FR3035139A1 - INTRUSION RETARDER BARRIER GRID - Google Patents

Abstract

The present invention relates to a fence bar (10) fence, said grid (10) comprising a plurality of bars (1) hollow interconnected by cross members (2), at least some of said bars (1) housing at least one rod (7) rotatably mounted along an axis substantially parallel to the longitudinal axis of the corresponding bar (1).

Description

FIELD OF THE INVENTION The field of the invention is that of the design and manufacture of fences.

The invention relates more particularly to physical protection devices placed around protected sites to prevent access or at least to delay it. 2. PRIOR ART The surroundings of protected sites, such as power generation sites or other sites, are generally closed by means of fences in order to prevent access. These fences include mostly rigid grid panels, composed of vertical and horizontal solid metal son, secured to the ground by means of poles.

In order to dissuade the candidates to the instruction on a protected site, one seeks to increase the time necessary for the passage through the fence securing the access to this one. For this purpose, several fences are generally arranged one behind the other.

Indeed, an intrusion candidate equipped with a portable electric or thermal grinder must cut with his tools the fences one after the other to enter the protected site. Thus, the more the number of fence to cut will be important, the longer the time required for the intrusion will be high.

This technique is quite effective in that increasing the time of intrusion on a site contributes to increase the deterrent aspect of the fence. This technique, however, has disadvantages. In particular, the establishment of a series of fences behind each other to secure a site is long. In addition, the multiplication of fences generates a significant consumption of raw materials. In the end, the technique of reducing the number of fences in order to slow down the intrusion on a protected site is a strong deterrent, but involves significant material and labor costs. OBJECTIVES OF THE INVENTION The object of the invention is in particular to provide an effective solution to at least some of these various problems. In particular, according to at least one embodiment, an object of the invention is to provide a fence which allows, in at least one embodiment, to significantly increase the time of intrusion on a site. In particular, the object of the invention is, according to at least one embodiment, to provide such a fence, the passage time of which is longer than that required for passage through a rigid grid panel. In particular, an object of the invention is to provide, in at least one embodiment, such a fence whose implementation allows to increase the time of intrusion without requiring the establishment of a succession of fences one behind the other, or at least reducing the number of successive fences required. The invention also aims to provide, in at least one embodiment, such a fence that is simple and / or quick to put in place. Another object of the invention is, according to at least one embodiment, to provide such a fence which is simple design. 4. PRESENTATION OF THE INVENTION For this, the invention proposes a fence bar fence, said grid comprising a plurality of hollow bars interconnected by cross members, at least some of said bars housing at least one rod mounted rotatably along an axis substantially parallel to the longitudinal axis 25 of the corresponding bar. Thus, the invention proposes an original solution which consists in accommodating in at least some of the bars of a barred grid at least one rod mounted free to rotate along the corresponding bar. In this way, when an individual begins to cut a bar 30 of a bar grating housing a rod free in rotation by means of a grinder, after the outer wall of the bar has been cut, the cutting disc of the grinder comes into contact with the rotating free rod and causes it to rotate. It is thus very difficult to cut the rotating rod rotatably housed in the bar. The time required to cut a passage in the fence to allow an individual to pass on the other side of it is thus greatly increased. The technique according to the invention thus makes it possible to considerably increase the passage time through a fence, as compared to a conventional rigid grid panel fence, and thus to dissuade the candidates from the intrusion while limiting the number of fences. successive to implement to secure a site. The technique according to the invention thus also makes it possible to simplify the installation of fences securing access to protected sites, and possibly to reduce the necessary raw material. According to one conceivable characteristic, said rod or stems extend in the corresponding bar essentially all along it. This reinforces the inviolability of a bar over its entire length.

According to one conceivable characteristic, some rods extend over a portion of the length of the corresponding bar. It is thus possible to reinforce bars in vulnerable areas, especially at man-made height, and not higher in order to improve safety while reducing raw material costs.

According to one conceivable characteristic, some of said bars house two rods movably rotated one beside the other along axes substantially parallel to the longitudinal axis of the corresponding bar. Increasing the number of rods further increases security.

According to one conceivable characteristic, the two rods mounted in the same bar have different lengths. It is thus possible to reinforce bars in vulnerable areas, especially at man-made height, and not higher in order to improve safety while reducing raw material costs.

According to one conceivable characteristic, guide rings are interposed between said rods and the corresponding bar.

3035139 4 It thus facilitates the rotation of the rods which makes it all the more difficult their cutting. According to one conceivable characteristic, the guide rings of two rods mounted in the same bar are arranged in staggered rows.

