US1280395A - Universal cord-circuits. - Google Patents

Description

A. J. CARTER.

UNIVERSAL CORD CIRCUITS.

APPLICATION FILED JUNE 6.1914.

Patented Oct. 1, 1918.

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u e e ms ane henna ALVA J. :CAR'QEB; memento, .lLLlNOISQ Assienoa'io KEIiLOGG-S WIT CHBOAR-D Ann SUEPLY coiurjenmlor CI-I'IQAGQ, :LIJLLINOIS, A ooRroRATIon or ILLINOIS.

To allnuhom it'may concern Be it known that l,- ALVA Jf Clean ng, ,-a citizen of the United :States of America,

residing in Chicago county of Gook and State of Illinois; have-invented,certalnq new and useful Improvements in Universal Cord- Circuits, of which the follow-mg 11s a specification. i

rMyginvention relates to telephone 7 systems inwhich 1 uniuersalco-rd circuits are provided for interconnecting telephone lines of different characters such asmagneto and common battery lines, :one of the principal objects being to providean improyedcircuit arrangement in "the Lcord circuit whereby the connecting plugs may be insertedxintenchangeably :into lineTjacks vof the two or three-contact type of common battery lines,

or to three-contact jacks of common battery or magneto-lines and: provide the "proper supervision and talking current supply where needed. My invention :is also particularly useful in connection with UlllVBlSfil cord circuits for lnterchangeably connecting common battery and magneto telephone lines provided withthree contactjacks having the thimble connected to cut-off relays and the other two contacts extending in line conductors, the cord icircuit being provided with a three-contact plug haningdits third contact connected to' a switching relay :itdapted to be connected in series iWlth' ithe cut-off relayzand provided with circuit connectionswhereby the resulting energ ization of the switchmg relay 'Wlll connectuts winding to a talkingcontact of the plugiandithus supply talking current' to thewconnected line,"

providing it is a :common battery line; If

the plugis inserted in a magneto lineithe call signal. a

c'ut-ofi relay thereof will energize although the switching relay will not, and therefore the switching relay is not operated toHsupply;

talking current. i t

In the preferred embodiment ofinydnl mention, I provide a distinctive "signaling means whereby an! operator can distinguish calls between a magnetoi and common battery line so that 1 'case a' magneto; line Wishes to recall prior to the: removal ofltlie plug from :the answeringfjack, the super-- visory signal will flash in a distinctive man nen'so that the operator can readily distinguish when a connected magneto? line "is signaling. whether it s a disconnect ;or reuiiiv uas lrnponn-eracurrs.

"1 S p'ecificatiomof Letters Patent. 'Paflgentedflct 1, Application filed June 6,1914. Serial no. 843346.

Referring now more in detail to.one form of my invention as illustrated in the acoompanying drawing, I [show two common battery'substations A and D terminatingin the line circuits L andEL and two magneto substations B and C terminating inlinecircults L and L respectmely. A 1cord circuit ing connection be weensubstationsA and EB,

and C and D 1orconnections 'may be established between A and G, or B andD, orlikewise, connection maybe established be tween two telephones of like character. At the left of the drawing, I have shown con- Vertible :line circuits Land L for magneto and common battery lines, these line circuits comprising similar apparatus but (liffering only in connections. y a i The magneto glinc comprises awell-known magneto substation B terminating in :a line circuit L, the said "line circuit L comprising a cut-ofi relay CO, at line relay LR, a line signals, and the multiple jack J. The line circuit L is so arranged that when the hand generator at the substation B is operated the line relay "LR is energized and :then establishes alocking circuitjfor itselfto maintaln the signal S lighted unt1l an answering plug isfw nserted into the jack, (whereby the cut-off relay ,GO-isenergized. The line cirT cult L marranged so that it may beichanged into acommon battery llne c1rcu1t such as L by simplyqchanging the connections of the relaysLR and-CO as shown.

