US1166466A - Automatic telephone system. - Google Patents

Automatic telephone system. Download PDF

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US1166466A
US1166466A US1543715A US1543715A US1166466A US 1166466 A US1166466 A US 1166466A US 1543715 A US1543715 A US 1543715A US 1543715 A US1543715 A US 1543715A US 1166466 A US1166466 A US 1166466A
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switch
sequence
finder
circuit
contact
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US1543715A
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Alben E Lundell
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AT&T Corp
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Western Electric Co Inc
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q3/00Selecting arrangements

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  • This finvention relates to telephone systems employing mechanical ⁇ switches which are controlled by means of a sending device located at the centra-l station.v
  • This sending device may be operated by an Operator if the system is of the type commonly known as.'
  • semi-automatic or it may be a register sender which is set by the controllingdevice at the calling substation,as in a full auto? Inatic system.
  • the principal feature of this invention re- .sides in having 'at all times. a plurality of connecting vcircuits* preselected or allotted. and a sending with or connected toeach of s'aid preselected circuits.
  • sequence ings may be similar to that disclosed-in Patent No. 1,127,808.
  • the numerals which appear adjacent t0 the. sequence switchcontacts diagrammatically represented'in varie" ous portions of the drawing indicate the positions of the sequence switch latwhi'ch these contacts are closed with the exception that the controlling contacts, oneof rwhich apr pears immediately above the motor magnet ofv each of the sequence switches,jz'areopen only at the positions indicated. by the nu# merals adjacent thereto andtherefore the se-A .j quence switches' can stop in only these position-s. l p 4 braeketsfollowng. the refereeceharaters device definitely ⁇ associated derstanding thereof. 'Y
  • the rotary switchmg devicesshown at ⁇ thef left in Iig.1 1 and at the llower rightcorner in Fig. 2 are allotters'.
  • eachicord circuit is provided at one end with ajline findingswitch l and at ,the other end with a selector 'switch -2, both b ei-ng of the initiation of.' a call by any of the sub'- diately -move to and select the terminals of the callingflineQ vf'lhecalling subscriber will thereupon actuate the sending device at the of my -invensubstation to register the designationor the A line wanted :in a lregister sender which wasI line finder prior to its actuation.
  • the allotter 18 iscaused, uponstarting it into operation. to select a finder switch having its sequence switch in position 16 and' cause the connection of va sender cord finder 29 to the connecting circuit of said cord finder.
  • gT-he allotter went on the contact 22, the sequence switch of which is not in positions 1 to 15.
  • Contact 22 will be vopen and the circuit through mptor magnet 20 will be interrupted.
  • the allotter brushes will therefore stop on the contacts of this connecting circuit. .
  • the brush 23 of the allotter will complete a circuit from ground throughA the lcontact engaged thereby, sequence switch 'contact 12 (16) sequence switch motor magnet 6 to grounded battery,
  • register senders As many register senders are provided as are necessary to handle the maximum number .of simultaneous or substantially simultaneous calls.l 'A register sender is diagrammatically indicated in the dotted rectangle at the left in Fig. 2 of the'drawing. Each register sender is definitely associated with a sender cord finder such as switch 29 in Fig. 2.A A second sender cord finder switch is indicated at the dotted rectangle at the right' in Fig. 2. Associated with the sender cord finder switches isan allotter'v24c, which is similar in function and operation to that in Fig. 1. This allotter determines the order in which. the register senders or rather the register sender cord finders shall be actuated.
  • cord finder the sequence yonly; one line finder lswitchfcan be in position 17 :fat a' time, the contact .'42 of, only one of said 'sequence switches can be open atthis Stime; therefore, as the cord finderA brushes traverse the connecting circuit terminals- ⁇ in .the bank, relay 38 will'be'. maintained energized byl a circuit' through the winding ofl 'said relay, its -ront contact.
