US1127005A - Telephone system. - Google Patents

Telephone system. Download PDF

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Publication number
US1127005A
US1127005A US80226913A US1913802269A US1127005A US 1127005 A US1127005 A US 1127005A US 80226913 A US80226913 A US 80226913A US 1913802269 A US1913802269 A US 1913802269A US 1127005 A US1127005 A US 1127005A
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circuit
station
car
und
line
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US80226913A
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Clarence L Howk
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AT&T Corp
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Western Electric Co Inc
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/02Constructional features of telephone sets
    • H04M1/18Telephone sets specially adapted for use in ships, mines, or other places exposed to adverse environment

Definitions

  • each raiiu'ny car jacks Wheneby, upon the ilimrim; herein 0f the plugs nsuciuted with a cord, one into u jack oi one car und the @113er into a jack of another, eonnectiuu is esmblished therebetween, permitting communication to be had between stations in the two cars su emr nested.
  • Each car is also provided with a receptacle Containing jacks, whereby, upon the opening off said receptacle und inserting a plug associated with ene-end of a.
  • mmmunication may be had with either a commun buttery or iocal battery 1in@ or a line over which direct current is used for uignuing, sua-h for example as n train ,mnchng iine.
  • the telepnuue :Q z'steni of nach cur is arranged for commuuicuiun hutu'en stations in the same cnr, und mure ripening of the receptacle nutoinut-iuuiiy @hngen circuit conditions, adapt ing emi-h our v upmeu'r, im' Cunnuuuicution with outside nes.
  • Fig. 2 is a diagram of the circuit. in such uur
  • Fig. 3 is a diagram of the talking circuit hutu'een two Stations in dierent cars
  • Fig. 1 u diagram of the talking circuit between n station in one cur and n. common battery exchange
  • und Fig. 5 is n view in perspective of the receptacleprovidcd on nach car, showing n switch which numnti any Changes circuit conditions upon oper. ing the reptacie.
  • the teephunesyatem or exchange 'equipmentl for each railway czar comprises u plurality of stations 1G, 10, cnnnected by menusv of conductors 11, 12, 121 and. 11, with une another and with the t/eephuuic apparatus common o all stations 10cm/ed in un apparatus box 15, mounted in the uur.
  • Located under the cnr is u receptacle 16 cnuuinin jacks connected with the uypuraus luwte( in the apparatus box 15 by means of conductors 17, 18, 19 und 20.
  • n jack 25 and .u switch 'The station appnrutus may consist of n hund set ZT comprising :1 transinitier 25, u receiver 29 und u switch 30 ab tuched to one end of u cord 31, the other end of which terminates in u plug 32, adapt- Qd for connection with the jack 25.
  • Located in the apparatus box 15 is un in duction coi 33, the primary 31 of which, iu series 'with n transmitter buttery 35, is bridged acruas the conductors 13 and 14.
  • the secundnry Winding 3G of the induction coi 33 is located in the receiver circuit.
  • relay 40 is in series with a battery 41 and the conductors 12 und 13, the circuit baing nox-many open at the switches 26.
  • This interrupter being of well known construction, is a device for producing, from a Vdirect current source, currents for operating the usual telephone line signals..
  • jacks 55 and 56 Located in the receptacle 16, are jacks 55 and 56, the former being adapted for making connections to common battery lines and the latter for making connections to local battery lines or lines over which direct current is used for signaling.
  • Bridged across conductors 19 and 20 and inseries with a condenser 58, of small capacity, is a switch 59 which is normally closed when the receptacle 16 is closed, and open when said receptacle is open.
  • the switch 59 which may be of any suitable construction, is so mounted in the receptacle 16 that when a door 60 thereof (see Fig. 5) is closed, said switch is closed, and open when said door is open.
  • the door 60 of the receptacle 16 is only opened when connection is to be made to an outside line and remains open during the time such connection is established.
  • the condenser 58 of the exchange equipment in each car normally completes the talking circuit therein. When, however, connection is established between the exchange equipments of two similarly equipped cars, the condensers 58 are bridged across the line and prevent the said line from bein short circuited. These condensers being o small capacity do ⁇ not interfere with the transmission between stations.
