US3259981A - Method of joining together a terminal connector and an electric cable - Google Patents

Description

July 12, 1966 E. B. RAYMOND ETAL 3,259,981

METHOD OF JOINING TOGETHER A TERMINAL CONNECTOR AND AN ELECTRIC CABLE Filed Nov. 19. 1963 I 2; 5 M 1 7% 2 1 IN ENTOREI Egan E 74/440447 .4 A554 /5 1, Jaw/445R United States Patent 3,259,981 METHOD OF JOINING TOGETHER A TERMINAL CONNECTOR AND AN ELECTRIC CABLE Eugene B. Raymond, Skokie, and Leslie L. Schiller, Niles,

IlL, assignors to Triple A Specialty Co., Chicago, Ill.,

a corporation of Illinois Filed Nov. 19, 1963, Ser. No. 324,673 1 Claim. (Cl. 30-289) Our invention relates to a new and improved method of joining together a terminal connector and an electric cable having a conductor core encased by insulation so as to provide positive contact between the connector and the cable to prevent withdrawal of the cable from the connector.

Prior to our invention it was the common practice in the art of terminal connectors used for connecting a terminal cable electrode of a sparkplug, to provide in the connector a prong which was driven into the insulation of the cable to pierce the electrical conductor core thereof. It was also a common practice to provide a terminal connector with a prong which was driven int-o the end of the terminal cable to contact the core thereof.

With the requirement that terminal cables used in connection with internal combustion engines be formed of radio-resistant material, these known methods of joining a terminal connector to the end portion of a terminal cable have proven unsatisfactory. This resulted from the fact that in certain instances the prong driven into the cable either from the side or from the end thereof, would cut or otherwise damage or rupture the conductor core, thus forming a weak or defective contact between the terminal connector and the conductor core of the cable. Our improved method has for its principal object the elimination of these and other known defects of the prior art methods of joining a terminal connector to a conductor core.

Other objects will appear hereinafter.

The invention consists in the novel method and embodiment of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawings, in which:

FIG. 1 is a plan view of a notching tool;

FIG. 2 is a side elevational view of the same;

FIG. 3 is a fragmentary side view of an electrical cable;

FIG. 4 is a side view of the end portion of the electrical cable shown in FIG. 3, showing a part of the insulation thereof notched out;

FIG. 5 is a fragmentary sectional detail view showing the terminal connector and cable connected together by our improved method;

FIG. 6 is a plan view of a blank from which our connection is formed;

FIGS. 7 and 8 diagrammatically illustrate dies for forming certain parts of our connector.

In carrying our improved method into effect, we form in the terminal cable 10 a notch 11. This notch 11 extends transversely and inwardly from the end portion 12 of the cable 10 and is of a depth to expose at 13 a surface portion of the electrical conductor 14. This electrical conductor in the present instance comprises a plurality of non-conductive thread-like strands 15 which may be formed of any suitable material, such, for example, fiber glass. These strands are encased in a conductive coating 16 of any suitable material, such, for example, carbon. The conductor core 14 is then encased in an insulating material 17 which is notched to provide the notch 11 hereinbefore referred to.

The notch 11 may be formed by any suitable notching tool, such, for example, as shown in FIGS. 1 and 2. In this connection, the tool comprises a pair of handle members 18 and 19 connected together in scissors fashion by a bolt or pivot 20. The handle member 19 is channelshaped in cross section and at one end thereof is provided an elongated slot 19' through which the end portion 18 of the handle member 18 projects.

The handle member 19 has a transverse elongated tubular holder 21 provided with a circumferential slot 22 on one side of its long axis. The handle member 18 provides a cutting tip 23 which passes through the slot 22 when the handle members 18 and 19 are pivoted toward each other by grasping the portions 29 thereof.

The end of the cable to be notched is positioned in the tubular holder 21. The handle members 18 and 19 are pivoted to bring the cutting tip 23 into cutting relationship with the cable 10. This operation provides the notch 11 which extends transversely of the cable 10 a suitable distance from the adiacent end of the cable and is of a depth sufficient to expose the surface portion 13 of the core 14.

After the notching operation a conductive connector C is attached to the notched end nortion of the cable. From one end portion of a blank 24' an open ferrule 24 is formed. Struck therefrom. from the bottom wall the reof, is an elongated relatively flat transversely extending contact plate 25. The forming of the ferrule 24 and the striking therefrom of the contact plate 25 is accomplished by dies D diagrammatically illustrated in FIG. 7.

The notched end portion of the cable is placed in the open ferrule with the contact plate projecting into the notch in positive contact with the exposed portion of the core 14. After the nitched end portion of the cable is thus placed in the open ferrule, the side walls 26' thereof are folded inwardly upon the cable forming, together with the ferrule, a sleeve clampingly embracing the notched end portion of the cable thereby to fixedly secure the contact plate in the notch in pressing contact with the exposed surface of the core. The folding of the side walls of the ferrule upon the cable may be accomplished by any suitable forming dies such as are illustrated in FIG. 8, at E.

The connector C is more fully disclosed in our copending application filed on even date hereof, and bearing Serial No. 324,711.

When the terminal connector C is connected to the cable 10 by our improved method, the contact plate 25 cooperates with the notched-out portion 11 of the cable to prevent withdrawal of the notched end portion of the cable from the ferrule 24.

In disconnecting the sleeve 27 from the electrode of a sparkplug 28, one invariably grasps the cable 10 and pulls in a direction to accomplish such disconnection. This pulling on the cable in the methods of the prior art hereinbefore described, generally results in a breaking of the contact between the connector and the core of the cable, or the disconnection of the cable from the terminal connector. By our improved method this cannot take place because of the cooperation of the contact plate 25 and the notch 11 in the cable 10.

The various advantages and objects of the invention may be accomplished by modifications of the particular method and embodiment specifically described herein, and it is intended that the appended claim shall include all equivalent arrangements and methods coming within their call.

Having thus described our invention, what we claim as new and desire to protect by Letters Patent is:

A tool for notching a portion from the side of an insulated terminal cable to expose the electrical conductor core thereof, comprising (a) a pair of handle members pivotally connected together inwardly of corresponding end portions thereof,

(b) a holder for said cable comprising a sleeve formed integrally with an end portion of one of said members and extending transversely of the long axis of said one member,

(0) said sleeve having a slot formed in one side thereof in a circumferential direction with respect to said sleeve,

(d) and a cutting tip formed on an end portion of the other of said members and movable into said slot through an are passing through the insulation of said cable on one side of the long axis of the cable for notching out a side portion of said cable to expose the conductor core therein.

References Cited by the Examiner UNITED STATES PATENTS EDWARD C. ALLEN, Primary Examiner.

JAMES L. JONES, ]R., Examiner.

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