US3923363A

US3923363A - Hot line connector

Info

Publication number: US3923363A
Application number: US497894A
Authority: US
Inventors: Russell H Kraft
Original assignee: Fargo Mfg Co Inc
Current assignee: Fargo Mfg Co Inc
Priority date: 1974-08-16
Filing date: 1974-08-16
Publication date: 1975-12-02
Anticipated expiration: 1992-12-02
Also published as: CA1017018A

Abstract

A hot line connector for firmly attaching a tap-off conductor to a high voltage line in which there are clamping jaws with an improved interposed spacer having insulation piercing teeth adapted to pierce insulation and make flat contact with line to insure full mechanical contact, adequate electrical connection between the line and the conductor.

Description

United States Patent 1 91 1111 3,923,363

Kraft 1 Dec. 2, 1975 15 1 HOT LINE CONNECTOR 3,132,914 5/1964 Wengen 339/109 3,425,028 l/l969 Neaderland.... 339/95 R [75] mentor: Kraft HPewel1 3,426,319 2/1969 Downs et al. 339/272 R Juncflon 3,760,341 9/1973 Grad 339/272 R [73] Assignee: Fargo Mfg. Company, Inc.,

Poughkeepsie, NY. Primary Examiner loseph H. McGlynn [22] Filed: Aug. 16, 1974 1 1 pp 497,894 57 ABSTRACT A hot line connector for firmly attaching a tap-off ?g gZ conductor to a high voltage line in which there are Fieid "55 97 99 clamping jaws with an improved interposed spacer 264 having insulation piercing teeth adapted to pierce insulation and make flat contact with line to insure full mechanical contact, adequate electrical connection [56] uNlTEg g a A g gs gzfrENTs between the line and the conductor.

2,096,796 10/1937 Dunaway .7 339/109 1 Claim, 7 Drawing Figures "m ll U.S. Patant Dec. 2, 1975 Sheet 1 of 4 3,923,363

U.S. Patent Dec. 2, 1975 Sheet 2 of4 3,923,363

US. Patent Dec. 2, 1975 Sheet 3 (f4 3,923,363

FIG. 5

Sheet 4 of 4 3,923,363

Patent Dec. 2, 1975 HOT LINE CONNECTOR BACKGROUND OF THE INVENTION This invention relates to a functionally and structurally improved connector assembly intended to connect tap-off conductors with transmission lines.

Pat. No. 3,132,914 describes and claims a clamp assembly of the type described and claimed herein. The connector of the present invention embodies improvements to the clamp assembly of that patent including two ring type clamps for firmly securing the tap conductor to the lower jaw, an elastic removable band for detachably holding the spacer bar to the connector assembly, and insulation piercing teeth embedded in the spacer bar adapted to pierce the insulation and mushroom against the metal conductor for a full contact electrical connection.

SUMMARY OF THE INVENTION It is a primary object of the invention to provide an assembly in which the tap-off conductor may be firmly secured to permanent parts thereof in a manner such that the linesman need not fear that an accidental uncoupling of the tap-off will occur at the time he is manipulating the assembly to associate it with a hot or transmission line; the conductor remaining as a permanent part of the assembly throughout the entire life of the latter.

A further object is that of providing an assembly which may readily be manipulated by the linesman and which may be manufactured at nominal cost.

Moreover, by the present teachings, a structure is furnished such that the clamp may readily be electrically connected with or disconnected from a transmission line without danger of damage to the latter incident to arcing or similar causes.

It is a further object to provide an assembly in which insulation piercing teeth are embodied within the assembly to pierce the insulation and mushroom against the metal line to insure a full contact, adquate electrical connection between the transmission line and the tap-off conductor.

It is a further object to provide an assembly in which a spacer bar is readily detachable from the assembly to permit such bar, when locked to the transmission line, to be re-connected to a connector assembly.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects and advantages will become apparent from the following description which is to be taken in conjunction with the accompanying drawings, in which:

FIG. 1 is an exploded or separated view of the connector of the present invention showing the various components;

FIG. 2 is a rear elevation of the connector in applied position;

FIG. 3 is a top view;

FIG. 4 is a front view;

FIG. 5 is a side view;

FIG. 6 is a front view, partly broken away and in section, showing a modified type of connector with additional insulation piercing teeth;

FIG. 7 is a sectional view taken along the line 77 of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, in FIG. 2 the reference numeral 10 indicated a hot or transmission line and 11 one form of the tap-off conductor. As shown especially in FIG. 1, the assembly will include a main clamp involving an upper jaw 12 and a lower jaw 13. These jaws are disposed in opposed relationship and are maintained in this position by conveniently providing as part of the lower jaw a rearwardly extending casing portion 14 the interior of which defines in plan a rectangular space. Within that space a block 15 is slidably disposed to be guided by engagement with the adjacent faces of the casing structure 14 and is integral with jaw 12. It is formed with a threaded bore 16 into which the correspondingly threaded shank 16 of an eye-bolt 17 extends. That bolt mounts a collar 18 fixed with respect to its shank and rotatably bearing against the lower face of casing 14.

