US820064A - Selective telephone. - Google Patents

Selective telephone. Download PDF

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US820064A
US820064A US23827604A US1904238276A US820064A US 820064 A US820064 A US 820064A US 23827604 A US23827604 A US 23827604A US 1904238276 A US1904238276 A US 1904238276A US 820064 A US820064 A US 820064A
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wire
tho
line
magnets
circuit
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Noble S Mckinsey
Anton R Nelson
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/68Circuit arrangements for preventing eavesdropping
    • H04M1/70Lock-out or secrecy arrangements in party-line systems

Description

No. 829,964 PATENTED MAY Ba 1985 N. S. MCKIN$EY 5a A. R. NELSON.
SELECTIVE TELEPEGNB.
APELIGATION FILED 1336.213 19m,
0 D'EZET" *SHEBT 4,
ing is a specification.
an enlarged View of the i on each pair of wires will depend upon the do Um TED STATES PATENT OFFICE.
NOBLE s. MGKINSEY AND ANTON R. NELSON, or sosanvnits, canirosnm.
SELECTIVE TELEPHONE.
No. 820,064. Specification of Application filed December 2?, 1964. Serial Zio- 238,2?6.
Tamil whom it may concern.-
Be it known. that we, NonLE S. McKmsEY and Anron R. NnLsoN, citizens of the United States, residing at Susanville, in the county of Lesson and State of California, have invented certain new and useful Improvements in Selective Telephones, of which the follow- Our invention relates to improvements in selective telephones, the object of the invention being to provide a tale hone of such construction that a number them can be used on the same line, and a number of such lines can be connected to a central station, andin which the talking between any arty on one line and a arty called on anot or line shall be absolute y secret and under the control of the part Y calling.
a comparative structioni In the accompanying drawings, Figure 1 is a riew of the mechanism on the inner side of the door of the tcle hone-box, which box con tains the battery, liere not shown. Fig. 2 is y simple and inexpensive ccn= rincipal part of the operating mechanism. 'g. 3 is a dia rammatic View of the system as a whole. ig. 4 is a horizontal section showing the selecting mechanism in top plan ViB'W. Figs. 5 and o are broken front views in two different positions, showing the control of the rotating mechanism by the magnets. Fig. 7 is a broken perspective view of the ends of the le versoperated by the armatnrcs. Fig. 8 is a perspective View of said levers detached from said armatures. front views showing different positions of the line-controller and of the busy signal regulated thereby. Figs. 11 and i2 are corres ending front views of the busy signal.
lg. 13 is a diagrammatic View of the connections in the telephone. Fig. 14 is a diagrammatic View in a simple form of the connec tions of the system. Fig. 15 is a perspective View of the jack, and Figs. 16 and l7 are per spcctive views of the plugs.
General character of the system.The system is one having a central station and an 111- definite number of pairs of wires proceeding therefrom, and each pair of Wires has a, con venient number of parties telephones connected therewith. The number of telephones .f A furt er obfeot is to obtain this result with V Figs. 9 and 16 are broken Letters Patent. istented May 8, 1906.
mend for service and the tariffs paid by the parties; in Fig. 3 there are shown only two of such lines or pairs of Wires leading from the central station; hut it is to he understood that there may be any number thereof. Vvith each line are shown connected only two parties telephones; but any suitable number may be so connected. Primes are added to the numerals in this figure to conveniently dis- 1 the circuits and arts on the right of the figure irom those on t e left. {if the two line-wires l 2 for each group of parties on the same line, the wire 1 is grounded at central, as shown st 3. and has therein a rnsin hatter;
4 and a resistance 5. This resistance is greater than that of any talking-circuit in the system to prevent the talking passing said Colic centrcL-Any party lifting his resin'tlie automatic heels 5 ant-ornaty aliscentral in the following manner: Seid hook then rises under the action of a. spring 8, and a pin 9 thereon engages the un der side of the horizontal end of a resilient lower 1portion 10 of a. line-controller 11, the 'main od y of the line-controller being pivoted on a shaft .12, extending between the front and rear plates of the frame 13 of a clockwork mechanism 15. A light spring 16, coiled about the shaft 12, havin one end hooked over a bracket 17 on the door 18 of the t8l8E1GH6bUX"19, and the other end passed t cngh an spertnre in an extension 20 of said lins=contfo ler 11, normally moves the upper part of said controller upward and the'lrnr sspsrt downward. When the linecnnt 1r 1* is thus raised, its resilient per tion lfi is firefight into contact with two 'spring oontect 2122. The lower contact 21 V. s; i iire 23 with a bent or piste bracket 24, (forming a support for three sire *of airing-contacts hereinafter descri edg whio inst-e 24 is again connected by a wire 25 with the upper terminal 26 of a resistancecoil 27, the lowerterminal 28 of said coil being connected by a wire 29 to a lnnge 30 of the sins: of the telephone-box, whence a wire 31 cadets ground at 32. A oailin =circuit is thns'oornpleted as follows: groun 32, 3% wire 29, coil 27, wire 25; piste "'2 ssss23.;contact 21, line-controller spring 'In,i-:fiocfwork frame 13, wire 33,?1i'rige 34, one 35', wire 2, to central, coil 36 ol'clslling drop magnet, wire 1, resistance 5, battery 4,
ground Tho culling-limp magnet is thus onorgizml, rolousing tho :lrop mnl milling woo trnl.