  • a ringer 65 which is in series with a condenser 66 and is normally bridged across the conductors 17 and 18 and across the conductors 19 and 20.
  • a jack 67 which is bridged across the conductors 19 and 20.
  • each car is provided with a cord having attached thereto, at each end, a plug 76 adapted for insertion into the jacks 67 in the ends of the cars.
  • each car is provided with a line pole and cord 85 having one end terminating in hooks or other suitable devices for connecting with the line wires, and the other end in a plug for in sertion in the jack 56, shown diagrammatically by dotted lines in Fig. l.
  • connection When connection is to be established between the car and a telephone exchange, the car will be located near a jack in which terminates a pair of line wires from the exchange, and therewill be located at the jack a cord having a plug attached to each end thereof, so that it is unnecessary to equip the car with a cord for thisfpurpose.
  • Connection to a common battery exchange is established by connecting a plug and cord to the jack 55, and to a local battery exchange thrugh the jack 56.
  • the jacks 55 and 56 are of dii'ercnt characters so as to ⁇ receive only a plug of particular construction and, to enable the proper connection to be established readily, all plugs associated with a jack from common battery exchanges will be of a construction suitable to enter the jacks whilethose associated with a jack from local battery exchanges' will be of a construction suitable to enter the jacks 56.
  • the signaling from station tostation'in the same car or from a station 1n one car to a station in another car is accomplished by means of a buzzer circuit or circuits which may be of any well known construction.
  • the switch of the hand set 27 is operated, thereby closing the battory circuit and actuating the usual ex change signal.
  • H it is desired to signal a station in the cur'ffn 'tho climbing@ the usuel generator current is sent over the line xii-cs operating the ringer in the car.
  • the connecting devices oi the pole und cord S5 are caused to engage thcy wires of said line, the door 60 of the receptacle 16 is opened and the plug associatcdu'lth the said pole and cord 85 is inscrled into' the' jack Should the connection .he established with u local battery exchange, he operations Awould. be similar, using the cord associated with the jack in which terminato the line wires from the local buttery exchange instead of the plug und cord 85.
  • an exchange equipment carried by eac-h oar adapted for both interconnection and connecgtion to outside lines, means normally in circuit with said equipment for changing circuit conditions when interconnection is established, outside telephone lines of di-lerent characters, means for connecting said exchange equipment and any of saidL outside lines, and means operated in establishing connection ioetween said equipment and any of' said outside lines for conditioning the talking circuit therebetween for operation.
  • a telephone system for trains, an exchange equipment carried by each car adapted for both interconnection and connection to outside lines, means normally in circuit with said equipment for preventing the short ciicuiting of the line when interconnection is established, and means operated in establishing connection between said equipment and an outside line for discon necting said short ciicuiting preventative means.
  • a telephone system for trains an exchange equipment carried by each cai' adapted for both intercomiection and connection to outside lines, a condenser norn maily in circuit with said equipment, which, when interconnect-ion is established, prevents the sliort circuiting of the line, and. a switch normally i-n circuit with said equipment., which5 (inging theestafblishing of connection to an outside line5 is operated to remove said condenser from the circuit.
  • a telephone system foi trains, an exchange equipment carried by each car adapted for connection vfrom station to station within the same car and for connection 3Detion within the same car, for connection between stations in different cars and for connection to outside lines, means normally in circuit with said equipment to complete the talking circuit from station to station in the same car, means for connecting together a plurality of said equipments and for changing the relation of said iirst mentioned ineens to said equipments, and means 0pelated in establishing connection oetWeen said equipment in one car and an outside line for removing said first mentioned means from the circuit.

Description

C. L. HOWK.
TELEPHONE SYSTEM.
APPLICATION FILED NOV. 21. 1913,
Patented Feb. 2, 1915,
c. L. HowK.
TELEPHONE SYSTEM.
APPLICATION IlLED NOV.21,1l3. 1, 1 27,005. Patented Feb. 2, 191.5.
