US796441A - Telephone system. - Google Patents

Description

fNo. 796,441. PATBNTED AUG.'8, 1905.

K. B. MILLER.

TELEPHONE SYSTEM.

APPLICATION rum) PEB. 4. 1901.

UNITED STATES PATENT OFFICE.

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

CORPORATION OF ILLINOIS.

TELEPHONE SYSTEM.

Specification of Letters Patent.

Patented Aug. 8, 1905.

Application filed February 4., 1901. Serial No. 45,928.

T0 all whom it nfl/ty con/cern.-

Beit 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 Telephone Systems, of which the following is a full, clear, concise, and eX- act description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to a central-energy telephone system, my object being to provide an improved form of signal apparatus at the central station.

In accordance with my invention I provide a repeating-coil through which the telephonelines are adapted to be united for conversation, the charging source of electricity and the windings of the signal-controlling electromagnet being placed in a bridge between the two limbs of the talking-circuit.

The present invention contemplates means for preventing the charging source of electricity from becoming short-circuited through the windings of the repeating-coil, and to this end I preferably interpose a condenser in the bridge containing the windings of the repeating-coil, although the present invention contemplates any means for opening the circuit through the windings of the repeating-coil to prevent the passage therethrough of the current from the charging source.

Ihave illustrated my invention in the accompanying drawings, in which- Figure l is a diagram illustrating two telephone-lines and the central-station apparatus for uniting the same for conversation. Fig. 2 is a diagram showing the talking-circuits of two connected subscribers. Fig. 3 is a view of a modification in which the condenser is placed upon one side of the windings of the repeating-coil. Fig. L is amodication in which a single condenser is employed for both windings of the repeating-coil.

Like characters refer to like parts in the several figures.

The telephone-line A extends in two limbs a a' at the central station, where said limbs terminate, respectively, in the springs a2 a3, the spring a2 normal'ly resting against back contact 1, which is connected to ground, the spring a3 normally resting against back contactZ, which is connected, through individual annunciator c, to conductor 3. The springs a2 a3 carry armatures resting opposite the poles of a relay-magnet b, and the spring a2 when attracted is adapted to engage front contact 4, which is connected with the linesprings d d of the spring-jacks or switchsockets d d. The spring a3 is adapted when attracted to engage contact 5, which is connected with the sleeves Z2 d2 of the springjacks. Moving with spring a3, but insulated therefrom, is a spring a, connected to ground through resistance a5 and adapted when the relay is energized to engage contact 6, which is connected with the test-rings (Z5 d5. One end of the winding of relay b is connected with conductor 3 and the other end is connected with the contact-springs Z3 da, which springs are mounted to move with but insulated from the line-springs d cZ, respecthereof to carry the spring dsinto engage-v ment with the grounded contact d4.

The subscriber is provided at the 'substation' with the usual microphone f, receiver f and switch-hook f2, normally resting out of engagement with contact 8. The bell f3 and a condenser Z3 are connected between the two limbs a a. When the telephone is removed from the hook, the hook engages contact 8, which is connected with the telephone transmitter and receiver.

The telephone-line B shown at the right of the drawings is like the telephone-line 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.

T he answering-plu-g p is provided with a tip p and a sleeve p2, the former being connected with the'strand t and the latter with a strand s. The calling-plug 0 is provided with a tip 0 and a sleeve 02, the former being connected with a strand t and the latter with a strand s. The strands s and t s are united through a repeating-coil w, having windings w and yw2 connected between the strands t and e and windings w3 and w* connected between the windings and s. f In circuit with windings w and Q02 is a condenser Z, and in circuit with windings w3 w4t is a condenser Z. Be-