Talking to rmtruh t ontral now lnsorts: a
plug 37, connected to u wiro 62 of her with in the jot-k 3E3 oi the rnllingqiartys lino, thus eonnonting the two wines of hog plug-cord with the wiros l I! znni thus vomit-Ming hor talking; "unit 40. through tho listonin 4:1, with tho tnllring-rireuit of the (R1 our arty. This rain-nit was complottoil by tinif'ting of the hook, as follows: Upon tinhmokot 24 are sot-ureil sovon contortplates,
sfipurulml by insniotbig-plates 42. Three ol' 48 are there-fora (lifilTCSSPd when tho triophono is on the boo llllll rise by their own spring when tho lolrrphone is lilterl. 'llu'rw fore Whrn the calling party lifts his hook tho plate 44 on rising contacts with the luto 42; above it anti the plate 46 brooks mutant! with the plate 47 below it out] oontartswith tin 3 This oonneots the party:
plate above it. 7 secondary talliingpt-i rvui t with the tLllUTI,I('Ii-- unit at central as follows: receiver 6, wiro oonnoetion 55, wire 56%, plate 45, late 46, w t 59, clrmkwork-l'raino 13, wire 33, tinge 34, wire 35, lino-Wi re 2, spring 6G of the jack, tip (ii of 1 plug 37, win (32, wire 63, listening-la r 41, talking-circuit 1U, listoniug-key 41, wire 64", condenser 65, wiro no, shank 67 of plug Ii? ring 68 of jack BEL contort 69, spring 70, linewire 1. wire 71, hiugo T2, wiro 73, pinto 43, plate 4 1, wiro Tl, soe-onilary coil T5, wire 76, condenser U, win: TS terminal 79, wire 80, receiver 6. llio'priniary talking-circuit of the willing party also eompletod as follows: battery 81, wire E42 to point 83, wire 84 to primary coil 55, wire '86, transmitter 87, wire 88, binrlingqmst S9,.wire (it) to point. 55, wire- 56, into 4 5, plate 46, wire 59,olockwork-t'ramo -13, ineuzontroller spring 10, contziot wiro 91 to battery 8 In this way the calling party may be plot-oil through his junk in. tiillimg ooinmunirntiou with ljfinitlfll. This primary talking-(innit is supplied from the sumo battery 81 as the boll-circuit, hut pro- \ision is made for continuously closing the bell-rircuit, amllhus preven ting; the boil ringing whenever the [)Illllill) tnlking-eirruit is olosed and at tho sumo t me throwing oil it shunt which was ilIUUlltl tho receiver lllltl "tosses through the bell-:.n'niatuio, this shunt heing provider], as ilOIPlXlltitOl elosrrihoil, in order toobtn in sorrow on the line, the brain-h through the boll-(oils prom-oiling; ns io'llon 1: point 83, wire $113. terminal 93, win- 'Jl bellcoils '35, wire 96 honInwnvontzirt flit, wire 3H,
l l l l torininul Wil niro 100 to point whence 1m n'mut Illliltlil through the buttery H1 to tho point Hi. in rommim with tho primary tulltingwirruit. Thus the ourront from tho bntiory ciirillon mnl prom-oils pmtl? through thogiiinmr i hlll l tfllt'tlilftlltlpzll'ilftln?.H;fl') tho lwll-nnigne roils uinl thus whrnovor tho [winiurv tnlliing-oirt'uit is rloseil the bellnnignvts urn onvrgizeri and the hiunnor is llft tl (Lise up to tho gong iiinl tho shunt :n'ouu l tho rooeiver is oponml at UT, this shunt bring us i'i'iilous' point 79, win 11H, l lllfllltg-ptlfil M5, humlnol spring rontuct l'ltl. i121Hltlltl-$)jl1l}' llll, springyoontnot 182,
'tf'll'lt't it? won,- binding-post SJ, wire 1W, non]! 5:3, This spring-contnot it is atoirlml to tho ln-ll-lnnuiner urn'n'ituro HT and \ZlfitiHH therewith uinl when the bellwoils one rnrrgizoil is withdrawn from the Contact .l'i. breaking the shunt tlIUlliHl tln- IQH'lVQl oi uliowing tin rem-Evin to be u'sorl.
