USRE17632E - nelson - Google Patents

nelson Download PDF

Info

Publication number: USRE17632E
Authority: US; United States
Prior art keywords: relay; circuit; digit; switch; conductor
Prior art date: 1921-02-09
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.): Expired

Application number

Other languages

Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)

1921-02-09

Publication date

1930-04-01

1930-04-01 Application granted granted Critical

1930-04-01 Publication of USRE17632E publication Critical patent/USRE17632E/en

Status Expired legal-status Critical Current

Images

Classifications

- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q3/00—Selecting arrangements
- H04Q3/42—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker

Definitions

the present invention relates to "multiofiicetelephonesystems, .more especially to such systems as comprise both manual and automatic .o'ifices, or exchanges; and the object of'the' invention, broadly stated, istne provision V of 'n'ew and; improved arrange- 'm*ents"for handling those calls which orig- -i 1rate at-a manualofli'ce and which are completedin an automatic office.
An' essential feature of the invention is the B operat'ors" sending equipment at the 'automatic"exchange.
This apparatus includes" a'novel sending switch, and a plu- 'rality"of"rel ay storagedevi'ces, of newfde "sign, *tog ether with circuits whereby the digits, corresponding to successively act-uated digit' keys, are registered on the storage devices, whereby the storage devices .successively co'ntrol .th es'ending switch according to theregistereddigits, and whereby the entire apparatus I is automatically d'isassociatedjfrtm the trunk linein use when the connection-is compl'eted.
a'novel sending switch and a plu- 'rality"of"rel ay storagedevi'ces, of newfde "sign, *tog ether with circuits whereby the digits, corresponding to successively act-uated digit' keys, are registered on the storage
connection when established, involves a manual cord circuit such as the cord circuit 0, Fig. 1; an iIiter-oifice trunk line, manual to automatic, and associated trunk equipment, shoWn in Fig. 2; a first selector switch D,Fig. 3; a second selector switch such as the second selector E; and a final connector switch such as the connector H, Fig. 4.
the apparatus 'shown'in Figs. 5, 6, and 7 constitutes a' B dperators sender which is used 'to control the setting of the automatic switches, "and'which may be temporarily associated with the trunk line for this purpose.
Fig, 8 shows a lamp indicating device associated with the sender shown in Figs. 5, 6, and 7. l
the equipment shown in Fig, 1 comprising the telephone station A and the associated line e'quipm'ent at the exchange, the operators cord circuit 0, and the A operators head set, is all manual equipment of well known type and on this account will not have to be described.
the inter-office trunk line comprising conductors 'and 3 1, is one of a large group of similar trunk 'lines and extends from the jack'Jin the outgoing trunk multiple at the Aboard, in' the manual exchange, by way of the B opera'to'rs position, shown in Fig. 2 to the first selector D, which is shown in Fig.3.
the trunk'line is normally open and is provided with a group of relays, whose circuits are sho'wnin full, and whose operation will' also be described'in the course of the general.
the connector switch H has. access to 100 subscribers lines, one of which is the line extending to automatic. sub station A.
the reference character C indicates a rotary line switch of well known type which isindividual to the line of substation A and which is used by the subscriber thereat for making outgoing calls.
the digit keys Noel to 0, inclusive are ordinary self restoring keys, or push'buttons, located in'a single row in front ofthe B operator, and control thesetting of the storage devices. There is also a release key? R and a'lamp L*- located in" the samerow with the digit keys.
the sending switch S in Fig. 5, is a simple rotary switch having two horizontal rows of bank contacts and the two wipers 207and 208 associated therewith. These wipers are adapted to be driven by any suitable form of ratchet mechanism ina forward direction only by means of the stepping magnet 206.
the cam 298 is mounted on a constantly rotating shaft which is driven by a small motor, or other suitable means, at a speed of about ten revolutions per second. This is the impulse sending cam and may be common to a number of. difierent senders.
the first digit storage device shown in Fig. 6, comprises the digit relays 271-270, inclusive, and, the five relays 250-254, inclusive.
the other storage devices are very similar to thefirst digit storage device, and all of themv will be described in full hereinafter.
