GB2496253A - A system for anchoring fence posts - Google Patents

Abstract

The system comprises a base plate including an area 17 to support a ballasting weight and a means for locking a fence post 20, 21 to the base plate. In use the locking means and area are located so they are both on the same side of the fence. The posts are hollow and are supported on the base plate by members which extend upwardly from the base plate and are inserted into the posts. In use the posts are able to rotate relative to each other so that the shape and orientation of the fence can be varied. Engaging members extending radially from a lower portion of the posts are engaged with fixed members on the base plate. The fence posts may be locked to the base by having plates 24, 25 welded to the posts and having a portion of the plates 26, 27 being located underneath flange 16 to prevent the posts being lifted up. Also claimed is at least one barrier on the base plate to secure any mass placed on the plate.

Description

BASE AND LOCKING SYSTEM FOR SECURITY FENCE

This invention relates to security fences, and in particular a base for anchoring sections of a fence to the ground in such a way as to prevent the fence being lifted.

In permanent security fencing systems, fence panels, which may include electrified wires on one side, extend between posts that are set in the ground, usually in concrete. Security fences may however also be required in circumstances where it may not be feasible to set posts into the ground, for example if a fence is intended only to be temporary. Free standing fences can however sometimes be lifted up, for example by inserting a lever such as a crowbar underneath.

The present invention provides a system for anchoring fence posts comprising a base plate having an area to support a weight and, spaced from said area, means for locking a fence post onto the plate such that, when the fence post is supporting a fence the weight supporting area and the locking means lie on the same side of the fence. The system of the invention can be used to support a fence on a substantially flat surface without the need to bury one end of the fence post. The system can thus be used on solid flat surfaces such as asphalt or concrete. Additional means may nonetheless be provided for anchoring the plate to the ground when it is positioned on softer ground into which securing pins or the like can be driven.

The fence post locking mechanism preferably comprises an upright support slidably engagable with a fence post, the fence post also being rotatable about the axis of the upright support and having an engaging member extending radially from its lower end to engage a fixed member on the base plate.

The base member of the invention will usually have two said upright supports side by side so as to engage two adjacent fence posts, each rotatable about its respective support so that two adjacent fence panels can be supported at any desired angle relative to one another and to the base plate, while their respective engaging members can engage the fixed member on the base over a wide angular range.

The upright support is preferably cylindrical, with a diameter such that a fence post of box section, preferably square section, can slide over it with just sufficient play to allow both sliding and rotational movement. The locking mechanism preferably comprises as an engaging member a plate secured to the bottom of the fence post so as to rotate with it in a plane perpendicular to the axis of rotation of the post, so that when the fence post is in position the locking plate can be rotated into and out of the fixed engagement on the base plate. The fixed engagement may be a simple flange rigidly mounted on the base place, suitably of adjustable height. The engaging member preferably extends on one side only of the fence posts, so as to be entirely behind the fence in its locked position, offering no opportunity for interference from outside.

The support system of the invention should be of rigid material and preferably of a metal, more preferably steel. To hold the system down, a suitably heavy weight can be used, preferably of at least 100 kilograms. While a metal weight or concrete block could be used for this purpose, these are difficult to manoeuvre and an alternative would be to place a large container on the support plate and fill it with a heavy material such as wet sand or such other material as may be to hand. The base plate may have a barrier or barriers around its periphery to prevent the weight being pushed off the plate.

The base plate preferably extends a distance of at least 40 cm from the fence post, typically 50 to 70 cm. On the other hand the base preferably does not extend more than 20 cm from the post on the side opposite the post, to minimize the possibility of its being levered upwards.

A preferred embodiment of the invention will now be described with reference to the accompanying drawings wherein: Figure 1 shows a support base for a system in accordance with the invention; Figure 2 shows how two fence posts can be mounted on the vertical supports of the base of Figure 1; Figure 3 shows the system of Figure 2 in a different position; Figure 4 is a top plan view showing how two fencing panels can be supported by the base of the invention at different angles; Figure 5 is an elevational view showing two fence panels supported by the system of the invention and held down by a weight; Figure 6 is a perspective view of a system in accordance with another embodiment of the invention, with the weight removed for clarity, and Figure 7 is a front elevation of the system of Figure 6, with different fence panels in position.

Referring first to Figure 1, a support base 10 in accordance with the invention comprises a flat steel plate 12 having at one end a broad area 17, on which a weight can be positioned to hold the plate down, and at its other end a pair of cylindrical upright fence post supports 13, 14 which are welded to the base.