liillfilflf] up milm' party.-(lontml having iisttfl tii lttll from tho calling party the numbm' nnotr-ili insr-rts tho plug 37 into the otllor ool; 3%!" ol' the line on which is the rolled pfiti'ty s telepbono, Silo can thersihy complete 2L rirrlsit through tho selector-nu|guets of all tho north on tho lino on which is the t'ttlliii nort r s te-lophono, snitl oirellit tossing to tho ground at erontrnl and also at thrvallin znig, station, (in inserting contacts H32 10;! of ringing-koy Hill at 1114 104 the rirr'uit is as follows: ground 32,wire it] hinge 3th wir 2f resistunce 27, Wire 25, plato- 24, wiro 121i, srringwont:n't 21, lille-i-iontrollor sprin (l, (not'lrworlr-frarno l3}, n'iro 3Z3, hinge I54, wiro 353, win 2, spring til) of inch 39, tip 6 of nlugill, wire (52, contacts ltll Hi2, Wires i05- ltlt'i, ringing-hey ltlil wiros lilti l' 5, contarts Hi2 ltll'. n'ii' 62, tip til, sprin g 6t), wiro 2,Ll1!oi:"i'1lii then clivnlin; on t passing at each station through win 235" lingo 34", Wirr 323", wiro 1H7, nnrgnvtwoil Hits" wire 109, hino'o wire Tl then to the vonnnon wi'- l mnturt 6'), wire l rosislnln-o 5', hitter. i to ground at 3. MLr-oih that are bridged on tho linos lnivo the snow resistnnco, so that n pro iortional amount oi tho current also passos t, lrongli tho ealling-nnl jnot coils I36", releasing t ho rlrop for the oullml line.
It is to be nu: orstooil that tho innortion of the plug 37' in the incl; Hoes not break tho vontnot no. This is only broken when a thirtl plug Ill is usw this plug being used "o hon tho party rulleei is on the sumo partyline as the purty rolling. in tho lotto? onso tho plug 37 is rvlnoveil inn? is replzu-eby the pluggl l l. the tip 1T2 of which ronturts with the spring; Tl] of tho jurlr all the magnets on both lines more strongly than before, thereby attracting in each magnet the more distant armature and brin ing all the wheels immediately back to t eir former positions, breaking in the called partys telephone the circuit between the finger 137 and the arm 138. This at the same time operates the clearing-out drop 150, which has a stronger spring than that of the other magnets, although of the same resist ance, so that it only operates when a strong current is passed through the line.
When the armature 122 is drawn down to the magnet, both of the stops 135 136 rise to such a position that both of the studs 134 can pass said stops freely, permitting the inion 130 to revolve rapidlv and the gear 1 1 also to revolve freely until an arm 152, carried by said gear-wheel, impinges against a stop 153, carried on one of the side su porting-bars128, which brings the gear-whee 131 to its zero or normal position. All of the gear-wheels on all of the telephones on both lines are by the greater energization of the magnets brought to this zero position, and then u on the release of the armature 122 by the reaking of the circuit, as will be presently described, the stop 135 drops into such a position as to arrest a stud 134 on the pinion 130 and allow the gear-wheel to advance a portion of a ste but since this operation of bringing to t e starting position depends u on both of these stops 135 136 being out o the path of the studs 134 a sullicient length of time to permit the finger l52ito revolve with the gearwheel 131 back tothe zero position, it is necessary that this armature 122 be held down a suflicient length of time to allow this movement to take place. Since this movement is caused by shunting the resistance 27, and since the resistance is shunted by connecting the two lower spring-plates 48 =19, which is done by the depression of the hook, and since the hook when in its u per position holds up the controller against t 10 contact 21, thereby closing a break in the circuit through the magnets, it would happen unless otherwise provided that the same movement which would shunt this resistance and therefore energize the magnets more strongly would also break the very circuit by which they are energized, and although they mignt be energized for an instant of time, yet before the magnets would perform their full function the circuit \VOIlfll be broken and the restilt would be that the armature 122 would not remain down a suflicient length of time to permit the finger 152 to reach the stop 1 53; but by the armature 122 rising again from the action of its spring and from the fact that the circuit was broken, stop 135 would arrest a stud 134 and stop the gear-whcel before it fully returned to its normal position. To obviate this, there is provided on the back of the gear-wheel a crown-wheel 155, having a gap 156 therein, through which can fall a in 157, secured upon the linecontroller. is pin is in this gap when the gear-wheel is in its normal or zero position, the line-controller then being supported by a lug 158 thereon, resting upon a pin 159, extending rearwardly from the gear-wheel. The in 157 is raised out of the gap when the inc-controller is raised, so that it lies at a greater distance from the center of the gear-wheel than from the radius of the crownwhcel.