' The common battery line comprises a wellknown common battery substation A terminatingina line circuit L which comprises alcutbfi relay GOQ'a line relay LRQba-line signal S, and the multiple? jack J. The relay C0 when used ,withu a magnetoline relays and $2001 the cord circuit E when connection is :made with a line so as to connect the common battery Winding CB of the relay AS in circuit with the connected line.

At the right of the drawing I have illustrated a magneto substation C and a common battery substation D terminating in line circuits L and L The line circuit L has the usual line signal S and jacks J 2 which are shown multiply connected. The line circuit L is a twowire line circuit comprising the cut-off relay-CO line relay LR, line signal S and the multiple jack J Y The cord circuit E comprises the answering and calling plugs P and p which are connected by the heavily marked conductors, the third contact of each plug having a switching relay as SW or sw connectedto it. These switchingrelays are energized when connection is made with a common battery line soas to bridge the supervisory relays AS and CS across the connected line. The switching relays SW and 3w have a normally opencontact which is closed when the switchingrelays SW or $10 are energized by reason of connection with a common battery line to cross the ring and sleeve contacts of the con .nected plug to connect the ring and sleeve conductors so as to form a second or-sleeve conductor and also for the purpose of supplying battery for talking purposes. hen connection is made with a magneto line these switching relays are not energized and thus maintain the magneto windings M or M bridged across the line. The relays COand Q0 of magneto and common battery line circuits L and L are ofdiiferent resistances, relay CO being sufficiently high to'pre'vent the operation of the relay SW and relayCO of the common battery line being of a low enough resistance to permit the energizfation of the switching relay SW, but in either case these relays CO or CO: operate. V

I arrange the supervisory slgnals as SS so that an operator can readily distinguish what kind of a line isconnected with the corresponding end of the cordcircuit. When a common battery line is connected a switching relay as SW is operated, the supervisory signal as SS being then controlledthrough the resistance B. This resistance lt'being of.

low enough resistance allows the signal SS to glowbrightly. When a magneto line is 7 connected the switch ng relay lsnot energ zed, and the supervisory slgnalSS 111-- cluded' in series circuit with itsassociated winding CB which is of a higher resistance than its associated 'reslstance R so that the signal SS glows less brightly.

. Now if a subscriber on a common battery line wishes .to recall, the relay AS or US as the'case may be,'i s operated to flash the signal SS or SS, when the switchhook is operated or winked at the calling substation.

Now if the subscriber 'ona 'magneto liner wishes to recall, the relay AS or CS as the case may be, is operated by current from the hand generator at the magneto substation and then locks its armature with its associated signal connected in series withits associated winding CB. Upon further actuation of thehand generator at the substation, a

flow of alternating current passes through the winding M of the associated supervisory relayproducing an induced current flow in its associated winding OB and causes a flickering of the signal SS or SS, as the case may be. "Even though thesupervisory relay is locked, when a disconnect signal on the" magneto line is received, a subscriber is still able to. causea distinctive operation of the signal when he wishes to recall or attract the operators attention. I:

In regard to the various resistance values used in-the control of the switching and signaling circuits, I have found in practice that with the following values successful operation is secured. Relay GO, 1000 ohms, each winding500 ohms, relay CO" 250 ohms, and relays SWand sec, 100 ohms. By using a ohmresistance R and l00 ohms for resistance of. the winding GB of the supervisory ingrelay sw and cut-off relay CO operate.

' Havingdescribedingeneral the apparatus as'illustratedinthe drawing, the operation of the system will now be described.

Assuming that a call is initiated at the magneto su'bstationB, the substation generator is operated, current flowing over a circuit in eluding the line relay :LR which energizes closing a: locking circuit for itself through its contacts 1 and 2 and contact 10 of the relay Q0. The closing of contact2of relay LR lightsthe signal S which remains lighted due tolthe locking circuit of relay LR. The

operator noting the signal inserts the an-: swering plug P into the ack J of the calling. line, this-operation connecting the switching relay-SW and cut-off relay CO in series.