  • brush 43 an lcontacts engaged thereby l .to ground throig the sequence switch eo'n- ⁇ Qta'cts 42of all the line finder switches except 'the one which is awaiting the sender. While 5g the cord finder switch brushes are passing right armature thereof, sequence switch contact 44, interruptor 45 and interrupter brush while the cord inder brushes are centrally positioned on the sets' of contacts ofthe ,'-switch bank.' lWhen the brush 4 3 engages the contact associated ⁇ with the waitiiigcom 565. Begging Circuit, -rela'y' 8A will be deenergized,
  • relay '38 is maintainedenergized by a circuitfrom battery through the winding of said relay, front contact and 32. 'This holding'circuit is interrupted only thus interrupting the circuit 'for the clutch magnet 41 and4 stopping the switch. ⁇ At its vback left Contact it will close a circuit froml I batteryathrough ymagnet 26, sequence switch vcontactv 46 (.18) thus driving the cord finder. ⁇
  • Relay ⁇ 52v is energized and locks" up thro-ugh its left armature and normal 'eo'ntact of relay 54. It noline finder sequence Vswitch i's in position 18vat t his time, relay 52 will ree" maiii locked up -until av sequence switch tact 22V (18) conductor- 55, right armature to grounded battery.
  • Relay 54 is thereupon I energized and locks upthrough its left ar-' mature and contact'22;it also closes a circuit from battery through sequence switch moves into'A position '18, when a circuit will be completed through sequence switchv c'on-l Vand contact of relayf52, winding of relay 54 i motor magnet 6, sequence switch contact 12 (18) and right front contact of' relay- 54 to ground and the sequence switch of the subpreselected line finder thereupon goes into position ⁇ 1 -orrst preselected position.
  • sequence switch When the sequence switch goes into position 1 a circuit is completed from battery through allotter' motor'magnet 20, sequence switch,l Acontact 2 2 (l to 15) to ground. The allotter. iswitch is thereupon caused to lselect another finder .switch or connecting circuit, the ⁇ seiis quence switch of .which isf/in position 16,
  • a telephone exchange system a group of lines, a plural-ity yof connecting circuits for use with said lines, automatic switches for connecting said circuits with .said lines, switches for extending said co-n- ,necting circuits to a wanted subscriber, icentral station sending devices for controll.ling lthe operation of said last mentioned iswitches, means for preselectinga plurality of said rst mentioned switches, and automatic means for definitely associating a sen-dingl device with each preselected switch.
  • a telephone exchange system la group of lines, 4,a plurality of connecting circuits, line finder switches in which said connecting circuits terminate, selector switches for extending said connecting circuitsto a wanted suhscribers l-in'e, a plurality of central station sending devices for controlling: lthe i operation of said selector swtitches, means for preselecting a plurality of. said finder switches, and connecting cir- 25 cugit finder switches forl automatically associating a sending device with the connecting circuit of a finder switch when it is preselected.
  • vIn -a telephone exchange system a group of lines, a plurality of connecting circuits, line finder switches in whichsaid circuits terminate, selector switches for-ex tending said connecting circuits to a wanted suhscribers l1ne,"a plurality of central station sending devices for controlling the op- ⁇ 5.
  • a group of lines a plurality of connecting circuits, line finder switchesin 'which said circuitsterminate, selector -switches for extending said-connecting circuitsto a wanted suhscriloers line, a plurality of central station sending devices for controlling the operation vof said selector switches, means for causing a plurality of said line iinder switchesto be preselected,.an allotter assoV eration of said selector switches, means forv causing the preselection of a plurality of said nder switches, an allotter for determining the order of Such preselection, connecting circuit' finder switches for automatically associating a sending device with the connecting circuit of each preselected finder switch, and an allotter associated with said connecting circuit finder switches for determining the 'order in ywhich they shall he operated.

Description

"Af E. LUNDELL. AUTOMATIC TELEPHONE lSYSTEM| 'APPLICATION riLEuMAR. 19, 1915. 4
2 SHEETS-SHEET l. n
a gillllll I Vl5 114 v4 I T l v .VV/Messes: i f l l.//We/wa/x om. me N A/ben Lande/n ALBEN E; LUNDELL, OP NEW YORK, N. y., AssIcfNon, yBY MEsNE ASSIGNMENTS', To WESTERN ELECTRIC COMPANY, INCORPORATED, A cOEPORATIoN OE NEW YORK.