Downwardly extending portions 19 are conveniently included as part of the casing structure 14 and lie one to each side of the bolt shank. The opening in the lower portion of casing 14 and through which the bolt shank extends is unthreaded. Pins 20 may be mounted on each side of the extended portions 19 to underlie the collar 18. It is, of course, apparent that in lieu of an eye-type bolt alternative units may be substituted. However, it is in many respects preferred to utilize a bolt of this type in that it lends itself to the techniques commonly employed by linesmen in connection with the mounting of assemblies by the use of a hot-line stick. It is also preferred as part of the assembly to employ a spacer bar 21 intervening the

jaws

12 and 13. These bars being preferably made of pure aluminum, they provide a short, high conductive path between the transmission line and conductor 11 or its equivalent. This bar has rearwardly extending hook-shaped parts 22 on to which may be hooked an elastic band 23 to hold the spacer in position and to allow easy removal. These hook-shaped parts 22 overlap the side edges of flange portions 24 to conveniently hold the bar against unnecessary shifting. Also it is preferred that the upper jaw 12 be defined by a downwardly and forwardly extending lip 25. The rectangular channel of the casing portion 14 is provided with a slot 14a in which rides a screw member 15a screwed into the block 15. This further serves to align the block with the channel and prevent their separation if the eye-bolt 17 is removed from the block.

Now with a view to securing conductor 1 1 against detachment from the assembly, it will be observed that in the the present exemplification lower jaw 13 is provided with extensions 26 projecting laterally beyond the plane into which upper jaw 12 extends. This extension, as in FIGS. 1 and 2, provides a lower jaw in the form of a grooved and narrowed portion 27 coextensive with jaw 13 which receives the conductor engaged by that lower jaw. Portions 27 are provided with cross members 28 at the ends of the conductor receiving channel. The narrowed portions 27 of the extensions 26 are sized and adapted to receive tap clamps 29 each of which has a generally key-hole shaped channel 30 running through it. The lower portion of the channel fits the portion 27 of the extension 26 while the upper portion of the channel is shaped to receive conductors of different diameters. The base of the channel 30 has a threaded bore 31 to receive the correspondingly threaded bolt 32 having a head 33. The bolt 32 can be screwed against the bottom of the grooved portion 27 of the extension 26 to clamp the conductor firmly against the top of the channel 30. With the clamps 29 on each side tightened the conductor will be held securely against displacement from the lower jaw 13. The assembly may thereupon be associated with a transmission line 10.

With the conductor 11 thus secrued to the lower jaw 13 by the clamps 29, the connector is now ready for application to the transmission line 10. Ordinarily a linesman will employ a hot stick which he will couple with the end 17 of bolt 16 to elevate the assembly. As a consequence of preferably employing an extended lip portion 25, no difficulty will be experienced by the operator in hooking the assembly into position. Thereafter, by rotating bolt 16,

jaws

12 and 13 will be drawn towards each other so that these jaws will intimately engage cable and conductor 11, with the intervening spacer bar pressed into firm contact with the faces of these lines. With this disposition of the parts established, then the hot stick may be uncoupled from the assembly and a proper tap-off will have been provided.

To insure full contact between the insulated line 10 and the conductor 11 a series of insulation piercing teeth 34 are embedded in the upper groove of the spacer bar 21. These teeth pierce the insulation sheath when the connector tightening torque is applied. These teeth are mounted in the spacer bar and are preferably made from a softer material than the pad itself. This softer material allows the teeth to pierce the insulation, contact the metal conductor and then flow along it rather than to penetrate it. This results in a flattened, full contact, adequate electrical connection. In turn the flattened teeth, mushroomed as they are, within the insulation prevent backout of the teeth if the connector is to be removed. Consequently, the pressure spacer pad, because of its removable, flexible rubber band attachment, separates from the connector and stays in location on the run conductor- 10. With the pad so locked, easy re-connection can be made by the connector to the pressure pad without further puncturing of the insulation.

