US1090821A - Telephone system. - Google Patents

Description

F. R. PARKER.

TELEPHONE SYSTEM.

APPLICATION FILED JUNE 20, 1904.

Patented Mar. 17, 1914.

INVy; I Q

wnnssszs: I

o I v COLUMB!A PLANOORAPH can WASHINGTON, D. c.

FREDERICK R. PARKER, OF CHICAGO, ILLINOIS.

TELEPHONE SYSTEM.

ncaaser.

Specification of Letters Patent.

Patented Mar. f7, 1914..

Application filed time 20, 1904. Serial no. 213,284.

To all whom, it may concern Be it known that I, Fnnonnron R. PARKER, a citizen of the United States of America, residing at Chicago, in the county of Cook and State of Illinois, have invented a new or annunciator; to provide improved means for disconnecting the subscribers indicator or annunc1ator and the central statlon signahng apparatus and source of electrical supply from the line when the latter is in use either for conversation or during the operation of calling a subscriberjto provide improved means for operating and con trolling the subscribers disconnect or supervisory indicator or annunciator; to provide an improved arrangement of the line relays in the system; to provide an improved arrangement of the supervisory relays in the system; and to provide improved means for allowing the subscribers to carry on secret conversation by preventing the operator from listeningin on the lines during such conversation.

Other objects will be apparent from the following specification.

In my present invention I have shown a talking telephoneline extending direct from the subscribers station, or stations, to the connection terminals or spring acks of the central station switchboard, and including the windings, or winding, of a linecut-ofi relay therein. Then I have shown a signaling circuit extending from the talking telephone line, between the line cut-off relay and the subscribers station, to signaling apparatus and a central source of electric current. Then the cut-ofi relay is energized, it disconnects the said signaling circuit from the talking telephone line. The cut-off relay is adapted to be operated by any form of electric current, such as a direct, alternating, intermittent, interrupted, or pulsating current. V

It has been the usual practice heretofore, to provide a relay included in a local circuit,

for cutting the central source of current and signaling apparatus from the talking telephone line, but it is an object of the present invention to utilize the talking circuit itself for actuating the cut-off relay.

In the subscribers telephone instrument I employ any suitable circuit arrangement for opening and closing the line circuit or for varying the current over the line. In the plug-cord connecting circuit I employ suitable relays for operating the supervisory or disconnect signals. I have preferably shown the talking battery to be a part of the signaling-in battery, but it is to be understood that the talking source of electric current may be separate from the signaling source of current, if desired. I prevent the operator from listening-in on the lines during conversation between the subscribers, by adapting her listening key to cut the sub scribers lines apart, when depressed.

I have also shown several modifications of my present invention, as will be hereinafter described.

I will now more particularly describe my invention by reference to the drawings, in which Figure 1 is a diagram showing two subscribers lines and the central station signaling and connecting apparatus; Fig. 2 shows the line cutoff relay included in one side only, of the line; Fig. 3 shows separate cut-off relays in the respective limbs of a metallic line, and groundedreturn ringing circuits for party-line ringing; and Fig. 4 shows two individual supervisory relays connected to one side of the plug-cord talking circuit, and one supervisory relay for both supervisory signals connected to the other side of the said plug-cord circuit.

Like characters refer to like parts in the several figures.

The line of subscriber A extends in two limbs K and I from a sub-station to the central station where the said limbs pass through the respective windings Q and P of relay 1 and terminate in the respective connect-ion terminals U and V (or U and V,) of the several spring jacks 2 2 of a multiple switchboard. The thimble IV of one of the jacks 2 is normally insulated from the connection terminals U and V, and is used simply as a guide for the connecting plug. This jack is preferably used for the answering jack. This insulated thimble W 110 is described and claimed in the co-pending application of Parker and Corwin, Serial No. 571,846, filed July 13, 1910, on telephone system. Spring members 0 and L of relay 1 are permanently connected to the limbs K and I, respectively, of the line, and normally engage the respective contacts I and M. Contact N is connected to one pole E preferably the positive, of battery 5, through conductor 0,, and contact M is connected to one pole 1),, preferably the negative, of

"battery at, through lamp 13,. Batteries 4 and 5 are connected in series, and it is immaterial which is the positive or negative end pole of battery 4 5. hen armature T of relay 1 is attracted to the cores S and R, sprin 's O and L are disengaged from con tacts N and M, respectively. In case of a grounded-return or common-return line, the ground or common conductor constitutes one limb of the telephone line.

At the subscribers station I have shown one of a number of circuit arrangements in which the operation of the switch-hook G connects either the receiver C and transmitter J, or the ringer E and condenser D, for use over the line, depending on whether the switch-hook is raised or lowered. The operation of this instrument circuit is well understood and need not be described here.

F or the line of subscriber B, I have shown modified forms of some of the apparatus used in connection with. line A. The other parts of line B are similar to corresponding parts of line A and are denoted by like characters, respectively.

The line of subscriber B extends in two limbs K and I from the sub-station to the central station where the said limbs pass through the respective windings Q, and P, of the double-wound relay 3 and terminate in the respective connection terminals U and V or U and V,) of the several spring jacks 2 2 of the switchboard. Contacts N, and M, are permanently connected to the limbs K and I, respectively, of the line, and normally engage the respective spring members O, and L2 of relay 3. Spring member 0, is connected to one pole E of battery 5, through conductor 0,, and spring member L, is connected to pole D of battery 4t, through the winding of relay 6 and conductor 1),. Relay 6 controls the circuit of battery 4 through lamp B as shown. When armature T, of relay 3 is attracted to core 3,, springs 0, and L, are disengaged from contacts N, and M,, respectively.

In the plug-cord connecting circuit, the main conductors of the connecting plugs 10 and 11 are connected together through the respective condensers I-L and I listen-.

ing key 12, and ringing key 13. Tip strand 0, of answering plug 10 is connected to pole E of battery 5, through impedance coil M,.

Tip strand F, of calling plug 11 is normally connected topole E, "of battery 5,"through spring M,, contact spring L contact J conductor N and impedance coil L,. Sleeve strand D, of answering plug 10 is connected to the middle pole of batteryt 5, through winding K, of relay 7, and conductor Y,. Sleeve strand G, of calling plug 11 is normally connected to the middle pole of battery t 5, through spring T contact Q conductor Z, winding X, of relay 8, and conductor Y,

Supervisory relays 7 and 8 are each provided with spring members F, and E, which are normally disengaged from each, other but adapted to be brought into contact with each other. When core A, of relay 7 is energized, armature R, is attracted thereto and thereby engages contact U, which closes ing I magnetizes the armature J, and produces a north pole N and a south pole S therein adjacent to one end Z, of core A, It will be noticed that whenever the current of battery 4 is closed through winding 1,, the north pole of armature J will always be at the same end thereof, and the south pole will always be at the other end thereof. When an energizing current traverseswinding K, of relay 7 in one direction, a north pole will be produced in A, at Z, which will attract the south pole of J and repel the north pole thereof. When, however, an energizing current traverses winding K, in the opposite direction, a south pole will be produced in A, at Z, which will attract the north pole of J, and repel the south pole thereof. This latter action "causes armature J, to close the contact between spring F, and member E, which closes the circuit of battery 4: through conductors Y, and 11,, supervisory signal spring F,, contact 15,, and conductor G,, and causes WV, to display a signal. When the connecting plug 10 is inserted into a spring jack of a line, and the circuit of the line is open, the current from battery i will traverse the winding K in one direction, through conductor 'Y,, winding K,, sleeve strand 1),, ack spring V or V,,' line conductor X, winding P of relay 1, spring L, contact M, lamp 3,, and conductor D and thereby cause core A, to operate. armature J, so as to close the contact between spring F, and member E, If the circuit of the line is closed while such connection is made therewith, the current from battery 5 will traverse the winding K, in the opposite direction, through impedance coil M,, tip strand C1,, jack spring U, line conductor Y, winding Q of relay 1, line conductor K, substation A, line conductor I, winding P of relay 1, line conductor X, jack spring V or V,, sleeve strand 1),, winding K and conductor Y,, and thereby cause core A to act on armature J so as to break the contact F E or keep such contact from closing. In this manner the supervisory relay 7 operates and controls the supervisory signal W}. The operation of relay 8 is similar to that just described for relay 7, but the poles N and S are shown reversed.

