US 3280246 A
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Description (OCR text may contain errors)
Cet. 18, 1966 R, LAWSON ET AL 3,280,246
GROUND SHEATH CONNECTOR Filed Feb. 2, 1965 INVENTORS.
, M z 5 24 GUSTAF R. LA WSoN Z 7" Z0 rlvllll; 32 M A\\\\wy United States Patent C 3,280,246 GROUND SHEATH CONNECTOR Gustaf R. Lawson, Somerset, and William M. Hawkins, Scotch Plains, NJ., assignors to The yIhomas Betts Co., Elizabeth, NJ., a corporation of New Jersey Filed Feb. 2, 1965, Ser. No. 429,837 3 Claims. (Cl. 174-88) The invention relates to electric cables generally and to a method of and apparatus for grounding cables of the kind in which a plurality of wire conductors, arranged in insulated bunched parallelism, are individually shielded against high frequency currents by means of a braided metallic covering or shield on each conductor.
More particularly, the invention relates to a grounding sheath connector adapted for collectively, grounding individually, shielded, insulated wire conductors assembled in cable formation whereby the high frequency shielding on the conductors may be readily connected as a group, indirectly to ground through an attached auxiliary conductor without adversely affecting the shielding on such conductors, the cable structure or its electrical characteristics.
Similar grounding sheath connectors as used heretofore, possessed certain disadvantages in that the outer annular member thereof, when reduced to iin-al diameter on and relative to the inner annular member, with a plurality of braided metallic shield free end portions arranged circumferentially therebetween, not only placed objectionable stress upon the shielding in direct metal to metal Contact with the inner periphery of the inner yannular member, but also tended to abrade, cut into or other- Wise damage the metallic shielding under the connector upon relative movement thereof, as a unit, on a plurality of bunched, parallel, individually shielded, insulated wire conductors.
Accordingly, it is an object of the invention to provide a ground sheath connector for a plurality of individually shielded, insulated wire conductors, arranged in bunched parallelism, which obviates the above noted disadvantages.
A further object of the invention is to provide a ground sheath connector of the character described which is adapted to be mounted in insulated, yieldable relation on and about a plurality of individually shielded wire conductors arranged in bunched parallelism.
Another object of the invention is to provide a ground sheath connector of the character described which will not abrade or otherwise. injure braided metallic shielding on each of a plurality of wire conductors, arranged in bunched parallelism, when mounted thereon.
A further object of the invention is to provide a ground sheath connector of the character described wherein the outer annular member includes a pressure transmitting sleeve, layer or coating on its outer periphery whereby the diameter thereof may be reduced or diminished by a cold swaging operation on and relative to the diameter of its inner annular member in response to a suitable squeeze pressure thereon, without buckling or deformation of the circular contour of the outer 4annular member.
Another object of the invention is to provide a ground sheath connector of the character described which obviates the wrapping of tape or the like or, placing a section of plastic tubing over and about a plurality of individually shielded wire conductors arranged in bunched parallelism prior to mounting the ground sheath connector thereon.
A further object of the invention is to provide a ground sheath connector as described which is adapted to resist endwise and angular movement of the connector relative to a plurality of individually shielded conductors arranged in bunched parallelism, when disposed on and about the bunched conductors.
Another object of the invention is to provide a ground sheath connector as described which is adapted to resist and/ or absorb squeeze pressure when imposed indirectly on the bunched, individually sheathed Wire conductors, during the operation of mounting the connector in collectively grounded relation thereon.
With the above and other objects in view, the invention resides in the novel construction, combination and arrangement of parts, the novel features of which are set forth with particularity in the appended claims, the invention itself, however, both as to its organization and method of operation, together with additional objects and advantages thereof, being best understood from the following description of a specific embodiment thereof, when taken in connection with the accompanying drawing in which:
FIGURE l is a perspective view showing the invention as mounted on and about a plurality of bunched, parallel, individually shielded wire conductors in collectively grounded relation thereto, including a ground Wire leading therefrom;
FIGURE 2 is an exploded view in perspective illustrating the manner of placing a free end portion of the shielding on each of a plurality of wire conductors, arranged in bunched parallelism, on and about the inner annular member of the grounding connector, after the said inner member has been placed thereon, preparatory to fitting the outer annular member of the connector thereover;
FIGURE 3 is a fragmentary view in perspective of a section of Ia shielded Wire conductor illustrating the removal of an end portion of the shielding therefrom for the purpose set forth;
FIGURE 4 is an exploded view in perspective, illustrating how the stripped end portions of the shielding on the wire conductors in the middle or center of a bunched bundle lof conductors are passed through the inner annular member of the ground sheath connector and then laid or folded over the outer periphery thereof preparatory to fitting the outer annular member of the connector thereover, and the final squeeze pressure reduction or cold swaging of its diameter on the stripped, angularly disposed shield end portions;
FIGURE 5 is a sectional view through the ground sheath connector mounted on a plurality of bunched, parallel individually shielded conductors;
FIGURE 6 is a sectional view of the two-piece annular ground sheath connector showing the non-metallic cushion or vinyl coating on the inner periphery of the inner annular member, and the yieldable plastic coating or layer on the outer periphery of the outer annular member;
FIGURE 7 is a fragmentary sectional view of a modified form of the ground sheath connector; and
FIGURE 8 is a perspective view illustrating a pair of complementary die members as utilized to cold swage the outer -annular member of the connector unit on the foldedover shield end portions to provide a collective ground connection.