2 SHEETS*SHEET 2.
UNTED STATES PATENT OFFICE.
CMRENE L. H0153., F NEWARK. NW JERSEY, ASSLGNO TO WESTERN ELECTBXG CMEANY, 0.1? NEN YGRK, Y.
TELEPHQNE EYSTBIVI.
Mmmm,
Specification ef letters Patent,
furnlud Feb. i5, 1915.
To (1515 11i/omit may conne/m 15e known that 1, Cmunzwr. 1.. Emmi, i Citizen if the United Status, residing at rieuurk, in the county nf and ui' Naw Jerney, hav@ invented u certain new und usefu 1min-@minuut in Tniephone Sysem, 0f which the fuiiuu'ng in :i full, dem?, sonnig-sz, und @met euuripiuu.
This ,inrentiun *teu in telephone:
tunis., und mure uurnruiary w eephenn sysemu for irainrg, fue curi,- o'" which :it wguippe im' ii.-iurcnnnnuniruuiuu betwnen stations ocud therein und which zum adapted u; be commented with outside Einen .in raiwuj.' cnrs which ure equipped with wiephunu upparuus for intuicummunicutinn between dicren stations thereof, requently 'uis desired m he able tu establish cununuun-.uciun with the Leicphrme Lines :dong the rniroad right of way or to entail# ish @animation with he teiephone exchange whim thu uur is yu in the railroad yards in the city. 1t furt lermore frequently 0Q- curs that wn raiway cars, similarly equippe for miepimne emmunicugien br.-
twcen duim-ent miens nf the Same can', am
utachei to the game train, in which-cane ii is dus'irahie iu henkie to huid teephone nommuuicutiun from stations in im?, cnr to those in. another. Sine/e raiway' @am are usan-By maimed. with hei having very imte knowedge of iwiep` one equipment, it is 1@- nimble that the fsssabishing` of connections from cnr tu cur, und from cnr to ouside. lines, be Asimplified anl much as poussibe.
it is the' object of vthis invention them fore in prnriie apparatus so arranged as to muet the ruquirements enumerated above.
"with this object in View, generally speak ing, there provided fm' each raiiu'ny car jacks Wheneby, upon the ilimrim; herein 0f the plugs nsuciuted with a cord, one into u jack oi one car und the @113er into a jack of another, eonnectiuu is esmblished therebetween, permitting communication to be had between stations in the two cars su emr nested. Each car is also provided with a receptacle Containing jacks, whereby, upon the opening off said receptacle und inserting a plug associated with ene-end of a. cord into the proper jack, the other end of the cord being associated with the proper line, mmmunication may be had with either a commun buttery or iocal battery 1in@ or a line over which direct current is used for uignuing, sua-h for example as n train ,mnchng iine. Normally, the telepnuue :Q z'steni of nach cur is arranged for commuuicuiun hutu'en stations in the same cnr, und mure ripening of the receptacle nutoinut-iuuiiy @hngen circuit conditions, adapt ing emi-h our v upmeu'r, im' Cunnuuuicution with outside nes.
This inwentiun wil be more fuiiy undnr Simoni by; reference o the accompanying riruwings, whernin-- Figure n, View of tun railway cars sinuiry.equsped with tuephone systems; Fig. 2 is a diagram of the circuit. in auch uur; Fig. 3 is a diagram of the talking circuit hutu'een two Stations in dierent cars; Fig. 1 u diagram of the talking circuit between n station in one cur and n. common battery exchange; und Fig. 5 is n view in perspective of the receptacleprovidcd on nach car, showing n switch which numnti any Changes circuit conditions upon oper. ing the reptacie.
As shown in the drawings, the teephunesyatem or exchange 'equipmentl for each railway czar comprises u plurality of stations 1G, 10, cnnnected by menusv of conductors 11, 12, 121 and. 11, with une another and with the t/eephuuic apparatus common o all stations 10cm/ed in un apparatus box 15, mounted in the uur. Located under the cnr is u receptacle 16 cnuuinin jacks connected with the uypuraus luwte( in the apparatus box 15 by means of conductors 17, 18, 19 und 20.
