High Energy Impact Absorbing Post

The present invention relates to an impact absorbing post for collision protection, more specifically for high energy impact collision protection. The present invention also relates to a method for assembling such an impact absorbing post and to a use of the impact absorbing post and/or the method for collision protection resilient to an impact of at least 12 kJ.

Impact absorbing posts for collision protection are known and are especially used to reduce the risk of harm to humans or to avoid damage to infrastructure or valuable goods. Such impact posts are for instance used in parking lots, warehouses or industrial facilities, where you have mixed traffic of vehicles and humans or where you have heavy duty vehicles, such as forklift trucks or lorries, that could cause substantial damage to a building, to infrastructure or stored goods.

A first type of known impact absorbing posts has a metal base member, on which a vertical tube is bolted. The tube is made from an elastically deformable material. However, this type impact absorbing posts is not suited for absorbing a high energy impact, for instance an impact of more than 3 kJ. During collision the tube bends and the metal base member cuts in the tube, damaging the tube. High tensions occur in the tube around the bolts, resulting in further damage and very often in a failure of the impact absorbing post.

A second type of known impact absorbing posts also has a metal base member, on which a first elastically deformable tube is pressed and bolted. Foams are attached to the surfaces of the first tube to absorb part of the impact. A second elastically deformable tube is placed over the first tube and the foams. This type of impact absorbing post cannot withstand high energy impact collisions either. During collision, the second tube will slide over the first tube. The second tube deforms only limited, resulting in that just a small part of the energy of the impact is absorbed by the second tube and the foams. Most of the energy is absorbed by the first tube, often resulting in failure of the first tube near the metal base member.

U.S. Pat. No. 4,522,530 discloses a self-erecting roadway marking post. The marking post is able of being repetitively bent through an angle of ninety degrees and of returning to an upright straight position. Consequently, this post is not suited as an impact absorbing post.

DE 297 22 257 describes a traffic beacon with a tubular shaft and an adapter attached to the shaft for fastening the traffic beacon to a base plate. The attachment must be flexible enough to allow the traffic beacon to lay flat when the traffic beacon is run over by a vehicle, without launching the base plate in the air. Again, this makes the traffic beacon unsuited for use as an impacted absorbing post.

FR 2 616 818 concerns a mast for supporting signalization panels. The mast has the advantage that it does not tear off in the event of a collision. However, the mast will deform plastically at the base, which is unwanted for an impact absorbing post.

The present invention aims to resolve at least some of the problems and disadvantages mentioned above.

The present invention and embodiments thereof serve to provide a solution to one or more of above-mentioned disadvantages. To this end, the present invention relates to an impact absorbing post for collision protection according to claim.

This impact absorbing post is advantageous as it can absorb high energy impacts of more than 3 kJ due to the use of a primary impact member and at least one inner impact member. Due to the connecting members, the primary impact member will not slide over the at least one inner impact member, forcing the primary impact member to absorb its part of the impact energy and avoiding that the impact energy is mainly absorbed by the at least one inner impact member, resulting in a failure of the at least one inner impact member. Because the at least one inner impact member has a shorter length than the primary impact member, the primary impact member will deform elastically first and only when the primary impact member is bent sufficiently and touches the at least one inner impact member, the at least one inner impact member will start deforming elastically and absorbing energy. The impact absorbing post becomes gradually stiffer when deforming elastically. The placement of the at least one inner impact member inside the connection profile is especially advantageous to avoid that the connection profile cuts at the inside of the primary impact member, resulting in structural damage to the impact absorbing post and finally in failure of it. While bending, the primary impact member will touch mainly the at least one inner impact member and not or only in a limited way the connection profile.

Preferred embodiments of the impact absorbing post are shown in any of the claimsto.

A specific preferred embodiment relates to an invention according to claim.

This embodiment is especially beneficial when having a long impact absorbing post, where the high energy impact of more than 3 kJ is expected to occur at a relative high level above the surface. This could result in buckling of the impact absorbing post. Simply increasing the height of the at least one inner impact member would make the impact absorbing post stiffer, avoiding the buckling of the impact absorbing post, but it would also reduce the elastic deformation of the impact absorbing post and consequently the absorption of the impact energy. The impact energy will be transferred to a large extent to the base member. This could result in that the base member cracks, the impact absorbing post comes off the surface and/or that the surface is damaged. In any of these cases, the impact absorbing post failed. By adding an anti-buckling member, that is placed inside the at least one inner impact member and has a longer length than the at least one inner impact member, buckling of the impact absorbing post is avoided, while the impact absorbing post can still absorb the high energy of the impact. Because the impact is at a high level, a level above the at least one inner impact member, and because the anti-buckling member is not in contact with the primary impact member, the primary impact member will as before deform elastically and absorb the energy of the impact first. Before the primary impact member bends too much and risks to buckle, the primary impact member touches the anti-buckling member and a part of the impact energy is transferred to the anti-buckling member. With further elastic deformation of the primary impact member, the at least one inner impact member is also getting elastically deformed, and the high energy of the impact at a high level above the surface is successfully absorbed in the whole impact absorbing post.

