WO2004106843A2

WO2004106843A2 - Anti-explosion screen

Info

Publication number: WO2004106843A2
Application number: PCT/FR2004/001157
Authority: WO
Inventors: Charles Laubie
Original assignee: Sema
Priority date: 2003-05-26
Filing date: 2004-05-12
Publication date: 2004-12-09
Also published as: HUE033603T2; WO2004106843A3; FR2855606B1; EP1627201A2; EP1627201B1; FR2855606A1

Abstract

The invention relates to an anti-explosion screen comprising at least one panel (2, 3, 4) consisting of a blast shielding material, and a set of holding connectors (11) that are connected to the panel, on one side, by means of fixing points (12, 13), are can be fixed, on the opposite side, to at least one anchoring point (14, 15) located at a distance on one side of the screen. According to the invention, the lengths of the holding connectors (11) are adapted according to the positions of the anchoring points and corresponding fixing points, in order to maintain the screen in an upright position when it is subjected to an essentially horizontal force which distances it from the anchoring points and stretches the connectors.

Description

Improved explosion protection screen device

The present invention relates to an explosion protection screen, capable of mitigating the damage caused by the blast effect released by an explosion as well as the splinters projected during the explosion, that is to say the "fragmentation "

When a suspicious object is discovered in a public place and it is suspected that it is an explosive device, measures are generally implemented to evacuate the public, and to isolate the explosive device in view evacuation or defusing on site.

To isolate the explosive device, it is possible to use covers or screens made of splinter-proof materials resistant to the passage of splinters projected by the explosion.

However, these devices do not offer satisfactory protection. A cover placed on the explosive device may be lifted by the explosion, which limits the protection provided by the cover. A screen may be blown up by the explosion and may therefore not satisfactorily attenuate the blast effect, and not prevent the spread of splinters.

Furthermore, the implementation of these devices requires beforehand to detect the explosive device, then to have these protective elements, which requires a certain time taking into account the precautions which must be taken. However, during surprise terrorist attacks, for example when a suicide bomber unleashes a bomb in a public place, he does not have the time necessary to deploy these protective devices.

An object of the invention is to provide a screen device providing improved protection by absorbing the energy of a blast effect of an explosion and by stopping splinters, and which can also be discreet and deploy automatically during of an explosion. Such an explosion-proof screen device comprises at least one panel made of splinter-proof material and a set of retaining links connected on one side to the panel at fixing points and intended to be fixed on the side opposite to one or more points. anchor points located on one side of the screen, the lengths of the retaining links being adapted according to the positions of the anchor points and the corresponding fixing points to maintain the screen in the upright position when the screen undergoes a substantially horizontal force pushing it away from the anchor points, and that the connections are taut.

Preferably, the device comprises for a panel at least three retaining links connected to the panel at fixing points which are not aligned. Thus, a panel will be retained to pivot vertically and horizontally during the explosion. Low fixing points can be provided, for example on a lower edge of a panel and high fixing points, for example on an upper edge of a panel.

Preferably, the connections are flexible connections, of the strap or cable type. This allows, for more discretion, to arrange the screen in position with the flexible connections folded discreetly to avoid attracting attention, the flexible connections resting for example on the ground. In the event of an explosion in front of the screen on the side of the anchor points, the screen will be pushed back until the links are tightened, which will then keep it in the upright position. The flexible connections make it possible to provide anchoring points arranged at ground level, without a flexible connection connected to a fixing point located high on a panel being initially in a quasi-stretched position for more discretion.

The flexible connections can be provided with energy absorbers allowing an extension of the connection when it is subjected to a tensile force, together with an energy absorption. In one embodiment, a screen comprises a plurality of panels hinged together. This allows deployment of the screen, under the effect of the blast of an explosion, to increase a protective surface. In one embodiment, the screen device comprises at least one panel in the form of a rigid frame and a fabric of splinter-proof fabric arranged across the frame. By fabric in bursting fabric is meant a section of fabric of the type used for bulletproof vests and having a significant resistance as well as a significant energy absorption capacity to avoid tearing during an explosion. This type of fabric generally comprises fibers of the aramid type.

The fabric in splinter-proof fabric is, in one embodiment, fixed to the frame by means of a set of straps crisscrossed across the frame. The intertwined straps allow a resistant fixing of the canvas on the frame. Advantageously, the intertwined straps can be provided with energy absorbers.

A rigid frame is preferably provided with feet for holding the screen in a standing position when the flexible connections are not stretched. The legs of the frame can be fitted with wheels to facilitate a retraction of the screen by avoiding a tilting.

