US827087A - Harmonic signaling for party-lines. - Google Patents

Description

PATENTED JULY 31, 1906.

W. W. DEAN. HARMONIG SIGNALING FOR PARTY-LINES.

' APPLICATION FILED AUG.9. I905.

03: A dawn 6 0.9% mm}: 5% E i M w w w AW- NITED STATES PATENT OFFICE.

WILLIAM W. DEAN, or ELYRIA, OHIO, ASSIGNOR TO THE DEAN ELECTRIC COMPANY,- OF ELYRIA, OHIO, A CORPORATION OF OHIO.

- HARMQNIO SIGNALING FOR PARTY- -LINES.

I p Specification of Letters Patent.

r mmed July 31. 1906.

Application 518a August 9,1905. Serial No. 273.456.

Toll/ll. wl z om it may concern:

Be it known that LiWI LLLaM W. DEAN, a citizen of the United States, residing at Elyria, in the county of, Lorain and State of Ohio, have invented certain new and useful Im rovements in Harmonic Signaling for Partyines', of which the following is a specifica- -tion, reference Being had therein to the accofipanying drawing.

-r o y invention relates to telephone systems,

and particularly-to What is known as harmomo si aling for arty-lines.

. Accordiiig to metlibds-heretofore employed f ench of several subscribers stations connect- I 5 ed to the same line has been equi ped with a signaling device or ringer adapts to respond to a 'given-frequenc only o si" aling-current. Atthe centrai ofiice seversd generators I have been provided, usually four in number, so since the number of stations on one line in practice is generally limited to that number. .Of course these generators are not usually i built as separate machines, but form parts of onemachine, whose speed is rendered fairly .225 constant by means of govermng devices e whichlit is unnecessary here todescribe. Ac- .J-cordiug to some systems the ringer-armatures .at the substation, which constitute reeds, are.

tuned so as to' belin exact accord with the several i'difl'erent currents'by which they are to be respect velyactuated. Accordihg to other systems the ringers are overtuned or undertuned, according to theird-esign and thejexigencies of the case; but my present invention isnot limited to any of tliese' in articular,'but is, in; fact, applicable to all oftl iem, since its aim is to correct a defeet found in them an; i 7 'In all harmonicpartylinesystems I have 40 found by experiment that while there is race tically no tendency for a current of, big frequency toaffect the bells on the line. which *are tunedto respond to lower frequencies the reverse is not true, currents of low frequenc showinga strong't'endenc' to affect the bel s or. ringers whichlare tune tores ond to high frequencies only. Ihave found 1t possible to overoon 9 this tendency and to effectively limit each ringing-current to its own tuned 5o bell by windmg. generatorsso that th repective outputs shall be of diversevo ages. {find it veryeffective to make a-low-frequency generator of lo'w'voltage and a, highcurrents.

quencybells, which are always har est to ring, can be tuned and adjusted more delifre uency generator'of hi h voltage. It isevi ent that by this method they hi h-fre-v cately than otherwise would be possible without being affected by thelow-frequeney Inorder to still further increase the margin of selection, I als0 find it expedient to makethecondensers of low-frequency bells of larger capacitythan the others, those for the big est-frequency bells being, in fact, of very small capacit My invention is illilstrated' in the accompanying drawing,.which is a diagram of a polystation-line and the central office apparatus .throu h and by which any station on the line can e selected andrun I In the drawing, A, A, A, and A? are sub scribers stationsall connected to :the same pair of line-Wires 1.2. At eachsub'scribers station I provide the usual transmitter T, re ceiver R, switch-hook H, and'whatever other apparatus may be reguired addition t}? the enser ave s own ringer Q and the. con the telephone setandswitch-hook at station A only, their inclusion at 'e'achof the other stations being understood.