` AUTOMATIC TELEPHONE SYSTEM.
Specification of :Letters Iateirit.v l Patented a11`4-,'19i6.`
Application filed March 19,1915. Seralgo. 15,437.
To all whom t may concern:
Bc it known `that I, ALBEN E. LUNDELL, a citizen of the United States, residing at New York, in the county ofBronX and State oi' -New York, have invented certain new and' useful Improvements in Automatic Telefphone Systems, of which-'the' following is a full, clear, concise, and exact description.l
v This finvention relates to telephone systems employing mechanical `switches which are controlled by means of a sending device located at the centra-l station.v This sending device may be operated by an Operator if the system is of the type commonly known as.'
semi-automatic, or it may be a register sender which is set by the controllingdevice at the calling substation,as in a full auto? Inatic system.
The principal feature of this invention re- .sides in having 'at all times. a plurality of connecting vcircuits* preselected or allotted. and a sending with or connected toeach of s'aid preselected circuits. By means of this invention, Awhen two' calls are answered practically simultaneously, no delay is necessitatedin waiting for the sending device to be associated `with the selected cord circuit.
In the drawings, Figures 1 'and 2,'taken together with Fig. 1 above Fig. 2, represents so much ofthe circuits of-a full automatlc.
system embodying essary for a clear' u ny invention -as isA riec- The automatic switches shown in the 'drawings may be of a structure similar. to
that shown in Patent No. 1,123,696. The sender cord finder switch shown'inF-ig. 2, however, will ordinarily'be provided with but a single set of brushes.
The sequence ings may be similar to that disclosed-in Patent No. 1,127,808. The numerals which appear adjacent t0 the. sequence switchcontacts diagrammatically represented'in varie" ous portions of the drawing indicate the positions of the sequence switch latwhi'ch these contacts are closed with the exception that the controlling contacts, oneof rwhich apr pears immediately above the motor magnet ofv each of the sequence switches,jz'areopen only at the positions indicated. by the nu# merals adjacent thereto andtherefore the se-A .j quence switches' can stop in only these position-s. l p 4 braeketsfollowng. the refereeceharaters device definitely` associated derstanding thereof. 'Y
switches shown 1n thedraw.-`
` switch of the connecting circuit pwill be' in In the sp'eciiica'tionf.thefnumbersl in ofthe sequence switch contacts designate the..
position of the sequence switchat'fthe'time v the circuit `Iexists.
The rotary switchmg devicesshown at` thef left in Iig.1 1 and at the llower rightcorner in Fig. 2 are allotters'. The motor means for.,v
these allotter switches may be similar tofthat.
for the sequence switches. 'The switchshaft,
however, provided with an armcarrying a pa1r,off'brushes instead of the serieso-f disks 'asn-1n the sequence switch. "It is thought that the operation o'these devicesf will be readily understood'y from the followf ing description of the circuits.
In the present embodiment tion eachicord circuit is provided at one end with ajline findingswitch l and at ,the other end with a selector 'switch -2, both b ei-ng of the initiation of.' a call by any of the sub'- diately -move to and select the terminals of the callingflineQ vf'lhecalling subscriber will thereupon actuate the sending device at the of my -invensubstation to register the designationor the A line wanted :in a lregister sender which wasI line finder prior to its actuation.