In one embodiment, a screen comprises a central splinter screen fixed by two opposite vertical edges between two uprights of two rigid frames of two side panels. The central splinter sheet can be initially folded between the side panels to deploy in the event of an explosion to increase a protective surface.

The present invention and its advantages will be better understood on studying the detailed description of embodiments taken by way of non-limiting examples and illustrated by the appended drawings, in which: - Figure 1 is a front view of a screen device with three panels according to one aspect of the invention;

- Figure 2 is a side view of a panel of the device according to Figure 1; - Figure 3 is a top view of the device according to the figure

1;

- Figure 4 is a side view of a device according to one aspect of the invention provided with flexible retaining links with anchor points to the ground, arranged in situation before an explosion; - Figure 5 is a side view of the device according to Figure 4 moved following an explosion;

- Figure 6 is a top view corresponding to Figure 5;

- Figures 7a and 7b are schematic views from above of a second embodiment of a device according to one aspect of the invention, in position before and after explosion;

- Figures 8a and 8b are views similar to Figures 6a and 6b of the device according to a variant, in the position before and after explosion; and - Figure 9 is a schematic top view of a group of devices according to the invention arranged in front of a point of passage preventively;

- Figure 10 is a side view of a flexible connection of the strap type provided with an energy absorber. In FIG. 1, a screen device 1 according to the invention comprises vertical splinter-proof panels, here three in number, including a central panel 2, a first side panel 3 and a second side panel 4.

The screen device 1 comprises a rigid articulated frame, for example of the metallic tubular type, comprising vertical uprights 5, here four in number and arranged side by side, two adjacent uprights 5 being connected on the one hand to their ends upper by a top cross 6 and on the other hand at their lower ends by a bottom cross 7, to form a rigid frame consisting of two adjacent uprights 5 two cross 6, 7. Here, three adjacent rigid frames are thus formed at using the four uprights 5, the uprights 5 located between two adjacent frames being used in common for these two adj acent frames. The fasteners of the lower 7 and upper 6 crosspieces with the uprights 5 are articulated along the vertical axis of the uprights 5 to allow rotation along a vertical axis of a rigid frame relative to the adjacent rigid frame, as indicated by the arrow P (figure 3) in order to modify a screen arrangement.

Each panel 2, 3, 4 is composed of a rigid frame as described and a canvas 8 made of splinter-proof fabric arranged across the rigid frame. Each fabric 8 is stretched in the corresponding frame while being held by vertical and horizontal straps 9 stretched between the uprights 5 and the crosspieces 6, 7 forming the frame, being intertwined.

Coverages can be provided between the fabrics 8 of the adjacent frames for better protection. It is also possible to provide a single canvas 8 disposed obstructing all the frames simultaneously, the canvas nevertheless being fixed on the intermediate uprights 5 to allow adequate folding of the screen.

As can best be seen in Figure 2, where only one panel is shown from the side, the panels have a small thickness, which contributes to the discretion of the device.

Referring to Figures 1 and 3, the uprights 5 of the panels 2, 3 4 are provided with feet 10. The screen device 1 further comprises retaining links 11, here in the form of straps or cables, fixed d 'one side on fixing points 12, 13 provided on the panels 2, 3, 4, and on the other side on anchor points 14, 15, here two in number. The anchor points 14, 15 are provided in the form of rings fixed firmly in the ground. Upper fixing points 12 are provided in the form of fixing lugs integral with the upper ends of the uprights 5, and low fixing points 13 are provided in the form of fixing lugs integral with the lower ends of the uprights 5. Each of the points fixing 12, 13 of the first side panel 3 and of the central panel 2 is connected to a first anchoring point 14 by a retaining link 11, and each of the fixing points 12, 13 of the second side panel 4 and of the central panel 2 is connected to a second anchoring point 15. The fixing points of the central panel 2 are therefore each connected simultaneously to the two anchoring points 14,

15. There are therefore a total of twelve retaining links 11.

Alternatively, one could provide a single anchor point, or more anchor points. For example, one could provide an anchor point associated with each upright 5 of the screen. The arrangement of the retaining links between the uprights 5 and the anchor points can be modified, to provide more or less retaining links depending on the force that can be supported by each of the retaining links.

In all cases, the lengths of retaining links will be adapted so that the panels 2, 3, 4 of the screen are kept in the upright position when the screen is pushed in a direction opposite to the anchoring points 14, 15 by the effect. of breath from an explosion.