partys line are energized, causing all the gear-wheels 131 to advance a short distance, carrying the gaps 156 beyond the pins 157, so that the pin 0 the party calling whose receiver alone is oil the hook and whose linocontroller has been raised lies on the to) of the crown-wheel, and therefore on the ea in party hanging up, the line-controller is hel up in contact with the contact-s ring 22 by the pin 157 traveling on the top 0 the crownwheel until the pin 157 again. reaches the gap in the crown-whecl and drops through the same, which it only d oes when the gear-Wheel has arrived at its normal or zero position. This insures that the current remains unbroken through the magnets sufliciently long to hold the armature out of the path of the studs 134 until the gear-wheels are all brought to zero.
Secrecy of the tolk'ing.-The line is secret both as regards other parties on the calling artys line and others on the called artys ine. As to the other telephones on the cab ing partys line, as soon as the calling arty takes down his receiver he energizes all the magnets on his line as well as the magnet of the calling drop at central. These magnets are all of the same resistance, and the battery is increased in strength to produce a uniform current through each magnet according as the number of parties on the line and the number of magnets is increased. All these magnets on his own line being energized with a weak current (the calling party having thrown in the resistance 27) all the armatures 121 are attracted and all the gearwheels advance a part of a complete step, being arrested by the other studs 134 striking the stops 136 Immediately that the gearwhecls advance the pins 159, extending rearwardly therefrom, move out from under the lugs 158 on the line-controllers, and said linecontrollers being no longer supported drop, and the pins 157 thereon drop inward from the gap 156 and are inside the crown-wheels 155. Each such line controller is then dropped into such position that the extreme end of the resilient portion 10 thereof is passed by untouched by the ping on the hook, so that the other parties on the line can now no longer operate their line-eontrollers byremoving their receivers from the hook. Therefore they cannot close the circuit on the line By the rise of the hook all the magnets on the callinga rotating device advanced ing wire of any of any talki.ng-circuit in the system, means for connecting at central the other wire of said line with the corresponding wire of any other party linc of the system, scicctor-magnets at each station bridging the wires of the party-line, and means at each station for grounding szticl other Wire, means, wntrolled step by step by successivc cnergizaitions of magncts oi the other lino, for closing in succcssion the twllrircuits of sniel other lincs, substunt hilly as described.
In a selective telephonic system, it party line, one wire of which grounds at central, a resistance therein a t central grcntcr than that of any talking-circuit in the system, magnets at each station bridging said wirc "with the other wire of the line, means at each sta tion for grounding said othr'r wire, and men us at central for connecting said other wire through an interrupter with the roziwponit other party-l no and also for inserting in thc first wire at cent mi an interrupter, whereby the magnets on either line can be intermittently energizcil by cntml, substantially as described.
6. In a selective telophonc systcin, a. partyline of which one wire grounds at central, a resistance therein at central greater han that of any talkingwircuit in the systciu, magnets at each station bridging said Wll'c with the other wire, incuns at each station or frltlllflilig said other Wire, anal means at central to! inserting in said llI'rEt wire on intcrruptvr whereby the magnets can be intcrmitlenily energized, substantially {1H described.
7. in 1 selective iclcphonc systenz, a partyline of which one wire grounds at awntrul, a resistance therein at rem ml grciitcrthan that of any talkingwircuit in thc system, nmgncts at each station bridging swirl wirc with the other Wire, means at Pro-h station for j [l"i)lllltling said other wire, and mourn: tor ins-citing in said first wire an intcrrupta-r a h nchy the magnets can bc interiui triaily cri grizwi. substantially as dcsrribmi.
8. In a scloctive tclcpizonc vstcru, row troi-lng mechanism con in hi and it slim t dish-nun when a weak current passes i hrough th magnets and a long distuncc in the sonic dim-t ion when a strong current pa ses ih rcltwmuli and means for throwing a resistance int 3 line through the magnets by' rcceivcr, sul'istiintiiilly ;1 a dust I 4 ii. in it sclcctivc l-iltl llullt" s rsbm trolling mecluinism r-tiu 'irinin a rotating rlcvice uilvmwwi a ii in tho Sitilllf direction uiicn a vi passes through the magnets llti tancc when a strong current cu l flt't'! through and means opcrulahlrby the milling party for throwing a rcsislunri into the l no through the mugncts, sub-mint o scribcd.