This permits the operation of the cutoff.

relay CO from; battery through the winding of the switching] relay SW, through: contactsof the plug P. and jack J, thewinding of cut-off relay toground. But due to the high resistance of relay CO, as previously described, 3 the relay SW; .does not operate:

The energization of relay CO opens the locking circult of. the relay LR which deinergizes and e'ffaces the signal S andidue to the relay 8w in lt'act that the switching relay does not 111g plug pinto the jack J closing a circuit for the cut-Oil relay CO and the switching series causing the operation of both of these relays, The operationof cutoff relay CO extends the talking conductorsof the cord circuit E to the called line. The operation of the switching relay aw closes a circuit. for the supervisory si nal SS fromibattery throughthe signal S, normal contact 4 of the supervisory relay CS, alternate contact 3 ofthe relay, 8w through resistance R to ground causing a bright glow of the supervisory signal SS. The operator their throws her ringing key RK to ring the called-for subscriber, and due to the crossing of the sleeve and ring contacts of the plugp by the closing of alternate contact 5 of the switching relay aw, battery is supplied tothe called line through the relay sw and WllBllthE subscriber answers due to the signal causedby the actuation of the ringing key RK, currentflows over thecalled line returning over the tip conductor, alternate'contact 6 of the switching relay 810 and the winding GB of the relay CS to ground. This energizes the relay CS and opens the circuit of the signal 4 SS at normal contact 4C, efi'acing the signal.

. relay AS The substations B and D are now connected in conversational circuit, said circuit being traced over the heavily marked conductors. When conversation is completed the sub scriber at the calling magneto substation B operates his hand generator causing the flow o'f current through thebridged winding M of the relay AS closing its alternate contact 7, thus establishing a locking circuit for relay AS'tra-ced from batterythrough the signal SS, alternate contact 7 the normal contacts 8 and 9 of the listening keyLK, normal con tact 11 of relay SlV. and the Winding CBof relay AS to ground Thesignal SS is in cluded in circuit with the winding CB or the so that a dull glow of the lamp SS is obtained which notifies the operator that this signal ;is received from a magneto substation; The disconnect signal from the commonbattery substation D is obtained the subscriber at subStation'DLlQP acing his receiver, which actinterrupts theflo'w of iciirrent through 'the winding CB of relayCS.

, but rel aysfsw and C0 are still niaintainedenergized over the previously traced circuit and upon de'e' nergization ofrelay CS its normal contact a is again closed connecting the sigthe jacks J and J subscriber-.1) Wishes to recall.

nal SS, ,and resistanceR in series thus lighting thelamp brightly and indicating to the operator that a disconnect signal has been received from a commonbattery subscriber; The operator now withdraws the answering and calling plugs and P. from a The Withdrawal of the plug 39 effects the restoration of the relay 8w, restoring said relay and efl'acing the signal SS. The relay AS wasenergized and locked up over thelocal circuit including normal contacts 8 and 9 of the listening key LK and in order to eflect the restoration of the relay AS the operator actuates the listening'key LK to interrupt the circuit of relay at the normal contacts 8 and 9 and saidrelay AS restores efi'acing thesignal SS.