The operators receiver Gr and one winding of repeating-coil D are bridged from contact K, to contact 55, of listening-key 12. Condenser C the other winding of repeating-coil D and the operators transmitter F are connected in a loop as shown and to contact E The battery current for transmitter F is supplied from battery 5 through impedance coil 13,. Impedance coil A, is preferably connected to the receiver G, as shown, to provide means for making a busy-test. lVhen listening-key 12 is depressed, springs L and R are disengaged from contacts J, and P respectively, and engaged with contacts K and S respectively, and spring E, is engaged with contact P Ringing generator 9, is adapted to give an alternating, pulsating, intermittent, or interrupted current, as required, and is preferably bridged from contact N, to contact U,, of ringing key 18, as shown. When the ringing key 13 is depressed, springs and T are disengaged from contacts 0 and Q respectively, and engaged with cont-acts N and U respectively.

The operation of the system is as follows: If subscriber A desires to talk with subscriber B, he lifts his telephone receiver C from the switch-hook G and thereby closes the circuit of battery 4 5 through conductor C contact N0 Spring 0, limb K of the telephone line, sub-station A, limb I of the telephone line, spring L, contact M, and lamp.

13 thus allowing current to flow through lamp B and light same, and thereby convey to the operator the signal for connection. The operator thereupon lifts answering plug 10 and inserts same into a spring jack 2 of line A, which closes the circuit of battery 5 through impedance coil M tip strand C jack spring U, winding Q; of cut-oil relay 1, limb K of the telephone line, sub-station A, limb I of the telephone line, winding P of relay 1, jack spring V,, sleeve strand 1),, winding K, of supervisory relay 7, and conductor Y thereby energizing relay 1 and causing its armature r to be attracted, thus disengaging springs O and IJ from contacts N and M, respectively, and thereby disconnecting the central source of signaling current and the line signal lamp B, from the talking telephone line. The circuit through lamp B is now broken at contact M and consequently the line signal is extinguished. Supervisory relay '7 is now energized with current from battery 5, as above described,

and thereby keeps the contact F, E, open, thus preventing the supervisory signaling device W from displaying a signal.

The operator then depresses her listening key 12 and thereby connects her telephone set for use, in a manner well understood. In depressing the listening key 12 the operator disengages springs L, and It, from contacts J and P respectively, and thereby cuts the central source of current from one talking conductor of the calling plug 11 and breaks the continuity of one of the talking strands, at contact P which stops conversation from one subscribers line to another, when the connecting plugs are connected with the respective lines, While the listening key 12 is depressed. It will thus be seen that it is impossible for the operator to listen in on the lines while conversation is being carried on therebetween, without breaking the talking circuit between the said lines and thereby stopping conversation between the subscribers.

After learning that subscriber B is the subscriber called for, the operator tests the line of subscriber B, to ascertain whether it is busy or not. In making the busy-test herein shown, the operator touches the tip E, of calling plug 11 to the ring IV of a multiple jack 2 of line B, while the listening key 12 is depressed, which closes a circuit from pole D of battery t through impedance coil A receiver G,, contact K spring I contact spring M tip strand F ring N of a jack of line B, conductor X, winding 1 of relay 3, contact M spring L relay 6, and conductor 1),, back to pole I) of bat-- tery 4, if line B is not in use. Closing this circuit from pole D, of battery 4, through the receiver G, and back to the same pole D of battery 1, does not produce an impulse through the receiver G and line 13 therefore tests clear, or not busy. If line B is in use, the rings IV IV of the multiple jacks of line B will not be at the same potential as the tip I" or calling plug 11, and hence when the tip I is touched to a ring TV there will be a flow of current through the receiver G, and hence a click in the receiver which indicates that the line is busy. Assuming that the operator finds the line of subscriber B to be not in use, she inserts the calling plug 11 into aspring jack 2 of line B. She then depresses the ringing key 13 in the usual manner, and at the same time restores the listening key 12 to its normal position. In depressing the ringing key 13, the operator closes the circuit of ringing generator 9 through contact N spring M tip strand F jack spring U belonging to line B, winding (,1, of relay 3, limb IQ of the telephone line, switch-hook G, contact H, condenser D, ringer E, limb I of the telephone line, winding P, of relay 3, jack coir tact V, sleeve strand G spring T and contact U thus ringing the ringer E which signals subscriber B, after which the ringing key 13 returns to its normal position.

Relay 3 (or relay 1) is constructed to respond to alternating, pulsating, intermittent, or interrupted currents, as well as to a continuous, direct current. To render this relay thus responsive to these different forms of currents, its armature (or armatures) is made heavy and is pivoted so that it is withdrawn from the core (or cores) of the relay slowly by gravity. The withdrawal of the armature is thus sluggish, and upon the passage of an alternating current through the windings, or winding,vof the relay, a succeeding alternation will magnetize the core (or cores) and thereby cause same to reattract the armature, before said armature has had time to be withdrawn upon the cessation of magnetism due to the immediatelypreceding alternation. The action of pulsating, intermittent, or interrupted currents on this relay, is substantially the same as the action of an alternating current. Thus when relay 3 (or relay 1) is energized by a continuous, direct current, the armature (or armatures) thereof is held continuously to the core, (or cores) of the relay by a constant magnetic pull, and when it is energized by an alternating, pulsating, intermittent, or interrupted current, the armature (or armatures) thereof is held continuously to the core (or cores) .of the relay by an intermittent magnetic pull, the pulsations of which are too rapid to permit the armature to recede from the core, (or cores) appreciably, between th pulsations.

