PALISADE FENCING

Abstract

A palisade fence is described comprising support posts and rails extending between the posts, and pales mounted between the rails. The rails define V-shaped apertures for receiving the pales. The pales are additionally secured to the rails by bolts

Description

PRIORITY STATEMENT

This application is a continuation-in-part of co-pending application Ser. No. 10/910,157, filed on Aug. 2, 2004, which itself claims priority from United Kingdom Application GB0321547.2 having a filing date of Sep. 15, 2003, the disclosures of which are incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to fencing, and in particular to palisade fencing.

BACKGROUND OF THE INVENTION

Palisade fencing typically comprises a number of upright support posts fixed in concrete foundations and upper and lower rails which extend between the posts and provide mounting for a plurality of upright pales secured to the rails. The pales are usually of corrugated or angled section and may have spiked or rounded upper ends, depending on the fence application. The pales are fixed by centrally located bolts to the L-section rails which are in turn secured to the H-section support posts using fish plates.

The applicant's UK Patent GB 2256447 B describes an alternative fence configuration in which the horizontal arm of each L-section rail is cut to define a number of apertures, each aperture adapted to receive the end of a pale. The pales are configured such that only a selected length of each pale end portion may pass through the respective aperture. The earlier patent describes a number of means of achieving this, and in the commercial embodiment of the invention dimples are formed on the centre line of each pale to ad as stops.

This arrangement allows a secure fence to be constructed without the requirement to bolt the pales to the cross rails and the applicant has supplied fencing of this configuration for use in a wide variety of security applications.

Of course no fence configuration can repel a sustained and determined attack and on occasion pales of fences made in accordance with GB 2256447 B have been at least partially detached from one or both cross rails by deforming or cutting portions of the apertured arm of the L-shaped cross rail, thus enlarging the aperture to allow displacement or removal of the pale.

In conventional palisade fencing, unauthorised pale removal or displacement is typically achieved by cutting one or both of the bolts which secure the pale to the vertical arms of each L-shaped cross rail. One method of cutting the bolts involves insertion of a chisel into the space between the rear of an angle section pale and the front face of the cross rail.

It is among the objectives of embodiments of the present invention to provide a palisade fence configuration which obviates or mitigates these and other difficulties.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is provided a palisade fence comprising:

support posts;

rails for extending between the posts; and

pales for mounting between the rails, the rails defining apertures for receiving the pales and the pales additionally being secured to the rails by fasteners.

Fences in accordance with the invention offer the advantage over fencing as disclosed in GB 2256447 B that cutting or deforming an apertured portion of a rail is not alone sufficient to allow displacement or removal of a pale, as the pale will remain secured to the rail by the fastener. Furthermore, where the rail has an L-section, the rear face of the vertical portion of the rail and the front face of the pale through which the fastener passes are preferably directly adjacent one another. Accordingly, there is little if any possibility of gaining access to the very short portion of fastener extending between the rail and pale, thus protecting the fastener from attack by a chisel or the like.

Reference will be made primarily herein to L-section rails having a vertical arm and a horizontal arm, the horizontal arm being apertured to receive the rail while the vertical arm receives the fastener. However, those of skill in the art will recognise that the arms of the rail could of course be at angles other than 90°, and may be inclined to the horizontal or vertical, may have a C, I or H-section, or a box section, or indeed may take a non-rectilinear form.

Preferably, the apertures are of substantially complementary shape to the pales. In a preferred arrangement, the apertures are of substantially complementary shape to end portions of the pales and the ends of the pales extend through the apertures, the end portions of each pale being provided with a projection spaced from an end of the pale such that only a selected length of each end portion may pass through the associated aperture in the rail. In a preferred embodiment, the projection on each pale end portion is provided by pressing a bead or dimple from the pale, although the projection may be formed by many different means, such as those described in GB 2256447 B, or by locating a welding bead on the pale. Where the projection is formed by a bead or dimple, the bead may be provided centrally of the pale. However, for increased security one or more beads may alternatively or in addition be provided spaced from the centre line of the pale, which beads may remain effective in restraining the pale relative to the rail even when a central part of the apertured portion of the rail is deformed in an attempt to remove a pale.

A palisade fence normally comprises an upper and a lower rail. In certain embodiments of the invention a third rail may be provided, providing additional security.

At least in the United Kingdom, palisade fencing will generally comply with British Standard BS 1722: Part 12: 1990. Specification For Steel Palisade Fences. Fencing made in accordance with this standard is typically supplied in 2.75 m long panels, each panel comprising upper and lower rails and 17 pales. In embodiments of the invention a larger number of pales may be provided, and up to 27 pales may be provided with a single panel. Increasing the number of pales in this manner has a number of benefits. One is to decrease the level of visibility through the fence, and to make it more difficult to climb the fence. Furthermore, the decreased spacing between the pales makes it more difficult to locate tools between the pales; it is known for car jacks to be located in the space between two pales, and the jack extended to create a gap through which objects or persons may pass. The decreased spacing also makes it more difficult to access the rear of the fence to attack the rail or the fastener.

