US3737840A

US3737840A - Lug assembly

Info

Publication number: US3737840A
Application number: US00200963A
Authority: US
Inventors: N Hoffman
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1971-11-22
Filing date: 1971-11-22
Publication date: 1973-06-05
Anticipated expiration: 1990-06-05

Abstract

This invention relates to a lug assembly and more particularly to a bar having one or more tapered passageways therein to receive a partly deformable connector in which is emplaced the end of a cable to be joined to the lug assembly. Further this invention relates to a tool for inserting the connector into the bar as well as for removing the same therefrom.

Description

[ 1 June5, 1973 United States Patent 1 Hoffman 3,235,944 2/1966 Broske et al. .....................339/271 l Hap 1,535,117 4/1925 Fulton ct nl.......................339/273 R [54] LUG ASSEMBLY [75] lnventor:

FOREIGN PATENTS OR APPLICATIONS 366,315 2/1963 Switzerland ......................339/273 R Primary Examiner.loseph H. McGlynn Attorney-William .l. Keating, Gerald K. Kita, John K. Flanagan and Allan B. Osborne et al.

Nov. 22, 1971 [2]] Appl. No.: 200,963

d m W 6 mm m mo m .W

r mo 6 e T fin C 30 A g R u T In S mm B t h A m d 0 .mm l m... ism 7 i he 5 .1 TI

IHZI

F mm a m m Umm passageways therein to receive a partly deformable [56] References cued connector in which is emplaced the end of a cable to UNITED STATES PATENTS be joined to the lug assembly. Further this invention 3,588,791 6/1971 P0lid0ri.............................

relates to a tool for inserting the connector into the bar as well as for removing the same therefrom.

339/273 R 2 Claims, 13 Drawing Figures 3,624,591 11/1971 Bubermiak........... 2,147,239 2/1939 Buchanan PATENTEB 57975 manor-3 LUG ASSEMBLY BACKGROUND OF THE INVENTION Lugs which connect one or more electrical power lines to a pad mounted transformer are well known in the art. Such lugs generallyare flat aluminum plate attachable at one end to the transformer and having a number of holes on the other end to permit the attachment of a terminal thereto via bolts or the like. While such attachment is entirely satisfactory from both a mechanical and an electrical viewpoint, it does require a terminal to be first affixed to the cable by soldering, crimping or other ways. Where large numbers of cables are being so attached, the current method above described involves considerable time and expense.

Accordingly, the present invention provides a lug assembly for retaining at least one cable which comprises at least one connector which contains a bore adapted to receive a cable and a bar having at least one passageway adapted to removably receive the connector and retaining means in the passageway and on the connector cooperating to retain the cable in the connector and removably retain the connector in the passageway.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings and to FIG. 1 in particular, shown therein and generally designated by the reference numeral is the lug assembly constructed in accordance with the invention. The basic member of lug 10 is bar 12 which may be made of 6063 aluminum and suitably heat treated. Contained within bar 12 are two identical passageways both designated at 14. Each passageway 14 has four inwardly facing, C-shaped grooves, collectively designated at 18, spaced equidistant one from the other about the periphery of the passageway. The passageway itself is defined by four longitudinally tapered lands collectively designated at 20. The taper increases toward the side of the bar away from the reader. Lands 20 are also transversely curved, each having the same degree of curvature.

Positioned in the left passageway 14 is the cable housing or connector 22 and cable 24, the two when joined being hereinafter designated as sub-assembly 25 (see for example FIG. 6a). Such sub-assembly is retained in bar 12 by cooperative action of passageway 14 and connector 22 as will be discussed below.

There is provided on the right hand side of bar 12 a threaded aperture (not shown) which receives a bushing or other like connections as may be applicable.