Also secured to the base, at a position towards but spaced from the uprights, 13, 14, is a vertical plate 15 to which is secured a steel angle section 16 by nuts and bolts 18. These are mounted in vertical slots 11 to allow adjustment of the height at which the angle piece is secured. The plate 15, like the vertical supports 13, 14 can be welded to the base. The angle section has a horizontal elongate flange 30 extending towards the upright supports 13, 14.

Referring now to Figure 2, a pair of fence posts 20, 21 of box section steel have been slid over the upright supports 13, 14. These fence posts can for example support rigid mesh panels and electric wires, but for clarity these are not shown in Figures 2 or 3. The posts 20, 21 are each rotatable about a vertical axis, around the fixed upright supports 13, 14 on which they are mounted.

To the bottoms of posts 20, 21, are welded respective support plates 22, 23, extending outwardly from the posts on which they are mounted. The mesh or other type of fencing panel supported by each of the posts 20, 21 will extend away from the posts on which they are mounted, at right angles to respective support plate 22, 23 in each case, i.e. in the directions of arrows a, b.

On to the bottoms of posts 20, 21 are welded respective flat locking plates 24, 25, again of steel, each being essentially quadrant-shaped, with a respective extension 26, 27 to engage below the fixed engagement flange 30. It can be seen that either of posts 20, 21 could be rotated about a vertical axis so that its respective locking plate disengages from the fixed flange 16, to enable the post to be removed from its upright support.

In the configuration shown in Figure 2, with the fences supported by posts 20, 21 extending in the directions of the arrows, it can be seen that the fences will be at an angle of about 90° relative to one another, the right angle being on the outside of an enclosure to be surrounded by the fence, since the plate 17 and the locking mechanism are designed all to be within the enclosure and out of reach of potential intruders. Even in this position, the extensions 26, 27 of the locking plates are engaged under the fixed flange 16.

In the configuration shown in Figure 3, the fence posts 20, 21 have been rotated so that fence panels supported by them would be again at 90° relative to one another, but in this case with the right angle encompassing the weight support 17 and the locking mechanism inside the fenced enclosure. In this configuration, the locking plates 24, 25 overlie one another but both extend under the horizontal locking flange 30. The locking mechanism of the invention can thus secure fence panels over a wide range of angles relative to one another, from 90° to 270° relative to the inside of the enclosure.

Figure 4 shows a top plan view of a pair of fence panels 40, 42 supported by posts 20, 21 mounted on the fixed upright supports 13, 14. Each fence panel comprises a rigid mesh 44, 46 on the outside of the enclosure and electric wires 43, 48 on the inside, supported by insulators 45, 47 attached to the respective fence posts. The configuration of the fence panels in Figure 4 is intermediate between those of Figures 2 and 3.

The fence panels 40, 42 are shown in more detail in Figure 5. These can be of a conventional type, with mesh panels 44, 46 welded to the outer surfaces offence posts 20, 21 and electric wires such as 48 forming a parallel internal barrier supported by insulators 45, 47 mounted one above the other on each post, and anchored to the respective post.

Figure 5 also shows how blocking plates 24, 25 overlie one another and extend below blocking flange 30, thus preventing either post from being lifted vertically off its internal upright support.

Also shown in Figure 5 is a heavy weight 50 placed on the plate 12, to prevent lifting of the device. The weight is preferably of 100kg or more.

It can be seen that when a fenced enclosure is erected using the support and retaining devices of the invention, the base plate 12 can simply lie flat on the ground without itself necessarily being secured to the ground. The weight 50 is shown as being located inside the enclosure formed by the fence panels 40, 42 as is most of the base plate 12. Only a small part of this projects outside the fenced enclosure, making it difficult to lever it up by placing a crowbar or the like underneath. The weight 50, which can conveniently put in place by positioning an empty container such as a plastic barrel on the plate 17 and then filling it with heavy material such as wet sand, makes it difficult to lift the plate and it cannot itself easily be pushed off the plate from outside the fence. Locking of the fence posts 20, 21 onto their supporting plate 12 by engagement of the locking plates 24, 25 under fixed flange 30 means that the fence posts cannot be lifted from the base.

While the system of the invention can support a security fencing system on a hard surface such as asphalt or concrete, lifting of the base 12 can be made even more difficult if the system is on slightly softer ground, by driving stakes 52 through the holes 19 in the base plate into the ground, again on the inside of the enclosure so that they cannot be got at from the outside.

When the fence is erected, the tops of the two adjacent posts on each base can be locked together by any suitable means, to make them still more difficult to move. The whole enclosure thus becomes a large, rigid, integral structure, the integrity of the whole making it difficult to move any individual part.