In sending a calling current over the line of subscriber B, the operator energizes relay 3 thereof by the said current, as above described, and thus causes its armature to i be attracted and thereby disengage springs and L from contacts N, and M respectively, thus disconnecting the central source of current 4- 5 and the line signaling apparatus (in this case relay 6) from the tele phone line during the sending of the said calling current. When the ringing lrey 13 is returned to its normal position, relay 3 is de energized and springs 0 and L again engage contacts N and M,, respectively. Before subscriber B lifts his telephone receiver from the switch-hook, the circuit of the central source of current at is not closed over his telephone line, but the circuit of battery 4; is closed through conductor Y winding of supervisory relay 8, conductor 71, contact Q,,, spring T sleeve strand G jack spring V of one of a number of multiple jacks of: line B, conductor X, winding P of cut-oft relay 3, contact M spring L. the winding of relay 6, and conductor 1),. Eattery 4t does not, however allow sufficient current to flow through relays 3 and (8 to actuate their armatures, but it does allow suflicient current to flow through supervisory relay 8 to actuate same and thereby close 7 the contact between springs 13, and E as hereinbefore described, thus closing the circuit of battery 4 through conductors Y, and X supervisory signal lamp Y spring F contact E and conductor G and lighting lamp Y lVhen subscriber B answers the call and lifts his telephone receiver C from the switch-hook G, the latter is disengaged from contact H and engaged with contact F, thereby closing the circuit of bat tery 5 through impedance'coil L conductor N contact J spring L contact 0,, spring M tip strand F jack spring U, of a spring jack 2 of line B, conductor Y, winding Q of relay 3, limb K of the telephone line, switch-hook G, contact F, receiver G, transmitter J limb I of the telephone line, winding P of relay 3, conductor X, jack spring V, sleeve strand G spring T contact Q conductor Z, winding X of relay 8, and conductor Y which energizes relay 3 and causes armature T thereol to be attracted to core 8, and thereby disengage springs 0 and L from contacts N and M respec tively. The circuit through relay 6 is now broken at licl" and hence line-signal lamp B, is inoperative. The circuit of battery 5 now closed through winding X, of supervisory relay 8, energizes this relay and actuates the armature H, thereof so as to break the contact between springs F and 15,, as hereinbefore described, thus opening the circuit through supervisory lamp Y and extinguishing its signal. Subscribers A and B are now connected for conversation with each other, all of the signals being inactive.

\Vhen the conversation is completed and subscriber A hangs his telephone receiver G upon the switch-hook G, the latter is disengaged from contact F and engaged with Contact H, thereby stopping the flow of or reducing the current of battery 5 over the telephone line, in a manner well understood,

preferably by placing condenser D in the" lamp B The current from battery e now' flowing through relay 7 causes armature J thereof to close the contact between springs F and 131,, as hereinbefore described, and thereby close the circuit of battery lthrough conductors Y and X supervisory lamp W conductor H springs F, and E and con ductor G and cause lamp W to light and thereby convey to the operator the signal for disconnection.

The current now flowing through relay 1 is not sufficient to attract armature T thereof, nor sufficient to cause lamp 1?), to light. It is obvious that if subscriber A should again take his receiver from the switch-hook while connection is still made with his line, he would cause his supervisory lamp W to become extinguished. Thus by operating the switch-hook the subscriber A may signal the operator for a second connection, through the agency of the supervisory signal. It will be noted that the current which closes the contact between springs F and E of relay 7, traverses the winding K of this relay in a direction opposite to that in which the current which opens the said contact or prevents same from closing, traverses the same winding K .Vhen subscriber B hangs his telephone receiver 0 upon the switch-hook G, he breaks the circuit of battery 5 over his telephone line, in a manner similar to that just described in connection with line A, and thereby stops the flow of current through relay 3 and allows its armature to become released. lVhen armature T of relay 8 is released, it causes spring L to engage contact M and thereby close the circuit of battery t through conductor Y winding of supervisory relay 8, conductor Z, contact Q spring T sleeve strand G jack spring V of line B, conductor X, winding 1?, of relay 8, contact M springL the winding of relay 6, and conductor 1),. The current from battery a now flowing through relay 8 causes armature H, thereof to close the contact between springs F and E as here inbefore described, and thereby close the circuit of battery 4 through conductors Y and X supervisory lamp Y conductor Z springs and E and conductor G and cause lamp Y, to light and thereby convey to the operator the signal for disconnection. The current now flowing through relay 3 is not suflicient to attract armature '1, thereof, nor sufficient to cause relay 6 to actuate its armature and thereby li ht the lamp B It is obvious that if subscriber B should again operate his switch-hook while connection is still made with his line, he would correspondingly operate his supervisory signal Y,,, the same as described above in connection with subscriber A. When the operator receives bot-h disconnect signals from sulo scribers A and B, respectively, she with draws the connecting plugs 10 and 11 from their respective spring jacks, thus breaking the battery circuits through the relays 7 and 8, respectively, and thereby releasing their armatures, and at the same time restoring both telephone lines and all central station circuits and apparatus to their normal condition.

It is obvious that subscriber B may be the calling subscriber and subscriber A the called subscriber, but it is not necessary to give a detailed description of the different operations performed in thus connecting the system, as it would be practically the same as the above description wherein subscriber A is the calling subscriber and subscriber B is the called subscriber. In this case, plug 10 would be connected with line B and plug 11 would be connected with line A, and the order of operations with lines A and B would be reversed.

In Fig. 2 I have shown a single-wound cut-off relay 18 included in one limb only of the talking telephone line. This relay 18 is adapted to disengage springs O and L from contacts N and M, respectively, when the armatures thereof are attracted, and thus cut the line signal B, and the central station battery 14 from the talking telephone line.

In Fig. 3 I have shown a single-wound relay in each limb of the telephone line. I have also shown telephone instruments connected to the respective limbs of the line, and have adapted the system for party-line ringing. When the connecting plug 11 is inserted into a spring jack 2, and connection is made bet-ween switch contacts P, and (2,, the depression of ringing key 13, as described above, closes the circuit of ringing generator 9, through switch contacts P and Q contact N spring M tip strand F jack spring U, winding Q of relay 19, limb K of the telephone line, switch-hook G contact H condenser D ringer and ground N This current from generator 9 rings the bell E and simultaneously energizes relay 19 which causes its armature'to be attracted, as described above in connection with dif ferent forms of energizing currents, and thereby disengage spring 0 from contact N thus clearing limb K of the telephone line of all other circuit connections and thereby eliminating the possibility of sending a por tion of the ringing current through the cen' tral battery or circuits other than the direct line ringing circuit. When ringing key 13 is restored to its normal position, relay 19 is dee'nergized and spring 0 therefore engages contact N When the subscriber lifts his telephone receiver G, from the switchhook G he causes switch-hook G to disengage contact H, and engage contact F and thereby bridge the transmitter J and receiver C, across the limbs K and l of the telephone line, for talking purposes. vl hen the line is connected for conversation, relays 19 and 20 are both energized, thereby causing their respective armatures to be attracted and thus disengage springs O and L from the respective conductors N and M. In ringing a subscriber, if contact P, of the generator switch is connected with contact R the circuit of ringing generator 9 may be closed through ringer E in a manner similar to that just described in connection with ringer E in which case ringer E will operate and relay 20 will simultaneously actuate its armature and thereby disengage spring L from conductor M. Switch-hook Gr may be operated in a similar manner to switch-hook G and thus connect its telephone receiver C and transmitter J for con versation over the line, and also operate relays 19 and 20 as above described.

In Fig. 4 I have dispensed with one condenser in the plug-cord circuit and have connected one supervisory relay 16 from this strand of the plug-cord circuit to the middle pole of battery t 5. Then I have connected supervisory relays 15 and 17 from the other strand of the plug-cord circuit, on respective sides of condenser H to one pole of battery 5. When either plug 10 or 11 is inserted into a spring jack of an idle telephone line, the current from battery 4 will energize relay 16 and thereby cause springs W and X, to engage contacts J and K respectively, which closes the circuit of battery l through conductors N and Q contact I spring V spring 7,, contact J supervisory lamp-1V and conductor 0 and also through conductor N contact L spring Y spring X contact K supervisory lamp Y and conductor 0 thus lighting the lamps W and lVhen, however, plug 10 is connected with a telephone line and the circuit of the line is closed, the circuit of battery 5 will be closed through relay 15 and the line, as well understood, and thereby cause relay 15 to actuate its armature and disengage spring V from contact I which opens the circuit of lamp N and extinguishes its signal or keeps it from displaying a signal. If the circuit of the line is opened while such con nection is made therewith, the circuit of battery 5 will be opened through relay15, and thereby allow spring V to again engage contact I and by such engagement close the circuit of battery I through lamp as described, which then displays its signal. Relay 17 controls supervisory signal Y, in a manner similar to that just described in connection with relay 15 and signal VV and hence need not be described in detail. From this description it will be readily seen how supervisory relays 15, 16 and 17 operate and control the supervisory signals IV, and Y Of course the cord circuit of Fig. l may be used in connection with the line circuits of Figs. 1, 2 and 3, as desired. Other cord circuits also, may be used with these various line circuits.

