Road impact attenuator

Abstract

The present invention relates to a road impact attenuator (1) for absorbing energy from a frontal impact of a vehicle, comprising: - a first guardrail (9) supported at its proximal end (10) by a first post (8); - a second guardrail (11) supported at its proximal end (12) by a second post (13), wherein the first guardrail (9) and the second guardrail (11) are arranged in series and coupled in slidable manner along a longitudinal direction (L); - a connector (15) rigidly connecting the first guardrail (9) at its distal end (14) and the second guardrail (11) at its proximal end (12), wherein said connector (15) comprises a portion (16) rigidly connected to the first guardrail (9) and crossing the second guardrail (11) in a direction transversal to the longitudinal direction (L), such that, as a consequence of said vehicle frontal impact against the road impact attenuator (1), the first guardrail (9) tends to slide relative to the second guardrail (11) along the longitudinal direction (L) and said crossing portion (16) cuts the second guardrail (11).

Description

[0001] ROAD IMPACT ATTENUATOR

[0002] Field of the invention

[0003] The present invention relates to the field of road safety and to the use of road barriers.

[0004] The present invention relates, in particular, to an impact attenuator for attenuating the impact energy of a vehicle against a road barrier.

[0005] Prior art

[0006] Road safety is ensured by numerous devices including road barriers, which are installations capable of ensuring that a vehicle maintains the lane in the event of a collision or loss of control.

[0007] These road barriers allow vehicles to be kept in the lane but at the same time offer a structure suitable for absorbing the collisions to which they are subjected. Such collisions can result from a frontal impact or from a lateral impact of the vehicle, where the major problems for frontal impacts can be found on fast-moving roads or motorways.

[0008] The frontal impact is particularly critical at junctions, where the road forks into two branches. At the junction, in fact, the barriers of the two branches join at the union of the branches themselves, forming an acute angle which behaves like an anvil capable of causing greater damage than a simple lateral impact against the barrier.

[0009] In addition to the greater damage caused by the aforementioned anvil, even greater damage is caused, both to the vehicle and to its occupants, by the deceleration resulting from the impact, such as to determine, for example, the crushing and / or breakage of the internal organs of the occupants themselves which in many cases is lethal. Numerous protective devices are known which are suitable for defining impact attenuators capable of attenuating the impact energy of a vehicle against a road barrier.

[0010] US6 116805 describes a compressible type impact attenuator, in particular comprising a plurality of deformable elements defined by suitable cerclages.

[0011] US4674911 describes an impact attenuator of the compressible and reusable type defined by a plurality of air chambers arranged consecutively.

[0012] Patent Application IT no. 102015902336347 describes a compressible type impact attenuator comprising coaxial and telescopic impact attenuating elements, mutually sliding along a longitudinal sliding axis. These impact attenuating elements comprise a cavity which compresses during the reciprocal axial sliding following an impact, from a first position of maximum axial extension to a second position of minor axial extension to allow the absorption of energy through the progressive extraction of the air from the cavity itself.

[0013] All the above-mentioned devices require the presence of some dissipating material / device which results in a structural complexity of the barrier and in high production costs. It would be therefore desirable to have an impact attenuator able to guarantee a high energy absorption while maintaining low production costs and structural simplicity.

[0014] Summary of the invention

[0015] The object of the present invention is therefore to provide a road impact attenuator able to minimize the aforementioned drawbacks.

[0016] Particularly, the object of the present invention is to provide a road impact attenuator able to guarantees a controlled deceleration in the absorption of impact shock which is structurally simple and, consequently, involves low production costs.

[0017] This object is achieved by a road impact attenuator according to the claim 1.

[0018] The dependent claims define possible advantageous embodiments of the invention. Brief description of the figures

[0019] To better understand the invention and appreciate its advantages, some of its nonlimiting exemplary embodiments will be described below, referring to the attached figures, in which:

[0020] - Figure 1 shows a partially in transparency side view of a road impact attenuator according to a possible embodiment of the invention;

[0021] - Figure 2 shows a schematic aerial view of the road impact attenuator in Figure 1;

[0022] - Figure 3 shows a sectional view, along plane A-A of the road impact attenuator in Figure 1.