- rests the rotatin i In a selective telephone system, conrolling mechanism CUITlPI'lSlIIg a rotating deicc, cloch'erorhmechanism for rotating the same, stops f or the same arrcs ting the device, the one after a long movement thereof and tho other after a. short movement, a magnet, means whereby the first stop is brought into action by n strong current tlu'ough said Jnag not, and the second stop by a Weak current thercthrough, and means operated by taking down the rccciver for throwin a, resistance into circuit with the coil throng the magnet, substantially as described.
H. in a selective telephone system, controlling mechanism comprising a rotating derice, clockwork mechanism for rotating the same, stops for thesame arresting the device the one after a long movement thereof and the other after a short movement, a magnet, means whereby the first sto is brought into action by a strong current t ough said mag- .nct, and the second stop by a weak current thcrethrough, and means operatable by the calling party for throwing a resistance into circuit with the coil through the magnet, substantially as described.
iii. In a sclcctivc telephone system, controlling mcchanism comprising a. rotating device, clockwork mechanism for rotating the same, arrestiu mcans thcrefor, a magnet for operating thc lattcr, means for interrupting the currents through the magnet repeatedly in succcssion with a weak current, a. circuit closed after a predetermined number of such interruptions, and means wherein. a strong current through the magnet removes the arrcsting means to break said circuit, and ardcvicc in a subsequent position thereof, iinhstantially as described.
13. In a selective telephone system, partyliii one wire of each of which is grounded at central, a rcsist ancc thcrcin at central greats/r Man that of any talkingmircuit in the system: and the other wire of any line can be conuci tml at neutral withtlie corresponding v'iii'c cl any other line, means for grounding said othcr wire at any station of the linc, and whereby trai can connect the two on. on any line, to form a. irc'uit, substantially as docoropirtr tailriiw srriln-d H. in a who live telephone system, aatepily+i=fji r tating (it-vice, clockwork inechan ism t w ritnlillgg' the some, it magnet controlling thrumo interrupted ircak currents Em l,hrough 'm for simultaneously clos ar fl'l'i'lll through said magnet and rin a l V unce into said circuit to a caiwu the cur it to be subsequently so intr-rrupiwl means [or shunting the rcsista'ncc lo pa: rong rurrcnt through tho magnet minor \vbcrrby said strong; current returns thri da ing duviccto its initial position, and illiklnx to." holding the lino closed upon open ating said shunting mamas until said Infating devicu has [Tun-110d tuits initial] pusiLi0n,sui) stuntiuiiy 21$ zifisi-riimd.
15. In a sviwfiiw Wiupimnu Sysimn, :1, line-- coliimilm' M. Qitf'ii simian, mum; L naiming the circuit. by said ii'm'-mmtmiinr, mmns whereby the risv of LisriLlltUIlHLLiC hunk operates the HD9410i i'uiifil in (-1050 the circuit, means fur mippurting time linwcontmiler in a posit-i031 in im su um: ii-Mad by the rise of he automatic book, a?! (i 11103116; V;i](Iui' y the (:11 1S- ing of the circuit iuilumms all the supporting means on the line Lu withdraw the contrailers except Lh'q (me already upnmtcd nut 05 POSiiLiOIl to he so operated by the rise in the corresponding miimmitic imuk, substantially as dn-au-i bud. V
16. In aseicctive ifiipilffljfi sji'siivm, a linecontrulleii' at each shit-inn, means fur (lasing the circuit, by saidlinc-contrniier, means whereby the rise of the autumaitiu hook Qperates the iine-cnntrolier Lu ohms tw Pin-nit, mvans '01- supporting the Him-muimlim' in a pus-H1011 0 im so npm'iitiwi ii) iii!" {ism i Hit: allifimziiaii iwuk, and 'ii1v:'|,11..-x-.vii i-vh; wri a: ing Hi am: circuii iniiuciuuw: ii! iii 11mins on the iziua Lu witiniizw ivrs exeepf ha um, i).ilUfLli position to be so npnmimi My currcspunding autunmiic imv signal bm'ught into .sigmiiu nqiuabion of the suppnrii Liaiiy as described in witne'ss whereof Wu Ewan: our hands in the pmmua-v wit aessc. a
sat
NOBLE ANTOY ii 1;
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