At auch stutinn, taps from the conductors 11, 1:2, 13 and 14 terminate in n jack 25 and .u switch 'The station appnrutus may consist of n hund set ZT comprising :1 transinitier 25, u receiver 29 und u switch 30 ab tuched to one end of u cord 31, the other end of which terminates in u plug 32, adapt- Qd for connection with the jack 25.
Located in the apparatus box 15 is un in duction coi 33, the primary 31 of which, iu series 'with n transmitter buttery 35, is bridged acruas the conductors 13 and 14. The secundnry Winding 3G of the induction coi 33 is located in the receiver circuit. In order to provide means -for signaling from the car to a ocnl battery exchange or ,to s, station on a train despatchng line, re-
lay 0 is mounted in the apparatus box 15, The winding of relay 40 is in series with a battery 41 and the conductors 12 und 13, the circuit baing nox-many open at the switches 26. In multiple with the winding i of relay 40 is the battery circuit 42, 43 of an interrupter 44, 'having a ringing circuit 45, 46 terminating in normally open contacts 47, 48 of the relay 40. This interrupter being of well known construction, is a device for producing, from a Vdirect current source, currents for operating the usual telephone line signals..
Located in the receptacle 16, are jacks 55 and 56, the former being adapted for making connections to common battery lines and the latter for making connections to local battery lines or lines over which direct current is used for signaling. The conductors 17 and 18, and 19 and 20, having bridged thereacross a protector 57, the middle point of which is grounded to the truck frame` of the car, terminate in the jacks 55 and 56 re-4 spectiyely. Bridged across conductors 19 and 20 and inseries with a condenser 58, of small capacity, is a switch 59 which is normally closed when the receptacle 16 is closed, and open when said receptacle is open. The switch 59, which may be of any suitable construction, is so mounted in the receptacle 16 that when a door 60 thereof (see Fig. 5) is closed, said switch is closed, and open when said door is open. The door 60 of the receptacle 16 is only opened when connection is to be made to an outside line and remains open during the time such connection is established. The condenser 58 of the exchange equipment in each car normally completes the talking circuit therein. When, however, connection is established between the exchange equipments of two similarly equipped cars, the condensers 58 are bridged across the line and prevent the said line from bein short circuited. These condensers being o small capacity do` not interfere with the transmission between stations.
ln order that the car may be signaled from an outside line when connection therewith has been established, there is mounted in the car a ringer 65, which is in series with a condenser 66 and is normally bridged across the conductors 17 and 18 and across the conductors 19 and 20. In order that connectionanay be established between two cars similarly. equipped with telephone systems, there is mounted in'each end of the car (or at any other suitable place) a jack 67 which is bridged across the conductors 19 and 20.
To enable connection to be established between two cars similarly equipped, each car is provided with a cord having attached thereto, at each end, a plug 76 adapted for insertion into the jacks 67 in the ends of the cars. Furthermore, to enable connection to be established between the car equipped with a telephone system embodying this iuvention and a line upon which there is used direct current for signaling, such as a composited telegraph circuit, a train despatching line or some similar line, each car is provided with a line pole and cord 85 having one end terminating in hooks or other suitable devices for connecting with the line wires, and the other end in a plug for in sertion in the jack 56, shown diagrammatically by dotted lines in Fig. l. In order to prevent the signaling currents over the line to which the telephone system of the car is connected from interfering with the proper working of the telephone system, aV
condenser' 73is included in series with the conductor 20.
When connection is to be established between the car and a telephone exchange, the car will be located near a jack in which terminates a pair of line wires from the exchange, and therewill be located at the jack a cord having a plug attached to each end thereof, so that it is unnecessary to equip the car with a cord for thisfpurpose. Connection to a common battery exchange is established by connecting a plug and cord to the jack 55, and to a local battery exchange thrugh the jack 56. The jacks 55 and 56 are of dii'ercnt characters so as to `receive only a plug of particular construction and, to enable the proper connection to be established readily, all plugs associated with a jack from common battery exchanges will be of a construction suitable to enter the jacks whilethose associated with a jack from local battery exchanges' will be of a construction suitable to enter the jacks 56.