[0023] Detailed description of the invention

[0024] For the purpose of the present description and of the appended claims, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term "about". Also, all ranges include any combination of the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein.

[0025] For the purpose of the present description and of the appended claims, the words “a” or “an” are used to describe elements and components of the invention. This is done merely for convenience and to give a general sense of the invention. In this description and claims should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.

[0026] The present disclosure, in at least one of the aforementioned aspects, can be implemented according to one or more of the following embodiments, optionally combined together.

[0027] With reference to the attached Figures, an impact attenuator for use in roads, suitable for attenuating the frontal impact energy of a vehicle against a road barrier, is indicated as a whole by the numeral 1. The road impact attenuator 1 is particularly suitable to be positioned at junctions, where the road forks into two branches.

[0028] The impact attenuator 1 is designed to allow the reduction of the impact energy generated by the deceleration of a vehicle against the impact attenuator 1 itself, until it reaches a level such as not to cause fatal damage to the human body.

[0029] The impact attenuator 1 extends along a longitudinal direction L from a frontal end 2, where the frontal impact with a vehicle may occur, to a rear end (not shown in the Figures), where a crash barrier, for example of the guardrail type, can start.

[0030] The impact attenuator 1 comprises a frontal module 3 and a central module 4 connected in series. Each module comprises energy absorbing elements arranged in at least one row, preferably in a plurality of rows arranged in parallel. In the embodiment depicted in the Figures 2 and 3, the impact attenuator 1 comprises two parallel rows of energy absorbing elements. In the following, just for the sake of simplicity, reference will be made to a single row, as depicted in Figure 1.

[0031] The frontal module 3 comprises a frontal guardrail 5 supported by at least two posts 7, 8 in turn anchored to the ground. The frontal guardrail 5 is connected to a frontal element 6 where a frontal impact with a vehicle may occur.

[0032] With reference to the central module 4, it comprises a first guardrail 9 supported by and connected at its proximal end 10 with a first post, which can be, in particular, the same post 8 supporting the frontal guard rail 5. The central module 4 further comprises a second guardrail 11 supported and connected at its proximal end 12 by a second post 13 anchored to the ground. The first 9 and the second 11 guardrails are arranged in series and coupled in slidable maimer, preferably by their shape. As can be seen for example in Figure 3 (where the proportions are enlarged for the sake of clarity), the first 9 and second 11 guardrails have matching waved shaped forming a slide coupling. The first guardrail 9 at its distal end 14 partially overlaps the second guardrail 11 at its proximal end 19, thereby forming an overlapping zone. Preferably, the first guardrail 9 is positioned in outer position with respect to the second guardrail 11.

[0033] It is to be observed that the first guardrail 9 is not directly supported by the second post 13, which is directly connected only to the second guardrail 11. On the contrary, the impact attenuator 1 comprises a connector 15 rigidly connecting the first 9 and the second guardrails 11 at the overlapping zone.

[0034] Such a connector 15 comprises a portion 16 rigidly connected to the first guardrail 9 and crossing the second guardrail 11 in a direction transversal, in particular perpendicular, to the longitudinal direction L. In an embodiment, such a connector 15 comprises a threaded fastener 17, such as a bolt or the like, forming the above- mentioned crossing portion 16, transversally crossing the second guard rail 11 and coupled, for example screwed, with a coupling plate 18 rigidly connected to the first guardrail 9 at the distal end 14. For example, the threaded fastener 17 can be inserted into the second guardrail 11 from the outside and be connected to the coupling plate 18, which partially envelops the second guardrail 11 at the proximal end 12, on the inner side, as depicted for example in the Figure 3. It is observed that the coupling plate 18, due to its configuration, cooperates in maintaining the slide coupling among the first 9 and the second 11 guardrails.