While I have shown lamps for all central station signals, I desire it to be understoon that other forms of signaling devices, such as annunciators having visual signals, or various other forms of electrically-operable signaling devices, may be used instead.

lthile I have illustrated this invention in connection with particular types of spring jacks, connecting plugs, keys; line cut-oft relays, supervisory relays, sources of electric current, and auxiliary apparatus, I desire it to be understood that different types of these several pieces of apparatus may be used. 1

I have shown and described this invention in connection with multiple switchboard systems, but it is apparent that its features are also applicable to systems of the single, transfer, or divided-board types.

I do not wish to limit this invention to all of the particular details herein set forth, as

various modifications thereof may be made or utilized without departing from the scope of the appended claims.

lVhat I claim as my invention is:

1. The combination with a telephone line and connection terminals therefor, of a signal-controlling electromagnet normally connected with the said line, a source of electricity also normally connected with the said line, a relay for disconnecting the said electromagnet and source of electricity from the said line, the said relay being included in the talking limbs of the said line, a cord circuit terminating in a connecting plug and adapted to be conductively connected to the line, a source of electricity associated with the said cord circuit and adapted to be bridged across the metallic circuit of the line, and means for conductively connecting the last-mentionedsaid source with the said included relay, when connection is made with the line, through a portion of the metallic talking circuit including the talking strands of the cord circuit, the main terminals of the connecting plug, the main terminals of the line, and a portion of the talking limbs of the telephone line, substantially as described,

2. The combination with a telephone line and connection terminals therefor, of a sigrial-controlling electromagnet normally connected with the said line, a relay for disconnecting the said electromagnet from the line and having windings included in the talking limbs of the line, a cord circuit terminating in a connecting plug and adapted to be concluctively connected to the line, a source of electricity associated with the said cord circuit and adapted to be bridged across the metallic circuit of the line, and means for conductively connecting the said source with the windings of the said included relay, when connection is made with the line, through a portion of the metallic talking circuit including the talking strands of the cord circuit, the main terminals-of the con necting plug,.the main terminals of the line, and a portion of the talking limbs of the telephone line, substantially as described.

3. The combination with a telephone line, of connection terminals connected to the line,

a signal-controlling electromagnet normally connected with said line, a relay for disconnecting said electromagnet from the line and included in both talking limbs of the line, a cord circuit terminating in a connecting plug and adapted to be placed in conductive relation with the line, a source of electricity associated with the said cord circuit and adapted to be connected to the line, and means for conductively connecting the said source with the said included relay, when connection is made with the line, through a portion of the talking circuit including the talking strands of the cord circuit, the main terminals of the connecting club, the main terminals of the line, and a portion of the talking limbs of the telephone line, substantially as described.

i. The combination with a telephone line, of connection terminals connected to said line, a signal-controlling electromagnet normally connected with the line, a relay for disconnecting said electromagnet from the line and having windings included in both talking limbs of the line, a cord circuit terminating in a connecting plug and adapted to be placed in conductive relation with the line, a source of electricity connected to the said cord circuit and adapted to be connected to the line, and means for conductively connecting the said source with the windings of said included relay, when connection is made with the line, through a portion of the talking circuit including the talking strands of the cord circuit, the main terminals of the connecting plug, the main terminals of the line, and a portion of the talking limbs of the telephone line, substantially as described.

55. The combination with a metallic telephone line, of connection terminals at the central station connected to the line, a signal ing device normally connected to one limb of the telephone line, a signaling source of electricity normally connected to the opposite limb of the telephone line, a relay winding included in the talking circuit of the telephone line and having a switch under its control adapted to disconnect the said signaling device from the said line, another relay winding included in the talking circuit out the telephone line and having a switch under its control adapted to disconnect the said signaling source from the said line, a cord circuit terminating in a connecting plug and adapted to be placed in conductive relation with the said line, a talking source of electricity associated with the cord circuit and adapted to furnish the subscribefis station and said included relay windings with energizing current when connection is made with the line, and means for connecting the said talking source with the subscribers station, through the talking circuit including the main strands of the cord circuit, the main terminals of the connecting plug, the line terminals, the said included relay windings and the limbs of the telephone line, substantially as described.

6. The combination with a telephone line having two limbs extending to the central station, of connection terminals at the central station connected to the line, a signaling device normally connected to one limb of the line, a signaling source of electricity normally connected to the opposite limb of the line, a relay, the windings of which are included in the respective limbs of the telephone line, the said included relay being adapted to remain in an operated condition during conversation over the line, thus disconnecting and to disconnect the signaling device and signaling source from the limbs of the telephone line during conversation, a cord circuit terminating in a connecting plug and adapted to be placed in conductive relation with the line, a talking source of electricity associated with the cord circuit and adapted to furnish the windings of said included relay with energizing current dur ing conversation over said line, and means for connecting the said talking source with the subscribers station, when connection is made with the line, through the metallic talking circuit including the main strands of the cord circuit, the main terminals of the connecting plug, the line terminals, the windings of said included relay, and the limbs of the telephone line, substantially as described.

'7. The combination with a metallic, calling telephone line and connection terminals connected thereto, of a line signaling device normally connected to the said line, a source of electricity also normally connected to the said. line, a relay included in both 'alking limbs of the said line and provided with movable relay members which normally engage respective contacts but which are adapted to disengage the said respective contacts when connection is made with the line and the circuit of the line is closed, the said contacts being adapted to disconnect the said line signaling device and source of electricity from the said telephone line, a cord circuit terminating in a connecting plug and adapted to be conductively connected to the line, a central sour e of electricity associated with the cord circuit and adapted to furnish the calling line with current when connection is made with the line in response to the call, and means for connecting the last-mentioned said source with the subscribers station, when connection is made with the line, through the talking strands of the cord circuit, the main terminals of the connecting plug, the main line terminals, the said included relay, and the talking limbs of the telephone line, substantially as described.

o &

lilti- 8. The combination with a calling tele phone line and connection terminals con nected thereto, of a line signaling device normally connected to one limb of the said line, a signaling source of electricity normally connected to the other limb of the said line, relay windings included in the respective talking limbs of the said line and having switches under their control adapted to disconnect the said line signaling device and signaling source from the said line, a cord circuit terminating in a connecting plug and adapted to be conductively connected to the line, a central source of electricity associated with the cord circuit and adapted to furnish the line with current when connection is made therewith in response to the call, and means for connecting the last-mentioned said source with the subscribers station when connection is made with the line, through the talking circuit including the main strands of the cord circuit, the main terminals of the connecting plug, the main line terminals, the said included relay windings, and the limbs of the telephone line, substantially as described.