The signaling from station tostation'in the same car or from a station 1n one car to a station in another car is accomplished by means of a buzzer circuit or circuits which may be of any well known construction.
With the circuit as shown in Fig. 2 and assuming that communication is desired from station A to station B in the same car, the plugs 32 having been inserted into the jacks 25 and station B having been signaled from station A over the buzzer ircuit, switches 30 of the hand sets 27 are closed,
placing the transmitters 28 across the conduc tors L; and 14 and the receivers across the conductors 11 and 14. Talking into the transmitter of station A will set up a current in a circuit which may be traced as follows: From one side of battery A 35, through conductor 78, induction coil primary 34, conductor 14, transmitter 28 of station A, conductor 13, to other side of battery 35. Current in this circuit will induce a current in a circuit including the receiver of station B, which may be traced as foin lows: From induction coil secondary 36, through conductor 70, normally closed contact 71 of relay 40, conductor 19, normally closed switch, condenser 58, conductor Q0, normally closed contact 72 of relay 40, con denser 73, conductors 74 und 1l, receiver 29 of station B, conductors 1.4 und 79, and hack Y to induction coil secondary 36.
Suppose now that railway cnrs similarly equipped with telephone' systems are adjacont in the sume train, :nid that it is de sited to be able to communicate from a sttion in one to n station in another, the plugs 76 of the cord 75 are nscrtcdin the jacks i7 in the adjacent ends of tho two cars, thereby establishing connection between the two tclcphone systems. The numlm' of con doctors torminuing in the jacks und the numhe' the corals muy he increased to ac coinmoda. the buzzer circuit conductors required for signaling purposes. The talking circuit established by the insertion of the plugs 76 into the jncls 62' of two similarly equipped cars and by the closing o switches 26 at stations in clilercnt cnrs is represented in Fig. 3.
onsidcring zum the stetion in one 'cnr us station A und tho one in the other csr as sin, tion B, speaking into the. transmitter of station i will causo current liow in' a circuit which muy he traced as follows: From' but-v tory 35, through conductor 78, inchictiou coil primary 34, conductor 14, transmitter 28 of station ...5&,concluctor i3 to the other side of battery Current iowing in this circuit will inziucc u lcurrcui, in the induc'ion coil secondary und through @circuit which muy he .truccfns foliows; From induction coil ccconfury 36, thmugh conductor et station A'ciuuluctcr SQ; induction coil secondary $36, coniucors 79 zmd'l, reccvcr 29, conductor il and corulenser T3 ai; station E; conductor Si; ioudeuser; conductor il, receiver 529., conuciors ud'unhnck to ixuiuction wil'scconciury at' A. The condcnsers hrirlgcd across iucet euch stugion nre of such?, to have a negligihlc 'eccupon .evtrunsmis- 820B. i i' 'i Aucun-ling that a cui' squippoiiwith c. telcphone system einhodyinglhis invention is temporarily stutionod ut a pointwhcrc lino conductors from u common battery tcle lione system terminato in a suitable plug an cord,"
und that.. it .is desired to establish connection between thc cui' und the telephone (exchange, the door 6) of the receptacle l5 is then opcncfl, thereby opening the iswitch 59 and removing the condenser bridge from lic-russ conductors L() und S119. 'he plug of @lic cord is now inserted int-o jack 55, estublishinnf u talking circuit such as is repror sented in Fig. Al. if it i8 desired vto signal the exchange rcpmsentcd us in Fig. 4
from station B, the switch of the hand set 27 is operated, thereby closing the battory circuit and actuating the usual ex change signal. H it is desired to signal a station in the cur'ffn 'tho climbing@ the usuel generator current is sent over the line xii-cs operating the ringer in the car. With the usual operators telephone set bridged across the linc conductors at the exolmnge, the operation of the talking circuit shown in Fig. IIl will be evident. Should .conncction he desired between the cnr und n line over which directcurrent is used for signaling purposes, the connecting devices oi the pole und cord S5 are caused to engage thcy wires of said line, the door 60 of the receptacle 16 is opened and the plug associatcdu'lth the said pole and cord 85 is inscrled into' the' jack Should the connection .he established with u local battery exchange, he operations Awould. be similar, using the cord associated with the jack in which terminato the line wires from the local buttery exchange instead of the plug und cord 85. ln fact, it muy be that in some cuscs the lino