US650860A - Electrical connector and method of making same. - Google Patents

Description

' Patented June 5, I900. T. J. McTlGHE.

HECTOR AND METHOD OF MAKING SAME.

( Application filed Feb. 27, 1900.

ELECTRICAL CON (Mo Model.)

Qmibneoow Wvwenboz, 21. %11 alter/M0134 UNITED STATES PATENT- OF ICE.

THOMAS J. MCTIGHE, OF NEW YORK, N. Y.

ELECTRICAL CONNECTOR AND METHOD OF IVlAKlNG SAME.

SPECIFICATION formingpart of Letters Patent No. 650,860, dated'J'une 5, 1900.

'- Application filedl'ehruary 27,1900- Berial lib-6,713. (No modeL) To all whom it "my concern.-

Be it known that I, THOMAS J. MCTIGHE, a citizen of the United States, residing at New York, in the countyof New York and. State of New York, have invented certain new and useful Improvements in Electrical Connectors and Methods of Making the Same; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable'others skilled in the art to which it appertains to make and use the same.

This invention relates to a novel method of splicing or connecting electrical conductors, especially that class known as feeder-cables, whereby two sections of cable of any carrying capacity can be expeditiously and permanently spliced together, forming a compact and soldcrlcss joint of lower resistance per unit of length than the cable itself and having all the mechanical strength required.

The invention consists in the cold compression or swaging method of splicing electrical conductors and in the novel form of splice or joint produced thereby,'both substantially as hereinafter fully described, and set forth in the claims.

In the accompanying drawings, which, form part of this specification, Figure 1 is a side elevation of the ends of two cable-sections with my splicing-sleeve in section prior to compression. Fig. 2 is an end view of same,

showing a pair of compressing-dies ready for application of pressure. Figs. 3 and 4 are cross-sections of the sleeve, showing its shape before and after compression. Fig. 5 is a view similar to Fig. 1, showing the completed joint after powerful compression. Fig.6- is an end View, the same as Fig. 2, but with the dies brought nearly together. Fig. 7 is a side view, partly sectional, showing a modified form of sleeve before compression. Fig. 8 is a similar View after compression; and Fig. 9 is a side view, partly sectional, of, a completed joint of modified character.

Referring to the drawings, my invention is carried out in the following manner: I square off the ends A B of the cable-sectionswhich are to be spliced, strip the insulation (if any) for a few inches, clean the ends, and insert them in a, sleeve 0, preferably of soft cast metal'with clean inner surface. .The crosssection is preferably oval outside, as in Figs. 2 and 3. I then inclose the sleeve C and conductor ends A B between suitable dies D D and apply a powerful pressure to the latter, tending to bring them together, as at Fig. 6. The sleeve 0 yields under the pressure, becoming smaller in diameter and thicker in the wall, while the pressure is transmitted inwardly upon the conductor ends A B, forcing them into a compact mass, occupying only or less than the actual cross-sectional area of the metal of the conductors-that is, the pres sure eliminates all the voids and brings the whole sleeve and the inclosed conductors into a practically-homogeneous mass. Thus when the conductors are composed of a number of wires bunched or stranded the individual wires are forced into one virtuallysolid mass, giving perfect electrical contact from wire to wire and to sleeve. In the joint shown at Figs. 5 and 6 the sectional area of the sleeve is nearly double that of the compacted cable, while the area of surface contact between each cable end and the sleeve is. more than ten times the sectional area of the compacted cable. These conditions give a joint of extreme low resistance electrically. The metal of the sleeve is forced into and fills the external crevices of the cable, as indicated clearly 'at Fig. 4, thus considerably increasing the area of contact. The foregoin g process may be briefly described-as coldswaging. Mechanically such a splice has great strength. The compression hardens and stiffcns the metal, and the tensile strength of the joint is ample for ordinary service. Electrical conductors of cable form are usually connected by stripping the insulation for a considerable length, cleaning, making some form of splice, and then heating and filling all spaces with molten solder. The operation is tedious, requires great skill, and the heat travels back some distance and does more or less damage to the insulation. By my invention I accomplish the splicing in a few moments, remove but a few inches of insulation, use no solder or heat, and produce a better, more permanent, and stronger splice than is possible by the hand method. The operation is the same for all sizes of conductors. Any convenient or suitable source of pressure is applicable, such ashydraulic or screw press or a wedge-press. ll, however, prefer the hydraulic jack-press, which while capable of giving great .pressures is still quite portable and can be carried readily along the line of work for coupling the cable-sections.

Where additional tensile strength is required in the splice, I so shape the sleeve C that when the pressure is appliedit produces one or more peripheral constrictions in the cable, preventing the wires from being pulled out. In Figs. 7 and 8 I'show a specific form of such splice. The sleeve (3 is formed with the external beads e, and the dies D I), having plain surfaces, force these ribs inwardly until a corresponding amount of metal is caused to project on the inside, as at e, and thus produce one or more constricted points f on the cables A 13,-as shown in Fig. 8. A similar effect is produced in Fig. 9, Where the outer dotted lines show the original form of the sleeve, the full lines show the compressed sleeve and cable, and the inner dotted lines show the constricted and compacted cable, the same letters of reference being used as in Figs. 7 and 8 and indicating the same general idea. In Fig. 9, however, I leave the abutting ends of the cables A B practically uncompressed, thus adding to the strength by having a relatively-deep constriction between the compacted zone and the inner end of each section. In this figure I also include the uncompressed guard projections g, corresponding in internal diameter with the normal diameter of the cable. These guards prevent any sharp bending of the cable ator near the point where the cable begins to become 00!!!- pacted, so that if the cable is subject to lateral bending or vibration it is not liable to become broken at the joint.

' Without exceeding the pressure easily obtainable with portable apparatus quite suitable for linework I can by my invention in a few minutes complete a splice on the largest feeder-cable manufactured.

Having described my invention, I claim 1. The method of splicing electrical cables, which consists in inclosing their ends in a ductile metal sleeve and then swaging down the sleeve into intimate contact with said ends and causing the metal of the sleeve to fill the external crevices of the cable.

2. The method of splicing electrical cables, which consists in inclosing their ends in a ductile metal sleeve and then swaging down the sleeve into intimate contact with said ends and thereby compacting the cable and eliminating its internal voids.

3. The method of' splicing electrical cables, which consists in inclosing their ends in a ductile-metal sleeve and then swaging down the sleeve into intimate contact with said ends and causing the metal of the sleeve to fill the external crevices of the cables and to produce on the contacting surfaces of the sleeve and the cables interlocking projections and depressions.

' 4. A splice for electrical cables consisting of cable-sections having their adjacent ends swaged' into a substantially-solid mass and an inclosing metal sleeve swaged into intimate contact with said ends.

.5. A splice for electrical cables consisting of cable-sections having their adjacent ends swaged into a substantially-solid mass and an inclosing metal sleeve swaged into intimate contact with saidends, the contacting surfaces of the cables and sleeve having swaged interlocking projections and depressions.

In testimony whereof I aflix my signature in presence of two witnesses.

I THOMAS J. MoTIGHE.

Witnesses: Tuos. A. CONNOLLY, Joe. B. CONNOLLY.

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