GB2067629A - Fence structures - Google Patents

Abstract

A fence post comprises a lower portion (8) adapted to be secured in the ground with a short terminal part protruding above the ground, and an upper portion secured to the lower portion by resiliently deformable connector means. The connector means may be in the form of a coiled spring 12 or a plastics or rubber block and abutment stops may be employed to restrict relative displacement of the post portions. <IMAGE>

Description

SPECIFICATION Improvements relating to fence structures By the term "fence structure" as used herein, we mean a semi-permanent structure which is or may be erected to extend along one or more sides of an area to or from which it is desired to restrict access, whether by animals or persons.

A conventional fence structure comprises a plurality of posts erected vertically at spaced intervals with cladding (which may be of wire mesh) secured to and extending between adjacent posts. Lower end portions of the posts are secured in the ground, typically by being set into concrete, to afford the fence structure with a required degree of stability. The fence posts are typically of reinforced concrete, or of tubular steel.

A problem is encountered where a fence structure is erected alongside an area which is used by motor vehicles. When a motor vehicle collides with a fence post, damage may be caused to the fence post which necessitates its replacement. This involves disconnection of the damaged post from adjacent cladding, removal of the post from the ground, and its total replacement by a new post, or by a repaired post, to which the cladding is re-secured.

Additionally since fence posts are rigid, damage may be caused to the vehicle.

According to this invention there is provided a fence structure comprising a plurality of posts, each comprising a lower portion adapted to be fixedly secured in the ground, and an upper portion secured to the lower portion by resiliently deformable connector means.

The fence structure preferably comprises stretcher means (e.g. wires) secured to and extending between the posts under some tension, and cladding, such as wire mesh.

By the use of this invention, if a vehicle collides gently with an upper portion of a fence post, said upper portion will be deflected relative to the lower portion to which it is secured, without necessarily causing permanent damage to the post, and tending to reduce the occasion of damage to the vehicle itself. When the vehicle then moves away from the post, the post, by virtue of the resilience of the connector means, will return to its original position.

Should the vehicle collide with the fence post with a degree of force such as to cause damage to the upper portion of the post, a high probability will exist of the lower portion of the post remaining in place, and intact: thus, the invention allows removal of the damaged portion of the post, leaving the lower portion in position, and a new or repaired upper portion may be secured to the lower portion, without the requirement of digging up, and resetting a new lower portion.

Preferably the lower portions are adapted to be secured in the ground with part, preferably not exceeding 1 2 inches, and more preferably not exceeding 9 inches, projecting above the ground: thus the lower portions afford fixed elements of the fence structure to which a lower stretcher wire may be secured, whilst not projecting vertically upwardly a distance which will render them susceptible to damage, by the outermost parts of a vehicle, for example the vehicle bumper.

Preferably the upper portion is releasably secured to the resiliently deformable connector means, and the resiliently deformable connector means is releasably secured to the lower portion.

Such a construction allows ready removal of the upper portion, and/or the connector means, should this be required for the purposes of replacement.

Most conveniently the connector means is afforded by a heavy duty, close-coiled tension spring. Where the fence posts are hollow and tubular, most conveniently the tension spring extends into the interior of both the lower portion and the upper portion. Thus advantageously the outside diameter of the spring at rest is slightly greater than the internal diameter of the hollow post portions: this allows the spring to be "screwed" into the fixed, lower portion, and the upper portion to be screwed onto and over the free, protruding portion of the spring.In this manner the degree of resilience of the upper potion relative to the lower portion may readily be adjusted, by varying the length of spring exposed between the facing ends of the upper and lower portions: in practice it has been found that an exposed length of about 2 inches gives an acceptable degree of resilience: it will however be appreciated that resilience of the upper portion relative to the lower portion will be present, even when the ends of the upper and lower portions are in close proximity.

