US2434123A - Ground line bond - Google Patents

Description

Jan. 6, 1948. F. G. RIDGERS ET AL' 3 GROUND LINE BOND Filed Feb. 15, 1945 Patented Jan. 6, 1948 UNITED STATES PATENT OFFICE ass sz Hami ton, Ontario, Cana a, ass gn rs o Sla er C mpa Limited, H m ton, 011:

ario, Canada Application February 15, 1945, Serial No. 578,010

4 Claims.

This invention relates to improvements in the art of bonding ground lines to ground rods and consists essentially of a novel .tie arrangement between the line and the rod whereby the line is loosely connected to the rod at one part yet firmly bonded at another.

The invention is particularly adapted for use in Connection with power and telephone transmission lines, but obviously is useful in any instance where electrical current must be grounded. Such rounding devices conven iona y nsist of a unit comprising a long conductor rod which in most instances is driven deep into the ground, and a le g h of sof flexible wire whi h is bonded to he rod relatively lose o ts hoadhis en th o ire i comm nly kn wn in the line trades a the p tail, an th the rod to wh ch it is bonded is factory produced; that is, the pi tail is bonded to the rod at the factory and supplied to the trade, thence to the fieldmen or linemen as a complete unit, and as such, forms part of a linemans supply quipmen he ground lin is suitably connected or bonded to the pigtail in the field, and thus the electrical current is conducted to the ground from the ground line, throughthe pigtail and thence the rod.

Various means have been employed as a bond between the pigtail and the r-od,-but all previous methods of bonding, Whether by clamping devices or soldering and brazing, leave the wire pigtail more or less rigid but free at the point immediately adjacent the bond and therefore subject to a weakness if damaged by bending, as often happens during the driving of the rod into the ground,

and even so if the unit is mishandled. For instance, if the sledge glances from the driving head of the rod it often strikes the pigtail and bends it back on itself, sometimes to snap it en tirely and in any event to weaken it by an abrupt bending. Moreover, sometimes even the impact of the sledge succeeds in at least partially de-- stroying the bond.

The principal object of the invention, therefore, is to provide a unit consisting of a ground rod and. pigtail wherein a novel and simple arrangement or connection between the two resides apart from the actual bond, and which is reasonably flexible and to a certain degree elastic and therefore subjeet to impact, bending or other abuses without the results of such being disturbingly transmitted to the actual bonded region of the pigtail.

Another important object of the invention is to provide a device of the class specified which will be extremely simple, highly effective in its main purpose, and inexpensive to produce and to purchase.

With the above and other objects in view as will be hereinafter apparent, the invention consists in general of certain novel details of construction and combinations of parts hereinafter fully described, illustrated in the accompanying drawings and specifically claimed.

In the accompanying drawings like characters of reference indicate like parts in the several views, and:

Figure 1 is an elevation of a unit comprising a ground rod and pigtail showing a preferred form of connection and bond in accordance with the present invention.

Figure 2 is an elevation of the same structure, it having been turned on the axis of the rod n n ty e es- Figure 3 is an enlarged top cross-sectional view taken on the line 33 of Figure 1.

Figure 4 is an elevation of a portion of the rod showing a certain recess prior to the application of the pigtail.

In its present embodiment the invention consists of the ground rod l0 and its pigtail H. The rod is of common or conventional type and is here shown broken for convenience of illustration. It is, however, usually of great length and is driven deep into the ground, at least well below any possible frost penetration. Such rods are usually flexible in order to defiectingly bypass any solid obstacle below the ground line, and are sheared or otherwise pointed (l2) for easy penetration. Their great length and flexibility subjects them to vibration when they are being driven into the ground, and consequently it is easy to perceive that even an accurate sledgeman could often miss the head and instead strike the pigtail, or the sledge glance and hit the latter, with results as previously set forth.

