US2821365A - Electrical wire fence with plastic posts - Google Patents

Description

Jan. 28, 1958 J. LACH V ELECTRICAL wm: FENCE wrm PLASTIC POSTS Filed .mn 25.11955 FIG. 4

INVENTOR JOHN LACH I ATTORNEY Un ed ees P ELECTRICAL WIRE FENCE WITH PLASTIC POSTS John Lach, Oak Harbor, Ohio Application June 23, 1955, Serial No. 517,468

' 1 Claim. Cl. 256-19) 7 This invention relates to a novel post construction, and more particularly relates to a new and improved, electrically non-conductive, plastic fence post.

Up to the present time, posts adapted to be driven or otherwise placed in the ground have been formed from a variety of materials. In most instances, however, either wooden or steel posts have been employed in conventional fence construction.

Despite the higher cost and the difliculties encountered by the relatively rapid corrosion rate of steel, even when coated with corrosion resistant paint or other coating, steel posts are widely used. Posts formed of more corrosion resistant metals or alloys, while generally minimizing the problem of corrosion, usually are too costly, or not readily available, thus precluding their use on a large scale.

Wooden posts, while generally available at a cost less than, or competitive with, steel posts, are susceptible to decay, rot, and insect attack. Although chemical treatment can be employed to minimize much of the insect attack, or decay, the cost of such treatment and/or the practical difficulties involved in chemically treating such posts seriously limits such protection.

Thus far it will be appreciated that neither wood nor metal, though commonly used, are completely satisfactory as materials of construction for fence posts or other posts to be driven into the ground or placed in the ground by other means.

The difliculties heretofore encountered are magnified in the construction of the so-called electrically charged fences which provide an electrical shock on contact therewith.

Such fences are finding increasing application because of their effectiveness in retaining animals with a minimum of wire in comparison with conventional fence construction.

While the wooden or steel posts heretofore employed in electrically charged fences are, of course, susceptible to the aforementioned diflicnlties, additional problems are encountered in maintaining a proper electrical circuit through the fence. In the past, a multiplicity of insulators secured to the posts have been employed to prevent short circuiting or grounding of the electrically charged wire. Such insulators, typically formed of ceramic ware, have been secured to the posts, and one or more wires supported thereby. It will be appreciated that in addition to the expense of installing such insulators, further cost frequently is involved in their maintenance and periodic replacement.

Hence, the principal object of this invention is to avoid the problems heretofore encountered in post construction and to provide a new and improved fence post.

A further object of the invention is to provide a novel electrically insulating post construction.

These and other objects and advantages of the invention will become more apparent from the following description thereof.

The present invention comprises a solid, electrically Patented Jan. 2a, 1958 non-conductive, plastic post adapted to be driven into the ground or otherwise placed therein, said post compris ing in cross-section a curved element having a reinforcing rib integrally joined to its convex surface. More particularly, this invention comprises a solid, electrically non-conductive organic plastic fence post comprising in cross-section a semi-circular element having a reinforcing rib integrally joined to its convex surface.

In the drawing:

Fig. 1 is a perspective view, with parts broken away, of a plastic post embodying the invention;

Fig. 2 is a sectional view taken along the line 22 of Fig. 1;

Fig. 3 is a fragmentary elevational view of the post shown in Fig. 1; and

Fig. 4 is a fragmentary perspective view of a portion of fencing embodying this invention.

Referring more particularly to the drawing, Fig. 1 illustrates a post, indicated generally at 10, embodying the preferred post construction of this invention. As shown in Fig. 1, post 10 has a cross-section comprising a semi-circular element 12 having a reinforcing rib 14 integrally secured thereto substantially at the circumferential midpoint of its convex surface 16. At the lower portion of the post 10 is aflixed a brace or steady plate 18. This plate 18 is secured to the curved edges 20 and 22 of post 10 by gripping flanges 24 and 26, which flanges are either pressed out of the plate 18 or secured thereto by other means (not shown). Post 10 is provided with at least one slot 28 adapted to receive and support a wire, e. g., the wire 30 shown in Fig. 4.

While a semi-circular element 12 is shown and is presently preferred, it will be understood, of course, that certain other curved elements also may be used. Similarly,

while a pentagonal steady plate 18 is shown, plates of other shapes, attached in the same manner, also may be employed. The bottom of the post 10 is cut at an angle, typically 60 with respect to the ground, to facilitate entry of the post into the ground. In certain applications, the steady plate 18 may be slidably secured to the post thereby to permit driving the post into the ground, with subsequent driving of the steady plate to a different depth than would be accomplished if there were no relative sliding motion between the post 10 and plate 18.

While the proportions of the post cross-section may be varied somewhat, it is preferred to employ a construction wherein the rib 14 extends from the convex surface 16 a distance at least equal to a radius of the concave surface 17 as shown in Fig. 2 and not substantially greater than a radius of the convex surface 16. The length of the post will, of course, be dictated by practical considerations and the application intended.

Fig. 3 illustrates the preferred method of securing a steady plate to the post, which method can either result in a rigid immovable mounting or in a slidable connection permitting relative longitudinal movement between the post and the plate.

Fig. 4 shows a portion of an electrically charged fence in accordance with this invention and comprising an insulated or more commonly, an uninsulated wire 30 which may be either plain or barbed wire, and a plurality of solid, plastic, posts 32, 34 and 36. In operation, these posts are placed in the ground and serve to support the wire 30 which is connected to an electrical energy source (not shown). As shown in Fig. 4, the wire 30 is secured to the posts by slots 38, 40 and 42. Thus, it will be appreciated that proper operation of the electrically charged fence is accomplished without the aid of any separately attached insulators since the posts themselves are electrically insulating.

In some instances, if desired, other means may be employed to secure the wire to the posts, e. g., wires disposed around the posts, or a slot, having a V-shaped cross-section, cut in the rib 14, thereby to aiford a crimping action on the wire.

The plastic material embodied in a post of this invention is an electrically-insulating organic plastic having sufficient rigidity to provide the strength and durability necessary.

While the particular plastic substance employed will, of course, be dictated by the specific application intended, in general it is preferred to employ a thermosetting resin or a thermoplastic resin which is so formulated as to insure adequate strength and rigidity Without disabling brittleness over the range of temperatures to be encountered. Illustrative of commercially available resins of the foregoing types are phenol-formaldehyde resins, urea-formaldehyde resins and melamine-formaldehyde resins.

It is contemplated that such resins may contain conventional fillers, extenders, diluents or lubricants, including such materials as fabric, e. g., chopped, fibrous or in web form. Also included may be suitable curing agents, catalysts, and the like. Posts embodying the invention may be formed by extrusion, molding or other fabrication means suitable for the plastic selected. It is to be understood that, although the invention has been described with specific reference to particular embodiments thereof,

it is not to be so limited since changes and alterations therein may be made which are within the full intended scope of the invention as defined by the following claim.

I claim:

A fence construction comprising, in combination, a plurality of solid, electrically-insulating, organic plastic fence posts having slots in their upper portions to receive and support an uninsulated electrical Wire, each of said posts comprising in cross section a semi-circular element having secured to, and extending outwardly from, the circumferential center of its convex surface a reinforcing rib integrally joined thereto and extending from the convex surface a distance at least equal to a radius of the concave surface of said post, and an uninsulated wire secured in and supported by said slots.

References Cited in the file of this patent UNITED STATES PATENTS Milliken Sept. 29, 1891 Seymour Apr. 23, 1907 Frost June 28, 1910 Frantz Mar. 31, 1914 Klumb Dec. 31, 1946 Du Batta et a1 Mar. 20, 1951

Images