US2929862A

US2929862A - Compressible insulated connector for a shielded cable

Info

Publication number: US2929862A
Application number: US616526A
Authority: US
Inventors: Alan E Aune; Rocco J Noschese
Original assignee: Burndy Corp
Current assignee: FCI USA LLC
Priority date: 1956-10-17
Filing date: 1956-10-17
Publication date: 1960-03-22
Anticipated expiration: 1977-03-22

Description

March 22, 1960 A. E. AUNE ET AL 2,929,862

COMPRESSIBLE' INSULATED CONNECTOR FOR A SHIELDED CABLE Filed Oct. 17, 1956 INVENTORJ' 4/17/2 Tfll/zze J5 Un t S a s Pawfl COMPRESSIBLE INSULATED CONNECTOR FOR A SHIELDED CABLE Application October 17, 1956, Serial No. 616,526 2 Claims. (Cl. 174-75) This invention relates to a connector for terminating or grounding a shielded or coaxial cable.

Previous methods in use require a plurality of loose parts which are individually positioned on the cable in a specific sequence and finally adjusted and secured into a unitary connection. The sequence of installation was not always followed, the installation itself was time consuming, and the final results were uncertain.

Accordingly, among the objects of our invention is to provide a simpler, faster and surer method'for terminating or grounding one or more jumper or ground wires to shielded or coaxial cables; to provide a connection which is preinsulated, and compressible to secure all the connections simultaneously through the insulation; to providea ,means' for inspecting the final connection without the necessity of removing the insulation; and to provide a connection which the parts are factory assembled so that they may be applied as a unit to the conductors.

Further objects are to provide a connector having the foregoing characteristics which may be readily identified as to size and type, and which is inexpensive to manufacture by mass production techniques.

We accomplish these and other objects and obtain our new results as will be apparent from the device described in the following specification, particularly pointed out in the claims, and illustrated in the accompanying drawing, in' which:

Fig. 1 is a perspective view of the completed connection.

Fig. 2 is a perspective, partially longitudinally sectioned view of the connector before assembling, with the con ductors in exploded position.

Fig. 3 is a longitudinally sectioned view of the assembled connectors.

The connector comprises a metal barrel 12, and an insulating cover 14. The barrel is made by closing one end of an inner ferrule 16 and an outer sleeve 18, respectively, by a connecting wall 20, into which is formed one or more holes 22. The inner ferrule contains the hollow portion 24 for passing the insulated conductor 26 therethrough, and between ferrule 16 and sleeve 18 is the annular hollow portion 28 into which the braided wire 30 of the shielded or coaxial cable 32 is inserted.

The outer sleeve 18 tapers conically from the mouth in the direction of the closed end wall 20 and towards the inner ferrule 16. This permits the braided cable 30, as well as the bared end 34 of the ground or jumper lead 35, to be easily inserted into the correct position for crimping. The taper also minimizes the distance that the outer sleeve 18 has to be collapsed to form a good crimp. A bulge 36 is formed in the outer sleeve adjacent each hole 22 to permit larger holes to be formed without enlarging the entire periphery of the outer sleeve. These holes permit the connection to be inspected and also serve as entrances for the ground or jumper leads if a change of direction of entrance is considered more desirable.

The inner ferrule is longer than the outer sleeve so through the holes 22.

that the braided wire shield can be first applied over the inner ferrule, facilitating passage under the outer sleeve thereafter. The edges of the ferrule and sleeve are made smooth to make such entrance easier.

The insulation cover is of tubular construction, and is made of suitable plastic which can transmit a crimping force without damage thereto, as is shown in the Rogoff Patent 2,429,585. Certain nylon compositions may also beused. The insulation cover is preferably formed separately from the metal barrel 12. The plastic being slightly springy, permits sufficient resilient deformation to permit the metal barrel to be inserted at the flared end 38 over peripherally formed shoulder 40 until it engages the stop shoulder 42. Shoulder 40 upon the edge 44 of outer sleeve to form a stop, prevent-- ing accidental separation of the two parts.

or other suitable material, such as copper, on an eyelet ting machine.

[The insulation cover may be stamped or molded to? provide a better designation, as well as being color coded, making positive size and type identification easier than in pro-existing devices.