9. The combination with a calling telephone line and connection terminals connected thereto, of a line signaling device normally connected to the said line, a signaling source of electricity also normally connected to the said line, a relay, the windings of which are included in the respective talking limbs of the telephone line, the said relay being provided with movable relay members which normally engage respective contacts but which are adapted to disengage the said respective contacts when connection is made with the line and the circuit of the line is closed, the saidrcontacts being adapted to disconnect the said line signaling device and signaling source from the said line, a cord circuit terminating in a connecting plug and adapted to be conductively connected to the line, a central source of electricity associated with the cord circuit and adapted to furnish the line with talking current when connection is made therewith in response to the call, and means for connecting the last-mentioned said source with the subscribers station, when connection is made with the line, through the talking circuit including the main strands of the cord circuit, the main terminals of the con necting plug, the main terminals of the line, the windings of the said included relay, and the limbs of the telephone line, substantially as described.

10. The combination with a telephone line and connection terminals therefor, of a signal-initiating device normally connected with said line, a relay included in said line and adapted to disconnect the said device from the line when in an operated condition,

a cord circuit terminating in a connecting plug and adapted to be placed in conductive relation with the line, a talking source of electricity associated with the cord circuit, a disconnect source of electricity associated with the cord circuit and with the said device, a supervisory disconnect signal, an electromagnet through which the said sources are associated with the cord circuit, said electromagnet being adapted to control the supervisory disconnect signal, and means for closing the circuit of said disconnect source through said electromagnet when connection is made with the line and the latter is not in use, said electromagnet-circuit including a talking strand of the cord circuit, a main terminal of the connecting plug, a line terminal, a port-ion of a talking limb of the telephone line, the said included relay, and the said signal-initiating device, sub stantially as described.

11. The combination with a telephone line and connection terminals therefor, of a signal-initiating device normally connected with said line, a relay the windings of which are included in the respective talking limbs of the line, said relay being adapted to disconnect the said device from the line when in an operated condition, a cord circuit terminating in a connecting plug ancl adapted to be conductively connected to the line, a talkig source of electricity associated with the cord circuit, a disconnect source of electricity associated with the cord circuit and with the said device, a supervisory disconnectsignal, an electromagnet through which the said sources are associated with the cord circuit. said electromagnet bein adapted to control the supervisory disconnect signal, and means for closing the circuit of said disconnect source through said electromagnet when connect-ion is made with the line and the latter is not in use, said electromagnetcircuitincluding a talking strand of the cord circuit, a main terminal of the connecting plug, a line terminal, a portion of a talking limb of the telephone line, a winding of said included relay, and the said signal-initiating device, substantially as described.

12. The combination with a telephone line and connection terminals therefor, of a signalinitiating device normally connected with the said line, a source of electricity normally connected with said line, relay windings included in the respective talking limbs of the telephone line and having switches under their control adapted to disconnect the said device and source from the line, a cord circuit terminating in a connecting plug and adapted to be placed in conductive relation with the line, a source of electricity associated with the cord circuit and with the said device, a supervisory disconnect signal, an electromagnet through which the lastmentioned said source is associated with the cord circuit, the said electromagnet being adapted to control the supervisory-discos nect-signal when connection is made with the line, and means for closing the circuit of the last-mentioned said source through the said electro-magnet when connection is made with the line, the said electromagnet-circuit including a talking strand of the cord circuit, a main terminal of the connecting plug, a line terminal, a portion of a talking limb of the line, an included relay winding, and the said signal-initiating device, substantially as described.

13. The combination with a telephone line, of a connection terminal connected thereto, a signaling device and source of electricity normally connected to the line, a relay included in both limbs of the talking circuit of the line and adapted to disconnect the said device and source from the line when in an operated condition, a cord circuit, a central source of electricity associated with the cord circuit and adapted to furnish the line with current for talking purposes when connection is made therewith, means for operating the said relay from the last-mentioned said source during conversation over the line, and means for sending a calling cur rent over either limb of the line in calling a subscriber and thereby operating the said relay and thus clearing the said line of the said signaling device and first-mentioned said source, substantially as described.

14:. The combination With a telephone line, of a connection terminal connected thereto, a line signaling device normally connected to the said line, a relay included in both talking limbs of the line and adapted to disconnect the said device from the said line when inan operated condition, closing the circuit of the said line at the telephone thereof being in no way adapted to operate the said included relay when no connection is made with the said line, a cord circuit terminating in a connecting plug and adapted to be electrically connected to the said line, a calling source of electricity, a ringing key for connecting the said calling source with the line, and means for sending a calling current over the line, when connection is made with the line of a called subscriber, and at the same time actuating the said included relay by this said calling current thus sent over the talk ing circuit including a strand of the cord circuit, a main terminal of the connecting plug, a line terminal, the said included relay, and a limb of the telephone line to the telephone thereof, with a suitable return, and thereby disconnecting the said line signaling-device from the said line, substantially as described.

15. The combination with a telephone line and connection terminals connected thereto, of .a line signaling-device and source of electricity normally connected to the said line,

a relay included in both talking limbs of the telephone line and adapted to respond to continuous and to non-continuous currents and disconnect the said signaling-device and source from the line when in an energized condition, a connecting cord terminating in a connecting plug and adapted to be conductively connected to the line, a talking source of electricity normally connected to the said cord, a calling source of electricity adapted to be bridged across the talking strands of the cord circuit, a ringing key adapted to connect the said calling source with the line of a called subscriber and to disconnect the said talking source therefrom, when connection is made with the line, the said calling source being adapted to energize the said included relay when a current therefrom is sent over the line, substantially as described.

16. The combination with a telephone line, of a relay included in the talking limbs of the line, a signaling device connected with the line, a telephone connected with the line, a source of calling current, and means for sending electricity from the said source through either limb of the line and thereby giving a signal at the telephone and simultaneously causing the said relay to disconnect the said signaling device from the line.

17 The combination with a telephone line, of a relay included in both talking limbs of the line, a source of electricity and an electroresponsive device connected with the line, a telephone connected with the line, a source of calling current, and means for closing the circuit of the said calling source through the said relay, a limb of the line, and the telephone, and thereby producing a signal at the telephone and simultaneously causing the said relay to disconnect the first mentioned said source and said electroresponsive device from the line.

18. The combination with a telephone line and connection terminals therefor, of a signaling device normally connected to one limb of the telephone line, a signaling source of electricity normally connected to the other limb of the telephone line, a relay included in the talking limbs of the telephone line and adapted to respond to continuous and to non-continuous currents, to disconnect the said signaling device and signaling source from the limbs of the telephone line when in an operated condition, a cord cir cuit terminating in a connecting plug and adapted to be conductively connected to the line, a talking source of electricity normally associated with the said cord circuit, a calling source of electricity normally disconnected from the said cord circuit and adapted to transmit a non-continuous current, and a ringing key adapted to connect the said calling source to the limbs of the line of the called subscriber and to disconnect the said talking source therefrom, the said calling source being adapted to actuate the said included relay whether sent over either one, or both, of the limbs of the telephone line, with a suitable return, substantially as described.

19. The combination with a metallic telephone line and connection terminals connected thereto, of a signaling device and source of electricity normally connected to the said line, a relay th windings of which are included in the respective talking limbs of the metallic line, the said relay being adapted to respond to both continuous and non-continuous currents and to disconnect the said signaling device and source from the said line when in an operated condition, a cord circuit terminating in a connecting plug and adapted to be placed in conductive relation with the said line, a talking source of electricity normally associated with the cord circuit and adapted to furnish the subscribers station with current for talking purposes when the line is in use, a calling source of electricity normally disconnected from the said cord circuit and adapted to give a non-continuous current to operate the said included relay when a current therefrom is sent over the line of the called subscriber, a ringing key for disconnecting the said talking source from the limbs of the said line and connecting the said calling source thereto, and means for closing the circuit of the calling source through the called subscribers station over a circuit including the talking strands of the cord circuit, the main terminals of the connecting plug, the main line terminals, the windings of the said included relay, and the talking limbs of the telephone line, substantially as described.