any sender may be connected with any inter-oflice trunk line.
the local trunk line associated with the sender shown in the drawings comprises conductors 221-224, inclusive, which conductors are connected in multiple to contacts of relays, such as the relay v45, associated with the several inter-oflice trunklines.
the local trunk line associated with the second sender is shown in the drawing at the right of Fig. 2, and comprises conductors 221 to 22 i, inclusive.
the local trunklines associated with the other twosenders are similar to the one shown and, therefore, it
Thelamp indicating device shown inFig. 8, is individual to the sender illustrated, and there is a similar indicating device for each of the other senders.
This indicatingdevice comprises a plurality of banks of switch-board lamps, there being a lamp in each bank for each of theten digits.
the number of. different banks, of lamps will, of course, depend upon the number of digits in the telephone numbers; for four digit numbers four banksof lamps will, of course, be required as illustrated in the drawing.
the digits to which the lamps correspond are printed on a semi-transparent screen behind which the lamps are located, and these numbers are ordinarily scarcely discernible. When the lamps immediately. behind any seriesof. digits are lighted, however, these vof the several storage devices.
the lamps immediately. behind any seriesof. digits are lighted, however, these vof the several storage devices.
the sleeve conductor thereof which" includesthe, cutofimelay 5 of the calling. line,- andthe supervisory lamp L, in
Thesupervisory lamp L would rbe. liglrtednt, thesame time were it not: forjthefacti thatgthe receiver is off at sub: station A, whose transmitter is nowsupplied 'with: current from the cord circuit.- As iaeresult, the supervisory relay 8-in theringside ,of the cord circuit is. energizedand.:shunts .out the lamp L. to prevent it from being lighted;
the A operator willnow. throwher key, K. to listening position in order to obtain.
theB operator will; depress; the digit'keys 4, 5,6, and 7 in.rapidqsuccession andn-the entire number is completely registered practically as soon as the A operator. has finished transmitting it.
the ASOPQIEltOIlS throughtalking the B oper; ator will reply with the numberct an idle interoiiice trunk line.
the Aoperater now inserts the calling plug of the cord circuit in use in the designated jack in the outgoing trunkgmultiple Assuming that thetrunk linescomprising; conductors and 81 is the ,3 trunk; line assigned,- the plug -will be in: sorted in the jack- Jand a circuit issim mediately completed rover the tWo sides-of thetrunkline in ser-ies for the bridged rev lay 4O at-theB operators positioin Relay 40. is. energized.by current flowing -t'rom the cordcircuit at the A board andcloses a circuit forthebusy lamp L hisnotifies the B2; operator that the-A; operator; has
Fig. 5 is now operated. under the control oi. the several storage devices in succession and four series oiimpulses' are .transmitte dover the trunk line comprising.conductorsBO and 6 1, gconnnecting Figs. 2 and 8, whereby.tl1e, first; selector-D, a secondselector, such as. the selector E, and aconnector, suchas the connector H, are o'peratedinorderto. complete connection to thedesired subscribers line.
the .B operator hayingactuated thetrunk, keyg K, has done all that is required of her. toward the establishment of .the connection and;need pay no further attention. to it.
The-sender upon which the number has been registered, controlsv the automatic. switches. without any further attention and when the last switch .has :beenoperated the sender is automatically disassocia ted, from the. trunk line and. is. ready. for use. in registering anotherflcalled numberu
Theten digit relays of the ⁇ . first digit. storagedevice are normally-cons,
relay 27 i prepares a lockingcireu'it it'or, itself *at armature281 connectsvthe ground ed conduct-or. 228 .to conducton284.which. ex tends to. the .No., 45131111) .in Q the first. digit bank of the lamp, indicating device, and causes the digit; 4 to be, immediatelyv dis-. played; and. connectsthe grounded, conduc tor 288 with the conductor 26 4 which extends the digit keys.
relay 274 "is held up over the hereinbe fore mentionedlocking circuit which in-* eludes relay 252 andthe grounded conductor 226.
Relay is accordln 'ly energized 111 series with relay 274, having been prevented from energizing before by the short-circuit- Relay 252 also connectsground'to the holding conductor 223 at armature 260, and at armature 259 connects ground to conductor 285 extending to the'second digit storage device, Fig. 7, thus completing a circuit for relays 304 and 305 in series.