The fastener may take any appropriate form, and is preferably a bolt. Preferably, the fastener passes through the front portion of the rail, typically a substantially vertical portion of the rail, and through a central portion of the pale. The bolt may be secured by a nut which engages with a rear face of the pale. The nut will preferably be of the type provided with a nut having an outer portion for engagement with a tightening tool such as a spanner or wrench, and an inner portion of a shape which is not easily gripped by a conventional tool. The two portions are frangibly connected such that when the nut is fully tightened and the operator continues to apply force to the outer portion of the nut, the outer portion will shear from the inner portion. The preferred pale has an angled or curved section and the nut is located centrally of the pale such that the inner portion of the nut is relatively inaccessible, and thus protected from attack.

Those of skill in the art will recognise that many of the features described above have utility in fencing not necessarily made in accordance with the first aspect of the invention, and may be provided in fences individually or in combination in accordance with further aspects of the invention.

In another aspect of the invention a palisade fence comprises pales, each pale having a face for location directly adjacent a face of a support rail and fasteners for securing the pales to the rail and passing through the faces.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a front view of a section of palisade fence in accordance with one embodiment of the present invention;

FIG. 2 is an end view of the fence of FIG. 1;

FIG. 3 is a sectional view on line 3-3 of FIG. 1, shown somewhat enlarged;

FIG. 4 is a sectional view on line 4-4 of FIG. 3; and

FIG. 5 is a sectional view, corresponding to FIG. 3, of a section of palisade fence in accordance with a further embodiment of the present invention.

DETAILED DESCRIPTION OF DRAWINGS

Reference is first made to FIGS. 1 and 2 of the drawings, which show part of a palisade fence 10 in accordance with one embodiment of the present invention. The fence 10 comprises a number of support posts 12 (only one shown) which provide mounting for 2.75 m fence sections or panels formed of upper and lower horizontal rails 14, 16 and spaced, upright angle section pales 18 which extend between the rails 14, 16. The posts 12 are set in concrete foundations 20 and have an H-section. The rails 14, 16 have an inverted L-section and are fixed to the posts 12 by means of fish plates 22 which pass through slots in the posts 12, in a central portion of a fence one fish plate providing mounting for two rails, one on either side of the post.

In a conventional palisade fence the pales 18 are bolted to the front of the rails 14, 16, however in this embodiment of the invention the rails 14, 16 themselves are adapted to seat and retain the pales 18, and furthermore the pales 18 are bolted to the rails 14, 16, but using a more secure arrangement than a conventional fence. The pales 18 are of an angled section, defining a shallow “V”. Additionally, the pales 18 are slightly corrugated. Corresponding generally V-shaped apertures 28, 30 are provided in each rail 14, 16. The ends of each pale 18 may thus be passed through the apertures 28, 30 in the rails 14, 16, the pale ends 24, 26 passing through the apertures 28, 30 until beads or dimples 32, 34, pressed from the pales 18, engage the lower or upper surface of the horizontal arm 36, 38 of the respective rail 14, 16. In addition to a central rearwardly directed bead 32a (see FIG. 4) on each pale 18, two rearwardly directed dimples 32b, 32c are also provided towards the edges of the pale. Thus, when the rails 14, 16 are fixed between a pair of posts 12, the pales 18 are fixed and retained relative to the rails 14, 16.

The pales 18 are additionally secured to the rails 14, 16 by fasteners in the form of bolts 40 which pass through the vertical forward arms 42, 44 of the rails 14, 16 and the central portions of the pales 18. The bolts 40 are themselves secured by nuts 46 which are located in the centre of the “V” of the pale 18. The nuts 46 are of the form having an outer portion for engagement with a tightening tool such as a spanner or wrench, and an inner portion of a shape which is not easily gripped by a conventional tool. The two portions are frangibly connected such that when the nut is fully tightened and the operator continues to apply force to the outer portion of the nut, the outer portion will shear from the inner portion. The remaining inner portion of the nut 46 is further more relatively inaccessible with the “V” of the pale 18, and cannot readily be engaged and held by a tool. This contrasts with conventional fencing, in which the nut will be located, relatively exposed on the planar rear face of the vertical rail arms.

Furthermore, as the central portion of each pale 18 of this embodiment of the invention lies directly adjacent the rear face of the rail arms 42, 44, it is not possible to insert a conventional cutting tool or chisel into the tight gap 50 between the pale 18 and the rail arms 42, 44 to cut or shear the bolt 40. In addition, access to the gap 50 is only available from below and from the rear of the fence 10.

