Connector for sector conductor cables

Jan. 23, 1940. _E. d. eby 2,188,178

CONNECTOR FOR SECTOR CONDUCTOR CABLES Filed Sept. 16, 1938

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Patented Jan. 23, 1940

2,188,178

UNITED STATES PATENT OFFICE

2,188,178 CONNECTOR FOR SECTOR CONDUCTOR CABLES

Eugene D. Eby, Pittsfield, Mass., assignor to General Electric Company, a corporation of New York

Application September 16,1938, Serial No. 230,259

Claims.

The present practice in jointing corresponding stranded conductors of multi-conductor cables is to use tubular connector sleeves with cylindrical bores, which are longitudinally split or slotted in order to receive molten solder for uniting the parts. Such a split connector can be opened or closed sufficiently to accommodate irregularly shaped conductors, and also it can be bent or squeezed around the conductors to a 10 limited extent for the purpose of reducing the size thereof and also the size of the solder cavities. In the case of sector conductors, the ends to be connected may not match, and this has to be taken care of as well as possible by bending or twisting the split connector sleeve between its ends and by compressing the wall thereof inwardly to conform as closely as possible to the shape of the conductors. As will be appreciated, much depends upon the skill of the jointer whether the joint is properly made. It will also be appreciated that with such tools as are available for use by a jointer, the connector after its application is liable to have solder cavities which are too large and also to present irregularities on the outer surface thereof which render it more difficult to properly insulate.

It is desirable for many reasons, including the fire hazard, to use solderless connectors for uniting adjacent cable ends. To be satisfactory, a pressure-attached connector must be in the form of a tube without a slot, and its bore must conform closely to the size and shape of the conductors. Such a connector cannot be shaped in the field by means available to the jointer, who commonly does his work in a manhole. Furthermore, a plain tubular sleeve for pressure application is not adapted for use where the ends of conductors to be jointed are of segmental or sector shape and fail to match.

An object of my invention is the provision of an improved connector for stranded sector type conductor cables.

A further object of my invention is the provision of an improved connector for stranded sector conductors in which the strands of the conductors are initially snugly seated within the bore thereof with means for taking care of such angular misalignment of the conductor ends as may be encountered in service.

For a consideration of what I believe to be novel and my invention, attention is directed to the accompanying description and claims appended thereto.

In the accompanying drawing, which is illus. trative of my invention. Fig. 1 is a perspective (Cl. 174—90) view of a three-conductor sector type cable; Fig. 2 is a cross-section thereof; Fig. 3 is an exploded view of a three-part connector; Fig. 4 is a sectional view of a three-part connector as applied to a pair of cable ends; and Fig. 5 is a view of a 5 modified form of connector made of two pieces.

In Fig. 1, 6 indicates the sheath of a cable made of lead or other suitable material. Inside of the sheath are three stranded sector conductors 7, each having a covering of paper or other mate- 10 rial 8 to insulate it from the others, and from the sheath. 9 indicates a metal element resembling a coiled open-spiral spring, which supports the sheath and also serves as a channel or conduit for conveying insulating fluid the length of the ^ucable.

The connector first to be. described is made of three principal pieces 10, II and 12, the inner parts or members being in telescopic relation with the outer part or member. Members 10 and II gQ are counter-parts and each has a bore of such size and shape as snugly to fit the outside dimensions of a stranded sector conductor. As shown, the bore of each part or element 10 and 11 is preformed or machined to sector shape, gg thereby avoiding distorting the metal of the connector part or the strands in any way. The individual conductors of a cable are twisted or cabled together with a relatively long pitch, lay or spiral, and in Cutting the cable preparatory to jointing, the ends of each pair of conductors may not occupy exactly the same angular positions. To emphasize this feature by way of example, the lower part of Fig. 3 shows the apex of the lefthand conductor facing the observer while the M apex of the right-hand conductor faces the rear. The outer end of each connector part is beveled at 13 so as to avoid the formation of shoulders where the concentration of electric stresses might be unduly great. The half connectors or mem- &lt;q bers are individually slipped over the conductor ends and they make a snug fit thereon. The next step is to slip the third part or member 12 of the connector in place, after which it is indented by punches 16 and 17 indicated in Fig. 4. The ends 45 of the conductors, especially when they are of the sector type, are stiff and relatively unyielding, and any pressure applied to change their respective angular position or shape has a tendency to disturb the insulation and may if great care is H not exercised result in damage thereto. By using cylindrical parts or elements such as 10 and II and an outer cylindrical member 12, the parts being free to adjust or turn one with respect to the other, no distortion or twisting of the con