these relays connect the ten digit relays 321 to 320, inclusive, to the ten conductors coming from the digit keys. In this manner the second digit storage device is prepared for registering the second digit.
relay 3 25 prepares a locking ClICUlt for itself at its armature 331, connects the grounded conductor 228 to the lamp conductor 335 at armature 333, thereby dis-' playing the No. 5 digit in the second digit bank of the lamp indicating device, and con nects conductor 388 to conductor 265 at armature 332; The latter conductor extends to the lower bank of the sending switch Sand terminates there in bank contact 295.
Relay 303 also grounds the holding conductor 223 at its armature 3'11, and at itsarmature 310 groundsthe conductor 385 which extends to the third digit storage device, thereby completing a circuit for the relays, corresponding to relays 304 and 305, which connect the ten digit relays of the third digitstorage device with the conductors coming from the digit keys.
a key' may be inserted in thebattery conductor in order-to disconnect the current supply from the lamps',-and the key may then be operated-whenever itis desired tOyShOW upsome particular number.-- In case an inspection-of theindicatingwdevice should show that a telephone number has been registered inaccurately, the release key R may be actuated in order to energize relay 203"for the purpose ofrestoringjthe digit relaiys of the-several storage devices-to norma position.
Gonductors 221 and 222 are normally 1 connected together at armature 212 and also at armature 214 of relays 201and 202 of the sending switch S, and it follows, therefore, that a circuitis completed over the trunk conductors 60 and 61 for the line relay 65 of the first selector D, Fig. 3.
relay 65 closes a circuit for the slow acting-release relay :66.
the latter relay upon energizing, opens a point in the circuit of the release magnet 72 and prepares a circuit for the vertical magnet 7 0 in the customary manner. 7 7
Relay 44 is operated when the circuit is closed through its upper winding and completes a locking circuit for itself at its armature 48. Inadditionrelay 44 closes apair of contacts in the trunk conductors in'order that when the relay 45 deenergizes, as will occur shortly, the said trunk'line may extend continuously through the operators position.- hen relay 45- is energized, as
the conductor 224 is grounded, being connected witlrconductor 223 at armature 52, and a circuit is completed for slow acting relay 204, Fig, '5;
relay204 closes a circuit for slow acting relay 205 atits armature217 and at its armature 218 disconnects ground from the conductor 228.
the latteroperation extinguishes the lights in the lampindicating device, and when the slow acting relay 205 pulls up it opens the normal ground connection to conductor226 at its armature 219 and substitutes therefor a ground coming from the working contact of armature 218 of relay 204.
armature 212 the shunt circuit which nor mally renders the impulsingrelay 202 ineffective to interrupt the circuit of the line relay of the selector D.
the impulsing relay 202 continues to be energized and deenergized intermittently bythe operation of the cam 298, andat each energization this relay will separate the two conductors 221 and 222 and will thereby produce a series of interruptionsin the circuit of the line relay of the selector D.
relay 202 transmits a series of impulses to the stepping magnet 206 at armature 215, and the sending switch S is thus driven synchronously with the first selector.
Relay 200 also closes a new circuit for the stepping magnet 206 at armature 209, and since this circuit'includes an interrupter contact controlled by the stepping magnet itself, the said stepping" magnet will operate in the manner of a buzzer and the switch will be advanced automatically until wiper 207 arrives at the first ungrounded contact in its" bank which, as shown in the drawing, is the twelfth bank contact.
Relay 250 is, therefore, energized with, the result:
the slow act ing relay 200 also deenergizes after a brief instant and at its armature 211 again closes the circuit of the. impulsing relay 202.
This relay now beginsoperating as before and on its first energization' transmits an impulse of current to the stepping magnet 206 without, however, interrupting the-switch control circuit over the: trunk line, which now ex tends through to the secondselector "On the first step of the sendingflswitoh S, wiper .207 arrives at then-thirteenth bank contact' and since this contact is grounded a'circuit i:'