This prevents them from being in contact with each other which could be detrimental to the rotation of the rods. According to a possible characteristic, said rods are solid and cylindrical. This maximizes their rotation while making them difficult to cut. According to one conceivable characteristic, the distance between two consecutive bars is less than 110 millimeters. This makes it more difficult for an individual to pass through the grid. According to one conceivable characteristic, the concentration of crosspieces is greater in a lower region of said barred grid. This reinforces the inviolability of the grid especially in an area easily accessible by man, which contributes to improving safety while reducing raw material costs. According to one conceivable characteristic, a barred grid according to the invention comprises means for detecting vibrations. It is thus possible to be informed that an intrusion attempt, which generates vibrations, is in progress. According to one conceivable characteristic, a bar grid according to the invention comprises two lateral columns, each of said lateral columns 25 being integral, on either side of said bar grid, said sleepers. It thus constitutes a one-piece assembly easy to handle and install and particularly robust. 5. List of Figures Other features and advantages of the invention will appear on reading the following description of particular embodiments, given by way of simple illustrative and non-limiting examples, and the appended drawings among which: FIG. 1 illustrates a perspective view of an exemplary bar grating according to the invention; FIG. 2 illustrates a front view of the barred grid illustrated in FIG. 1; FIG. 3 illustrates a side view of the barred grid illustrated in FIGS. 1 and 2; - Figure 4 illustrates a partial longitudinal sectional view of a bar grid rod containing two rods according to an embodiment of the invention; - Figure 5 illustrates a cross-sectional view of a bar grid rod containing two rods according to an exemplary embodiment of the invention. 6. Description of particular embodiments 6.1. Architecture In relation to FIGS. 1 to 5, there is shown a bar grid according to the invention. As shown in these figures, such a bar grid 10 comprises a plurality of bars 1 arranged substantially parallel to each other. In this embodiment, the bars 1 extend vertically. They could in a variant extend horizontally. The bars 1 here have the shape of hollow tubes made of metallic material. Other suitable materials could alternatively be used. The section of the bars 1 is here rectangular. In variants, it could for example be circular or other. The bars 1 are interconnected by means of crosspieces 2. The crosspieces 2 consist of flat iron elements welded to the bars 1 to form a barred grid. They could be made in other materials including metallic adapted.

The density of sleepers 2, i.e. their number, is greater in a lower region I of the bar grid. In particular, it will be more important approximately on the lower half of the barbed wire or more generally at height of man, or about two meters.

The distance between two consecutive bars 1 is preferably less than 110 millimeters. Preferably, it will be less than 75 millimeters. The ends of the crosspieces 2 are connected to the right side posts 3 and 5 left 4. They are for example secured by welding or otherwise. The lateral columns 3, 4 could alternatively be reported and do not form a one-piece assembly with the grid bar 10. The posts 3, 4 extend below the barred portion of the grid.

The lower cross member 2 optionally carries projecting members 6 towards the underside of the barred grid. Supports 5 barbed wire 50 are secured to the upper end of each pole 3, 4. They allow the establishment of barbed wire 50 arranged spirally above the barred portion of the grid. These brackets of barbed wire are optional. In this embodiment, each bar 1 houses two rods 7. The rods 7 extend inside the bars 1 corresponding along axes substantially parallel to the longitudinal axis of the bar 1. The rods 7 are here metal bars full circular section preferably made of stainless steel. They could be made of other materials including metal Each rod 7 is mounted "crazy" inside the bar 1 corresponding. In other words, it is free to rotate along its longitudinal axis. Guide rings 8 are interposed between each rod and the corresponding bar 1 25. These rings 8 are distributed substantially uniformly between the rods 7 and the bars 1 along the length of the rod 7. They are preferably made of a damping material such as an elastomer, silicone or other. The rings 8 of two rods 7 of the same bar 1 will preferably be staggered so as not to come into contact with each other, as shown in FIG. 4. In this embodiment, each Bar 1 houses two rods 7. In variants, the bars 1 can accommodate a single rod 7 or more than two rods 7. In variants, only some bars 1, for example a bar 1 of two, 3035139 7 can accommodate one or several rods 7. Each rod 7 extends all along the corresponding bar 1. In a variant, one of the two rods 7 housed in the same bar 1 may be shorter than the other. In particular, the shorter of the rods 7 may extend approximately to the lower half of the length of the bar 1, or more generally to the height of man, or about two meters. In variants, the bars 1, or only some of them, may contain only one rod 7 or more than two rods 7 which will extend all along or only over a portion of the length of the bar 1 10 corresponding. The rods 7 may for example have a diameter of between 10 and 15 millimeters. The guide rings 8 may be constituted by O-rings whose inner diameter will be substantially equal to that of the rods 7 and the diameter 15 of the twist may be of the order of three millimeters. The adjustment between a ring 8 and the corresponding rod 7 will preferably be slippery. The number of guide rings 8 per rod 7 may for example be of the order of two to four per meter. The barred portion of the grid may have a height of about five meters and the posts extend below the barreaudées part about one meter. According to one variant, the bar grid 10 may comprise one or more vibration sensors arranged for example inside a certain bar 1 or post 3, 4 or at any other suitable location. 6.2. Implementation Several bar grids 10 according to the invention can be implemented to achieve a fence for example to secure access to a protected site. The rods 7 are mounted inside the bars 1 directly at the factory. In order to build a fence, excavations are dug at the location where the fence is to be located. Barred grids 10 according to the invention are deposited within these excavations one after the other in a contiguous manner by resting them on the base of their lateral columns 3, 4. The excavations are then filled with concrete. The lower part of the posts 3, 4 and the protruding elements 6 of the lower cross member 5 are then embedded in the concrete. The bar gratings 10 are optionally further secured in pairs by suitable fastening means such as bolts or other. Barbed wires 50 are optionally attached to the supports 5 provided for this purpose.