2,188,178 ductors is necessary and hence there can be no injury to the insulation. Nor is any modification of the shape of the conductors necessary. In this connection it is to be noted that the angular posi5 tion of each of the parts 10 and I i is determined by the angular position of the conductors because of the shape thereof. The outer or center member 12 of the connector has beveled ends 18, the bevel forming in effect a continuation of the 10 bevel 13 and for the same reason.

In Fig. 4 the parts are shown in their assembled position. Provided the parts of the connector are not too thick the indenting of the inner and outer parts may be done simultaneously with the 15. result of effecting a saving in cost of the jointing operations. In this case the indents in the outer and inner parts are aligned on each side of the center of the connector and extend axially. This is the arrangement, shown in Fig. 4. During the 20 pressing operation the respective ends of the conductors to be joined are separated or splayed: afterwards they are insulated and then pushed inwardly toward the axis of the cables in order to reduce the diameter of the joint casing enclos25 ing them.

In Fig. 5 is shown a modified form of the connector made of two pieces or members instead of three. In this illustration 20 indicates the right-hand part of the connector, and 21 the 30 tubular part corresponding in function to the tubular member 12 of Fig. 3. Thus in preparing the part 20, one end thereof has a preformed bore which conforms in shape and size to the sector conductor 22 inserted therein. The left35 hand or cylindrical part 21 is counter-bored as indicated by the dotted lines 23 to form a socket, the dotted line 24 indicating a shoulder or seat for the companion part of the connector. The right-hand end of the part 20 is beveled as in40 dicated at 25 to avoid the formation of a radial shoulder where there would be a concentration of electrical stresses. Furthermore, the beveling of the end of this and also of the construction shown in Fig. 4 simplifies the taping of the connector for insulating purposes.

The left-hand member or element has a cylindrical portion 26 containing a bore 27 of sector shape preformed as to size and shape to conform to the stranded sector conductor 28. It is also provided with a collar 29, the left-hand side of which is beveled at 30 for the reasons above indicated. The side of the collar opposite the beveled end is perpendicular to the axis and is arranged to seat on one end of the member 21 55 of the other portion of the connector. The parts or members 20 and 26 are first applied to the sector conductors after which the part 26 is inserted in the cylindrical socket 23 of the other part. After assembly the right-hand member is ¢0 indented by the punches 31 and 32 which has the effect of securely anchoring the conductors in the connector and also uniting the parts of the connector. If desired the right-hand part may be secured to the conductor before assem55 bly by actuating the punch 31 by a suitable press, and after assembly the punch 32 may be similarly actuated. The action of the punch not only indents the wall of the socket, but also Indents the part 26 to cause form union with the strands 70 of conductor 28. Because the part 26 has a smooth cylindrical exterior and the socket 23 has' a cylindrical inner wall, the two snugly fitting in telescopic relation, there will be no straining or twisting of the segmental conductors when the 75 connector is assembled in place. The respective positions of the sector conductors determines the angular position of the respective parts.

The parts 10 and II are desirably made of relatively thin metal so that the punching operations will properly indent the outer cylindrical member 12 as well as the inner parts 10 and li, and in so doing force or wedge the strands of the conductors Into firm contact with the enclosing wall. Copper is a suitable metal for the connector parts. The parts of the connector may be made from special tubing drawn to the particular size required, or they may be made from cylindrical tubing which is subsequently reshaped to give the sector contour after which the outer surface is machined to cylindrical form. As a further alternative they may be forged to the de15 sired shape and size.

Another advantage of my improved construction resides in the fact that a conductor of a given shape and size may be united with an- ²⁰other conductor of different shape or size or differing both in shape and size by merely changing one part of the connector, for example, the part 10 of Fig. 3 or the part 26 of Fig. 5. Also one of the parts such as 10 in Fig. 3 or 26 in ²⁸Fig. 5 may be regarded as a terminal lug for connecting a cable to a terminal structure and shaped accordingly.