Relay 301 is accordingly energized and at its armature 306 disconnects conductor 287 from the windingof relay 302 and transfers it by Way of conductor 387 to a similar relay in the third digit storage device.
relay 301 disconnects the grounded conductor 286*from conductor 388, therebyre moving ground from the bank contact 295 in the bank of the sending switch S, and
the connector H responds tothe third series of impulses, and its'shaft and wipers are raised five steps until they stand oppoite the fifth level of bank contacts. No: automatic movement takes place at the connector, however, upon the cessation of the series of impulses and further movement of the connector is deferred until the arrival of the next series of impulses.
wiper 207 When the wipers ofthe sendingswitch S arrive at the twelfth set of bank contacts, wiper 207 will find. no ground and relays 201 and 200 are accordingly deenergizedto again start the operation of the switch; The impulsing relay 202 now begins to step the switch S around as before, and after the said conductor and conductors 287 and. 387
the operators sending equipment including the four digit storagedevices and the sending switch S, is thus entirely restored to normal position and is ready for use again in regis tering another telephone number.
this relay remains locked up to'thegrounded conductor 56 at its armature 48.
the incoming coni ductors 30 and 310i the inter-oflice trunk line. are connected through the two condensersby Way ofarmatures 47 and 49 of relay 44, andthrough the normally closed sets of contact springs controlled by'relays' 45 and 46 to the outgoing trunk conductors and 61, which "have-been extended by the operation of selectors D andE and theconnector H,fto the desired called line; It will be observed that there is a bridgeacross the trunk.
the control circuit of the first selector D includes sending switch S, and the trunk conductors 60 and 61, and when the first series of interruptions is produced in this circuit by the intermittent impulsing relay 202 of the said sending switch, the line relay 65 of the first selector is caused to retract its armature a corresponding plurality of times.
relay 65 sends a current impulse through the slow acting series relay 67 and the vertical magnet 70 in series, and the vertical magnet is oper ated to raise the switch shaft step by step until the wipers 80, 81, and 82 stand opposite the fourth level of bank contacts- Relay 67 is energized in series with the vertical magnet, and being slow acting retains its armature in operated position throughout the vertical movement of the switch.
the off normal springs 78 are closed and since relay 67 is in operated position a circuit is completed for the stepping relay 68.
relay 68 Upon energizing, relay 68 establishes a locking circuit for itself at its, upper armature,.and at its lower armature prepares a circuit for the rotary magnet 71.
the slow acting relay 67 is deenergized and closes the circuit of the rotary magnet 71 which accordingly operates to rotate the switch shaft one step and brings the switch wipers into engagement with the first set of bank contacts inthe fourth level.
the rotary magnet opens its interrupter contact and thus breaks the locking circuit of the stepping relay 68, which accordingly deenergizes and breaks the, circuit of the rotary magnet whichther'eupon deenergizes also and again closes its interrupter contact.
trunk conductors 60 and 61 have beenv extendedt'hroughto the" second selector E have occurred in response to" the transmissi'oni ofth'e first series of' impulses by the sending" switch" s;
the-linere'l'ay 90 of the second selector E is deener-* gfized a lurality oftimesand controls the vertical magnet 92 to raise the shaft and wipers 100 102, inclusive, tothe fifth level, the second digit in the number being the digit 5, as explainedheretofore.
The-operation of the second selector E' is precisely the same as that of the first selector'D, and consequently it willjbe unnecessary to consider it in detail.
the switching relay 99 at the second selector E is connected to the holding circuit the same" as was described in the case otthe switching-relay 69* of the first selector.
the line relay 111 of'the connector H is 1110- inentarily deenergized six times and at each deenergiz'ation transmits an impulse of current to the vertical magnet 118- over path whichextends from'groun'dby way of armature-124C and its resting contact, armatare- 126 and its working contact,- oftnorma l springs 121 and 123, winding ,otthe slowacting series relay 113, and: the winding of 'the-vertical magnet 118 tobattery.
