, said several windings being arranged to neutralize the core when both sources are connected in their individual circuits, and means actuated by the hanging up of both subscribers telephones for closing circuit through said sources in series and through one winding on each end of said core to attract bot-h armatures, substantially as described.

17. The combination with a pair of telephone-lines and a signal, of a pair of sources of electricity adapted to be individually included in the circuits of the telephone-lines for talking purposes and acting conjointly to control said signal,substantially as described.

18. The combination with a pair of telephone-lines joined by a repeating-coil, of a pair of sources of electricity at the central station one in circuit with each line, and a signal controlled by the conjoint action of said sources of electricity, substantially as described.

19. The combination with a pair of tele phone-lines, of a pair of sources of electricity, means for including said sources of electricity, one in circuit with each of said lines, and for including both of said sources of electricity in series in a common circuit, and a signal controlled by said sources of electricity, substantially as described.

20. The combination with a pair of telephone-lines, of a pair of sources of electricity, means for including said sources of electricity, one in circuit with each of said lines, at one time and under certain conditions of use and for including both of said sources of electricity in series in a common circuit at another time and under other circumstances of use, and a signal controlled by said sources of electricity, substantially as described.

21. The combination with a pair of telephone-lines, of a pair of sources of electricity, means for including one of said sources of electricity in each of said lines, and for including both of said sources in series in a circuit including both lines, and a signal controlled by said sources, substantially as described.

22. The combination with a pair of metallic-circuit telephone-lines, of a pair of sources of electricity, means for including one of said sources of electricity in circuit with each of said telephone-lines, and for including both of said sources of electricity in a circuit including in series one limb of each of said lines, and a third conductor, and a signal adapted to be controlled by said sources of electricity, substantially as described.

23. The combination With a pair of telephone-lines united through a repeating-coil, of a pair of sources of electricity, one in circuit with each of said lines, a signaling device comprising a magnet having a Winding in circuit with each of said lines, said Windings being arranged to neutralize each other when both sources of electricity are in closed circuit and to energize said magnet when one of said sources alone is in circuit, substantially as described.

In Witness whereof I have hereunto subscribed my name in the presence of two witnesses.

KEMPSTER B. MILLER. Witnesses:

WILLIAM -W. DEAN, T. W. DUNBAR.

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