FR2899251A1 - DEVICE FOR BRAKING A BODY IN MOTION - Google Patents

Abstract

The invention relates to a device for braking a moving body, comprising a carrier element adapted to be fixed by a first part and adapted to be connected by a second part, either to a means for braking said moving body, or directly to the latter, which device comprises at least one energy dissipation loop, provided with at least one fuse connected to two fixing points of the carrier element, the length of the fuse being, when the device is at rest, substantially lower at the length of the carrier element between the two attachment points, so that when said carrier member is subjected to a force due to the moving body, said fuse absorbs all or part of the energy generated by the body in motion. movement, in which the carrier element is, at the point of attachment, provided with a hooking element, for connecting the fuse to the carrier element with this element hooking.

Description

DEVICE FOR BRAKING A BODY IN MOTION DESCRIPTION

  The present invention relates to a device for braking a moving body, comprising a carrier element adapted to be fixed by a first part and adapted to be connected by a second part, or to a means for braking said moving body, or directly to the latter, which device comprises at least one energy dissipation loop, provided with at least one fuse connected to two attachment points of the carrier element, the length of the fuse being, when the device is at rest substantially less than the length of the carrier element between the two attachment points, so that when said carrier member is subjected to a force due to the moving body, said fuse absorbs all or part of the generated energy by the body in motion. The present invention is especially adapted for stopping rock falls, on sloping ground, and in particular, a dynamic barrier for stopping rock falls, in which load-bearing elements have dissipation loops. energy. Protective barriers against falling rocks are generally made of a net held by posts across the predictable path of the stones on sloping ground. The net consists of metal cables, for example stainless steel, whose frames can slide relative to each other at the nodes and mechanically linked by caliper cable clamps. The net is supported by guy wires connected to poles whose feet can be fixed or articulated at their foundation in the ground, the poles being stabilized by cables anchored in the ground upstream and downstream.

  During an impact by a block, part of the energy of the block is absorbed by deformation of the net at the level of the cable ties and the poles at their base and the elastic deformations also reduce the initial energy.

  However, this type of barrier is not always sufficient to stop in all circumstances the largest blocks likely to hit the slopes. Solutions have therefore been adopted to improve the effectiveness of barrier barriers. It was thus planned to attach the net on the posts by means of springs. But the improvement is limited because of the low possible elongation of the springs.

  A device according to the introduction is known from French patent FR 9705880. The device according to this patent is provided with the carrier elements in the form of cable. On this cable, between two attachment points, fusible cables are attached. These fusible cables are connected to the carrier cable, so that, at rest, the length of the fuse cable is substantially less than the length of the carrier cable between said attachment points. When the braking device according to this patent is used, the force of a moving body is transmitted from the carrier cable to the fuse cable. The fuse cable is then stretched under the effect of the tensile force exerted on the carrier cable, elongates and eventually breaks. This means that the fuse cable is able to absorb at least a portion of the kinetic energy of the moving body to slow down said moving body.

  The assembly of the carrier cable and the fuse cable, according to FR9705880, is realized by means of sliding or locking sleeves. This assembly requires to be performed using a hydraulic press in the workshop. A disadvantage of such an assembly is that it only allows the use of cable type materials and does not vary the materials used to manufacture the carrier element and the fuses. Another disadvantage lies in the fact that after the first use and the deterioration of the entire system that results, it is necessary to proceed to the change of the system in its entirety. The assembly must then be transported to the workshop to repair the damaged fuses.

  In addition, the fixing of the fuse cable on the carrier cable, by means of a hydraulic press, results in the weakening of the carrier cable. For all these reasons, an object of the invention is to provide a moving body braking device, according to the introduction, allowing the replacement of damaged fuses in situ, without the need to transport the braking device in the workshop and prepare said device for a next use. The main object of the invention is therefore a moving body braking device, comprising a carrier element adapted to be fixed by a first part and adapted to be connected by a second part, or to a means for braking said moving body, or directly to the latter, which device comprises at least one energy dissipation loop, provided with at least one fuse connected to two fixing points of the carrier element, the length of the fuse being, when the device is at rest, substantially less than the length of the carrier element between the two attachment points, so that when said carrier member is subjected to a force due to the moving body, said fuse absorbs all or part of the energy generated by the moving body, wherein said carrier member is, at the attachment point, provided with a hooking member, for connecting the fuse to the carrier member using this snap element.

  Thanks to the presence of the fastening elements on the attachment points, the user can take advantage of this attachment element to connect the fuses to the carrier element.

  Another technical effect is that, thanks to the presence of the attachment elements, it is possible to vary the nature of the materials used to manufacture the carrier element and the fuses.

  According to the invention, it is possible for the fastening elements to have the shape of a loop.