Relay 113 is energized in series with the vertical magnet 118 and being-slow acting holds up continuously during thevertical operation of the switch. By the operationxof this relay, the vertical magnet. circuit is preserved intact, notwithstanding the shifting of the off normal springs, which occurs at the first vertical step oflthe switch. At the end of the vertical movement, relay 113 deenergizes and transfers the operatingcircuit to the rotary magnet 119.
the last series of impulses comprises seven:
the wipers 150-152, inclusive are rotated step bystep and are finally brought to rest in engagement with the particular set of bank contacts in whichthe line of sub- I station, A is terminated, thesecontacts being indicated in the drawings by reference characters 153, 154 and 155.
the slowacting relay 116 is energized in parallel with the I rotary magnet and remains continuously en-.
relay 116 connects the test wiper 151 to the winding of the test relay 115 by meansof its armature 133 and at armature 135 closes an alternative point in the circuit of the rotary magnet, to guard against the possibility of having this circuit opened by the operation of the test relay while the test wiper 151 is passing over grounded test contacts.
v I i The final series of impulses has now been received, and the connector wipers have been,
test contact 154 If the-line is busy there will be a ground potential on the test contact 154 and the test relay 115 will be energized.
this relay When this relay operates it prepares a locking circuit for itself at its armature 131, which is completed when the slow acting re lay 116 falls backan instant later, opens the rotary magnet circuit at armature. 132, and
a signalling circuit is established whereby ringing current from the generator GEN is intermittently projected out over the called line to operate the bridged ringer at substationlA and notify the called subscriber that heis wanted.
the return path for theringingcurrent includes the upper winding of the ring out off relay 114,.and
relay 114 Upon energizing, relay 114-establishes a locking circuit for itself at its armature 129, breaks the ringing circuit at armatures 128 and 130, and at the working contacts ofthese same armatures pletes the talking connection.
This relay is a reversing relay and has the well known funcfinally com-' mass tion of reversing the incoming trunk conductors 106 and 108 asregar-ds their connections with the windings of the line relay 111.
Relay 40 remains energized, owing to the fact that its lower winding is still connected in the bridge across conductors 30 and 31-, and the result of shunting out the upper high resistance winding of this relay is to augment the flow of current sufliciently'to operate the supervisory relay 7 at the operators cord circuit in the manual exchange. This serves to extinguish the supervisorylamp L and notifies the operator that the called subscriber in the automatic. exchange has answered his telephone. The subscribers may now converse as desired;
deenergizing, relay 44 opens the trunk line at armatures 47 and 49, thereby clearing the bridge across the trunk conductors 60 and 61'.
the line and release relays 111 and 112 of the connector H are permitted to fall back and these relays jointly close a circuit for the release magnet 120, whereby the connector is restored to normal in the usual manner.
Relay 11 2' also rcm'ovesground .from the release-trunk conductor .107 and this operation breaks. the holding circuit for the switching relays 69 and 99 of the selectors D and E, respectively.
These relays are, therefore, deenergiz'ed and circuits are completed for release magnets 72 and. 93 which operate to restore their associated switches to normal position. All the apparatus is thus returned to normal and is ready for use in setting up other connections.
a and B operators positions trunk lines coming from the A operators position and passing through the B operators position to automatic switches, other automatic switches, means for manually connecting a calling line with one of said trunk lines at the A operators position, an operators sender at the B position comprising a progressively movable sending switch and a plurality of storage devices, said sending switch including a contact dc vice, means whereby the B operator can register the digits in the number of the called line on said devices, means for connecting the sender with the trunkjline in use, means whereby the sending switch is then controlled by said storage devices successively to transmit series of impulsesover the trunk conductors by means or said contact device to operate a series of said switches to connec't with the called line, and means for automatically disconnecting the sender when the connection is completed.