tween the strands tand s the windings It and if of a relay 7L are provided, a battery .r being interposed between said windings. Likewise between the strands t' and s the windings i' and 702 of relay 7c are connected, the battery r being interposed between said windings. The windings of the relays are in such a direction that the same assist each other in magnetizing the core. The conductors 3, eX- tending to the telephone-lines, are connected some with the battery r and some withbattery r', and the opposite poles of said batteries are grounded. Opposite the pole of relay ta spring m is provided carrying an armature and 'adapted when the relay is denergized to engage. contact 13. Contact 13 is connected, through the lamp m', with one pole of the battery r and the spring m is connected with tlie"'opposite pole of said battery. Likewise the spring e of relay 7f3 is connected with onepole of battery r and the contact 15 is connected, through lamp c, to the opposite pole of said battery. rlhe contacts m2 and 14: of a plug-seat switch-controlled by plugp are interposed'in the circuit of the lamp m. Likewise the contacts c2 and 16 of a plug-seat switch-controlled by plug 0 are interposed in the .circuit of the lamp e.

In the strands t and s the levers g g of the ringing-key are provided, said levers normally resting against contacts 17 17 and adapted when depressed to engage contacts 18 18, between which the generator g is connected. The operators telephone set z' is adapted to be connected between the strands t and s', anda condenser 12 is interposed in the circuit of the telephone set.

Assuming now that subscriber A is desirous of conversing with subscriber B, he lifts his receiver from the telephone-hook, thereby closing together limbs rt a' at the substation. The circuitof battery r is thus closed over conductor 3, annunciator c, contact 2, spring a, limbs a, a spring c2, contact 1 to the opposite pole of battery r. The individual annunciator c is thus actuated to convey to the operator. the signal for connection, and the operator thereupon lifts the answering-plug p and inserts the same in the spring-jack belonging to subscriber A. The insertion of the plug moves spring Z3 against contact cli, thereby energizing the relay the circuit through said relay being traced from battery r, through conductor 3, relay I), spring d3, contact d* to ground and back to the battery. The relay being thus energized attracts the armatures and moves springs a2 o3 out of engagement, respectively, with contacts 1 and 2, thus disconnecting the annunciator from circuit, and moves said springs into engagement, respectively, with contacts 4 and 5, thus connecting the terminals of the spring-jacks with the limbs of the telephone-line. The insertion of the answering-plug also connects battery fr in circuit through the windings it h2 of relay t and through the strands t and s of the cord-circuit and the limbs a rt of the line. The removal of the answering-plug from its seat closes the circuit through lamp m', thereby lighting the same. The insertion of the plug in the spring-jack closes circuit through the two windings of the relay, thereby energizing the same and opening the lamp-circuit at the contacts m and 13. The operator then connects her telephone set e' infcircuit in the usual manner and receives the number of the called subscriber. Learning that connection is desired with subscriber B, she lifts the answering-plug 0 and touches the tip 0 thereof to the test-ring (Z5, belonging to the springjack of subscriber B. 1f subscriber B is busy, his relay will be` energized and test-ring Z5 will be connected to ground through contact 6 and spring rf. If the line be thus busy, the operator upon touching the tip of plug 0 to the test-ring will hear a click in her telephonereceiver; but, on the other hand, if the line be idle she will hear no click and will know that the line is not busy. The click in the vtelephone is due to the fact that by touching the tip of the plug to the line-contact the potential at the point t2 of strand is lowered. thereby permitting a current to flow through the operators receiver. When the tip 0 is not in contact with the test-ring, the battery r' is on open circuit and the point t2 is therefore of the same potential as the pole of the battery. When, however, the tip of the plug is touched to the test-ring, the circuit of battery r is closed from ground through the winding In', strand t', tip 0', testring d5, contacts 6 and to ground. The resistance thus interposed between the pole of thc battery and the point t2 by the winding c lowers the potential of the point t2 on closed circuit,

and this change of potential of the point t2, with which the operators telephone set is connected, causes a momentary current to flow through the receiver, thereby causing a click therein.