Referring to the drawing, FIGURE l illustrates the impr-oved ground yshield connector 10 as assembled on a plurality of individually shielded, insulated wire conductors 12, arranged in bunched parallelism with a ground wire 14, common thereto, leading from the connector unit lil, and one end portion ofthe shielded wire conductors 12 terminating in a conventional multiple pin plug 16.
In accordance with the invention and `as best shown in FIGURES 2, 3, 4, 5, 6 and 7, the ground sheath connector 10 comprises 4an inner annular member vor collector ring 18 0f tinned brass, for example, and an outer annular member or compression ring 20 of tinned soft copper, for example, having a 'larger diameter than the linner collecting ring 18. As shown in several of the drawing figures, the collector ring 18 -is provided on its inner periphery and opposite end faces with a substantial coatin-g 22 of any one of several well known yieldable compounds such as PlastisoL for example, suitably bonded thereto, to provide a cushion facing thereon having a thickness inthe ran-ge of ten thousandths to oneeighth of an inch depending on the diameter or size thereof.
The outer compression ring 20 is also provided on its outer periphery -with a bonded coating, 4layer or sleevelike covering 24,*lof a yieldable, rubber-like plastic compound for the purpose described las well as an insulating medium for the entire connector assembly whereby when the metallic rings'or bands 18 and 20 have been assembled in free telescopic -relation on a bundle of individually shielded wire conductors 12, with a stripped end portion 26 of the shielding lon each of the wire conductors 12, disposed therebetween, the compression ring 20 is cold swaged over the relatively hard collector ring 18, lby means of a suitable two-part die 28, to clinch .the shield end portions 2,6 in approved conductive relation therebetween including the ground wire 14, common thereto and leading from the connector unit 10.
It is to Ibe observed that the coating or covering 24 integral with the outer compression ring 20, as above de'- scribed, is also adapted toinsulate the entire connector unit 10, after the assembly lthere-of cn a plurality of individually shielded, insulated conductors arranged in bunched parallelism.
With particular reference to FIGURE 2, it will -be observed that the stripped end portion 26, of the braided metallic shielding on each of the wire conductors 12, whether it be located in the center of t-he bundle thereoct or adjacent its outer periphery, is folded over on the bare, outer periphery of the collector ring 18, in angularly spaced relation, the angular positioning thereof being accomplished in such manner that all of the foldedover end portions 26 are superposed evenly about the bare periphery of the collector ring 18, whereby the positioning of the compression ring 20 thereover is facilitated.
The outer periphery of the compression ring 20` may also be coated with la yieldable plastic suitably bonded thereon by masking the inner periphery of the ring 20 and dipping the same in a yieldable compound until a sufliciently dense coating has been deposited thereon. Thus, it is to be understood that their collector ring 18, as well as the compression r-ing 20, may be selectively coated with the compound by la dipping or spraying operation.
In Ianother [form of the invention, the yieldable coating 22 on the inner periphery of the collector ring 18 is dispensed with and the ring 18 circumferentially seated on a sleeve or collar 30 of molded nylon having a shallow annular groove in the periphery thereof for receiving the ring 18 .in slip-iit fashion thereon, the wall thickness of Ithe annular groove in the nylon -sleeve 30, between its end faces, being substantially equal to the thickness of the collector ring 18, and the end margins of the sleeve 30 lbeing of a diameter just suicient to provide shoulders 32 for the retention of the ring 18 on the nylon sleeve 30.
While the invention has been illustrated and described with respect to one embodiment thereof, it is to be expressly understood that various changes and modifications may be made therein without departing from the inventive concept underlying the same. Therefore, the :herein described invention is not to be limited except as is necessitated by the prior art and the scope of the appended claims.
What is claimed is:
1. A ground sheath connector comprising a conductive collector ring, ya plurality lof hunched, parallel, individually shielded wire conductors passing within said collector ring, a stripped end portion of the shielding on eac-h conductor llying on and in contact with the outer periphery of the collector ring, the inner periphery of said collector ring being covered with a yieldable, plastic insulation material, a larger diameter complementary compression ring of relatively soft conductive metal assembled in telescoping relationship over the collector ring and the stripped end portions of the shielding, -sa-id compression ring being in 'contact with said stripped end portions, and a ground wire in electrical contact with said compression ring, said compression ring being adapted to be cold swaged on -said collector rin-g in response to squeeze pressure thereon.
2. A connector as defined in claim 1 wherein said compression ring has a covering on it-s louter periphery Aot yieldable pressure transmitting plastic.
3. A connector las defined in claim 1 wherein said plastic insulation material is in the form of an annular Vgrooved nylon sleeve, said collector ring received in said groove.
References Cited by the Examiner UNITED STATES PATENTS 2,342,958 2/ 1944 Morehouse. 3,123,663 3/ 1964 Muldoon 174-90 X 3,145,261 8/ 1964 Forney 174-84 OTHER REFERENCES March: Ferrules Shield Multiconductor Cables, Electronics, pub. 9/25/59, page 98.
LEWIS H. MYERS, Primary Examiner.
DARRELL L. CLAY, Examiner.