A series of horizontal slots 23 are provided on the side of bar 12 facing away from the reader (see FIG. 5). Slots 23 are for the purpose of aligning bar 12 with the applicator tool (FIG. 3) during assembly of lug 10.

facing, tapered, curved surface 34. Webs 26 and jaws 32 define longitudinal bore 36 extending through connector 22. l

Referring now to FIGS. 3a and 3b, shown therein and generally designated by reference numeral 40 is a preferred embodiment of the assembly tool useful for mounting sub-assembly 25 into bar 12. Tool 40 includes a C-shaped frame 42, a mandrel unit 44 and an engaging section 46. Engaging section 46 consists of two parallel, spaced apart arms, both designated at 48, and a pin 50 positioned midway up each arm and facing inwardly toward mandrel unit 44. At the base of arms 48 a transverse cavity 52 is provided for receiving the bottom edge of bar 12 during assembly. Such cavity extends normally across frame 42.

Mandrel unit 44 includes arm 54 having an internally threaded bore 56 which accommodates a conventional thread unit 58. Unit 58 in turn rotatably receives mandrel 60 which contains, on its forward end, ram 62 having cavity 63 therein. Ram 62 is swively mounted to have freedom of rotational motion independent of mandrel 60. The back end of mandrel 60 is formed into a hexagonal projection 64 to accomodate means (not shown) to rotate the mandrel.

FIG. 4 illustrates the take-off attachment 66 to tool 40. Attachment 66 consists of top and

bottom units

68 and 70 respectively and ram adapter 72.

Units

68 and 70 have

slots

74 and 76 respectively on one side and

fingers

78 and 80 respectively on the opposite side. Ram adapter 72 is cylindrical in shape and has recesses 82 and 84 in opposite ends thereof.

OPERATION OF THE PREFERRED EMBODIMENT With reference to FIGS. 5 thru 9b, the operation of the preferred embodiment will be described; FIG. 5 showing the alignment of connector 22 and cable 24 with bar 12 prior to assembly.

Connector 22 is inserted into passageway 14 in bar 12 with each groove 18 receiving a web 26 as seen in FIG. 6a. The sub-assembly is hand-pressed into passageway 14 until interference between tapered lands 20 and tapered surfaces 34 on jaws 32 prevents further such insertion.

Assembly tool 40 is now positioned on bar 12 as seen in FIG. 7. Pins 50 engage the slots thereon so as to align ram 62 on mandrel 60 with connector 22 in bar 12. The

' aforementioned groove 52 accommodates the edge of bar 12 so as to prevent interference in positioning the bar against arms 48 and frame 42 and also to prevent a source of stress concentration which is present whenever a sharp corner engages a solid surface. Cable 24 is passed thru passageway 14 and thru bore 36 of connector 22 to form aforementioned subassembly 25. As is shown in the drawings and as is well known in the art, that part of cable 24 which engages connector 22 has its insulation removed where, as shown here, an electrical as well as a mechanical attachment is to be made.

The relationship between connector 22 and cable 24 at this point is shown in FIG. 6a. Note that cable 24 does not necessarily engage the walls of bore 36.

That portion of cable 24 projecting beyond connector 22 is received within cavity 63 in ram 62 so as to permit flush engagement of the ram with the face of the jaws of the connector. Mandre'l 60 is then rotated, driving subassembly 25 deeper into passageway 14 as shown in FIGS. 8 and 9b. As the diameter of lands 20 within passageway 14 decrease due to the taper thereon, jaws 32 are forced radially inwardly. As the jaws are forced inwardly, the integrity of connector 22 is preserved by legs 28 of webs 26 drawing intoward each other. This novel feature can be seen by comparing FIGS. 60 and 9a. Note in FIG. 9a that jaws 32 have been squeezed onto cable 24 and that legs 28 have been drawn together as a result of the jaws being forced inwardly. As the connector is softer than either the bar or cable, it is compressed tightly against the entire circumference of the cable and also against the tapered surface of lands 20 without deforming or damaging either the cable or bar.