As the .manner of operation of4 "the preselected Vand definitely associated with the switches forms no part of thepresent inventiOn, we will nowy assume-that the `subscriber `at A has initiated 'a call andsuch Call has been extended through line finder landf selector- 2 and the succeeding switches tol the Wanted subscriber. We will further. assume that the subscribershave inishedtheir con-` versation and disconnection is about to take* place'. During .conversation the sequence position 12.` Upon.` the subscribers. hanging up, the supervisory relays Sand will ybe `deenergized and open the circuit for'relay-5 which in retracting its armature 'willffco'mswitch thereupon moves to position leander the control of 'sequence lswitch contactutg' In'v position 14g a circuit-is GOmPleted sequence switch kcontati-t) for the vvdot'ini-@dlave the switch returns to its normal position. As the-'selector switch approaches normal the interruptor brush engages the conducting segment 11 and completes a circuit from battery through sequence switch motor magnet 6, sequence switch contact 12 (14) contact 11 and brush 10 to ground. The sequence switch thereupon moves't-ofposition 15.
llo
In position 15 a circuitis completed through the sequence switch contact 9, for the down-drive clutch magnet 15 of the finder switch 1. As the finder switch ap- 4@terminals of' lthis. cord finder until its seproaches'its normal position, brush 16 thereof engages the conducting segment 17 and completes a-circuit from battery through sequence., switch motor magnet 6, contact 12 15), segment17 and brush16 to ground. This moves the sequencevswitch to position .16 in which-position it remains until it-.is
preselected by the allotter 18.
At all times -when the system is at rest there are two preselected line finder switches, the sequence, switch of one being in position ,1, the sequence-switch of the other being in posit-ion 1S. Upon the initiation of av call` the finder switch, the sequence switch of whichis in position 1. will be first actuated and the sequence switch of the second pre` lselected finder will immediately' go into po.- f
sition 1 upon the actuation ofthe first. The reason for this and the manner in which it is accomplished will presently appear.
The allotter 18 iscaused, uponstarting it into operation. to select a finder switch having its sequence switch in position 16 and' cause the connection of va sender cord finder 29 to the connecting circuit of said cord finder. gT-he allotter vremains on the contact 22, the sequence switch of which is not in positions 1 to 15. As the contacts individual to the finder switch of the connecting circuit shown in the drawings will be next engaged by the allotter brush and as the sequence switch of' this 'connecting circuit is-in position 16, Contact 22 will be vopen and the circuit through mptor magnet 20 will be interrupted. The allotter brushes will therefore stop on the contacts of this connecting circuit. .The brush 23 of the allotter will complete a circuit from ground throughA the lcontact engaged thereby, sequence switch 'contact 12 (16) sequence switch motor magnet 6 to grounded battery,
Icausing the line finder sequence switch to go to position 17. l
Before continuing the description we will consider the senders and the sender cord finders. As many register senders are provided as are necessary to handle the maximum number .of simultaneous or substantially simultaneous calls.l 'A register sender is diagrammatically indicated in the dotted rectangle at the left in Fig. 2 of the'drawing. Each register sender is definitely associated with a sender cord finder such as switch 29 in Fig. 2.A A second sender cord finder switch is indicated at the dotted rectangle at the right' in Fig. 2. Associated with the sender cord finder switches isan allotter'v24c, which is similar in function and operation to that in Fig. 1. This allotter determines the order in which. the register senders or rather the register sender cord finders shall be actuated. At the time a 'sender finishes yits operation lin 'setting up a connection its cord findervsequence switch will be in position 11.- lVhen the' sender has finished its operation, contact 25 may be closed in any desired manner as by the sequence switch associated with the sender. This rwill complete a circuit from battery through the sender cord finder sequence switch motor magnet- 26` contact 27, (14), contact 25 to ground. The cord finder sequence switch thereupon moves to position 15. In position 15 a circuit is completed from battery, through the down-drive clutch magnet 30 sequence switch contact 31 (15) to ground. The finder switch thereupon returns to normal. As it approaches the normal position, al circuit is completed from battery, through sequence switch motor magnet-,26, seouence switch Contact 34 (15), contact'33 and right spring of brush 32 to ground. The cord finder sequence switch thereupon moves into position 16, in which position it remains until it is seized by the allotter 24.' It may be here noted that the allotter, after seizing the cord finder, re-
lmains on the contact individual thereto until the switch starts into o-peration.