Assuming that the operator finds the line of the called subscriber idle, she inserts the plug 0 in the spring-jack thereof and then depresses the ringing-key g', thereby sending current from generator g over strands t s and limbs a a' through the bell at the substation. Wvhen the subscriber responds, he lifts the receiver from the hook, thus closing together the limbs a a at the substation. The circuit of battery r is thus closed through windings c L2, strands t s', and limbs a a. When the calling-plug0is removed from its seat,the circuit through lamp fu is closed and the lamp is lighted. When the called subscriber removes his'telephone from the hook, current traverses the windings of the relay belonging to the called subscriber and the circuit through the lamp is thus opened at the contacts/u and 15. rlhe circuits during conversation are shown in Fig. 2. When the subscriber A is talking and the microphone is actuated, variation of the resistance thereiny causes a corresponding variation of the difference of potential between the points m and w, and this variation of difference of potential causes a correspondingly-varying current to traverse the windings w and wz, thereby inducing' corresponding currents in windings 'w3 and 104, which pass through the receiver of subscriber B. Likewise when subscriber B is talking the diiference of potential between the points 1/ and y is varied and correspondingly-varying currents will be ycaused to pass through the receiver of subscriber B.

/Vhen the subscribers have completed their conversation and desire disconnection, they hang up their telephone-receivers, thereby opening the circuit of the batteries through the relays. The relay-contacts are thus closed together to permit the lighting of the lamp. Thus when subscriber A hangs up histelephone-receiver the circuit oi' battery r through the windings of relay t is opened at the substation and the contacts m and 13 are permitted to close together, thereby closing circuit through lamp m. In the same manner the subscriber Bin hanging up his telephone opens the circuit through relay r, thereby lighting the lamp c. `When the pIugs are returned to their seats, the lamp-circuits are opened at the contacts of the plug-seat switches. If one of the subscribers should desire an immediate reconnection with another subscriber, he may by vibrating his switch-hook in the usual -manner cause the lamp to be alternately lighted and extinguished to thus convey the signal to the operator for reconnection.

I disclaim herein. the matter claimed in the patent to Francis W. Dunbar for telephoneswitchboard systems, No. 686,272, dated August 12, 1901.

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

1. The combination with a pair of telephone-lines, of a repeating-coilthrou gh which the same are adapted to be united for conversation, a signal -controlling electromagnet bridged between the two limbs of the talking-circuit of each of said lines, a source of electricity adapted to be connected in circuit with said electromagnet, and means Jfor preventing the current therefrom from passing through the winding of the repeating-coil associated therewith, substantially as described.

2. The combination with a pair of telephone-lines, of a repeating-coil through which the same are adapted to be united for conversation, a source of electricity and an impedance element bridged between the two limbs of the talking-circuit ot' one of said lines, like parts associated with the other line, and means for preventing the current from said source or sources from passing through the winding' of the repeating-coil associated therewith, sub stantially as described. i

4. rI`he combination with a pair of telephone-lines of a repeating-coil through which the same are adapted to be united for conversation, a signal-controlling electromagnet and a charging source of electricity bridgedv between the two limbs of the talking-circuit of each of said lines, a switch at each substation 'for controlling the passage of current through the signal-controlling electromagnet connected therewith,'and Va condenser interposed in the circuit of each of the windings of said repeating-coil to prevent the passage of the current from said source through said windings, substantially as described. A

5. The combination with a pair of telephone-lines, ofa repeating-coil through which the same are adapted to be united for conversation, a signal-'controlling electromagnet and a source of electricity bridged between the two limbs of the talking-circuit of both of said lines, and means for preventing the winding of the repeating-coil from short-circuiting said source of electricity, substantially as described.

6. The combination with a pair of telephone-lines, oi' a repeating-coil to connect said lines for conversation, a pair of circuit-controlling electromagnets, one connected in parallel with each winding of said repeating-coil, means for sending charging-currents through said electromagnets, a switch at each substation for controlling the circuit through the electromagnet corresponding to said line, supervisory signals controlled by the electromagnets and means for renderingV the windings ot' said repeating-coil opaque to the passage of the charging-currents, substantially as described. v

7. The combination with a pair ot' telephone-lines, of a repeating-coil to connect said lines for conversation, a pair of signal-controlling electromagnets bridged across the circuit one on` either side of the repeatingcoil, means for sending chargingcurrent through said electromagnets, a switch at each substation controlling' the circuit through the electromagnet corresponding' to that line, a supervisory signal controlled by each magnet and a condenser in circuit with each repeating-coil winding to render the same opaque to the passage of charging-currents,substantially as described.