Alternatively when a tension spring is being used as connector means, the spring may be mounted on the lower portion of the fence post so as to extend around the exterior thereof, similarly extending around the exterior of the upper portion when the upper portion is "screwed" into the spring. Alternatively, if desired, the spring may extend around the outside of one of its portions, and extend into the interior of the other portion.

As an alternative to the use of a tension spring, a resiliently deformable element such as of plastics or rubber may be used, particularly in circumstances where the posts are of non-circular cross-section. Thus, an element of neoprene rubber may be inserted into the hollow interior of the lower portion, with an upper part of the element projecting above the lower portion, the upper portion of the fence post being mounted on said projecting part of the neoprene element.

If desired the fence structure may comprise means, cooperable between the upper portion of each fence post and the lower portion, or with the ground, to limit resilient deformation of the upper portion of the post, relative to the lower portion.

This invention also provides a fence post suitable for use in the erection of a fence structure according to the invention.

There will now be given a detailed description, to be read with reference to the accompanying drawings, of three fence structures, which are preferred embodiments of this invention and which have been selected to illustrate the invention by way of example, said fence structures each comprising fence posts which are themselves illustrative of the invention.

In the accompanying drawings: FIGURE 1 is a schematic side elevation of part of a fence structure which is a first embodiment of this invention, illustrating the fence post thereof; FIGURE 2 is a side view of the post illustrated in Figure 1, showing restrictor means thereof: FIGURE 3 is a view of a fence post of different construction, this Figure also illustrating the position adopted by an upper portion of the fence post relative to a lower portion thereof, under load; and FIGURE 4 is a view of a third construction of fence post.

The fence structure which is the first embodiment of this invention comprises a plurality of fence posts 6, each comprising a lower portion 8 and an upper portion 10, both the upper and lower portions being of hollow sleeve tube. Each post is erected with the lower portion 8 set into a mass 10 of concrete below ground level, with part of the portion 8 (preferably about 6 inches) extending above ground level. Secured to the end portion 8 within the mass of concrete is a rectangular plate 9 to improve the stability of the post portion.

Each fence post comprises resiliently deformable connector means, provided by a heavy duty, closely coiled tension spring 12, whose outside diameter is slightly greater than the internal diameters of the portions 8 and 10. A lower part of the spring 12 is inserted into the projecting part of the portion 8, being held in position by frictional forces produced by the radial compression of the spring 12. The above portion 10 of the fence post is mounted on the upper part of the spring 12 in a similar manner, with a gap, typically of about 2 inches, between the lower end of the portion 10 and the upper end of the portion 8.

The lower portion 8 and upper portion 10 are provided with lugs 14, 16 respectively.

The fence structure comprises a number of such posts 6 erected at spaced intervals, with horizontal stretcher wires 1 8 connected to and extending between the lugs 14 and 1 6 of adjacent fence posts. The fence structure also comprises cladding, which in the preferred embodiment is in the form of chain link 22, secured in position by said horizontal stretcher wires 18, and by vertical stretcher wires 20 extending between the lugs 14 and 16 of each post.

Aiternative to the use of lugs, the horizontal stretcher wires 1 8 may pass through holes in the post portions with the vehicle wires 20 being secured to the wires 1 8.

If a vehicle collides with a fence post, the probability will be that it will collide with an upper portion 10, and said upper portion 10 will be deflected relative to the lower portion, as is shown in Figure 3. When the vehicle moves away from the post, the upper portion 10, by virtue of the resilience of the spring 12, will readopt its vertical position.

It will be appreciated that the resistance of the upper portion 10 to deflection is provided not only by the spring 12 of that post, but also by means of the stretcher wires 1 8 connecting said post to adjacent posts.

Should the upper portion 10 of any fence post be damaged, the stretcher wires may be disconnected from the lugs 1 6 thereof, said upper portion 10 may be removed from the spring 12, and a new or repaired portion 10 may be placed in position, and the stretcher wires secured to the lugs 1 6 thereof. This may be accomplished easily, and without the previously encountered difficulties of digging the post from the ground, and resetting a new or repaired post in concrete.