`We will now' assume that the brushes of the allotter 24 are on the contacts individual to the switch 29 indicated at, the right in Fig. 2 and the switch starts into operation. A circuit will'be completed from ground,
` through the-rightspring of' brush 32, contact 36', contact and inner brush of the allotter 241. motor magnet 35, to grounded battery. The allotter will thereupon start into operation and will continue moving as long as its inner ybrush engages contacts indiground, causing the cord 'finderI sequence @switehto moveto positionl?. Witha cord' 'i liii'derv sequence switch `in position 17. when 4to"finder vswitches having'- their se.-
" "fquence'switches in positions1 to 15, a cir.-
cuit fon the motor magnetbeing maintained through the innermost brush, the' contacts if. i5" engaged therebyan'd' sequence 'switch-'coni.' .tacts (.1 to 15) ofthe varius switches,t`o
" ground. If lthe allotter brushes engage `the contacts individual to switch 29, the .circuit through `motor mag-net wili-be--inter- Y rupted at 4contact "37 '.(the'. vsequence 'switch' "".fof'gthis cord finder beingin position 16) the.v allotter will stop. A: circuit will ,nowbe completed-.'from'battery, throughmol "tor :magnet 26,'.to sequence switch contact 37 outermost brush of allotter 24, to
f'jthe; connecting circuit sequence switchlgoes 'i-'ntofposition 17 .which occurred upon the -l-s'eizing of its contacts by the'allotter 18, a circuit is completed from4 battery through 'the rela'y 38,1sequence switch contact 89 (17 41,l 'sequence switch contact 40` (18), front"v contactand left armature of relay 38 tov ,ygroundjjThe' cord -inderA starts .and vas it f-'l'eaves'. it'sfnormalposition its interrupter brushf29. makes `passing contact `with the.
gment 36- and thus starts the allotter'hunt-4 .mgffor another. cord finder the sequence yonly; one line finder lswitchfcan be in position 17 :fat a' time, the contact .'42 of, only one of said 'sequence switches can be open atthis Stime; therefore, as the cord finderA brushes traverse the connecting circuit terminals-` in .the bank, relay 38 will'be'. maintained energized byl a circuit' through the winding ofl 'said relay, its -ront contact. and right armaklture, brush 43 an lcontacts engaged thereby l .to ground throig the sequence switch eo'n- `Qta'cts 42of all the line finder switches except 'the one which is awaiting the sender. While 5g the cord finder switch brushes are passing right armature thereof, sequence switch contact 44, interruptor 45 and interrupter brush while the cord inder brushes are centrally positioned on the sets' of contacts ofthe ,'-switch bank.' lWhen the brush 4 3 engages the contact associated` with the waitiiigcom 565. Begging Circuit, -rela'y' 8A will be deenergized,
sequencefs'witch-'contact 9"'(17) to ground.' A Zlf switch of-.which is in positioi116 -or awaiting allotter position. As the sequence switch of between'terminals, relay '38 is maintainedenergized by a circuitfrom battery through the winding of said relay, front contact and 32. 'This holding'circuit is interrupted only thus interrupting the circuit 'for the clutch magnet 41 and4 stopping the switch. `At its vback left Contact it will close a circuit froml I batteryathrough ymagnet 26, sequence switch vcontactv 46 (.18) thus driving the cord finder.`
sequence'switch into position 1. 'When the brushes of the cord. finder "arrived on' the.vr
.contacts ofthe selected connecting' circuit.
and before the ,cord linder"sequence" switchf movedfto positionl 1, a circuit .was-v com-.
pletedy from battery through motor magneti 6,' sequence, switch contact 47 (17) conduce' tor48, contact and brush 49, sequence switch contact 50 (18)-.to ground.' Theconnecting;l fr
'circuit sequence-switch moves toposition 18"I which is the sub-preselected position and where it remains until the first preselected line finder switch starts into operation. l
Assuming now that Vthe switch diagram- .matically indicated' in the rectangle at ,thel
left in F ig. 1 is started into operation and tion 2, when it leaves Aits normal position the interrupter brush 1.6 makes passing'coiitacti- -with'contacting segment 51', thus complet- 0 ing a. circuit vfrom batterythrough relay 52,'
-that the 'sequence switch thereof is' in posi v 59ans...