8. The combination with a cord connector -terminating in connecting-plugs, of a repeating-coil interposed between said plugs, a pair -of signal-controlling electromagnets, one in parallel with each winding of said repeatingcoil, means for sending charglng-currents through the windings of said electromagnets,

- condensers in the path of current through said repeating-coil windings to render the same opaque to the passage of said charging-currents, a plug-seat switch for each of said plugs, and a pair of supervisory signals for the cord connector, one controlled by one of Vsaid electromagnets and corresponding plugseat switch, and the other controlled by the Aother electromagnet and the corresponding plug-seat switch, substantially as described.

9. Thecombination withapairof telephonelines, of a cord-circuit to connect said lines for conversation, a repeating-coil in the cordcircuit to inductively unite its two ends, a pair of signal-controlling electromagnets, one connected in parallel with each winding of said repeating-coil, means for sending a continuous current through said electromagnets,

a switch at each substation for controlling the circuit through the corresponding electromagnet, supervisory signals controlled by said electromagnets, and means Jfor rendering the windings of' said repeating-coil opaque to the passage of charging-currents, substantially as described.

l0.- The combination with a pair of telephone-lines, of a cord-circuit to connect said lines for conversation, a repeating-coil in the cord-circuit to inductively unite its two ends,

a pair of signal-controlling electromagnets, one connected in parallel with each winding of said repeating-coil, means for sending a continuous current through said electromagnets, a switch at each substation for controlling the circuitthrough the corresponding electromagnet, and a condenser in circuit with each winding of said repeating-coil to render the same opaque to the charging-currents, substantially as described.

11. rlhe combination with a pair of telephone-lines, ot' a cord-circuit to connect said substantially as described.

12. The combination with a pair of telephone-lines, of a cord-circuit to connect said lines for conversation, a repeating-coil inductively connecting the two ends of the cordcircuit, a pair of signal-controlling electromagnets connected with the cord-circuit, one in paralled with each winding of said repeating-coil, a separate source of current for sending current through each said electromagnet, a switch at each substation forcontrolling the circuit through the electromagnet and source corresponding to said line, and a condenser for rendering the windings of said repeatingcoil opaque to the passage of charging-currents, substantially as described.

13. The combination with two telephonelines, of a repeating-coil to unite said lines for conversation, a condenser in the circuit of each winding of said repeating-coil, and a charging source of electricity and an impedance element bridged between the limbs of each of the connected telephone-lines, substantially as described.

lli. rlhe combination with two telephonelines, of a repeating-coil to unite said lines for conversation, and a charging source of electricity and a signal-controlling .electromagnet bridged between the limbs of each ofthe connected telephone-lines, said repeating-coil windings being opaque to current from said source, substantially as described.

l5. The combination with a pair of telephone-lines, of a cord-circuit terminating in connecting-plugs to connect said lines for conversation, a repeating-coil in the cord-circuit to inductively unite its two ends, a pair of signal-controlling electromagnets one connected in parallel with each winding of said repeating-coil, means for sending a continuous current through said electromagnets, a switch at each substation for controlling the circuit through the corresponding electromagnet, means to render the windings of said repeating-coil opaque to the passage of charging-current, a plug-seat switch for each of the plugs, and a pair of supervisory signals for the cord-circuit, one signal controlled by one of the electromagnets and corresponding plug-seat switch and the other signal controlled by the other electromagnet and the corresponding plug-seat switch, substantially as described.

16. The combination with a pair of telephone-lines, of a cord-circuit to connect said lines for conversation, a connecting-plug for each end of the cord-circuit, a repeating-coil inductively connecting the two ends of the cord-circuit, a pair of signal-controlling electromagnets connected with the cord-circuit one in parallel with each winding of said repeating-coil, a separate source ot' current Jfor sending current through each of said electromagnets, a switch at each substation for controlling the circuit through the electromagnets and source corresponding to said line, means for rendering the windings of said repeating-coil opaque to the passage of charging-current, a plug-seat switch for each of the plugs, and a supervisory signal for each end of the cord-circuit controlled by the corresponding plug-seat switch and electromagnet, substantially as described.

