US2794061A - Post with an insulator for an electric wire - Google Patents

Description

May 28, 1957 A. J. G. KEMPFF POST WITH AN INSULATOR FOR AN susc'raxc WIRE Filed May 18, 1953 INVENTOR AKDRIES JOHAN GERRIT KEMPFF AT OREY POST WITH AN INSULAI'gIlJR FOR AN ELECTRIC Andries Johan Gerrit Kemplf, The Hague, Netherlands Application May 18, 1953, Serial No. 355,640

Claims priority, application Netherlands May 17, 1952 4 Claims. (Cl. 17445) This invention relates to a pile or post provided with an insulator for fixing an electric wire thereto and more especially adapted for use in supporting the current conducting wires of an electric wire fencing.

The known posts in electric wire fencings are generally provided with insulators which may be easily damaged and wherein the fastening members securing the insulators to the posts are exposed to rusting, or said insulators present the drawback that in case of extensive installations considerable electric leakage will occur.

It is an object of the present invention to obviate these drawbacks and to provide a post construction permitting the insertion of a reliable insulator which needs no maintenance due to its safe location and the manner in which it is secured to the pile or post.

According to the invention the insulator extends in the longitudinal direction of the pile or post in a lateral recess thereof.

Another object of the invention is to provide the insulator with longitudinal inner channels through which extends at least one metal rod embodied in the pile.

A further object is to make the pile of reinforced concrete wherein said metal rod or rods form the longitudinal reinforcement of the pile.

Still further objects, features and details of the present invention will appear from the following description with reference to the accompanying drawings in which a preferred embodiment of the invention has been shown by way of example and in which:

Fig. 1 shows the upper part of a fencing pile or post according to the invention in side elevation, and

Fig. 2 is a front elevation.

The illustrated pile or post 1 is a concrete pile of substantially square cross section and provided with four longitudinal reinforcing rods, of which in Fig. 1 the rods 2 and 3 and in Fig. 2 the rods 3 and 4 are shown.

The pile 1 has a lateral recess 5 through which extend the rods 3 and 4. An insulator 6 made of porcelain, insulating glass or any other suitable material is accommodated in said recess 5. In order to increase the path for surface leakage currents, if any, the insulator may be surrounded by suitably formed thickened parts 7. The insulator 6 is further provided with two longitudinal inner channels 8 and 9 in which the rods 3 and 4 are accommodated. The space between the walls of the channels 8 and 9 and the rods 3 and 4, respectively, is taken up by fillers 10 and 11, respectively, of resilient material, such as e. g. rubber; due to this filling material no mortar can penetrate between the rods and the insulator when manufacturing the pile, and no water can gather there, either.

The extremities 12 and 14 of the insulator 6 extend somewhat beyond the upper face 13 and the lower face 15, respectively, of the recess so as to be partially embedded in the concrete mass of the pile. This arrangement causes lateral forces acting upon the insulator to be transferred directly to the concrete of the pile, so that the insulator 6 cannot move with respect to the rods 3 and 4.

trite States Patent 0 "ice This is of great importance, since otherwise moisture might easily penetrate between the insulator 6 and the faces 13 and 15 of the recess 5 and due to rusting of the rods 3 and 4 by such moisture the insulator might be cracked or damaged. Moreover, if the insulator was not rigidly secured in position, very high local compressive stresses might readily occur within the insulator near the faces 13 and 15 of the recess 5, when the pile is under such bending strain as to shorten the side of the pile containing said recess 5; and this might cause breaking of the insulator. If, however, the said insulator is effectively locked in position in accordance with this invention, the upper and lower faces 13 and 15 of the recess 5, which during moulding of the pile perfectly adjoin the upper and lower surfaces of the insulator, will transmit the compressive stresses in equally distributed manner to the insulator and the latter will thus considerably contribute to the strength and rigidity of the pile, at least when the pile is subject to a load whereby the insulator 6 lies in the compression zone. Should, however, the insulator be located in the tension zone, then the tensile stress will be taken undisturbedly by the rods 3 and 4. The strength obtained by this construction is of particular importance, when the recess is situated at a considerable distance from the pile head; this is the case, for instance, when, in addition to the recess 5 with insulator near the pile head, the pile has a second recess with an insulator for fixing a shock wire at a lower elevation.

In order to prevent rain water flowing along the pile from reaching the insulator, the upper face 13 of the recess 5 is provided with a drip rim 16.

The shock wire may be easily secured to the insulator 6 by means of a separate piece of wire passed around the central portion of the insulator. The construction is so strong that large tensile stresses occurring in the wire do not present any inconvenience, not even for corner piles.

If desired, the insulator 6 may be replaced by two insulators each enclosing one of the rods 3 and 4.

It is of great advantage that no parts extend beyond the normal cross'sectional shape of the pile, since the transport of the piles is greatly facilitated thereby.

What I claim is:

1. A post for an electric wire fencing made of concrete or other moldable material and having a laterally opening recess, at least one reinforcing rod integral with and extending through the post in the longitudinal direction thereof, said reinforcing rod having an exposed portion in said recess, and an insulator accommodated in said recess and surrounding the exposed portion of said reinforcing rod.

2. A post for an electric wire fencing according to claim 1; wherein the extremities of said insulator are embedded in the adjoining end walls defining said recess in the longitudinal direction to form an intermediate and integral block of material in said recess for taking and distributing compressive stresses occurring in the post on the side of said recess.

3. A post for an electric wire fencing made of concrete or other moldable material and having a laterally opening recess, at least one reinforcing rod integral with and extending through the post in the longitudinal direction thereof, said reinforcing rod having an exposed portion in said recess, and an insulator surrounding said exposed portion of the reinforcing rod and arranged in said lateral recess so that the outer circumference of said insulator is within the contours of said post.

4. A post for an electric wire fencing of concrete or other moldable material and having a laterally opening recess, reinforcing rods integral with and extending through the post in the longitudinal direction of the latter and spaced from the center line of said post, at least one of said reinforcing rods extending through said recess to form an exposed portion therein, and an insulator surrounding said exposed portion of said one reinforcing rod and fitted in said lateral recess "to form an intermediate member integral with the end walls defining said recess in the longitudinal direction, whereby tensile and compressive stresses occurring in the post on the side of said lateral recess are taken respectively by said reinforcing rod extending through the recess and by said in- 10 termediate members surrounding said reinforcing rod.

References Cited in the file of this patent UNITED STATES PATENTS Bissell Mar. 31, 1885 Lapp July 25, 1905 Bell Sept. 3, 1912 Gerow May 25, 1948 FOREIGN PATENTS Great Britain June 4, 1923

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