  According to a preferred embodiment, it is possible for the carrier element to comprise, at least over a part of its length, a chain, and for said hooking element to be formed by a link in this chain.

  The presence of a loop or the presence of links greatly facilitates the possibility of connecting fuses to the carrier element. This means that after a first use of the braking device according to the invention, the user can easily hang new fuses on the carrier element.

  It does not need to carry the device to a place where there are special tools to connect these new fuses on the carrier. According to the invention, it is possible that the fuses are made of metal. Alternatively, it is possible that the fuses are made of an elastic material such as rubber.

  It should be understood that for the invention it is possible to use all materials that can absorb all or part of the energy generated by the moving body. In addition, it should be noted that in this text, the braking device is provided with a fuse. The fuse word is used to indicate the possibility of absorbing energy, for example by plastic or elastic deformation of the fuse.

  According to the invention, it is not forced that the fuse is broken during the braking of the moving body. It is quite possible for the fuse to undergo elastic deformation and, after use, to return to its original position.

  According to the invention, it is possible for at least a first and second fuse to be connected to a first and a second attachment point of the carrier member. In addition, it is possible for the carrier element to comprise at least a first and a second energy dissipation loop.

  According to the invention, it is possible that the means for braking said bodies is a net. Thus, it is possible that said net is disposed between two posts anchored in the ground and held with the aid of the carrier element.

  The objects, objects and features of the invention will appear more clearly on reading the following description, with reference to the drawings in which: FIG. 1 shows a cross-section of a moving body braking device according to one embodiment of the invention,

  FIG. 2 is a plan view of the device illustrated in FIG.

  FIG. 3 represents a part of the carrier element, provided with a first and a second fastening element, connected by a fuse,

  FIG. 4 represents the carrier element according to FIG. 3, after the rupture of the fuse,

  FIG. 5 shows a carrier member, provided with a first and a second engaging member, wherein the engaging members are connected to a first and second fuse, in parallel, FIG. a carrier element, seen from a first and a second energy dissipation shield, placed in series,

  FIG. 7 shows a chain-type carrier element, in which the links are used for fastening fuses,

  FIG. 8 shows, in detail, a string fuse, FIG. 9 shows a fuse-equipped net before use and,

  Figure 10 shows the net according to Figure 9 after use.

  Figure 1 shows the cross-section of a braking device of a moving body 1, installed along a contour line in a terrain 2.

  The braking device 1 is provided with a net 10, secured to the ground 2 by means of posts 11, anchored to the ground. The net 10 is in principle metal. The net 30 is held by carrying elements 3 and stays 4, anchored to the ground by means of support plates 12 and anchors. The carrier member 3 is provided with one or more energy dissipation loops 20 for absorbing the energy of a moving body. Examples for making energy dissipation loops 20 are shown in Figures 3-8.

  The carrier members 3 may, as in Example 40 illustrated in FIG. 1, form a triangle by means of two pulleys 13, 14 or recesses located at the bottom and at the top of the posts 11.

  The braking device of a moving body 1, according to FIG. 1, is represented by a plan view 10 in FIG. 2. FIG. 2 shows the fixing of the stays 4 between the posts 11 and the support plates 12 .

  The operation of the moving body braking device 1 according to the invention is as follows:

  in the event of falling stone blocks, the dissipation of kinetic energy of such a stone takes place, firstly, thanks to the particular mesh 20 of the net 10, which makes it possible, during the impact, to slide the cables forming the frame.

  The carrier elements 3 which can, as in the example illustrated in FIG. 1, form a triangle by means of the two pulleys 13, 14 or recesses situated at the bottom and at the top of the posts 11, receive, after the impact of the block, most of the kinetic energy acquired by the stones and must therefore be equipped with energy dissipation mechanism. These mechanisms 30 are provided with a form of energy dissipation loop 20, comprising fuses as mentioned below, and which can be, according to particular embodiments of the invention, loops provided with fuses in parallel or loops mounted in series.

  A first embodiment of a power dissipation loop 20 is shown in FIG. 3. The loop comprises a carrying cable 3 provided with a first attachment element 31 and a second element of FIG. hanging :: 32, to connect, in between, a fuse 40. The attachment elements are intended to be intrinsic elements to the carrier element. The length of the fuse 40 is substantially less than the length of the carrier element between the attachment means 31, 32. This part of the carrier element is indicated with the number 33. When the moving body braking device according to the invention is used, a force is exerted on the carrier element 3. The tensile force relative to the impact of the moving body, on the carrier element 3, is indicated by an arrow in FIG. The fuse element 40 extends and absorbs a portion of the kinetic energy of the moving body until it breaks, illustrated in FIG. 4, by the fusible element 40 between the elements 31 and 32. .