17. The combination with a pair of telephone-lines, of a cord-circuit terminating in connecting-plugs to connect said lines for conversation` a repeating-coil in the cord-circuit to inductively unite its two ends, a pair of signal-controlling electromagnets one connected in parallel with each winding of said repeating-coil, means for sending a continuous current through said electromagnets, a switch at each substation for controlling the circuit through the corresponding electromagnet, means to render the windings of said repeating-coil opaque to the passage of charging-current, a pair of supervisory signals for the cord-circuit operated over local circuits controlled at one point by the said electromagnets so as to render the said signals inert when the magnets are energized, and other means to complete said local circuit at another point when connections are established with the lines for conversation and to open' them w hen the connecting-plu gs are not in use, substantially as described.

18. The combination with a pair of telephone-lines, of a cord-circuit to connect said lines for conversation, a repeating-coilin the cord-circuit to inductively unite its two ends, a pair of signal-controlling electromagnets, one connected in parallel with each winding of said repeating-coil, means for sending a continuous current through said electromagnets, a switch at each substation for controlling the circuit through the corresponding electromagnet, a plug-seat switch for each end of the cord-circuit, and a signal for each end of the cord-circuit controlled by the associated magnets and plug-seat switches,substantially as described.

19. The combination with a pair of telephone-lines, of a cord-circuit to connect said lines for conversation, a repeating-coil inductively connecting the two ends of the cord-circuit, a pair oi' signal-controlling electromagnets connected with the cord-circuit, one in parallel with each winding of said repeatingcoil, a separate source of current for sending current through each said electroinagnet, and a switch at each substation for controlling the circuit through the electromagn'et and source corresponding to said line, substantially as described.

20. The combination with a pair of telephone-lines, of a cord-circuit to connect said lines for conversation, a repeating-coil inductively connecting' the two ends of the cord-circuit, a pair of signal-controlling electromagnets connected with the cord-circuit, one in parallel with each winding o't' said repeatingcoil, a separate source of current for-sending current through each said electromagnet, and a switch at each substation for controlling the circuit through the electromagnet and source corresponding to said line, substantially as described.

21. The combination with two telephonelines,of acord-circuit to unite said lines for conversation, the ends of said cord-circuit being separated by an inductive device, and a separate charging source of electricity and an impedance element bridged between the strands of each end of a cord-circuit whereby current is independently supplied to each line for talking. substantially as described.

22. The combination with two telephonelines, of a cord-circuit to connect said lines together for conversation, a repeating-coil inductively joining the two ends of the cord-circuit, and a separate charging source of electricity and an impedance element bridged between the limbs of each end of the cord-circuit, substantially as described.

23. The combination with two telephonelines, of a repeating-coil to unite said lines for conversation, a charging source of electricity and asignal-controlling electromagnet bridged between the limbs of each of` the connected telephone-lines, a plug-seat switch for each end of the cord-circuit, and supervisory signals controlled by said switches and electromagnets, substantially as described.

24. The combination with two telephonelines, of an inductive device to unite said lines for conversation, a charging source of electricity and a signal-controlling electromagnet bridged between the limbs of each of the connected telephone-lines, a plug-seat switch for each connecting-plug, and a signal associated with each line during conversation and controlled by the joint action of said plug-seat switch `and said signal-controlling electromagnet, substantially as described.

25. The combination with a pair of telephone-lines, of a cord-circuit to connect said lines for conversation, a repeating-coil to inductively unite the two ends of the cord-circuit, apair of signal-controlling electromagnets bridged across the cord-circuit one on either side of the repeating-coil, means for sending charging-current through said electromagnets, and a switch at each. substation controlling `the circuit through the electromagnet corresponding to that line, substantially as described.

