US1841292A - Transmission line clamp - Google Patents

Description

Jan. 12, 1932. w. P. LARK TRANSMISSION LINE CLAMP Filed March 28, 1929 INVENTOR. ,PLQf/fl,

ATTORNEZ Patented Jan. 12,1932

TRANSMISSION LmncLAnrP Application filed Marcl128, 1929. SeriaiNoJ35Qg789i, a

The present invention consists of a trans-,

mission line clamp, an objector which is toprovide a'cable suspension member which is adapted to hang the cable without theuse of snatch blocks or like hoisting means heretofore employed for engagingthe cable with the conventional insulator clamp.

Another object of the invention is toprovide a clamp in which the cable may be hoisted and then tensioned, after which the cable. is positively secured from *moVement or displacement. V

A further object of ;.the invention is to providea transmission line clamp which may be utilized for hoisting the clamp to the insulator group and the cable stretched there-, through to the'desired degree of tension, pursuant to whichthe cable may beclamped into a fixed position in a facile and expeditious mannen- J V y A 'stillfurther object of the invention ;is to provide a clamp through which the cable may be stretched and afterwards secured, the clamp being equippedwith highly conduc tive metal to increase'conductivity at the same time reducing frictional resistance during'the cable-tensioning operation to a minimum.

Other objects ofthe invention will heapparent from the following descriptionof the present preferred forinof the invention,

aken in connection with theaccompanying drawings, wherein Fig. 1 is a side elevational view of a transi mission line clamp constructed in accordance with the present invention, illustrating the application of the same; I

V Fig. 2 is a longitudinal sectional view of the line clamp, showing the cable linein dotted lines, andrillustrating the, clamp applied to the insulator arm, ,the latten beingg shown fragmentarily Fig. 3 is a verticalsectional view, taken on the line 3-3 of Fig.2, looking the rection of the arrow;..

"Fi .4 is a'vertical sectional. view, ftaken on theline 4-4101 Fig. 2, lookinginthe di rection oi:"the"arro.w;

,tion'7 of the cross-arm of a line wire and isequipped on the freeterminal'with eye '8. i of discal insulators 9 fromith'eilowermost of 60,

.versely across the frame and j with a; wear 1 the V roller.

Fig.5 isa vertical sectional view,taken on the line 5 ri igi 2,1aaag hermal-Lon 1 of the arrow'; and l Fig. 6 is a plan View of the clamp plate, f 7

In the drawings, in orderto illustrate the I .appl1cat1on of the present invention,

is shown, whichis, of; conventional. design, an

The, eye pendently carries a; group which a'narm lO pen'ds; g The clamp constructedin accordance with thepresent inventionis'generally'designatedl an mbodi s i c y p n a d:

a clamping plate-l2. The frameof the c amp; consists ofparallel side plates; 13, which are integrally connected through the medium of webs 14,- the inner facesofthe latterbeing concaved and preferably plated or otherwise equipped with a highlylconductive film15, l .madeof aluminum composition or like mate- 1 rial. Transmissionline receiving saddlesare" thereby provided. The webs 14 extend trans- 16 mounted therebetween. Rollers, 17.21MB

mountedbetweenthe plates 13 atthe ends of the frame, beyond-the outer terminals of the,

.webs -14. .Tlie; outer terminals of the frame extend downwardly beyond-the" rollers 17 to -provide iurshaped guard members 18, for f a purpose-more fully-hereinafter set forth,

Each of the rollerslfi and 17 is preferably composed'ofa materialofhighly electrical conductivity, the borefof which is provided being keyed orotherwise fixedly :secured to Each roller is. adapted/to, be ro-' I tata'blymounted ona'shaftor axle 20, which is made of suitable wear-resisting metal, such Ta's malleable steel, the shafts orlaxles being 0. i fixedlysecured-tothe traine. When the roll- Y .e s m m eflini hezirame w b ct j especially. upon regie re 'oe to Fig. 2 fofthef drawings, that the vertlces of the cable -im- ,4 pinging portions'thereof arein a plane above h Plane f f heii we p r ions a;

the fra e, ,Consequently,when amnesia; 1

line cable,-,}suclras indicat ed at21,.1is drawnthro'ugh the clamp, the cable. willjpass 1 00 j freel y over merciless clear the I p ate 1 havea roller Q I take-up sleevef 19, the flatter 85 p films or saddles 15. The provision of rollers permits the cable to be drawn through the clamp with a minimum resistance. After the cable has been drawn to the desired degree of tension, it may be clamped into fixed threaded as indicated: at 24, and extends through the web 1 1 and is adapted for the reception of a nut 25. The nut 25 is threaded on the shank of its bolt until it is engaged 'with the under face of one of the webs 1 1 or with a washer 26, which is interposed between thenut and the web to thereby draw the bill of the hook downwardly and correspondingly urgethe clamp plate 12 inwardly so as to flex the cable'21 snugly in engagement with the plated films 15 of the webs 14. It

will be noted that the inner face of'the'plate 12 is plated or provided with a covering 27 of highly conductive metal, such as aluminum composition. 1 When the plate 12 is secured serves as a cushion for the cable 21.