Removing sub-assembly 25 from bar 12 is as uncomplicated as the assembly described above. The bottom unit '70 of take'off attachment 66 is installed on engaging section 46 by sliding the unit onto arms 48 via slots 76 so that fingers 80 projecttoward ram adapter 72 which had been placed onto ram 62 via recess 82. Bar 12 is then placed onto frame 42 so that fingers 80 abutt the two lower webs 26 on connector 22. The top unit 68 of take-off attachment 66 is next emplaced on section 46 over bottom unit 70 with cable 24 thereinbetween. Fingers 78 abutt the two upper webs 26 on connector 22. FIG. 10 shows the completed assembly for removing sub-assembly 25 from the bar 12. Note that the portion of adapter 72 defining recess 84 abutt against bar 12 and that recess 84 is aligned with passageway 14. I

By rotating mandrel 60, bar 12 is driven toward arms 48 on frame 42. Connector 22, abutting

fingers

78 and 80, is forced back out of passageway 14.

If sub-assembly 25 is to be replaced into bar 12, the procedure described above is repeated. In this case sub-assembly 25 will be driven alittle deeper into passageway 14 due to the previous crimping of jaws 32 on connector 22.

If sub-assembly 25 is to be disassembled, it will be necessary to cut or pry connector 22 off cable 24 because of its grip on the cable.

In addition to the novel and advantageous features described above and apparent from the drawings in conjunction with such description, a lug assembly of a given dimension, constructed in accordance with the present invention, is capable of connecting a wide range of cable sizes. For example, one prototype so constructed successfully connected electric power lines ranging in size from l/O to 4/0. Further, this range can be extended by changing either the depth of passageways 14, the taper of lands 20, the bore 36 in connector 22 or a combination thereof.

Yet another feature of the present invention is the economical method of producing connector 22.-A continuous ingot is forced thru a form-imparting die and thereafter cut to a desired length. The jaws on the connector are then impacted to form the tapered and curved surface. During this latter process, the surface area of each jaw is increased which increases conductivity between the connector and bar 12.

One type of aluminum alloy has been mentioned as a suitable material to use in fabricating lug 10. As is well known in the art, other materials may be used. For example, a die casting alloy such as 360 aluminum has been found to be suitable.

The present invention has been described as such relates to connecting power lines to the secondary side of a pad mounted transformer. However, such description should not be considered as limiting the invention thereto. As the advantages of this invention become known, other and different uses will become evident. For example, the present invention will be useful wherever it is desirable to securely fasten wire rope or cable to a structure. Not only is a minimum amount of preparation required, but equipment such as U-bolts, hooks and the like are unnecessary.

It is intended that the particular embodiment of the invention shown and described herein is merely illustrative and the spirit and scope of the invention is limited only by the appended claims.

What is claimed is:

1. A lug assembly for retaining a cable which comprises:

a connector having two deformable webs and two jaws having tapered surfaces, each of said jaws positioned between and integrally attached to said webs, said webs and said jaws defining a bore adapted to receive said cable; and a bar having a passageway, said passageway being defined by two grooves and two lands having tapered surfaces, each of said lands positioned between said two grooves, said passageway adapted to removably receive said cable-bearing connector, said grooves receiving said webs and said lands receiving said jaws and causing said jaws to be depressed radially inwardly.

2. The connector of claim 1 wherein each of said at least two webs include two outwardly converging legs, each leg attached to a side of said jaw and being joined at a point removed therefrom.

Claims

1. A lug assembly for retaining a cable which comprises: a connector having two deformable webs and two jaws having tapered surfaces, each of said jaws positioned between and integrally attached to said webs, said webs and said jaws defining a bore adapted to receive said cable; and a bar having a passageway, said passageway being defined by two grooves and two lands having tapered surfaces, each of said lands positioned between said two grooves, said passageway adapted to removably receive said cable-bearing connector, said grooves receiving said webs and said lands receiving said jaws and causing said jaws to be depressed radially inwardly.