sequence switch contact 53"' (2) to ground. y
Relay `52v is energized and locks" up thro-ugh its left armature and normal 'eo'ntact of relay 54. It noline finder sequence Vswitch i's in position 18vat t his time, relay 52 will ree" maiii locked up -until av sequence switch tact 22V (18) conductor- 55, right armature to grounded battery. Relay 54 is thereupon I energized and locks upthrough its left ar-' mature and contact'22;it also closes a circuit from battery through sequence switch moves into'A position '18, when a circuit will be completed through sequence switchv c'on-l Vand contact of relayf52, winding of relay 54 i motor magnet 6, sequence switch contact 12 (18) and right front contact of' relay- 54 to ground and the sequence switch of the subpreselected line finder thereupon goes into position `1 -orrst preselected position.
When the sequence switch goes into position 1 a circuit is completed from battery through allotter' motor'magnet 20, sequence switch,l Acontact 2 2 (l to 15) to ground. The allotter. iswitch is thereupon caused to lselect another finder .switch or connecting circuit, the `seiis quence switch of .which isf/in position 16,
when 'the foregrgng operation. will be're-l pe'ated in connetion with the newly allotted line finder.. What is claimed is':
` '1. In a .telephone exchange system, a
group of. lines, aaplurality of: connectingswitches for extending saidzconnecting cir-A cuits, a plurality of central oitice sending devices orcontrolling said switches, auto-- Vm'atic means for preselectiiig. a plurality of .said connecting' circuits,'f and automatic means forA definitely associating Y a sending 'circuits for use'V with said lines, automatic. 125
device with each of said circuits when it is preselected'.
2. In' ,a telephone exchange system, a group of lines, a plural-ity yof connecting circuits for use with said lines, automatic switches for connecting said circuits with .said lines, switches for extending said co-n- ,necting circuits to a wanted subscriber, icentral station sending devices for controll.ling lthe operation of said last mentioned iswitches, means for preselectinga plurality of said rst mentioned switches, and automatic means for definitely associating a sen-dingl device with each preselected switch. 8. In a telephone exchange system, la group of lines, 4,a plurality of connecting circuits, line finder switches in which said connecting circuits terminate, selector switches for extending said connecting circuitsto a wanted suhscribers l-in'e, a plurality of central station sending devices for controlling: lthe i operation of said selector swtitches, means for preselecting a plurality of. said finder switches, and connecting cir- 25 cugit finder switches forl automatically associating a sending device with the connecting circuit of a finder switch when it is preselected.
4. vIn -a telephone exchange system, a group of lines, a plurality of connecting circuits, line finder switches in whichsaid circuits terminate, selector switches for-ex tending said connecting circuits to a wanted suhscribers l1ne,"a plurality of central station sending devices for controlling the op-` 5. In a telephoneexchange system, a group of lines, a plurality of connecting circuits, line finder switchesin 'which said circuitsterminate, selector -switches for extending said-connecting circuitsto a wanted suhscriloers line, a plurality of central station sending devices for controlling the operation vof said selector switches, means for causing a plurality of said line iinder switchesto be preselected,.an allotter assoV eration of said selector switches, means forv causing the preselection of a plurality of said nder switches, an allotter for determining the order of Such preselection, connecting circuit' finder switches for automatically associating a sending device with the connecting circuit of each preselected finder switch, and an allotter associated with said connecting circuit finder switches for determining the 'order in ywhich they shall he operated.
In witness whereof, I'hereunto subscribe my name this 17th day of March A. D., 1915.
ALBEN E. LUNDELL.
Witnesses i l E. EDLER, I-I. L. STAHL..
US1543715A 1915-03-19 1915-03-19 Automatic telephone system. Expired - Lifetime US1166466A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060080527A1 (en) * 2004-08-27 2006-04-13 Sbc Knowledge Ventures, L.P. Secure inter-process communications

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060080527A1 (en) * 2004-08-27 2006-04-13 Sbc Knowledge Ventures, L.P. Secure inter-process communications

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