in position, as shown in the drawings, it will be'noted that said cable is almost completely encased in the clamp between the bottom and sides of the frame and theclamp plate 12. l/Vhen so clamped, the covering or plating 27 Consequently, po'sssibility of cutting the strands of the cable or of corrosion of the latter, by contact with the rough steel clamp commonly used, is eliminated. The clamp plate is bowed midway its ends, as indicated at 28, to

- conform to the contour of the central'roller quently,

16, above'which it is positioned. Consewhenthe plate 12 is urgedinwardly against ,thecable 21 the latter is fixed from movement against the periphery of'the roller 16. r

The side plates 13 of the frame are provided with intermediate ears 29, which, as shown to advantagein Fig. 3, are, arranged in parallel relation and are provided with openings therein which correspond with openings formed in the insulator armlO and are adapted for the reception of a bolt or pin 30 which is'deta'chably engaged through said ears 29 and arm 10. v

- In engaging transmissionline cables with group insulators on th'e cross-arms of line towers, 1t 1s customary to first engagethe cable with a snatch block which is then hoisted into engagement with the eye 8 of the cross-arm, following which the cable is tensioned to thefdesired degree'and then transferred to a clamp, consisting, of plate U- T he bill of each hook is adapted present invention, with shaped in cross-section, which is pendently supported by the insulator group. This procedure is both costly and laborious. With the present invention the use of snatch blocks is eliminated, since the clamp is directly engaged with the insulator group on the ground and the cable mounted in the clamp, after which the insulator group and clamp are hoisted into engagement with the eye 8 of the cross-arm, while the cable is slack. This hoisting operation is a simple one and may be performed by the use of an ordinary pulley block and a small expenditure of man-power. After the group of insulators and clamp constructed in accordance with the present invention is secured to the cross-arm, the cable is tensioned in a manner well known in the art, following which the cable is positively secured from displacement, in a manner already described. It is desirable to main the clamp, material of high electrical conductivity which is usuallyra soft metal and consequently issubject to rapid wear by the frictional resistance set up when a cable is pulled therethrough. By the provision of rollers, as herein set out, the cable is drawn through the clamp with an'almost completeabsence of frictional resistance, since the cable, by reason of the peculiar positioning of the rollers, comes in contact with no part of the clamp body." However, by reason of the structure above described, when the cable is clampedfrom movement in the present invention, it is almost completelyhoused by a casingofhigh electrical conductivity,with obvious desirable advantages. Complete assemblage of the clamp and insulator group on the ground may be effected by use of the p 7 the exception ofthe clamp plate 12, which may be inserted in the clamp body above the cable after the latter has been tensioned. It will be noted that the plates 13 are recessed, as indicated at 31, for the reception of the clamping bolts 22, the bills of the latter being'adapted to rest in semi-circular recesses theupper margins of the plates 13, during the tensioning operation of the cable. As soon as the cable has been tensioned and the plate 12 positioned on top of the cable, the clamping bolts 22are rotatedso as to engage the bills of the bolts in the. recesses 23 of the clamp plates, as heretofore described. The provision of the guards 18 prevent the cable from flexing downwardly, so as to also prevent drag-againsttherollers 17 during the tensioning operation of the cable. This further eliminates the possibility ofany undue friction .or wear. on the rollers. i

' Although the present invention is shown as especially adapted" for use with soft metal Jcable, it is nevertheless to be understood that the: clamp is" equally I applicable for use with hard metal cable and correspondingly, the

re le te am beer i fl e la y be 32 which areformedin made of hard metal' throughout. The manner of associating the clamp with the insulator group and the theory of operation remains the same.

While I- have herein described the present preferred form of the invention, it is nevertheless to be understood that various changes may be made in the invention, especially in V the details of construction, proportion and arrangement of parts, within the scope of the claims hereto appended. i

What is claimed is V 1 1. In a cable clamp for the insulators of transmission line towers, includinga clamp embodying a plurality of uniplanar movable cable engaging parts, and means to clam the cable against said parts.

2. In a cable clamp structure, m'obile means to permit: frictionless feeding of the cable therethrough, cable into fixed engagement with said means.

3. In a cable clamp for the insulator group a clamp body of a transmission l ne tower, I equipped with rollers, cable seats formed in the body between said rollers, and means detachably mounted in the body to urge the cable into engagement with said rollers and seats.

with a plating of highly conductive metal, a series of'rollers mounted in the clamp between said seats,

material said plate urging the cable into eugagement with the seats and rollers. v T

5. A cable clamp including a. clamp body equipped with a means engageable through said clamp body and with the clamp plate for urging the latter in the direction of the seats and rollers.

WILLIAM P. LARK.

and means to urge the 4. A cable clamp including a clamp emf bodying cable seats, each of which is equipped.

and a clamping plate 7 equipped withaplating ofhighly conductive series of-rollers and interposed cable seats, a clamp plate mounted in the clamp body over said seats and rollers, and l

Images