The vibration sensors, preferably installed on the grid at the factory are optionally connected to means of communication with an analysis center. 6.3. Operation When a candidate intrudes on the cutting of a bar 1 15 by means of an electric or thermal grinder, after cutting the wall of the bar 1, the cutting disc of the grinder comes into contact with the or rods 7 housed in the bar 1. These rods 7, free in rotation in the bar 1, are rotated by the cutting disc. The cutting of the rod 7 is then impossible or at least very slow. Under the effect of the rotation of the rods, ejections of the grinder are observed outside the bar and rapid degradation of the cutting disc. It is thus impossible to cross by cutting the bar grid for example in less than three minutes equipped with an electric grinder and in less than five minutes equipped with a heat grinder.

If the candidate manages to cut the rod 7, it falls by gravity, so it is again necessary to cut it to hope to provide an opening in the grid 10. Providing that some rods 7 are not not extend over the entire length of the bar 1, for example only on a lower portion 30 corresponding substantially to the height of a man, maximizes the protection in an area easily accessible by a man. This reduces costs while offering enhanced protection. The implementation of the guide rings 8 facilitates the free rotation of the rods 7 inside the bars 1 as well as to avoid vibrations. Providing that the bars 1 are spaced a distance of less than 110 millimeters makes it possible to prevent a candidate from intruding from being able to pass the tool, in particular the grinder, with which he intends to cut the grating. 10 on the other side of the grid 10. This is thus obliged to attack the cut of a bar 1 only on the side where it is located without being able to go around it, which makes it more difficult to cut the bar 1 and lengthens the time needed to use it. The fact of providing a greater density of cross-member 2 at the lower part of the barred portion of the grid 10, in particular at man's height, makes it possible to limit the risk that a candidate for intrusion will succeed in opening there a opening to pass on the other side of the grid 10. The fact of forming in one piece the grid bar 10 and the posts 3, 4 to form a one-piece assembly makes the grid bar 15 10 more resistant including blows of ram. This also facilitates the assembly of the fence. Similarly, the fact of providing protruding elements 6 towards the ground on the lower crossbar 2, and intended to be embedded in the concrete, makes the grid bar 10 more resistant to water hammers.

The presence of the rods 7 in the bars 1 makes it possible to increase the resistance to torsion of the bars 1. It is thus more difficult for a candidate to intrude to maneuver a passage through the grid 10 by moving apart bars 1.

Claims (4)

REVENDICATIONS1. Bar grid (10) closing, said grid (10) comprising a plurality of bars (1) hollow interconnected by cross members (2), characterized in that at least some of said bars (1) house at least one rod (7) rotatably mounted along an axis substantially parallel to the longitudinal axis of the corresponding bar (1). 2. Bar grating according to claim 1, characterized in that the or said rods (7) extend in the bar (1) corresponding substantially all along thereof. 3. Grid according to claim 1, characterized in that some rods (7) extend over a portion of the length of the bar (1) corresponding. 4. Bar grating according to any one of claims 1 to 4, characterized in that some of said bars (1) house two rods (7) rotatably mounted next to each other along axes essentially parallel to the longitudinal axis of the bar (1) corresponding. S. Bar grating according to claim 4, characterized in that the two rods (7) mounted in the same bar (1) have different lengths. 6. Bar grating according to any one of claims 1 to 5, characterized in that guide rings (8) are interposed between said rods (7) and the bar (1) corresponding. 7. Bar grating according to claims 4 and 6, characterized in that the guide rings (8) of two rods (7) mounted in the same bar (1) are arranged in staggered rows. 8. Bar grating according to any one of claims 1 to 7, characterized in that said rods (7) are solid and cylindrical. 9. Barred grating according to any one of claims 1 to 8, characterized in that the distance between two bars (1) consecutive is less than 110 millimeters. 10. Bar grating according to any one of claims 1 to 9, characterized in that the concentration of sleepers (2) is greater in a lower region of said bar grating (10). 11. Barred grating according to any one of claims 1 to 10, characterized in that it comprises means for detecting vibrations. 12. Bar grating according to any one of claims 1 to 11, characterized in that it comprises two lateral columns (3, 4), each of said lateral columns (3, 4) being integral, on both sides said grid bar (10), said sleepers (2).