The actual bond between the pigtail and the rod may be in any approved form, but is here shown as soldered, the solder being indicated on the drawing by heavy lines and the numeral l3. Solders are the presently preferred bonding agents, and of these, silver solder is recommended. It will be obvious, however, that any bonding means such as, for instance, brazing, or the use of any of the well known types of clamps could be successfully utilized for producing the bond as a matter of preference or under extraordinary circumstances.

The essence of the invention consists in loosely tying the wire of the pigtail to the rod directly above the actual bond, and a preferred form of tie is here typified. Starting from its bonded portion I la the wire of the pigtail curvingly bends outwardly from the rod and to one side of the axis of the bonded portion and then bends inwardly to form a substantially U-shaped bowed portion llb. Next the wire encircles the rod, at least one convolution, as a loop portion He, and finally the free end of the wire is led through the bow llb to form a half hitch and bent upwardly outside the loop but slightly outwardly free of the rod.

The loop portion No, as will be observed in Figure 3, hugs the rod closely but the internal diameter of the former and the external diameter of the latter do not quite conform, there being a slight tolerance or intervening space between the two. Thus when the soft and pliant wire of the pigtail is accidentally moved in any direction from its factory set position the loop portion He may be seen to yield or flex, and therefore it can readily be understood that any disturbance or deformation of the pigtail will be checked and not be transmitted to the portion thereof immediately adjoining the bonded portion Ila, such portion being that part which would be the most vitally affected by a blow or damage to the free or extending portion of the pigtail. In fact the free portion could be bent downwardly closely paralleling the rod and again upwardly to its normal position without disturbance to that vital or vulnerable part adjacent the bonded portion.

Obviously in production the entire pigtail is preferably shaped according to the invention prior to the bonding operation. That is, the bow lib will be formed and the loop He will be formed exactly as they have been described and are illustrated in the drawing. Then in completing the unit the loop is merely slipped over the head of the rod and slid along the same to its proper position, whereupon the bond is made.

Preferably when the bond is a soldered or brazed bond a bullet shaped recess or bed l4 may be conveniently impressed in the rod in order to partially receive the bond portion Ila of the pigtail to afford increased contact for the bond, the nose of the recess being tapered to conform to the bend in the wire at the beginning of the bow Hb.

There has thus been provided a simple and efficient device of the kind described and for the purpose specified.

It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit there- 4 of. It is not, therefore, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed.

We claim:

1. A ground rod and complemental igtail. the latter consisting of a length of wire, one end portion of said wire being bonded to the rod, the unbonded portion of said wire being loosely looped and tied about the rod to form a half-hitch immediately above the bonded portion and from the looped and tied portion extending upwardly sub stantially free of the rod.

2. A ground rod and complemental pigtail, the latter consisting of a length of wire formed with a looped portion loosely or roughly conforming in internal diameter to the external diameter of the rod and loosely fitted thereon, one end of the looped portion extending to form first a bow, and thence a bonding portion, the other end of the looped portion being passed through said bow and extending thence upwardly to form the free portion of the pigtail, said bonding portion being bonded to the rod.

3. A ground rod and complemental pigtail, the latter consisting of a length of wir formed to provide a looped portion intermediate its end p0r tions, the wire being interlocked at the termination of the looped portion and.extending thence in substantially opposite directions, one end portion forming a bonding portion and the other extending as a free portion, said bonding portion being bonded to the rod,

A ground rod and complemental pigtail con sisting of a length of wire, one end of the latter being bonded to the rod, said wire beginning from the bonded portion being bent to form a bow outstanding from the rod, thence loosely looped about the rod and passed through the bow, thence bent upwardly across the looped portion and extending to form the free portion of the pigtail,

FREDERICK GEORGE RIDGERS. CHARLES WELLMAN CASSELS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 282,250 Westinghouse July 31, 1883 1,437,613 Petersen Dec. 5, 1922 1,766,587 Banner June 24, 1930 2,346,327 Pfeiffer Apr. 11, 1944

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