US2657371A

US2657371A - Cable clamping device for feeder taps

Info

Publication number: US2657371A
Application number: US165435A
Authority: US
Inventors: Elmo F Huston
Original assignee: Ohio Brass Co
Current assignee: Ohio Brass Co
Priority date: 1950-06-01
Filing date: 1950-06-01
Publication date: 1953-10-27
Anticipated expiration: 1970-10-27

Description

Oct. 27, 1953 E. F. Husum 2,657,311

CABLE CLAMPING DEVICE FOR FEEDER TAPS Filed June 1. 1.950

I INVENTOR. Emo F HUSTQAI BVM M TTOENE YS Patented Oct. 27, 1953 `cLAivr-PING. DEVICE ron FEEDER TAP-s -rElmo, Huston, Mansfield, `Ohio, rassignor to The Ohio Brass Company, Mansfield, Chio, a :corporation ofaNeW Jersey Application .Iune1,'1950, Serial No.165,435

2 claims. l

This invention relates general-ly lto :feeder taps and is particularly concerned with a .feeder :tap having means which spirals ia cable end -i-nto a sector .shape `and clamps itin place. .It .also relates vparticularly to la feeder tap which .is .provided with combined means for venting the casing and adjusting the parts thereof .to-accommodate manufacturing variationsin dimensions.

In prior feeder taps the cable has been attached to one of the fuse-engaging plugs, as by a cap screw and clamp `such as is shown -in Chandler Patent No. 1,822,883, 'or othersecuring means. While these securing means have been used commercially, they have .not been entirely satisfactory and, accordingly, one object .of the present invention is to provide a :new cable -securing means which avoids the disadvantages of the securing means :and possesses new advantages.

Prior feeder taps have been provided with casings which were to :engage at one end ywith'an vinsulating cap and Vents were provided in the cap to relieve pressure within the casing. Manufacturing tolerances often caused `imperfect. Apositioning of the parts within the Vcasing orleft a space between the insulating cap which, under certain conditions of use, .couldibecomelled with wet mud and might then `deliver a charge of electricity to an operator whose hand might come into Contact with the mud. Accordingly, itis another object of this invention to provide an insulating cap which will not only accommodate manufacturing tolerances and insure predetermined relative positioning of the .parts :o'f rthe tap, but will Yalso insure against an operator receiving a shock when in Contact with the guard.

The present invention will bebetter understood by those skilled in the art from the -following specification read in connection-with the vaccompanying drawings, inwhich:

Fig. l is a longitudinal, sectional view'of one form of feeder tap embodying the presentinvention;

Fig. 2'is an `end elevational-view'of the-insulating guard at 'the powerereceiving Aend of the1tap;

Fig. 3 is a cross-sectional view taken `on line 3-3 of Fig. 2;

Fig. .4 `is a detailed sectional view of thecableengaging plug of the tap of -Fg..l,;

Fig. 5 is an end elevational View of the plug at the power-receiving end of the tap;

Fig. 6 is a view, partly in elevation, and partly in section, taken on line 6-6 of Fig. 5;

Fig. '7 is a side elevational View of the fuse of Fig. 1;

Fig. .i8 is a transverse, sectional view taken .on line fil-.sof Figli; and

Fig. .9 isa fragmentary, 4cross-sectional view taken substantially on line 8 8 vof Fig. 4 but showing the wires -.of a power-.delivering r,cable clampedin the plug'ofFig. 4.

In *the drawings, the Aillustrated feeder v.tap comprises an insulating .casing -fconsisting fof -a `tube I and a -lining 2. While various materials may be Yused '.to form .these parts, :it has been found that l'the tube I may consistof phenO-canVaS, i. e., canvas impregnated with aphenol condensation product 'such as Bakelite vor vany vother suitable plastic material. The lining .2 of this tube is preferably composed :of asbestos. As will .be noted, the tube part ii of ythecas'ing is vthreaded at 'eachend `and theliningZ is positioned 'between these threaded portions. An insulating cap .3 is screw-threaded into the power-delivering end of the casing anda sleeve 4 threaded on 'its inner and outer surfaces is screwed into the other or power-receiving :end of Vthe leasing. The lcap 3 andsleeve 4 vmay abut against the `opposite ends of lining 2.

.An electrically conducting plug 5 is screwthreaded intosleeve '4 and carriesat its outer end a iplate V6 to which is vulcanized, or otherwise suitably secured, a guard r'l composed 'of insulating material. The guard .1 isattached to plug 5 as lby Ascrews f8 extending through holes S. It will be noted, -Lbyreference to Fig. i., that ,even when theplug 5 is screwed vinto sleeve as far `as .is permitted .by :parts within the .casing the plate *S will .bespaced ifrom the endof .tube I The .guard 'I has .a Arecess Adefined .by cylindrical sidewall Iii andend wall VH and veach of'these walls is spaced apart from the-adjacent opposedsurfaces of tube l for vpurposes presently to appear.

Therguard is provided with vent holes l2 which are aligned with similar holes I3 extending Vlongitudinally through .plug and opening into the interior of thecasing. Gas .pressure created with- .inthe casing may escape through lholes l2 and I3. The main advantage of the spacingbetween the guard and .casing Aend is vthat manufacturing tolerances Icanbe accommodated .by variation in the dimensions of these spaces as lwill be understood by those skilled in the art.