At the central office the line-wires terminate, respectively, in the springs j j of the 'jack J, which may be a single hne 'ackiofa simple or transverse boardor may e taken as the type of multiple jacks on a multiple switchboard. In the lattercase'a test+thima ble 7' would be" required for each jackyand I have illustrated it for thatreason. The lin'esignal L is shown as a drop-annunciator, oo'nnected to the line through .cut ofi contaots in the jack, itsv circuit 1920 including a source; of signaling-current B. Y

Cooperating with-the jack and intended to estabhsh connection between the subscribers i p m P, WlJlCh lshere supposedto be the cal mgline and other lines or circuitsfis the.

plug of a pair whose corresponding contacts are connectedtogeth'er throu h cord conduc- I' tors '3. to 11 and 4 to'12.- I H ve shown the plugl with a ta -contact pconnected to the twm or answering. plugofithev pair. my

conductor 3 an the sleeve-contact con- -nected' to theconductor 4. The con uctors a 11 and 12are therefore supposed to besimilarly connected. to the. tap and'sleeve' of thel nd G, "and there the caliing illustrated". rovide four selective ringing: e h s. t wh at any partlcu ar one of the four stations A 1N4 At Each of these l ingvkcys has a r of s m 8 with front-a H back. ntacts. hse o, the y K are 1r and n th ir no mal condition of dream they rest upon th i ont contacts connected o th ndu t r 5 and 6, wluchpass then e to the snlicgsk. and-k of the key K these in turn normally resting, upon front 300M100 ,can-

nested. thfo -Wes 7 and 8 to the springs it-26m e -oft keyK, whlch not-really rests scc sntacts diss cted tbrou hwircs 9 and ze m si k d s" its s e! rest a ts-c t see-springs 1 tc'th conductors ll and 12. E

' eys is pr vided with an actuatingbntton or layer with-a cam, which upon actuation of. the I 'cles, I double the capacity,

button or. level B ts to spread apart the -springs, breaking. the commotion between per second.

conductors 3 .4 and 11 "12 and establishing a conncctlon f om the conductors .3 4 to onc'of the generators. Thus u on actuating the. button orlever' of key K t e springs k and k" are carried'from the terminals of wires 5 and Q close the circuit for generator G, which may be traced as follows: on the one ide from the I generator (3; and bg wires '17 and 18 to e other side from the sleeve 12 through con- 1'. ln'ctor 4 to the spring k and thence direct to the ground- The Iilu having been inserted the J J en t e ey K is thus actuated, current from the generator G will pass out from the line-wires 1 2 to actuate the ball at he corresponding station.

The ringers Q, Q, Q, and Q? at the sta- A N, respectively, are designed to respond to and be actuated by currents of the following frequencies: for ringer Q, can

rent at 66.6 -cycles; for ringer-Q, current at 'fiftycycles; fcrnngcr Q,currcnt at 33.3 cy-- cles, andfor ringer Q current at 16.6 cycles G are wound and rents of the four. that is, gsneratorizragives current at 66.6 cycles, G current at ty cyclcafil current at 33.3 cycles-and G? current at 16.6; cycles.-

There is nothing essentially novel in the sfistem.thue far described; With. some s ght modifications it might be taken as a type of that class of systems familiar to telephone engineers under the name of f run so as to. produce. curconnected sell of the this one-fourth of a nucrofarad. The rlfrilfgter Q tip 12 through conductor 3 to the springk, thence to the.

the ground at g; on.

'scri tion that t since I have cut down the generators .G, "G', G?

frequencies mentioned-;

however, may now be understood and will be described as ap liedtopthe foregoing, It

con' sts essent aly 1ng1 the generators Gr, El, and G3 $1 101! 'pecu a w sdi a-srbo h the they w produce theirrespective current at diverse Voltages ae'wsll as of diverse frequencies. Thus' the "generator-G, Idesign to produce current ata Voltage ofitwo hundred, generator G at one hundred and fifty, generator 43: at one hundred and the high-freqncncy generators also high voltsfif machines, .relatiyely speaking and the w frsquency generators I {no a low-voltage machinos. 0011351101111 1 1% m ysind the nngers Q Q Q Q of (ii crent resistance, or, as I have shown m the I preferably make the condenser's in t e ringer branches of diverse copacitie's. The ringer Q at station'A being tuned respond to current at a'frequency of 66.6 cycles per second, which is the marrimnm employed in the system, I include 1n ringerbranch the'rninimum canacity of being tuned to respond to current at ycymakmg it oneiarities of speed halfof a mierofarad. For ringer Q, I again double'the capacity, making it one micrsfared, and for ringer Q Iprovide two microfarads. The condensers 0, .C, .0, and .0 have progressivslyiucreasing capacitics therefore, the largest capacity .0 corresponding to the lowest quency and the lowest-voltage current which is thrown out by the generator (3?. nregolng'de- It Will be apfiarcnt from the are will be little or no chance for eakagc and consequent-interference by low-fro uency current through the high-fro.-