20. The combination wit-h a metallic tele phone line and a relay included in the talking circuit thereof, of talking contacts of a spring jack connected to the respective limbs of the said line, a signaling device normally connected to the said line but arranged to be disconnected therefrom by the said included relay when the latter is in an operated condition, a central source of electricity adapted to be eonductively connected with the line and to furnish the sub-station transmitters with current for talking purposes when the line is in use, a plug provided with connection terminals and adapted to be connected with the said spring jack, a cord circuit associated with the said plug and normally connected with the said central source of electricity, a second central source of electricity associated with the said signaling device and cord circuit, and also used for testing purposes, the said sources being both used to operate the said signaling device, and an operators listening-in key adapted to cooperate with the said cord circuit in its operations, substantially as described.

21. The combination with a telephone line mally connected to the said line butadapted to be disconnected therefrom by at least one of the said included relay windings, a plu- 4 rality of talking contacts forming connection terminals for the said line, a cord circuit terminating in a connectingplug and adapted to be connected to the said line, a central source of electricity associated with the cord circuit and adapted to furnish talking current to the sub-station transmitters of the line when the said line'is in use, a central source of testing current associated with the said cord circuit and with the said signaling device, both of the said, sources being used to give the line signal, an operator s telephone set, akey adapted to connect the operators telephone-set with the said cord circuit, a testing plug provided with a test contact adapted to be placed in con-Q ductive relation with the operators telephone, and means for changing the potential of the said plurality of talking contacts of the line for testing purposes, when connec tion is made with the line, substantially as described.

22. The combination with a metallic telephone line and windings of a relay included in the talking circuit thereof, of a line signal normally associated with the said line, means for controlling the said line signal by the said included relay, a plurality of talking contacts forming connection terminals for the said line, the said terminals being arranged at the several sections of a switchboard, a plug-cord circuit, a central source of talking current associated with the plug cord circuit and normally with the said line, a source oftesting current associated with the plug-cord circuit and used for operating the said line signal, an operators telephone set, a key adapted to connect'the operators telephone-set with the said plug-cord circuit, and means for utilizing the said plugcord circuit in connection with the said talking contacts at the switchboard, substansaid line and supplied with electricity from electrical sources at the central station, a signal-controlling electromagnet normally connected to the said line but adapted to be disconnected therefrom by current in at least one of the said included relay windings, supervisory-signal-controlling-electromagnets and a supervisory signal under control thereof, a plug-cord circuit with which the said supervisory-electromagnets are associated, the said plug-cord circuit being adapted to be connected to the limbs of the said line at the said spring jacks, a central source of current associated with the plugcord circuit and normally with the line, but adapted to be disconnected from the said line by current in at least one of the said included relay windings, means for testing the condition of the line at any of the said spring acks, means for operating one of the said supervisory-signal-controlling electromagnets over a circuit including a portion of a. talking limb of the line, and means for placing at least one of the said supervisorysignal-cont-rolling-electromagnets under the control of the subscriber when connection is made with the telephone line, all cooperating for the purposes of signaling and talking, substantially as described.

2%. The combination with a metallic telephone line, of a relay the windings of which are included in the respective talking limbs of the said line, a line signaling device and source of electricity normally connected with the respective talking limbs of the line but adapted to be disconnected therefrom by the operation of the said included relay, a spring jack having aterminal for each of the limbs of the said line and connected thereto, a cord circuit normally terminating in two connecting plugs and adapted to be connected to respective spring jacks of subscribers telephone lines, a ringing key through which the limbs of the cord circuit normally extend, a listening-in key through which the limbs of the cord circuit normally extend, and which is adapted for bridging an operators telephone-set across the talking limbs of the cord circuit and in so doing breaking the continuity of one of the talking limbs of the cord circuit be tween the said connecting plugs and thereby rendering conversation between the subscribers which are connected to the said cord circuit, impossible, a source of eleotricity associated with the cord circuit, a calling source of current associated with the ringing key, and means for connecting subscribers for conversation through the said cord circuit when the said connecting plugs are connected to the said subscribers lines, substantially as described.

25. The combination in a metallic telephone system, of two subscribers lines extendin to the central station terminatin I n b l u I u in suitable respective spring acks and including a winding of a relay in each of the to be connected to the spring jacks, a central source of current associated with the cord circuit and adapted to be used for signaling and talking purposes, and means for connecting the said subscriber for conversation with each other through the cord circuit, substantially as described.

26. The combination with a metallic telephone line adapted to be included in a talking circuit, of relay winding included in the respective limbs of said talking circuit and adapted to actuate their armature when conducting a continuous or noncontinuous current over a limb of the metallic line, connection terminal for the respective limbs of said line, a cord circuit mrminating in a connecting plug and adapted to be connected with said line, a source of calling current, a ringing key adapted to connect said calling source with said cord circuit, and means for connecting said calling source with the subscribers station, when connection is made with the line, whereby at least one of the said included relay windings operates the said armature and thereby clears both sides of said line of all. apparatus and auxiliary circuits not included in the metallic talking circuit, from said connection terminals to said subscriber station, thus enabling said calling current to be sent out direct over either side of the line, with a suitable return, for party-line ringing, substantially as described.

27. The combination with a metallic telephone line adapted to be included in a talking circuit, of a line signal, a cut-oil relay the windings of which are included in the respective limbs of said line, a cord circuit, a ource of electricity, a supervisory signalcontrolling electromagnet through which the said source is associated with the cord circuit, and means for closing the circuit otthe said source through the said electromagnet and the said included windings, when the line is in use, over a portion of the main strand of the cord circuit and the talking limbs of the telephone line, substantially as described.

28. The combination with a telephone line having a limb extending to a central station, of a relay included in the said limb, a signaling device normally connected to the said limb but adapted to be disconnected therefrom by the said included relay, a plug cord circuit adapted to be conductively connected to the said line, a supervisory signal, supervisory relays associated with the said cord circuit, a divided source of electricity associated with the said cord circuit through the said supervisory relays, means for operating one of the said supervisory relays over a circuit including a portion of the path of talking currents, and means for causing the subscriber to contr l the operation of the said included relay, by opening and closing a switch at his telephone station, when connection is made with the line, and also to control the operation of at least one of the said supervisory relays during such connection, by opening and closing the said switch, to operate the supervisory signal at the central station, substantially as described.

29. The combination in a telephone system, of a line extending from a subscribers station to a central station, a relay the windings of which are included in the respective talking limbs of the line, the said relay being used as a line cut-oft relay, line signaling apparatus normally connected to the said line when the latter is not in use, but adapted to be disconnected therefrom by the said included relay when the line is in use, a subscribers sub-station associated with the said line and including a transmitter, receiver, bells, condenser and switchhook, line terminals at the central station, in the form of spring jacks, connected to the respective limbs of the said line, a cord circuit terminating in connecting plugs and adapted to be placed in conductive relation with the said line, supervisory signal-eontrolling electromagnets normally associated with the said connecting plugs, supervisory signals, an operators listeningin key, a ringing key, a calling source of electricity, and a divided source of electricity associated with the cord circuit and normally with the said line, a portion. of said divided source being adapted to furnish current for sub-station transmitters, another portion of said divided source being adapted to operate the supervisory signals, and both portions of said divided source being used for operating the line signaling apparatus and the supervisory signaling apparatus, the supervisory signal-controlling electromagnets being operated over circuits including portions of the talking conductors, all for the purpose of connecting subscribers stations together and thereby facilitating conversation between the said subscribers, and for disconnecting the said lines and said stations when same are not in use, substantially as described.