26. The combination with a cord connector terminating in connecting-plugs, of a repeating-coil interposed between said plugs, a pair of signal-controlling electromagnets` one in parallel with each winding of said repeatingcoil, means for sending charging-currents through the windings of said electromagnets during conversation, a plug-seat switch for each of said plugs, and a pair of signaling devices one controlled by one of said electromagnets and corresponding plug-seat switch and the othercontrolled by the other electromagnet and the corresponding plug-seat switch, said seats being arranged when the plugs are placed therein to prevent the display of said signals and at other times to permit the display thereof, substantially as described.

27. The combination with the telephoneylines of a telephone-exchange, of a cord-circuit to unite said lines for conversation, a repeating-coil interposed in the cord-circuit to conductively separate and inductively unite the two ends of the cord-circuit, a charging source of electricity and an impedance element included in a bridge separate from the repeating-coil and between the limbs of each end of the cord-circuit, substantially as described.

28. The combination with a cord'connector terminating in connecting-plugs, ol" a repeating-coil interposed between said plugs, a pair of signal-controlling electromagnets, one in parallel with each winding of said repeatingcoil, means for sending charging-currents through the windings of said electromagnets during conversation, a plug-seat switch for each of said plugs, and a pair of supervisory signals for the cord connector, one signal controlled by one of said electromagnets and corresponding plug-seat switch` and the other signal controlled by the other electromagnet and the corresponding plug-seat switch, said plug-seat switches being arranged when the plugs are placed therein to prevent the display of the signals, substantially as described.

29. rl`he combination with a pair of telephone-lines, of a cord-circuit to unite said lines for conversation, the ends of said cordcircuit being inductively united, a source of current and an electromagnet bridged across each end of the cord-'circuit independent of the inductive device whereby current is supplied t'rom the central oiiice to the substationlines for conversation, and supervisory signals controlled by the said magnets during conversation, substantially as described.

30. The combination with a pair of telephone-lines, of a cord-circuit to unite said lines for conversation, the ends of said circuit being inductively united, an electromagnet connected across each end of the cord-circuit and having divided windings, a source of current interposed between the windings of each magnet to furnish current over the corresponding telephoneline for conversational purposes, and supervisory signals for the cord-circuit controlled by said magnets during conversation, substantially as described.

31. The combination with a pair of telephone-lines, oi a cord-circuit to unite said lines for conversation, the ends of the cordcircuit being inductively united, a separate source of current and an electromagnet bridged across each end of the cord-circuit wherebiT current is supplied from central oi'- iice to each of the substations of the lines for talking, a supervisory signal for each end of the cord-circuit controlled by the corresponding electromagnet to render the same inoperati ve during conversation, and operative during a connection and when the subscribers telephone is o' its hook, substantially as described.

32. The combination with a pair of telephone-lines, of a cord-circuit to unite said lines for conversation, the ends of the cordcircuit being inductively united, a source ot' current and an electromagnet bridged across each end of the cord-circuit whereby current is supplied Jfrom the central office to the substation of the lines for talking, a supervisory signal for each end of the cord-circuit, the circuit of said signals being provided with current by auxiliary means when connection is established and the subscribers telephones are not in use and deprived of operating-current during conversation by the said magnets, substantially as described. l

A33. The combination with a pair of telephone-lines, of a cord-circuit to unite said lines for conversation, the ends of the cordcircuit being inductively united, a source of current and an electromagnet bridged across each end of the cord-circuit whereby current is supplied from the central ofiice to the substation of the lines talking, a supervisory signal for each end of the cord-circuit, the circuits of said signals being controlled at one point by the said magnets and at another point by auxiliary means, substantially as described.

34. The combination with a pair of telephone-lines, of a cord-circuit to unite said lines for conversation, the ends ot' the cordcircuit being inductively united, a source of current and an electromagnet bridged across each end of the cord-circuit whereby current is suppliedvfrom the central oice to the substation of the lines for talking, as'upervisory signal for each end oi' the cord-circuit, each said signal having an independent operatingcircuit controlled at one point by the corresponding relay and at another point by auxiliary means so that the said circuits are completed during connections and. opened under normal conditions, substantially as described.

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

KEMPSTER B. MILLER. Witnesses:

M. R. RooKFoRD, M. R. NYMAN.

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