a and B operators positions, trunk lines coming from the A operators position and passing through the B o'perators position to automaticswitches, other automatic switches, a call circuit x tendin between said positions whereby the A operator can transmit a desired called number to the B operator, an operatorssender at the B position comprising a progressively movable sending switch and a plurality of storage devices, said sending for'connecting a calling line with 'a particular one ofsaid trunk lines assigned by the B operator over sald call circult, means whereby the B operator can connect said of digit keys sender with the trunk line assigned, and means for then automatically operating said sending switch under the control of said storage devices to, transmit a plurality of series of 'impulses'over the trunk conductors, bymeans of said interrupter to operate a series of said switches to complete the, connection to the calledlinea a v i 3.
a set ofdigit keys one for eachdigit, a plurality of storage devices each comprising a set of digit relays, one relay for each digit, means whereby the successive actuation of a plurality causes the energization of a particular digit relay in each of said storage devices, an impulse sending mechanism, and means for'placing said mechanism-- under control of said storage devices successively.
a set of digitkeys a plurality of storage devices each comprising a set of digit relays, the digit relays of the first device being normally connected with saidkeys, and transfer relays andcircuits effective to disconnect the digit relays of one device from said keys and to condevice tothenext, means for energizing the corresponding digit relayin one of said devices when any digit key is actuated, and
a plurality of storage devices each comprising a set of digit relays, acommon set of digit keys, a transfer relayin each storage device nfor shifting the control of said keysfrom one storage device to the next, means for energizing a digit relay in" one of sald devices when a digit key is actuat-' ed, and means for energizing the transfer relay in said device inseries with the energized,
a transfer relay in each storage devicefor shiftingvthe con trol of said keystfrom one storagedevice to the next, means for energizing a digit relay in one of said devices when a digit keyis actuated, a self locking circuit: for the ener gized digit relay including the associated transfer relay, and-circuit connections such that current flow through said transfer relay is delayed until the actuated digit key is restored.
a switch control'circuit In an operators senderforzcontrolling automatic switches, a switch control'circuit, a step, by step switch, a constantlydriven interrupter, a relay intermittently energized by'said interrupter, contacts'on said relayfor interrupting said control circuit and other contacts on said relay for sending impulses of current to said, switch, and means for preventing saidcontacts from interrupting said control circuit before an effectivev impulse is sent to said switch by saidother contacts: I i v I 10
a switch control-circuit, a step by step switch, a relaygand'means for closing an intermittent ,fenergiz ing"circuit therefor contacts on said relayfor interrupting said control circuit, contacts-on said relay for sending operating impulses to said switch, and circuit connections for-prevent ing the, saidcontrol circuit from; being'interrupted until said switch has befenmoved a definite distance.
a i switch control circuit for controlling automatic switches, a i switch control circuit, ma-step 'by ste 'switeh, a relay'- an'(l uneans for i'elesi'n g :an intermittent energizing circuit therefor, contacts on said melay lor *int'ergqomupting said control circuit, contacts on nelay i'or sending o'pei ati'n'g impulses ato-sai'dsswiitch ,1means 'controlled in -the movennent rof said switch qfor openin-g tlie enercircuitrof said l-l'elay afiter a 'tlel'in'ite aeenies 2'1 of iinterruptions has heen :produced, aan'daa cimuitiiferautomatically: driving said swith to a manual j:position independent o'f w
alnmnnpemtnrls sen'der fo'r. controlling untomtic-swv'itches, ;a switch control reireuit, aaatcp bgyshstepz sw-itch, :a relay :and means for closing an intermittent :energizing circuit '50 rthemior, icentacts rfllli fifid d relay for interrl itlitingisaidrcwnbroli circuit; contacts "on :said
V 19.1n a "telephone system, automatic 5 switches "for connecting a calling and called line, an operators sender for controlling "said switches and comprising operator controlled registering devices for registering the digits in the number of the called line, key s common to-said devices for-setting them successively, a 1 number indicator comprising groups-of lamps, -an'd means for -lig'hting the roper lamps to display the registered numrer to the operator.