The assembly procedure is as follows:

The shield insulation 46 is removed for the correct distance. The braided shield or conductor 30 is then stripped back for the necessary distance, exposing the insulated conductor. around in an arc to flare out the end of the braid, as shown in Fig. 2. The conductor is then inserted into the hollow of the ferrule with the braided shield entering the annular space, until the end of the braid is seen The connector is slowly revolved during the process of insertion to prevent the strands of the braid from bunching. At this point, the shield insulation 46 should be well under the insulating cover 14.

The jumper lead is then inserted into the hollow portion 28, making certain that the strands of the braid are undisturbed, and that the conductor 34 is not exposed.

The assembly is then crimped, as at 48, using preferably a circumferential crimping tool which will cause intermeshing groove indentations, preserving a substantially circular cross-section when reduced by the compression.

The compression tool is designed to compress the insulation cover and outer sleeve upon the inner ferrule. The barrel may be formed so that the outer sleeve is softer than the inner ferrule to facilitate collapse on the inner ferrule. Alternatively, the inner barrel may be made thicker to resist collapse when the outer sleeve is crimped.

The pre-insulated connector just described provides a compact, simple device for joining ground or jumper wire to shielded or coaxial cable.

to remove the insulation.

then springs back The

shoulders

40 and 42 are outwardly chamfered to minimize snagging of the wire braid and connecting conductors when in- The conductor is then swung.

The taper of the outer sleeve results in a large opening for the insertion of the wire braid and for any ground or jumper wires; At the same time, the taper minimizes the distance that the barrel has to be deformed to give the crimp pressure needed to secure the installation.

The bulge around the peep holes allows for a larger opening than would ordinarily be possible for the insertion of ground or jumper wires. This is accomplished without interfering with the function of the taper design of the sleeve.

The longer inner ferrule simplifies the assembly operation to the coaxial or shielded cable, by making it possible to first insert the inner ferrule portion under the wire braid before the outer ferrule passes over the wire braid. This minimizes the possibility of any individual strands of the wire braid from becoming snagged at the mouth of the connector.

The chamfer built into the inner shoulders minimizes the snagging of the wire braid at the mouth by providing an uninterrupted transition from the larger opening of the barrel.

The pre-assembled insulating cover provides a means acaasea to employ all equivalent instrumentalities coming within the scope'of the appended claims, and by means of which, objects of our invention are attained and new results accomplished, as it is obvious that the particular embodiments herein shown and described are only some of the many that can be employed to attain these objects and accomplish these results.

1 We claim: a

1. An electrical cable connector for securing a connection to a cable having a shield which comprises an inner metal ferrule, an outersconcentric positioned metal sleeve having the inherent physical characteristic of being l more soft than said ferrule, said ferrule and sleeve formed for lettering each connector with its size designation,sin- 7 addition to providing a better method of color identificai n.

because only one piece need be handled instead of. the many hitherto required. 7 The circumferential type of compression secures the insulating cover to the outer portion of the barrel, and at the same time reduces the diameter of the outer portion of the barrel, thereby compressing the braid and grounding lead (if used) between the outer and inner out in other ways without departing from the spirit of ur inven ion, and, th refor e claim b oa y the, ight The connector provides a lower installed cost of malt-I ing terminations or grounding coaxial .or shielded cable of a single piece of metal, the free edge of said sleeve lying in a single plane, and an insulating cover for said outer sleeve, said ferrule, sleeve, and cover secured into a unitary assembly having a hollow portion in the ferrule for inserting said cable, a space between said ferrule and sleeve for containing the shield of said cable, said sleeve and cover being collapsible to permit a conductor inserted between the inner metal ferrule and sleeve to be electrically and mechanically joined to the connector and;

shield of said cable.

2. The connector of claim 1, wherein the ferrule ex tends longitudinally for a greater distance than the sleeve and the cover extends longitudinally for a greater dis;

tance than the ferrule.

References Cited in the file of this patent.

OTHER REFERENCES Publication 1, Grounding Shielded Cables '(Manzt et' fial.), published in Electrical Manufacturing, December 1952. (Pages 128-130 relied on.)