US1135940A - Lightning-rod cable. - Google Patents

Description

P. J. JUEL.

LIGHTNING ROD CABLE.

APPLICATION FILED APR. 5, 1912.

I Patented Apr. 13, 1915.

Pefer due],

E WE r iifi ur T W lissieuon 110 ms. norrimnom- F;

' a To all whiom z't mag/concern."

I ning-Rod Cables,;of which the followingis;

, Itis the object of myinvention to provide ATLANTIC, Iowa, Am) .0. HArIsEN or; BRAYTON," IOWA: v

. Be it known thatL'PETnn J. J UEL a'citie I zen of the United 'States,'i and a residentof;

Council Bluffs, in I the county of Pottawatr tamie and State of-Iow'a, have invented certain new 'and useful Improvements in Lighta'specification. 1- l 7' r My invention relatesto electrical conduc-1 tors, and more especiallyto cables for'usein' lightning protection:

.a cable for thisflpurposeiwhichiTwill have, a

large surface proportionally to its weight or the amount'of'material employedf in' its construction, and having sufiicient flexibility and tensile strength to amply meet the prac-y tical requirements a for an. article of this kind. a f v 7 5" P:

v A construction embodying myinvention'is illustrated in thenzaccompanying drawings, I in which' 1 a a Figure 1' is'a sidelview of a piece of the cablevhaving the several layers, thereof "suc-'-v cessively' broken away ,;to,sho1w the other e layers disposed within themg and Fig. 2i-is ai transversesectionalyiew of the cableJ I pp It is well known that lightning is a dis .ruptive electrical discharge which causes ins, the conductors through which" it passes alternating or pulsating current of enormously high frequency. I It" is also known that the carrying capacity of conductors for electrical" currents of this nature'is proportional almost entirely to the surface area a rather thanto the sectional area of the conductor.- It is therefore-desirable in a conductor 'for'this purpose thatthe same shall" have a large surface, andin order that a large surface may be provided with the greatest economy of material it isnecessarythat for the inner part of the conductor there,

i shall be usedthe leastamount of material consistent with a suitable tensile strength and lateral stability. It is also'desirable' that the external part of the conductor shall present a a practically continuous surface and yetbe so divided that'itl'willbe Ifiexible. I In: a cable constructed in accordancewith my" invention there are two principal parts;

differing considerably from each other in [.their'structure These parts ,are the outer covering or sheath portion, and the innerori fcore portion of the cable The cable as a whole comprisesa number ,i of concentric rection of-the helices-being the same as those fof'thewiresland 3., 71 l V v a The structurethus far described andcom prising the coreeenter or strand formed the wires l, and the four concentric layers formed theawiresfl, 3," 4 and 5,is the ---cable'-core.w Obviouslyflt may consistof any 7 r desired number of layers of wire, and each negmmaaom m;

,consistlingof helicallyvextending U W all preferably of a metal, suchascop per, having, high conductivity. l r

strandformed by thewires1' are disposed a around the SaidrOre-centerl The direction I of, twist or of adyance of the helices formed Lbythe Wires 2is opposite to that of thewires;

l a they are not contactcwith each other, ,the"

pitch1 of'the helijces being largerproportion- 1-, and the wires 2 are spaced apart; so that" ally! to the diameter of the fwires. a The said is formed by; a pair of wires :3, spaced apart wires 1. "The V fourth} layer isj similarly spaced, apart and disposed helically, the diwires 2; formtwhatmay be-termed the sec? 'ond layer of the cable-core. The thirdl-layerand extendinghelically; the direction ofthe "helices'being oppositeto those of thewires 2, OI'Li IItheS aIIlG; direction as'thos'e of they formedandconsists of a pair of wires{lathe direction of twist-therein being thesameas th ti offthe tawires 2. The ,fifth layer come: prises two pairslof-"wires 5,,which arealso c layer .may be formed by suitable number i "1 of in'diyidual wires: It isipreferablef that as the diameter of'the layers becomesgreater] the number of individual wires used in; a

forming the layer I be increased, though it is Y not necessary to "maintain an exact proportion between the diameter of thelayer and wires Vof'theadjoining layers inside and out- V side' of the layerconsideredi i L The exterior' or [sheath p of the cable/is A a formed by 'a plurality of strands 6,, each I strandbeing formed. by a pair of wires, 7

the number of wires usedflinj forming it. ,It

should "be especiallynoted that except for -;the wires formingthe core-center, the wires of any onelayerof the core do not comein 1 contact with each other butaonly-with the 10 5 65a pain of wires 2, which extend helically, F

twisted together, and the several strands be- 3 ing disposed helically 'around'the core, the

helices. being opposite in direction to: those of the outer layer of'the core. s The number of strands in the sheath; their size, and the pitch of the helices are such that-the-several strands lie in contact with each other and thus present a practically continuous surface at the outsideof the cable;

7 From the foregoing it will be obvious that my, invention provides a 7 cable peculiarly adapted for the purpose set forth. By the alternately reversed direction of twist in the several layers of the-core and the spacing apart of the wires" of each layer, the same are caused to occupy a large space proportional to the actual cross-section of themetal used.

as that occupied by the-sheath, there are employed in the core only twelve wires, while in the sheath-there are twenty-eight wiresor' fourteen strands of two wires each. The cablelthus presents a structure combining economy of material and lightweight, with 1 large surface area high'co'rfiductiyity, flexibility, and tensile strengthsuflicient for therequirements of an article of the practical kind. 7

Now, having described my invention, what I claim and desire" to securev by LettersjPatent is": t i

1. In a lightning-rod cable, acorecomprising a central strandyand a plurality of I concentric layers of wires twisted around Washington, 1 0

Copies of this patent may be obtained for 'lh usin the structure shown; in the drawings; while the sectional area of the space occupied by the core is nearly as large said central strand, each layer comprisinga plurality of helically extending wires spaced apart laterally so that no two wires of the sairie layer are in contact with each other, thed'irection of the helices being opposite in adjoining layers, and a sheath comprising. a plurality of helical multiple-wire strands twisted about the core in adirectionoppositefto that of the wiresin the outer layer of the core, and eachstrand contacting laterally with the strands'adjoining itg 2; In-a lightning-rod cable, acore comprising a central strand consisting of two wires twisted together to forin contacting helices, and a plurality of concentric layers of wires twisted around said central strand, each layer comprising a plurality of helically-e'xtending wires spaced apart laterally so that no two wires of the same layer are incontact with each other, the direction of the helices being opposite in adjoining layers, and a sheath comprising a' plurality of helical str'andstwist'ed about: the'core in a direction opposite to that ofthe wiresfin theouterlayer of the core, each strand of the sheath consisting of two wires twisted "together, and each: strand ofthe sheath being in contact with the strands at each side thereof. 7 a p p 7 r In testimony whereofI-have hereunto subscribed my name in the presence of two wita nesses.

' PETER J. JTJEL WVitne'sses: P

fiy ecents each, by addressing the Commissioner of Patents.

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