Landscapes

Engineering & Computer Science (AREA)
Computer Networks & Wireless Communication (AREA)
Structure Of Telephone Exchanges (AREA)
Sub-Exchange Stations And Push- Button Telephones (AREA)

US17632D 1921-02-09 nelson Expired USRE17632E (en)

Applications Claiming Priority (1)

Application Number	Priority Date	Filing Date	Title
US175260XA	1921-02-09	1921-02-09

Publications (1)

Publication Number	Publication Date
USRE17632E true USRE17632E (en)	1930-04-01

Family

ID=21783092

Family Applications (3)

Application Number	Title	Filing Date
US1615998D Expired - Lifetime US1615998A (en)	1921-02-09	nelson
US1614678D Expired - Lifetime US1614678A (en)	1921-02-09	nelson
US17632D Expired USRE17632E (en)	1921-02-09	nelson

Family Applications Before (2)

Application Number	Title	Priority Date	Filing Date
US1615998D Expired - Lifetime US1615998A (en)	1921-02-09		nelson
US1614678D Expired - Lifetime US1614678A (en)	1921-02-09		nelson

Country Status (3)

Country	Link
US (3)	USRE17632E (da)
FR (2)	FR543550A (da)
GB (1)	GB175260A (da)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
US2749535A (en) *	1951-11-23	1956-06-05	Westinghouse Electric Corp	Telemetering systems

0
- US US1615998D patent/US1615998A/en not_active Expired - Lifetime
- US US1614678D patent/US1614678A/en not_active Expired - Lifetime
- US US17632D patent/USRE17632E/en not_active Expired
- FR FR26655D patent/FR26655E/fr active Active
1921
- 1921-11-14 FR FR543550D patent/FR543550A/fr not_active Expired
1922
- 1922-01-24 GB GB2145/22A patent/GB175260A/en not_active Expired

Also Published As

Publication number	Publication date
FR543550A (fr)	1922-09-05
US1615998A (en)	1927-02-01
GB175260A (en)	1923-04-12
FR26655E (da)
US1614678A (en)	1927-01-18

Publication	Publication Date	Title
US1930525A (en)	1933-10-17	Signaling system
USRE17632E (en)	1930-04-01	nelson
US1870997A (en)	1932-08-09	Printing telegraph exchange system
US2187186A (en)	1940-01-16	Telephone system
US1910867A (en)	1933-05-23	Automatic concentration system
US1916760A (en)	1933-07-04	Telephone exchange system
US2227121A (en)	1940-12-31	Printing telegraph system
US2381516A (en)	1945-08-07	Relay type key sender
US2065894A (en)	1936-12-29	Telephone system
US1449644A (en)	1923-03-27	Telephone system
US1078229A (en)	1913-11-11	Signaling system.
US1364909A (en)	1921-01-11	Telephone system
US1312702A (en)	1919-08-12	martin
US1576884A (en)	1926-03-16	Telephone system
US1387284A (en)	1921-08-09	Telephone system
US1393352A (en)	1921-10-11	Telephone system
US1190185A (en)	1916-07-04	Automatic telephone system.
US1711744A (en)	1929-05-07	Telephone system
US1512907A (en)	1924-10-28	Assig-nor to western electric com
US1553337A (en)	1925-09-15	Telephone-exchange system
US1501287A (en)	1924-07-15	Automatic telephone system
US1324202A (en)	1919-12-09	martin
US1484933A (en)	1924-02-26	Telephone system
US1438744A (en)	1922-12-12	Telephone-exchange system
US1523998A (en)	1925-01-20	Telephone system