The anchor points can be located on the ground, but one could also provide certain anchor points in height when possible, for example in a hall of a building.

For discreet positioning of the screen, it is advantageous to provide ground attachment points and flexible retaining links, as will be better understood in the study of FIGS. 4 to 6, where the numerical references to elements similar to those of previous figures have been repeated. In FIG. 4, a high flexible retaining link 11a is fixed on one side to an anchoring point 14 situated on the ground and on the other side to a high fixing point 12 situated at an upper end of a screen panel 2 seen from the side. A flexible low retaining link 11b is fixed on one side to the anchoring point 14 and on the other side to a low fixing point 13 located at a lower end of the panel 2.

The upper link l ia is longer than the low link 11b. Initially, the panel 2 is located at a distance from the anchoring point 14 less than the length of the bottom link 11b. The panel 2 is close enough to the anchoring point 14 so that the upper link 11b is not stretched and is arranged vertically along the panel 2 and horizontally on the ground up to the anchoring point 14.

The low link 11b and the high link l ia are not stretched. An intermediate part of the high links ia and low 11b is folded carefully and discreetly at the foot of the panel 2.

When an explosion occurs at an explosion point 16, located on the same side of the screen as the anchor point 14, a blast effect propagates in all directions, as illustrated by the arrows f. The blast effect, reaching panel 2, develops efforts. The result of these efforts on the panel, illustrated by the arrow F, is mainly horizontal. The screen as a whole, and the panel 2 in particular is therefore pushed from the side opposite to the anchoring point 14. The panel 2 moves back until it reaches the position illustrated by FIG. 5 in which the flexible high and low connections l ia , 11b are stretched. The length of the connections is adapted so that the panel 2 subjected to the blast effect is kept upright substantially vertically, in order to prevent the panel 2 from lying down since it would no longer protect the part situated on the opposite side from explosion. .

In the case where the high fixing point 12, the low fixing point 13 and the anchoring point 14 are located in the same vertical plane, the lengths of the high and low links l ia, 11b must substantially respect, with the vertical distance between the high fixing points and the low fixing points, the relation of

Pythagoras of right triangles. Of course, with other provisions of the anchor points and fixing points, the connection lengths must respect different relationships.

During an explosion, the panel initially close to the anchoring point 14 for a discreet arrangement of the high link l ia, moves back over a distance which depends on the relative length of the high and low links l i a, 11b.

By way of example, in the case of the panel in FIG. 5, with a panel 2 m high and a low link 3 m long, the high link has a length of 3.6 m. The panel may initially be placed approximately 1.6 m (or 3.6 m - 2 m) from anchor point 14.

In the event of an explosion, the panel will retreat 1.4 m.

Provision could be made for the panel 2 subjected to an explosion to be able to tilt back a few degrees relative to the vertical position (for example 0 to 5 °), to deflect a blast effect.

In FIG. 6, before an explosion, the screen 1 with three panels 2, 3, 4, shown in dotted lines, is placed in a position where the side panels 3, 4 are slightly folded. Following the explosion at explosion point 16, the screen moves back to a second position, shown in solid lines. Taking into account the length of the flexible retaining links initially provided, the screen 1 moves back while opening.

It will be noted that the panels 2, 3, 4 are each held by two flexible connections with fixing points offset horizontally to avoid rotation along a vertical axis of the panel so that it is held in position facing the explosion for better protection. In general, each panel will preferably be retained by at least three flexible connections with fixing points arranged on the triangle panel, that is to say that they are not aligned. In Figure 7a, a screen 1 is provided with five hinged panels. In the initial position, for more discretion, the screen 1 is arranged so that the central panels of the screen 1 are folded over each other.

As illustrated in FIG. 7b, during an explosion, the screen 1 undergoing the blast effect of the explosion and retained by the retaining links 11 will deploy completely, thus increasing a protective surface.

In FIG. 8a, a screen 1 comprises two independent side panels 3, 4, and a central fabric 17 disposed between the panels 3, 4 while being connected by its vertical edges opposite the panels. The central fabric 17 is folded to have a length greater than the distance separating the panels 3, 4 in the initial position. The panels 3, 4 and the central fabric are connected by flexible retaining links 11 to one of the anchoring points 14. As illustrated in FIG. 8b, during an explosion, the panels are separated by the breath of the explosion and the central canvas

17 unfolds and inflates by adopting a profile which depends on the lengths chosen for the retaining links 11.

In FIG. 9, a set of screen devices according to one aspect of the invention are implemented in front of a crossing point.

18 which may be an entrance to a building.