[0035] In case of a frontal impact at the frontal end 2, first the frontal module 4 is affected and the frontal guardrail 5 is deformed and tends to slide towards the first guardrail 9, supported by the second post 8, which tends to bend. Then, the first guardrail 9 of the central module 4 tends to move towards the second guardrail 11 sliding relative the latter. However, the first guardrail 9 is locked at its distal end 14 to the proximal end 12 of the second guardrail 12 by the connector 15, where only the second guardrail 11 (not the first guardrail 9) is supported by the second post 13. Accordingly, the crossing portion 16, rigidly connected to the first guardrail 9 by the coupling plate 18, is pushed by the first guardrail 9 and tends to cut the second guardrail 11 along the longitudinal direction L. Surprisingly, the Applicant has found that this phenomenon, based on very simplified elements (the parts of the connector 15) is suitable to absorb the kinetic energy as required by the impact attenuator 1, without the need of any further energy absorbing element.

[0036] The impact attenuator 1 may comprise one or more further couples of first 9 and second 11 guardrails as described with reference to the central module 4, connected in series, where the second guardrail of a couple forms the first guardrail of the following couple. In this maimer, the impact attenuator can sequentially absorb energy.

[0037] It will be therefore apparent to the skilled person that the road impact attenuator 1 according to the invention allows an efficient energy absorption due to a vehicle frontal impact using few and cheap components.

[0038] To the described embodiments of the road impact attenuator the skilled person, in order to meet specific contingent needs, may make numerous additions, modifications, or substitutions of elements with functionally equivalent ones, without, however, departing from the scope of the attached claims.

Claims

Claims1. A road impact attenuator (1) for absorbing energy from a frontal impact of a vehicle, comprising:- a first guardrail (9) supported at its proximal end (10) by a first post (8);- a second guardrail (11) supported at its proximal end (12) by a second post (13), wherein the first guardrail (9) and the second guardrail (11) are arranged in series and coupled in slidable manner along a longitudinal direction (L);- a connector (15) rigidly connecting the first guardrail (9) at its distal end (14) and the second guardrail (11) at its proximal end (12), wherein said connector (15) comprises a portion (16) rigidly connected to the first guardrail (9) and crossing the second guardrail (11) in a direction transversal to the longitudinal direction (L), such that, as a consequence of said vehicle frontal impact against the road impact attenuator (1), the first guardrail (9) tends to slide relative to the second guardrail (11) along the longitudinal direction (L) and said crossing portion (16) cuts the second guardrail (11).

2. The road impact attenuator (1) of claim 1, wherein the first guardrail (9) and the second guardrail (11) have matching waved shaped forming a slide coupling.

3. The road impact attenuator (1) of claim 1 or 2, wherein the first guardrail (9) at its distal end (14) partially overlaps the second guardrail (11) at its proximal end (12).

4. The road impact attenuator (1) of any of the preceding claims, wherein said connector (15) comprises a coupling plate (18) rigidly connected to the first guardrail (9) at its distal end (14), said crossing portion (16) being connected to said coupling plate (18).

5. The road impact attenuator (1) of any of the preceding claims, wherein said crossing portion (16) comprises a threaded fastener.

6. The road impact attenuator (1) of the preceding claim, wherein said threaded fastener is inserted from outside across the second guardrail (11) and connected to the coupling plate (18).

7. The road impact attenuator (1) of any of the preceding claims, further comprising a frontal element (6) and at least one frontal guardrail (5) connected to the frontal element (6) and supported by at least two posts (7, 8), wherein said first guardrail (9) is connected in series with said at least one frontal guardrail (5), wherein said first post (8) corresponds to one of said at least two posts (7,8) supporting the at least one frontal guardrail (5).

8. The road impact attenuator (1) of any of the preceding claims, comprising one or more couples of said first (9) and second (11) guardrails arranged in series in one or more parallel rows.

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