Referring now to the embodiment of Figure 6, this embodiment comprises a base plate 60 similar to that of the embodiments of Figures 1 to 5, but of simpler shape, elongate with parallel straight longitudinal sides and arcuate or semi-circular ends. In this embodiment, barriers 62 are positioned on each side of the base plate and a further barrier 64 is positioned at the end of the plate opposite the fence posts, these barriers being rigidly secured to the base plate, for example by welding, to prevent the weight from being pushed off the plate.

A fixed member 66 is provided in the form of a bar, again rigidly secured to the base plate, with an elongate gap 69 underneath it for the engaging member (not shown) of the fence panel to engage. In this embodiment, the fence post 60 forms part of a rigid outer frame for the fence panel, this fence panel also including a bottom strip 65. The engaging member, which may have a quadrant shape to engage in a similar way to the corresponding part in the embodiment of Figures 1 to 5, may be formed integrally with the bottom strip 65.

The fence panel supported within the outer frame comprises a rigid box-section steel frame 67 supporting a wire mesh screen 72. The corner of the fence panel shown in Figure 6 is fitted with a triangular plate 68, which may be welded to the inside or outside of the box frame, and which serves the dual function of strengthening the frame and screening the weight and locking mechanism from the outside. It is thus made still more difficult for a pole or the like to be poked through the mesh to try and move the weight.

The embodiment of Figure 7 is similar to that of Figure 6 except that the fence panels 70 are not formed with an outer frame, the fence posts 74 each being an integrally formed part of a fence panel. As in the case of the embodiment of Figure 6, corner plates 68 are provided to strengthen the frame and to help screen the weight 76.

An arcuate locking plate 75 is integrally formed at the bottom or each of the fence posts 74, to engage under the rigid bar 66 to lock each of the fence panels in place.

There is thus provided a fence post support and retaining system which can support a fence on hard ground without the need for burying the fence posts or setting them in concrete. Lifting one fence post or pair of fence posts is made more difficult by the fact that applying any kind of upward leverage pushes the rigid fencing panel against the fence post supporting it at its opposite end, which will also be held down by the system of the invention.

Claims (1)

1. <claim-text>CLAIMS1. A system for anchoring fence posts comprising a base plate having an area to support a weight and, spaced from said area, means for locking a fence post onto the plate such that when the fence post is supporting a fence the weight-supporting area and the locking means lie on the same side of the fence, wherein the fence post locking mechanism comprises an upright support fixed to or integral with the base plate and slidably engagable with a fence post, the fence post also being rotatable about the axis of the upright support and having an engaging member extending radially from its lower end to engage a fixed member on the base plate.</claim-text> <claim-text>2. A system according to claim 1 wherein the engaging member extends on one side only of the fence post so that in its engaged position it does not extend in front of the fence.</claim-text> <claim-text>3. A system according to claim I or claim 2 comprising two said upright supports positioned side by side on the base plate so as to engage to adjacent fence posts, each rotatable about its respective support so that two adjacent fence panels can be supported at any desired angle relative to one another and to the base plate.</claim-text> <claim-text>4. A system according to any preceding claim wherein the or each upright support is cylindrical, with a diameter such that a fence post of box section can slide over it with just sufficient play to allow both sliding and rotational movement.</claim-text> <claim-text>5. A system according to any preceding claim wherein the locking mechanism comprises a plate secured to the bottom of the fence post and extending radially outwardly from it, rotatable with said post in a plane perpendicular to the axis of rotation of the post, into and out of engagement with a fixed engagement member on the base plate.</claim-text> <claim-text>6. A system according to claim 5 wherein the fixed engagement member is a flange extending above the base plate and parallel thereto, under which the radial engagement plate can engage to prevent lifting of its associated post.</claim-text> <claim-text>7. A system according to any preceding claim further comprising means for securing the base plate to the ground.</claim-text> <claim-text>8. A system according to claim 7 wherein the means for securing the base plate comprises apertures therein through which pins or pegs can be driven into the ground.</claim-text> <claim-text>9. A system according to any preceding claim further comprising a barrier or barriers positioned around the periphery of the base plate to retain a weight in position on the base plate.</claim-text> <claim-text>10. A security fence comprising a plurality of systems according to any preceding claim spaced from one another with fencing panels extending between them, each said fencing panel being secured to a fence post locked onto its respective base plate, a weight being positioned on each said base plate.</claim-text> <claim-text>11. A base and locking system for a security fence, substantially as herein described with reference to and as illustrated in the accompanying drawings.</claim-text>