over which direct current is used for signaling muy terminate in u plug similar to that associated with a local buttery exchange. The signaling; from the local battery exchange or from u station on the line over which direct current is used for signaling `to the cur is accomplished in the sume manner as from the common buttery exchange hercinbefoz'c described. In signaling from the cur to a local battery eX chungo or to n station on the line over which direct current is used signaling, the sume operzitions are nece ry. In signaling from the station A in the car to u lino connected with the car through the jack 56. the switch 26 (see Fig. 2) is operated, thereby closing a circuit which may bo traced as follows: lFrom one side of battory 41,' through conductor 13, switch 26 at station B, conductor l2 to a point 82 therein where it divides, one part going through the winding of 'relay 4:0 and the other through the battery circuit 43, 42 of the interruptor 44, meeting at a point 83 in s. conductor 84, conductor 84 and back to the :other side of buttery 41. Current through the winding of relay 40 causes the cnergization of said relay, which thereupon attracts its armatures, closing the normally open contacts 47 und 48. Current: is flowing at the sumo time in the Battery circuit 43, 42 of the interruptor il und causes un alternating current to flow from the interruptor through conductor 45, contact 47, conductor 20, one
line yx-o to the signal at the station being sigsgna` d, the signal at said station, other line wire, conductor 19, contact 48, conductor 46 in beck to the interru'pter 44. The talking "circuit established hy the insertion of a. plug into 'lie jack 56 muy be represented in Fig. Il. the switch at station A being open and considering that one conductor of the connecting cord is connected at u. point 87 and the other at u point 86, thereby Substitutmenace ing the connected line for station B. The epe-tation of such a circuit is considered, so Weil known as to require no explanation.
iv'iiat Si claim is:
i. in a telephone system for trains, an exchange equipment carried by eac-h oar adapted for both interconnection and connecgtion to outside lines, means normally in circuit with said equipment for changing circuit conditions when interconnection is established, outside telephone lines of di-lerent characters, means for connecting said exchange equipment and any of saidL outside lines, and means operated in establishing connection ioetween said equipment and any of' said outside lines for conditioning the talking circuit therebetween for operation.
2. n a telephone system .for trains, an exchange equipment carried by each car adapted for both interconnection and connection to outside lines, means normally in circuit with said equipment for preventing the short ciicuiting of the line when interconnection is established, and means operated in establishing connection between said equipment and an outside line for discon necting said short ciicuiting preventative means.
In: a telephone system for trains, an exchange equipment carried by each cai' adapted for both intercomiection and connection to outside lines, a condenser norn maily in circuit with said equipment, which, when interconnect-ion is established, prevents the sliort circuiting of the line, and. a switch normally i-n circuit with said equipment., which5 (inging theestafblishing of connection to an outside line5 is operated to remove said condenser from the circuit.
4. ln a telephone system foi trains, an exchange equipment carried by each car adapted for connection vfrom station to station within the same car and for connection 3Detion within the same car, for connection between stations in different cars and for connection to outside lines, means normally in circuit with said equipment to complete the talking circuit from station to station in the same car, means for connecting together a plurality of said equipments and for changing the relation of said iirst mentioned ineens to said equipments, and means 0pelated in establishing connection oetWeen said equipment in one car and an outside line for removing said first mentioned means from the circuit.
In witness whereof, hereunto subscribe my name this 18th day' of November, A. il, l9l3.
CLARENCE L. HOWK.
Ni tnesses z Nason E. TUTHILL, Amon HAZLEY.
US80226913A 1913-11-21 1913-11-21 Telephone system. Expired - Lifetime US1127005A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2868879A (en) * 1957-03-29 1959-01-13 Berman Martin Plug-in portable telephone system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2868879A (en) * 1957-03-29 1959-01-13 Berman Martin Plug-in portable telephone system

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