'The plug 5 has lan axial fopening screwthreaded attire louter fend fto receive 'a conductor I5 which may be connected to a Source of power,

vfor example, by being hooked over a power line. At its inner end this axial opening is threaded to receive a threaded stud 2B attached to or extending through the end cap 2l of fuse casing 22.

The other end of the fuse casing is provided with a similar cap 2l' and threaded stud 20' and the latter stud is threaded into the axial opening in plug 25. The plugs and 25 have tubular end portions facing each other and these portions are slit lengthwise to provide resilient fingers 26 Within which the end caps 2l and 2| of fuse casing 22 may be received and by which they may be frictionally gripped to insure good electrical contact therewith in addition to the contact afforded by the threaded studs 26 and 29. The inner ends of the studs are connected to the ends of the fuse linl; 26".

Plug 25 abuts at its outer end with the insulating cap 3. This plug is provided with a longitudinally extending recess which includes a generally cylindrical portion 36 and a parallel sided portion 3i extending to the periphery of the plug. The cylindrical portion 36 is preferably transversely corrugated as indicated at 32 to present a roughened surface against a cable end which is to be clamped in the recess. A lever or clamp 33 is disposed in portion 3l of the recess and is rotatable on a pin 34. This lever has parallel sides disposed closely adjacent to the sides of recess 3i and has a cam-shaped inner edge surface 35 opposed to the corrugated portion of recess 36. When a cable is to be connected operatively with plug 25 the lever 33 is rotated about pin 34 to the dotted line position to move it away from the corrugated surface 35. Then the cable end is placed in recess 36 and the lever is rotated to the full line position shown in Fig. 4 with resultant clamping, spreading and shifting of the Wires of the cable so that they will move into and substantially ll the sector-shaped part 36 of the cylindrical recess which remains after the lever 33 has been moved into its cable clamping position in Fig. 4. The casing I holds the cam lever 33 in clamping position and thus prevents accidental release of the cable.

It will be understood from the foregoing description that the cam clamping device here illustrated possesses many advantages. It affords a grip with the cable which extends over a large surface area due to the spreading out of the strands of the cable into a sector shape with the cam engaging the inner surface of the sector and impressing the strands against the outer surface of the sector. This clamping device may be operated without the use of tools and the cable cannot be loosened while the feeder tap is in assembled position. It will also be noted that the assembled parts of this invention afford increased venting capacity and part of the space provided for accommodation of manufacturing tolerances may also serve as part of the venting system. The spacing between plate 6 and the adjacent end of the casing i may serve to relieve internal pressure in the casing and also to insure predetermined positioning of the parts of the device in spite of variation in dimensions due to manufacturing tolerances. Another advantage in the present construction is the provision of threaded studs which may be connected to the end caps of the fuse casing 22 which materially supplement the electrical conducting action of the fingers 26,

The corrugation 32 may, in some cases, be omitted, especially when the cable is composed 4 of relatively small Wires, some of which are apt to be injured or even severed by the corrugation.

Having thus described the present invention so that others skilled in the art may be able to understand and practice the same, I state that what I desire to secure by Letters Patent is dened in what is claimed.

What is claimed is:

1. A cable clamping device for use in a feeder tap comprising a fuse-receiving plug having a body portion provided with a longitudinally extending, generally cylindrical, cable-receiving recess of greater cross-sectional area than the cable to be clamped therein, and a cam lever pivoted in said body portion, said lever being of less Width than the diameter of said recess, having a carnshaped, transversely convex inner edge surface delining with the walls of said cable-receiving recess a space of crescent-shaped cross-section of slightly less cross-sectional area than that of the cable to be clamped therein, said cam lever being movable to bring its cam-shaped convex edge surface into the cable-receiving recess and to spread the end of the cable in said recess into substantially all parts of said crescent-shaped space and to clamp the cable in place therein.

2. A cable clamping device for use in a feeder tap comprising a fuse-receiving plug having a body provided with a generally cylindrical recess extending at a small angle to the longitudinal centerline of the plug and having a cross-sectional area considerably larger than that of the cable to be clamped therein, and a parallel-sided recess extending from said cylindrical recess to the periphery of the plug, a cam lever pivotally mounted in said parallel-sided recess and having parallel sides disposed closely adjacent to the sides of said recess and having a cam-shaped, transversely convex inner edge surface, said lever being pivotally movable into a position where its cam-shaped convex surface extends approximately to the axis of the cylindrical recess and defines with the inner surface of the latter recess a crescent-shaped space having a cross-sectional area slightly less than that of the cable to be clamped therein, said cam lever serving, when the cam portion thereof is brought into said cylindrical recess, to spread and shift the wires oi' the cable into, and to lill, substantially al1 parts of the sector-shaped recess and to clamp the cable in place therein.

ELMO F. HUSTON.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,411,263 Bellis Apr. 4, 1922 1,666,991 Cohen Apr. 24, 1923 1,822,883 Chandler Sept. 15, 1931 1,930,594 Marchand Oct. 7, 1933 2,246,193 Smith, Jr. June 17, 1941 2,288,680 Chandler July 7, 1942 2,336,175 I-Iixon Dec. 7, 1943 2,419,152 Mosebach Apr. 15, 1947 2,475,352 Conrad July 5, 1949 FOREIGN PATENTS Number Country Date 26,663 Great Britain of 1906