A first screen 20 is arranged opposite the entrance, and second and third screens 21, 22 are arranged in staggered arrangement. If a person carrying a bomb crosses the crossing point 18 and detonates his bomb at the explosion point 23 which he has reached, the first screen protects the zone A located behind the first screen 20, the second and third screens 21 , 22 offering additional protection, especially if the more advanced terrorist is laterally offset relative to the first screen.

Screens 20, 21, 22 can be discreetly placed in public places by integrating with the decor without shocking by their presence. This helps not to attract the attention of a terrorist or to worry the public. The screens can be covered with decorative elements. The screens are arranged as a precaution before an explosion and therefore provide effective protection in the event of a terrorist attack. Furthermore, thanks to the retaining links, the screens will be kept in the upright position, thus protecting the public behind the screens. The panels, made up of frame and splinter screens are light, which facilitates the arrangement and installation of screens. In addition, the screens retained by flexible connections from a limited number of ground anchors allows easy and discreet installation of the screens.

To improve the behavior of the screens, provision can be made for the webbing holding straps on the frames (FIG. 1) as well as the retaining links to be provided with an absorber.

To do this, and as can be seen in FIG. 10, provision may be made, for example, for a strap 24 to have an intermediate portion 25 made up of three sections of similar length, a central section 25a being folded over a first lateral section. 25b, the other lateral section 25c being itself folded over the central section 25a on the side opposite to the first lateral section 25b. In other words, the intermediate portion 25 is folded back on itself, forming a zone of triple thickness, the sections 25a, 25b, 25c being thus maintained by any suitable means, here a seam 26. A portion thus forming is obtained. reserve of length for the strap 24 and maintained by seams 26. When a force is exerted on a panel, the strap 24, which is a retaining strap or a strap for holding a splinter fabric, is subjected to a stress of tension symbolized by arrows F2. Yes the effort is sufficient, the seams 26 are torn off by absorbing energy and the strap 24 relaxes. This allows better absorption of the energy produced by a blast effect on a panel, at the level of the straps for holding a splinter-proof fabric and / or at the level of the panel retaining straps disposed between the panel and a point. of hanging. One or more absorption zones may be provided on a strap.

If the strap is attached to its ends by sewing, provision may be made for a seam 26 of the intermediate portion 25 which is less resistant than the end seam so that the seam 26 of the intermediate portion 25 yields first and fulfills its role of absorber energy.

In the case of flexible retaining links provided in the form of metal cables, provision may be made, for example, for portions provided with intermediate springs to absorb energy.

Thanks to the invention, an anti-explosion screen device is finally obtained which makes it possible, in the event of an explosion, to keep the screen in an upright position to prevent the screen from being laid down by the blast of the explosion. The screen can be installed quickly and easily, and can be integrated into a decor without attracting attention.

Claims

1. Explosion-proof screen device comprising at least one panel (2, 3, 4) made of splinter-proof material, characterized in that it comprises a set of retaining links (11) connected on one side to the panel at fixing points (12, 13) and intended to be fixed on the side opposite to one or more distant anchoring points (14, 15) situated on one side of the screen, the lengths of the retaining links (11) being adapted as a function of the positions of the anchor points and of the corresponding fixing points to maintain the screen in the upright position when the screen undergoes a substantially horizontal thrust force moving it away from the anchor points, and the connections are taut.

2. Device according to claim 1, characterized in that it comprises for a panel at least three retaining links

(11) connected to the panel at fixing points which are not aligned.

3. Device according to any one of claims 1 or 2, characterized in that the retaining connections are flexible connections, of the strap or cable type.

4. Device according to claim 3, characterized in that flexible connections are provided with energy absorbers (25, 26) allowing an extension of the connection when it is subjected to a tensile force, together with an absorption of energy.

5. Device according to any one of the preceding claims, characterized in that it comprises a plurality of panels hinged together.

6. Device according to any one of the preceding claims, characterized in that it comprises at least one panel in the form of a rigid frame (5, 6, 7) and of a fabric of splinter-proof fabric ( 8) arranged across the frame.

7. Device according to claim 6, characterized in that a fabric of splinter-proof fabric (8) is fixed to a frame by means of a set of straps (9) crisscrossed across the frame.

8. Device according to claim 7, characterized in that the intertwined straps are provided with energy absorbers (25, 26).

9. Device according to any one of the preceding claims, characterized in that it comprises a central splinter screen (16) fixed by two opposite vertical edges between two uprights of two rigid frames of two side panels (3, 4 ).