Now if the subscriber at substation B wishesito recallorconverse with the operator before the removalof the answering plug P from the ack a continued operation of the hand generator at substation 13 transmits an alternatingcurrent through the magneto Winding M of the supervisory relay AS. An induced currentis set up in the winding GB of supervisory relay AS and this winding being included visory signal SS a flickering efi'ect of-the lamp is produced, notifying the operator that a recall is being sent from a magneto substation. Without this distinctive feature of the signal upon recall, the operator would disconnect when a recall was desired. The operator after having 'conversed with the subscriber that sent the recall, throws her listening key LK interrupting the circuit of the relay AS, said relay restoring and etfacing the signal S'S as before described. The recall of the common battery subscriber atsubstation D is caused by the subscribers switch-hook being operated, causing the sig nal SS to flash, notifying the operator'that Now ifa call is initiated from the common battery subscriber A, upon removal of the switch-hook at substation A, the line relayLR' is energizedclosing its alternate contact 2' tolight the line signal S. The operatornoting the'lighted' signal S inserts the answering plug P into the jack JWOt the calling line. This insertion oitthe plug P into the jack energizes the cut-01f relay (f -O andthe switching relay 3 SW in series. Responsive to the energization of the switching relay SVV' its alternate contact 12 is closed-thereby connecting the sleeve and ring contactsot the plug P so that-jthebattery through the and through alternate contact 1301:" relay SW through the common battery winding GB of relay AS to ground, causing the energization of the supervisory relay AS; When the switching relay SW is energized the closing of its alternate contact 13 disconnects in circuit with the super relay S'W will flow over the calling line returniing over the tip conductor the magneto Winding of the supervisory relay AS from the cord circuit and connects the common battery winding GB of the relay into the jack J 2 0f the magneto line, and the insertion ofthe plug disconnects the line signal S and as thesleeve of the jack J 2 is on open clrcuit, no circuit isestablished for the switching relay 8012, this relay remains deenergized and maintains its magneto Winding M of the calling supervisory relay CS in bridge of the calledline. The operatornow actuates, her ringing key RK to ring the bell of thecalled-for subscriber at magneto substation C, and upon the removal of the receiver at substation C, the lines are connected in conversational circuit, which may betraced over the heavily marked conductors. When conversation is completed the subscriber at magneto substation C operates the hand generator at thesubstation G, causing the signal SS" to light with a dull glow for the same reason as previously de scribed and the restoration of the receiver at substation A causes the signal SS to light and glow brightly. The disconnection and restoration of the apparatus to normal is the same as before described, the operator actuates her listening key LK to interrupt the normalcontacts l l and 15 to interrupt the circuit of relay CSand elface signal SS.

In case of either subscriber wishin to recall before the plugsare withdrawn the operation of the signals SS and SS are the same as previously described" a Should connection be established between the substations A and B, the operation of thecircuit can be men -followed from the previous description, and i tion be established between substations C and B or to substations of likecharacter such as to common battery or. two magneto substations, the operation can also be readily followed from the description already given. a "While I have described 'my invention in one specific form and, have given certain values for a successful operation, I do not wish to, be limited to the same as I contemplate changes which will, readily .suggest themselves to thoseskilled in the art, and I aim to cover all such modifications in the appended claims Having described my invention, what I claim as new and desire to secure by United States LettersPatent is: r i a 1. A telephone system comprising tele phone lines provided with two and three contact jacks, a cord circuit for interconnecting said lines provided with a plug havlikewise if connec ing three contacts, a switching relay connected to the third contact of said plug and operated responsive to a connection of said plug to said jack for electrically" connecting said third contact and a talking contact of the associated plug to supply talking current through the winding of s aid switching for re 'isterin with said Tacks talk is v e r a two of the v plug contactsand a switching relay connecte ed to the third contact of the 'plug, said switch ng and l cut-ofi relays being energized respons ve to aconnecti'on oftlie plug and jack, said switching relayhaving contacts closed" responsive to its ener'gization for electrically connecting one of said plug talking contacts to the said third contact thereof to supply current through the winding of the switching relay to the connected line. 7

3. A telephonesyste n comprising telephone lines' having three sonnet jacks, a cut-ofi' relay connected: to one ofthe jack contacts andline conductors extending from theother two contacts thereof, a cord circuit having a three-contact "plug for registering with said jacks, talking conductors extending from two of the plug contacts and a switching electromagnet connected to the third contact of the plug, a source of current connected to the winding of said switching electromagnet whereby said switching magnet and "cutoff relay are energized responsive toja connection'of theplug and jack,

and contacts controlled by said switching magnet for electrically connecting one of said plug talking contacts and the third contact thereof whereby talking current, is

supplied to the connected line through the winding of said switching electromagnet.