30. The combination with a telephone line extending from a substation to a central station, of a relay at the central station included in both limbs of the talking telephone line, said relay being operated only while connec tion is made with the line,a signaling circuit normally connected to the line but adapted to be disconnected therefrom by the said relay when the latter is in an operated condi tion, talking apparatus and signaling apparatus connected with the telephone line at the substation, a switch-hook at the sub-station, means for sending a calling currentthrough the said relay, the telephone line and the said sub-station signaling apparatus, thereby operating the said relay and signaling the subscriber, and means for sending a second current through the said relay, the telephone line and the said substation talking apparatus, thereby operating the said relay and supplying the subscribers transmitter with current for talking purposes, substantially as described.

31. The combination with a metallic electrical transmitting line extending conductively to a connection terminal or terminals and having one or more branch connections from the main transmission limb or limbs of the line, of electroresponsive mechanism having energizing means therefor included in both main transmission limbs of the line whereby current in either one or both of the main limbs of the line causes the operation of the said electroresponsive mechanism, the latter controlling the said branch connection or connections from the line, with respect to the main line. I

32. The combination with a metallic telephone line extending conductively to a connection terminal or terminals and having one or more branch connections from the talking limb or limbs of the line, of relay mechanism having energizing means therefor included in both talking limbs of the line whereby currentin either one or both of the talking limbs of the line causes the operation of the said relay mechanism, the latter controlling the said branch connection 01' connections from the line, with respect to the main line.

33. The combination with a metallic electrical transmitting line extending conductively to a connection terminal or terminals, of electroresponsive mechanism having energizing means therefor included in both main transmission limbs of the line whereby current in either one or both of the main limbs of the line causes the operation of the said electroresponsive mechanism, and suitable apparatus under control of the said electroresponsive mechanism.

3%. The combination with a metallic telephone line extending conductively to a con nection terminal or terminals, of relay mechanism having energizing means therefor included in both talking limbs of the line whe eby current in either one or both of the talking limbs of the line causes the operation of the said relay mechanism, and suitable apparatus under control of the said relay mechanism.

35. The combination with a telephone line, of electrcresponsive mechanism having low-resistance energizing means therefor in the path of talking currents, and suitable apparatus under control of the said electroresponsive mechanism.

36. The combination with a metallic telephone line, of electroresponsive mechanism having low resistance energizing means therefor in both limbs of the line in the path of talking currents, and suitable apparatus under control of the said electroresponsive mechanism.

37. The combination with an electrical transmitting line, ofelectroresponsive mechanism having energizing means therefor included in a main transmission limb of the line, the said mechanism being adapted to be held continuously in an operated condition by either a continuous or a non-continuone current, and suitable apparatus under control of the said electroresponsive mechanism.

38. The combination with a telephone line, of relay mechanism having energizing means therefor included in a talking limb of the line, the said mechanism being adapted to be held continuously in an operated condition by either a continuous or a noncontinuous current, and suitable apparatus under control of the said relay mechanism.

39. The combination with a metallic electrical transmitting line, of elect-roresponsive mechanism having energizing means therefor included in both main transmission limbs of the line, the said mechanism being adapted to be held continuously in an operated condition by either a continuous or a non-continuous current, and suitable apparatus under control of the said electroresponsive mechanism.

to. The combination with a metallic telephone line, of relay mechanism having ener gizing means therefor included in both talking limbs of the line, the said mechanism being adapted to be held continuously in an operated condition by either a continuous or a non-continuous current in either one or both of the talking limbs of the line, and suitable apparatus under control of the said relay mechanism.

41. The combination with an electrical transmitting line having one or more branch connections from the main transmission limb or limbs of the line, of electroresponsive mechanism having energizing means therefor included in a main transmission limb of the line and adapted to be operated by a calling current sent out over the line whereby the said branch connection or connections are disconnected from the line during the sending of the said calling current.

42. The combination with a telephone line having one or more branch connections from the talking limb or limbs of the line, of relay mechanism having energizing means therefor included in a talking limb of the line and adapted to be operated by a calling current sent out over the line whereby the said branch connection or connections are disconnected from the line during the sending of the said calling current.

43. The combination with a metallic electrical transmitting line having one or more branch connections from the main transmission limb or limbs of the line, of electroresponsive mechanism having energizing means therefor included in both main transmission limbs of the line and adapted to be operated by a calling current sent out over either one or both of the main limbs of the line whereby the said branch connection or connections are disconnected from the line during the sending of the said calling current.

4%. The combination with a metallic telephone line having one or more branch connections from the talking limb or limbs of the line, of relay mechanism having energizing means therefor included in both talking limbs of the line and adapted to be operated by a calling current sent out over either one or both of the talking limbs of the line whereby the said branch connectlon or connections are disconnected from the line during the sending of the said callmg current.

45. The combination with a metallic electrical transmitting line having one or more branch connections from the main transmission limb or limbs of the line, of electroresponsive mechanism having energizing means therefor included in both main transmission limbs of the line and adapted to control the said branch connection or con nections from the line, the said electroresponsive mechanism being adapted to be operated by calling current sent out over the line whereby the said calling current in either limb of the line causes the electro responsive mechanism to simultaneously clear the line of one or more of the said branch connections. a

4:6. The combination with a metallic telephone line having one or more branch connections from the talking limb or limbs of the line, of relay mechanism having energizing means therefor included in both talking limbs of the line and adapted to control the said branch connection or connections from the line, the said relay mechanism being adapted to be operated by calling current sent out over the line whereby the said calling current in either limb of the line causes the relay mechanism to simultaneously clear the line of one or more of said branch connections.

47. A telephone line having an electroresponsiv device associated therewith, a supervisory signal-initiating device under control of the said electroresponsive device when connection is made with the line, and means for sending calling current out over the line for signaling purposes and to actuate the said electroresponsive device.

48. A metallic telephone line having electroresponsive mechanism associated with the limbs thereof, supervisory signaling mechanism under control of the said electrore sponsive mechanism when connection is made with the line, and means for sending calling current out over either limb of the line for signaling purposes, the said current in either limb of the line simultaneously actuating the said electroresponsive mechanism.

49. The combination with an electrical transmitting line, of electroresponsive mech anism having energizing means therefor included in a main transmission limb of the line, the said mechanism being adapted to be held continuously in an operated condition by either a continuous or a non-continuous current, a connecting circuit for the line, and a signal-initiating device associated with the said connecting circuit and adapted to be placed under control of the said electroresponsive mechanism when connection is made with the line.

means therefor included in a talking limb of the line, the said mechanism being adapt ed, to be held continuously in an operated condition by ither a continuous or a noncontinuous current, a connecting circuit for the line, and a signal-initiating device associated with the said connecting circuit and adapted to be placed under control of the said relay mechanism when connection is made with the line.