quency ranches at stationsAA. The h frequency bells are the hardest to or mechanical as well as electrical reasons, and capacity a smallfraction and the voltage-or pressure of the current also to a small fraction of the maximum, the freiuency being already a small fraction thereo the amount of leakage transmitted through; the highefre negligible. Moreover, it wi' be noticedm going down the scale from station to station as the capacities and voltages increase th tendency to interference decreases; 'llhns the system is perfectl symmetrical. I believe I am the first-person to combine thafactors by which ener transmission has heretofore beanseparate -l. imite.cl. -1 Ishall thereficre-claim the" same (madly and wish it .to be distinctly nnderstoodthat all applica tions of'this broad idea; whatever be their specific form, and all the mod fications which may be made-therein arc contemplated'by as. withinthescope and purview of my invention.

ncy branch is.

' rent impu ses to any desired frequency at a voltage approximately proportionateto the I said signal-receiving devices being tuned to ringers connected thereto, a corresponding scribers line and a plurality of differentlysponding plurality of ringing-generators at one of said generators being adapted to fur nish current of low frequency and at arela- Having thus described my invention, What I claim, and desire to obtain by Letters Iatent, is

1. In a telephone system, the combination of a plurality of signal-receiving devices tuned to respond to periodic impulses at different fre uencies', and means to supply curfrequency.

2. In a telephone system, the'combination of a line-circuit and a plurality of signal-receiving devices connected thereto each of respond to a current of a particular frel quency, with sources of current, and means to connect one or more of said sources to said circuit, the current from said sources varying not only as to its frequency but as to itsvoltage.

3. In a telephone-exchange system, a party-line and aplurality of diflerently-tuned plurality of periodic current-generators, each furnishing current of a given frequency and at a voltage approximately proportional to the frequency.

4. In a-telephone-exchange system, a subtuned ringers connected thereto, a correthe centr station, adapted to furnish ringing-currents of high and low frequencies, and of high and low voltages, and switching means whereby any oneof said generators may be connected to said line.

5. In a telephone-exchange system, a subscribers circuit and a plurality of stations connected thereto, a ringer at, each station connected to the circuit and tuned to respond either t9 giigh or low frequency currents only, central-o ce switching means and a plurality of selective ringing-generators adapted to be connected thereby to the subscribers circuit,

tively low voltage, and another of said generators beingadaptedto furnish current of high frequency and at a relatively high voltage, whereby the low-frequency current will be unable to objectionably affect the highfrequency ringers.

6. In a telephone-exchange system, a party-line with a plurality ,of subscribers ringers connected thereto, said rihgers being rality of sources of ringing-current of progressively-increasing frequencies correspondmg to those of the ringers, and means to pre- 'vent current of one frequency from passing pitch, a plurality of generators adapted to' furnish ringing-currents ranging from high to low in frequency, and means to regulate the output of the generators according to their frequencies by limiting the effective electromotive force impressed on the line thereby.

9. In a telephone-exchange system, a plurality of tuned bells,ranging from high ,to low pitch, a plurality of generators adapted to furnish ringing-currents ranging from high to low' in frequency, and means for regulating the amount of effective current from any one generator which shall pass through each ringer by limiting the effective electromotive force impressed on the line thereby.

. 10. In a telephone-exchange system, a subscribers line and a plurality of harmonic ringers connected thereto,- means for furnishing selective current for said ringers, a condenser in circuit with each ringer, the capacities of the condensers being inversely proportionate to the frequency to whichtheir corresponding ringers are tuned and means to limit the output of current for each ringer by limiting the effective electromotive force at the ringer terminals.

-11. In a telephone-exchange system, a

party-line and a' plurality of subscribers stations having ringers tuned to progressivelyincreasing frequencies connected to said li'ne,

central-office switching apparatus for said line, and a pluralityof ringing-generators furnishing current of progressively-increasing frequencies at progressively-increasing voltages.

In testimony whereof I affix my signature in presence of two Witnesses.

WILLIAM w. DEAN. Witnesses A. D. THIBBY,

Gno. A. SoovrLLE.

Images