From the above description it will be apparent that the fence 10 is more secure than the fence described in GB 2256447 B due to the provision of the securing bolts 40. Further, the bolts 40 provide greater security than conventional bolted or riveted palisade fencing due to the inaccessibility of the securing nuts 46 and the relatively short and inaccessible section of bolt 40 which extends between the pales 18 and the rails 14, 16.

In other embodiments of the invention only a single dimple 32, 34 may be provided for engaging each rail, or another arrangement may be provided for restraining the pale 18 relative to the rails 14, 16, such as the arrangements described in GB 2256447 B.

In alternative aspects of the invention the dimples 32, 34 may be omitted, and the pales 18 located axially relative to the rails 14, 16 solely by bolts, rivets or the like. Welding or settable or curable materials may also be utilised to fix the pales 18 in the apertures 28, 30.

Reference is now made to FIG. 5 of the drawings, which illustrates a section of palisade fence 110 in accordance with a further embodiment of the present invention. This embodiment shares many features with the embodiments described above, however the pales 118 are secured to the rails 114, 116 by countersunk bolts 140. In particular, the bolt heads 141, which are circular and have a shallow rounded profile, are received in complementary recesses in the front face of the vertical forward arms 142, 144 of the rails 114, 116 and the central portions of the pales 118.

In one embodiment, the rail arms 142, 143, 144, 145 are 50 mm long and 6 mm thick. The bolt-receiving holes are 10 mm in diameter, while the bolt head-receiving recess is 2 mm deep and has a diameter of 21 mm. The bolts 140 are of mild steel.

The recessed bolt heads 141 are less vulnerable to attack by chisels and the like, and each bolt shaft is protected from attack by means of fine saws and the like.

In other embodiments the bolt may be protected by other structures or arrangements, for example beads of metal may be provided on the rails around the bolt holes, or a raised lip or ring may be provided to surround the bolt head, and restrict access to the bolt.

Claims

1. A palisade fence comprising:

support posts;

rails for extending between the posts; and

pales for mounting between the rails, the rails defining apertures for receiving the pales and the pales additionally being secured to the rails by fasteners.

2. A palisade fence of claim 1, wherein the rails comprise an L-section having a front vertical arm and a rear horizontal arm, the horizontal arm being apertured to receive the pales while the vertical arm receives the fastener.

3. A palisade fence of claim 2, wherein a rear face of the vertical arm of the rail and a front face of the pale through which the fastener passes are directly adjacent one another.

4. A palisade fence of claim 1, wherein the apertures are of complementary shape to the pales.

5. A palisade fence of claim 4, wherein the apertures are of complementary shape to end portions of the pales and the ends of the pales extend through the apertures, the end portions of each pale being provided with a projection spaced from an end of the pale such that only a selected length of each end portion passes through the associated aperture in the rail.

6. A palisade fence of claim 5, wherein the projection on each pale end portion comprises a bead pressed from the pale.

7. A palisade fence of claim 5, wherein the projection on each pale end portion is a welding bead.

8. A palisade fence of claim 5, wherein the projection is provided centrally of the pale.

9. A palisade fence of claim 5, wherein the projection is provided spaced from a centre line of the pale.

10. A palisade fence of claim 8, wherein at least one further projection is provided spaced from a centre line of the pale.

11. A palisade fence of claim 1, comprising three vertically spaced rails.

12. A palisade fence of claim 1, wherein the fastener is a bolt.

13. A palisade fence of claim 2, wherein the fastener passes through the vertical arm of the rail and through a central portion of the pale.

14. A palisade fence of claim 11, wherein the bolt is secured by a nut which engages with a rear face of the pale.

15. A palisade fence of claim 14, wherein the nut has an outer portion for engagement with a tightening tool, and an inner portion of a shape which is not easily gripped by a conventional tool, the two portions being frangibly connected.

16. A palisade fence of claim 14, wherein each pale has an angled section and the nut is located centrally of the pale.

17. A palisade fence comprising a plurality of pales, each pale having a face for location directly adjacent a face of a support rail and fasteners for securing the pales to the rail and passing through the faces.

18. A palisade fence of claim 17, wherein the rails comprise an L-section having a front vertical arm and a rear horizontal arm, the horizontal arm being apertured to receive the pales while the vertical arm receives the fastener.

19. A palisade fence of claim 17, wherein the fastener is a bolt secured by a nut which engages with a rear face of the pale.

20. A palisade fence of claim 19, wherein each pale has an angled section and the nut is located centrally of the pale.

21. A palisade fence of claim 2, wherein a surface of the vertical arm is recessed to receive a head of a fastener.

22. A palisade fence of claim 2, wherein a surface of the vertical arm is configured to restrict access to a head of a fastener passing therethrough.

23. A palisade fence comprising:

support posts;

rails for extending between the posts; and

pales for mounting between the rails, the pales being adapted to be secured to the rails by fasteners having heads, an outer surface of one of the pales and the rails being configured to restrict access to the fastener heads.