51. The combination with a metallic electrical transmitting line, of electroresponsive mechanism having energizing means therefor included in both main transmission limbs of the line, portions of the said mechanism being adapted to be held continu-- ously in an operated condition by either a continuous or a non-continuous current in either one or both of the limbs of the line, a connecting circuit for the line, and a signal-initiating device associated with the said connecting circuit and adapted to be placed under control of the said electroresponsive mechanism when connection is made with the line.

52. The combination with a metallic telephone line, of relay mechanism having on ergizing means therefor included in both talking limbs of the line, portions of the said mechanism being adapted to be held continuously in an operated condition by either a continuous or a non-continuous current in either one or both of the limbs of the line, a connecting circuit for the line, and a signal-initiating device associated with the said connecting circuitand adapted to be placed under control of the said relay mechanism when connection is made with the line.

53. The combination with an electrical transmitting line having one or more branch connections from the main transmission limb or limbs of the line, of electroresponsive mechanism having energizing means therefor included in a main transmission limb of the line and adapted to be operated by a calling current sent out over the line whereby the said branch connections are disconnected from the line during the sending of the said calling current, aconnecting circuit for the line, and a signal-initiating device associated with the said connecting circuit and adapted to be placed under control of the said electroresponsive mechanism when connection is made with the line.

54-. The combination with a telephone line having one or more branch connections from the talking limb or limbs of the line, of relay mechanism having energizing means thereforincluded in a talking limb of the line and adapted to be operated by a calling current sent out over the line whereby the said branch connections are disconnected from the line during the sending of the said calling current, a connecting circuit for the line, and a signal-initiating device associated with the said connecting circuit and adapted to be placed under control of the said relay mechanism when connection is made with the line.

55. The combination with a metallic electrical transmitting line having one or more branch connections from the main transmission limb or limbs of the line, of electroresponsive mechanism having energizing means therefor included in both main transmission limbs of the line and adapted to be operated by a calling current sent out over either one or both of the main limbs of the line whereby the said branch connections are disconnected from the line during the sending of the said calling current, a con necting circuit for the line, and a signalinitiating device associated with the said connecting circuit and adapted to be placed under control of the said electroresponsive mechanism when connection is'made with nal-initiating device associated with the said,

connecting circuit and adapted to be placed under control of the said relay mechanism when connection is made with the line.

57 The combination with a metallicelectrical. transmitting line having one or more branch connections from the main transmission limb or limbs of the line, of electroresponsive mechanism having energizing means therefor included in both main transmission limbs of the line and adapted to control the said branch connection or connections from the line, the said electroresponsive mechanism being adapted to be operated by calling current sent out over the line whereby the said calling current in either limb of the line causes the electroresponsive mechanism to simultaneously clear the line of one or more of the said branch connections therefrom, a connecting circuit for the line, and a signal-initiating device associated with the said connecting circuit and adapted to be placed under control of the said electroresponsive mechanism when connection is made with the line.

58. The combination with a metallic tele phone line having one or more branch connections from the talking limb or limbs of the line, of relay mechanism having energizing means therefor included in both talking limbs of the line and adapted to control the said branch connection or connections from the line, the said relay mechanism being adapted to be operated by calling cur rent sent out over the line whereby the said calling current in either limb 01''- the line causes the relay mechanism to simultaneously clear the line of one or more of the said branch connections therefrom, a connecting circuit for the line, and a signalinitiating device associated with the said connecting circuit and adapted to be placed under control of the said relay mechanism when connection is made with the line.

59. A telephone line circuit for signaling a central station, a relay associated with the line, a normally-open branch circuit from the said line circuit containing a winding of the said relay, a line signal under control of the said relay, and means for closing the said normally-open branch circuit when con nection is made with the line whereby the said relay Winding is then placed in the talking circuit.

60. A telephone line circuit for signaling a central station, a relay associated with the line, a normally-open branch circuit from the said line circuit containing a winding of the said relay, a line signal under control of the said relay, and means for closing the said normally-open branch circuit through a connection terminal when connection is made with the line, to atlect the condition of the said relay and place the said rela winding in the talking circuit.

61. A telephone line extending from a substation to central station, a connecting circuit for the line, a normally non-polarized supervisory relay associated with the connecting circuit exterior of the talking circuit and constructed so that one operation thereof is caused by current therethrough in one direction, and another operation thereof is caused by current therethrough in the opposit-e direction, suitable electrical supply, a slgnahng device under control of the said relay, and means for supplying current to i the said relay over a portion of the line in opposite directions to cause the relay to operate and control the said signaling device.

62. An electrical transmitting line extend ing from a substation to a central station, a connecting circuit for the line, a normally non-polarized electrically-operable device associated with the connecting circuit oxterior of the main circuit and constructed so that current sent therethrough in opposite directions causes diil'erent operations there of, an electroresponsive device under control of the said electrically-operable device, and means for supplying current to the said electrically-operable device over a portion of the line in opposite directions, to control the said electroresponsive device.

(53. The combination with a telephone line and a connecting circuit therefor, of a normally non-polarized supervisory relay associated with the connecting circuit exterior of the talking circuit and constructed so that different opemtions thereof are caused by opposite energizations thereof, a signaling device under control of the said relay, and means for supplying current to the said relay over a portion of the line in opposite directions to cause the relay to operate and control the said signaling device.

64-. The combination with an electrical transmitting line and a connecting circuit therefor, oil a, normally non-polarized electrically-operable device associated with the connecting circuit exterior of the main circuit and constructed so that diilerent operations thereof are caused by opposite energizations thereof, an electroresponsive device under control of the said electricallyoperable device, and means for supplying current to the said electrically-operable device in opposite directions, to control the said electroresponsive device.

35. In a telephone system, the combina tion with a telephone line having a line signal, of acord circuit for establishing connection with the line for conversation, a cut-off device associated with the line and adapted when operated to render the line signal inoperative, a supervisory relay associated with the cord circuit, a suitable signal adapted to be controlled by the supervisory relay, and means for establishing a path for current through the supervisory relay and the said cut-01f device when connection is made with the line, the current in the said path being in one direction when the subscribers telephone is on its hook, whereby the supervisory relay is caused to display its signal, and in the opposite direction when 66. A telephone line circuit for signaling a central station, a relay associated with the line, anor1nallyopen branch circuit from the said line circuit containing a winding of the said relay, a signaling device under control of the said relay, and means for closing the said normally-open branch circuit when connection is made with the line whereby the said relay winding is then placed in the talking circuit.

67. A telephone line circuit for signaling a central station, a relay associated with the line, a normally-open branch circuit from the said line circuit containing a winding of the said relay, a signaling device under control of the said relay, and means for closing the said normally-open branch circuit through a connection terminal when connection is made with the line, to affect the condition of the said relay and place the said relay winding in the talking circuit.

(58. A. telephone line having an electroresponsive device normally associated therewith at a central station, and means for sending calling current out over the line for signaling purposes, the said calling current simultaneously actuating the said electroresponsive device.

69. A metallic telephone line having electroresponsive mechanism normally associated with the limbs thereof at a central statron, and means for sending calling current out over the limbs of the llIIGfOI signaling purposes, the said calling current in either limb of the line simultaneously actuating the said electroresponslve mechanism.

70. The combination with a telephone line, of relay mechanism having low-resist- As inventor of the foregoing I hereunto subscribe my namein the presence of two subscribing witnesses, this 16th day of June, A. D. 1904. r 7

FREDERICK R. PARKER. Witnesses: I

R. G. PARKER, WM. F. VioLn'rr.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner Washington, D. U.

of Patents,

Images