4. A telephone system comprising telephone lines having two and three contact jacks, a cut-0T1" relay-normallyconnected to a contact of each jack, a-cord circuit having athree' contact plugadapted'for connection with any of said jacks, a switching electroinagnet connected to onc of said contacts of rue of each jack, a universal cord circuit for interconnecting sa1d l1nes having three contact plugs adapted for connection with any of said jacks, one of the contacts of each plug being adapted to register with the said jack contents to which the source of current is connected, a switching electromagnet connected to each such contact of the plug and connected to the other pole of said source whereby it is energized responsive to the connection of its plug with one of said jacks, and means controlled by each electromagnet when so energized for directly electrically connecting the said connected plug contact to one of its associated contacts and for closing a supervisory circuit.

6. A telephone system including telephone lines having three contact jacks, a cut-off relay connected to one of the ack contacts, a cord circuit having a three-contact plug for registering with said jacks, a switching relay connected to a contact of the plug, a supervisory relaylprovided with a winding having its terminals connected to the other two contacts of said plug, a circuit including said switching relay and. said cut-oii' relay adapted to be closed responsive to a connection of the plug and jack, and contactscontrolled by said switchingrelay for interrupting a circuit through the supervisory relay and for connecting one of said plug contacts to the said third plug contact whereby current is supplied to the connected line through a winding of the switching relay.

7. A telephone system including telephone lines having three contact jacks, a cut-01f relay connected to one of the jack contacts,

a cord circuit having a three-contact plug for registering withsaid jack, a switching electromagnet-connected to a third contact of said plug, a double-wound supervisory relay having one winding bridged across the talking contacts of said plug, a circuit including said cut-off relay and said switching relay adapted to be closed responsive to a connection of the plug to the jack, and contacts controlled by said switching relay for interrupting the bridging circuit of said supervisory relay and for connecting one of the plug contacts to a terminal of the other winding of said supervisory relayand for connecting the other of the talking contacts of the plug with said switching electromagnet.

8. A telephone system including a telephone line terminating in a jack at the cen tral exchange, a cord circuit provided with a three-contact plug for registering with said jack, a switching relay connected to the sleeve contact of said plug, an energizing circuit for said switching relay closed responsive to the insertion of said plug in said jack, and contacts controlled by said switching relay for connecting said switching relay in multiple with another contact of said lug.

9. A telephone system including a telephone line terminating at the central exchange in a jack, a cord circuit provided with a three-contact plug for registering with said jack, a switching relay connected to the third contact of said plug, an energizing circuit for said switching relay closed responsive to the insertion of said plug in said jack, a supervisory relay, and contacts controlled by said switching relay for con necting one terminal of said supervisory relay to one of the talking contacts of said plug and for connecting said switching relay to the remaining contact of said plug.

10. A telephone system including a subscribers telephone line terminating in a jack, an operators link circuit provided with a three-contact plug for registering with said jack, a battery, a switching relay having one of its terminals connected to said 7 scribers telephone line terminating in a jack, a link circuit provided with a threecontact plug for registering with said jack, a battery, a switching relay, and means individual to the link circuit for connecting said battery through said switching relay to two of the contacts of'said plug.

12. A telephone system including a subscribers telephone line terminatingin a jack at the central exchange, an operators link circuit provided with a plug for registering with said jack, a battery, a relay winding, and means individual to the link circuit responsive to the connection of the said plug to the said jack for connecting said battery through said relay winding to a plurality of said contacts'of the plug.

Signed by me at Chicago, in the county of Cook and State of Illinois, in the presence of two witnesses.

, ALVA J. CARTER. Witnesses GEORGE E. MUELLER, M. R. Roonroim.

Gopies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G.

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