The piercing teeth 34 have a geometry to pierce insulation and hardness less than that of the conductor strands causing teeth to fold over strands increasing contact area and locking under uncut insulation. This allows the possibility of transferring relatively high cur rents as teeth can be added for more contact area without damaging run conductor. The connector in such case will in effect be a one-shot device, because with the mushrooming attachment the connector is locked to the conductor and can only be removed by tearing the piercing holes.

It will be understood that additional teeth may be provided to increase the contact between the connector and the line 10 and the connector and the conductor 11. FIGS. 6 and 7 illustrate another series of teeth 35 in the groove of the upper jaw 12. If necessary or desirable similar teeth could also be added to the lower groove of the spacer 21 or the groove of the lower jaw 13.

Thus, among others, the several objects of the invention as specifically aforenoted are achieved. Obviously, numerous changes in construction and rearrangement of the parts may be resorted to without departing from the spirit of the invention as defined by the claims.

' What is claimed is:

1. In a connector assembly for attaching a tap-off conductor to an insulation sheathed high voltage line of the type including upper and lower clamping jaws and first attachment means connecting said upper and lower jaws with said upper jaw shiftable toward and away from said lower jaw and first shifting means forming a part of said first attachment means for shifting said upper jaw toward and away from said lower jaw that improvement comprising:

alignment means for initially aligning said tap-off conductor with respect to said clamping jaws;

a conductor spacer bar supported between said jaws and shiftable therebetween which conductor bar is detachably affixed to the assembly and is provided with insulation piercing teeth positioned to pierce the insulation of the high voltage line;

said alignment means including a lateral extension on each side of said lower jaw, which lower jaw and said lateral extensions provide an elongated seat for the tap-off conductor extending beneath the conductor bar;

tap conductor clamps shaped to receive the said lateral extensions and the tap-off conductor .and having means for fastening said tap-off conductor to said assembly with said tap-off conductor held on each side of said lower jaw and beneath said conductor bar;

whereby said assembly can be attached to said high voltage line with said high voltage line between said upper jaw and said conductor bar and said upper and lower jaws can be brought toward each other by said first shifting means with said high voltage line and said tap-off conductor engaging said conductor bar in clamped relation with the teeth of the conductor bar piercing the insulation of the high voltage line and the tap-off conductor engaging said conductor bar in clamped relation to form a full contact electrical connection between the high voltage line and tap-off conductor; and said insulation piercing teeth made of a hardness less than that of the strands of the high voltage line to allow the teeth to pierce the insulation sheath of the high voltage line and mushroom under pressure against the said strands to make a flattened, full contact, adequate electrical connection between the conductor bar and the high voltage line.

Claims

1. In a connector assembly for attaching a tap-off conductor to an insulation sheathed high voltage line of the type including upper and lower clamping jaws and first attachment means connecting said upper and lower jaws with said upper jaw shiftable toward and away from said lower jaw and first shifting means forming a part of said first attachment means for shifting said upper jaw toward and away from said lower jaw that improvement comprising: alignment means for initially aligning said tap-off conductor with respect to said clamping jaws; a conductor spacer bar supported between said jaws and shiftable therebetween which conductor bar is detachably affixed to the assembly and is provided with insulation piercing teeth positioned to pierce the insulation of the high voltage line; said alignment means including a lateral extension on each side of said lower jaw, which lower jaw and said lateral extensions provide an elongated seat for the tap-off conductor extending beneath the conductor bar; tap conductor clamps shaped to receive the said lateral extensions and the tap-off conductor and having means for fastening said tap-off conductor to said assembly with said tap-off conductor held on each side of said lower jaw and beneath said conductor bar; whereby said assembly can be attacHed to said high voltage line with said high voltage line between said upper jaw and said conductor bar and said upper and lower jaws can be brought toward each other by said first shifting means with said high voltage line and said tap-off conductor engaging said conductor bar in clamped relation with the teeth of the conductor bar piercing the insulation of the high voltage line and the tapoff conductor engaging said conductor bar in clamped relation to form a full contact electrical connection between the high voltage line and tap-off conductor; and said insulation piercing teeth made of a hardness less than that of the strands of the high voltage line to allow the teeth to pierce the insulation sheath of the high voltage line and mushroom under pressure against the said strands to make a flattened, full contact, adequate electrical connection between the conductor bar and the high voltage line.