  It is possible to mount fuse elements in parallel, as shown in FIG. 5, or in series, as shown in FIG.

  According to the invention, it is provided that between the elements 31 and 32 and the carrier element 3, there is a first fuse 41 and a second fuse 42. This makes it possible to adapt the maximum amount of energy capable of to be absorbed by the energy dissipation loop 20 '.

  Figure 7 shows a carrier element 3 'which is in the form of a chain. The fact that the carrier element 3 'has the form of a chain, facilitates the mounting of the fuses 43, 44, 45, 46. The fuses 43-46 are each mounted between two links of the chain 3'. The carrier member 3 'and the fuses 43-46 together form an energy dissipation loop 20 "with four fuses which, one by one, can dissipate a certain amount of energy from a moving body.

  FIG. 8 shows the carrier element 3 'with, between two links, a fuse 50 comprising 3 rings 51, 52, 53 which together form a chain-type fuse between two links of the carrier element.

  The load-bearing elements used in the moving body braking device and used in the dynamic stone fall arrest barrier are generally metal cables, preferably steel, with a diameter of between 10 and 25 mm. Fuses must have a lower yield strength than the load cell. As shown below, the fuses may be metal, steel, or plastic or composite having mechanical parameters equivalent to those of steel, fire-resistant and ultraviolet radiation to which they are constantly exposed.

  In fact, all materials, capable of absorbing some energy, can be used as fuses. It should be noted that fuses can be reused. This means that the fuse, for example rubber, undergoes an elastic deformation to slow the moving body. After using the device according to the invention, it is possible for the fuses to return to their initial position and be ready for a new use of the braking device of the moving body.

  In the present text, reference is made particularly to barriers to protection against falling rocks. It is important to note that the device according to the invention can also be used in the following non-exhaustive examples in air, on land, on and in water, for braking a moving body, by example a rock, a rolling machine, flying or floating or a living being.

  In FIG. 9, there is shown a thread 50 provided with several fuses 51. In FIG. 9, only part of the thread 50 is shown.

  The fuses 51 are fixed in the mesh of the net 50. They are mounted in such a way that the mesh of the net 50, in a position of the net at rest, is substantially lower than the mesh of the net in the case where the fuses do not exist. .

  In FIG. 10, the net 50, according to FIG. 9, is shown after the impact of a moving body. Fig. 10 again shows the net with a much larger mesh size than that shown in Fig. 9. The fuses 51 were broken and, upon breaking, absorbed energy to slow the moving body. According to the invention, the fuses 51 of the net 50 may be in the form of a loop, the fuse being, for example, a certain length of cable formed in a loop and placed in the mesh of the net. Such fuses can be put into the net, in situ, without the need to be transported to the workshop and thus prepared the net for future use.

  According to Figure 10, the fuses 51 are dispersed in the mesh of the net 50, irregularly. The fuses can be arranged in any way depending on the use of the net 50.

Claims (9)

  1. A device for braking a moving body (1), comprising at least one carrier element (3) adapted to be fixed by a first part and adapted to be connected by a second part, or at least one means for braking said body in motion, or directly to the latter; which device comprises at least one energy dissipation loop (20), provided with at least one fuse (40) connected to two fixing points of the carrier element, the length of the fuse (40) being, when the device is at rest, substantially less than the length of the carrier element between the two attachment points (33), so that when said carrier member (3) is subjected to a force due to the moving body, said fuse ( 40) absorbs all or part of the energy generated by the moving body, characterized in that said carrier member (3) is, at the point of attachment, provided with a fastening element (31, 32, 31 ', 32 '), for connecting the fuse (40) to the carrier element (3) with the aid of this hooking element (31, 32, 31', 32 ').   2. Device according to claim 1, characterized in that said hooking element (31, 32, 31 ', 32') has the shape of a loop.   3. Device according to claim 1 or 2, characterized in that the carrier element (3) comprises, at least over a part of its length, a chain, said attachment element (31, 32, 31 ', 32' ) being formed by a link of this chain.   4. Device according to one of claims 1 to 3, characterized in that the fuse (40) is metal.   5. Device according to one of claims 1 to 3, characterized in that the fuse (40) is of elastic material such as rubber.   6. Device according to one of the preceding claims, characterized in that at least a first (41) and a second (42) fuses are connected between a first and a second attachment points of the carrier member (3).   7. Device according to one of the preceding claims, characterized in that the carrier element (3) comprises at least a first (20) and a second (20) energy dissipation loops.   8. Device according to one of the preceding claims, characterized in that the means for braking said body is a net (10).   9. Device according to claim 8, characterized in that said thread (10) is disposed between two posts (11) anchored in the ground and held with the support member (3).