The advantage of mounting the lower portion 8 so as to project a short distance above ground level, is that it provides the fence structure with a part which is fixed in relation to the ground.

However, if the circumstances of the fence structure are such that damage may be occasioned at a point adjacent to ground level, the lower portion 8 may be set into concrete so as not to project above ground level. In such construction the lugs 14 may either be disposed at the upper extremity of the portion 8, or may be disposed at the lower extremity of the portion 10.

As is shown in Figure 2, preferably the post illustrated in Figure 1 comprises means to restrict displacement of the upper portion 10 relative to the lower portion 8. Conveniently said means is afforded by a stop 24 secured to and extending downwardly from the portion 10, and a stop 26 secured to and extending upwardly from the portion 8, with a small gap between the stops 24 and 26. Thus, from the position shown in Figure 2, the upper portion 10 may be deflected to an extent at which the stops 24 and 26 are brought into engagement, whereupon further deflection of the upper portion 10 will be resisted.

Conveniently one of the stops (such as the stop 24) comprises screw-threaded means, whereby the gap may be adjusted, as is desired.

The fence structure which is the second embodiment of this invention comprises a plurality of fence posts 36, each comprising a lower portion 38 and an upper portion 40. As is illustrated in Figure 3, the lower portion 38 is in the form of a solid spigot, with the resiliently deformable connector means, afforded by a spring 42, extending around the exterior of the portion 38.

However, the upper portion 40 is, as in the first embodiment, of hollow tubular shape, with the spring 42 extending into the interior thereof.

It will be appreciated that the invention may be utilised with the spring extending around the outside of both the upper and lower portions, or around the outside of the upper portion and into the hollow interior of the lower portion.

Further, whereas the use of heavy duty closely coiled tension springs is particularly suited to the use of hollow fence posts of circular cross-section, adequate contact between the spring and the post portions may be obtained even where the post sections are of non-circular cross-section.

The fence structure which is the third embodiment of this invention is similar to that illustrated in Figure 1, save for the fact that a solid element 72 of resilient elastomeric material (such as neoprene rubber) is utilised in place of the spring 12, said element 72 being fitted under compression into the lower portion of said post, and the upper portion of said post being pressfitted down onto the projecting portion of the element 72.

Claims (14)

1. A post for a fence structure, comprising a lower portion which in use is fixedly secured in position and an upper portion secured to the lower portion by resiliently deformable connector means.

2. A post according to Claim 1 wherein the upper portion is releasably secured to the connector means.

3. A post according to one of Claims 1 and 2 wherein the connector means is releasably secured to the lower portion.

4. A post according to any one of the preceding claims wherein the connector means comprises a heavy duty, close-coiled tension spring.

5. A post according to any one of Claims 1 to 3 wherein the connector means comprises a resiliently deformable element of plastics or rubber.

6. A post according to any one of the preceding claims wherein the upper and lower portions are hollow and tubular, with the connector means extending into the interior of both the lower portion and the upper portion.

7. A post according to any one of the preceding claims comprising means, co-operable between the upper portion and the lower portion, or with the ground, to limit resilient deformation of the upper portion of the post relative to the lower portion.

8. A post for a fence structure constructed and arranged substantially as hereinbefore described with reference to any of the accompanying drawings.

9. A fence structure comprising a post according to any one of the preceding claims.

10. A fence structure according to Claim 9 comprising stretcher means secured to and extending between the posts under tension.

11. A fence structure according to one of Claims 9 and 10 wherein the lower portions are of the posts are adapted to be secured in the ground with part projecteding above the ground.

12. A fence structure according to Claim 11 wherein said part does not exceed 9 inches in height.

13. A fence structure according to any one of Claims 9 to 12 wherein the lower portions afford fixed elements of the fence structure to which a lower stretcher wire may be secured.

14. Any novel feature or novel combination of features hereinbefore described and/or shown in the accompanying drawings.