In a second aspect, the present invention relates to a method according to claim.

This method is very beneficial because it provides an impact absorbing post that can withstand impact with high energy, even higher than 3 kJ, without failure of the impact absorbing post. The primary impact member, the base member nor the at least one inner impact member will be damaged on impact. The impact absorbing post remains firmly fixed to the surface, without damaging the surface. In the eventuality that a member of the impact absorbing post is damaged, the impact absorbing post can be easily dismantled and the damaged part can be simply replaced, this in contrast to an impact absorbing post where a tube is pressed on the base member. The method also allows a flexible assembly of the impact absorbing post depending on the expected impact energy that should be withstood and the level above the surface where the impact can be expected, by simply changing for instance the number of inner impact members and the length of the inner impact members.

Preferred embodiments of the method are shown in any of the claimsto.

In a third aspect the present invention relates to a use according to claim.

The use as described herein provides an advantageous effect that a collision protection can be provided that is resilient to an impact of at least 12 kJ, that can be easily repaired in the eventuality of damage and that can be adapted in a flexible way depending on the expected impact energy and the level above the surface where the impact can be expected.

Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions are included to better appreciate the teaching of the present invention.

As used herein, the following terms have the following meanings:

“A”, “an”, and “the” as used herein refers to both singular and plural referents unless the context clearly dictates otherwise. By way of example, “a compartment” refers to one or more than one compartment.

“Comprise”, “comprising”, and “comprises” and “comprised of” as used herein are synonymous with “include”, “including”, “includes” or “contain”, “containing”, “contains” and are inclusive or open-ended terms that specifies the presence of what follows e.g. component and do not exclude or preclude the presence of additional, non-recited components, features, element, members, steps, known in the art or disclosed therein.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order, unless specified. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within that range, as well as the recited endpoints.

Whereas the terms “one or more” or “at least one”, such as one or more or at least one member(s) of a group of members, is clear per se, by means of further exemplification, the term encompasses inter alia a reference to any one of said members, or to any two or more of said members, such as, e.g., any ≥3, ≥4, ≥5,≥6 or ≥7 etc. of said members, and up to all said members.

Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

In the context of this document, extending substantially perpendicular to a plane, for instance a surface or a plate, means that the angle between a direction wherein something extends to the plane and the plane is 90°±15°, preferably 90°±10°, more preferably 90°±5° and even more preferably 90°±3°.

In the context of this document, substantially parallel means that two directions make an angle of at most 15°, preferably at most 10°, more preferably at most 5° and even more preferably at most 3°.

In the context of this document, when referring to the energy that an impact absorbing post can withstand, the impact absorbing post has been tested according to the standard PAS13:2017.

In a first aspect, the invention relates to an impact absorbing post for collision protection.

In a preferred embodiment the impact absorbing post comprises a base member for mounting the absorbing post on a surface, a primary impact member for absorbing an impact of a collision, connecting members for connecting the primary impact member to the base member and at least one inner impact member.

The base member comprises a bottom plate and a hollow connection profile for connecting the primary impact member to the base member using the connecting members. The base member is preferably made of metal, more preferably steel. The bottom plate is intended to be placed with one side on the surface. The surface is for instance a concrete floor of a warehouse or an asphalt surface of a parking lot. The bottom plate comprises holes for attaching the base member to the surface by using bolts, screws, anchors or other suitable means. The bottom plate comprises at least four holes, preferably at least five holes and more preferably at least six holes. The holes are preferably equally distributed around the centre of the bottom plate. Optionally, the bottom plate comprises an extra hole in the center to avoid plastic deformation of the bottom plate during impact. The connection profile is firmly fixed to the bottom plate. Preferably the connection profile is welded to the bottom plate. The connection profile extends along a longitudinal direction. The connection profile extends substantially perpendicular to the bottom plate. This means that the longitudinal direction of the connection profile is substantially perpendicular to the bottom plate and when installed on a surface substantially perpendicular to the surface. The connection profile is a hollow profile.

The primary impact member is a hollow profile made from a polymer, preferably a polyolefin, such as polyethylene (PE), polypropylene (PP) and polybutylene (PB), and more preferably polypropylene (PP). The primary impact member extends in a longitudinal direction. The primary impact member extends substantially perpendicular to the bottom plate. This means that the longitudinal direction of the connection profile and the longitudinal direction of the primary impact member are substantially parallel.

The connection profile is placed inside the primary impact member. Consequently, the connection profile cannot be impacted directly during a collision. The connection profile is protected by the primary impact member against collision. The primary impact member is connected to the connection profile by use of the connecting members. Non-limiting examples of connecting members are screws, bolts, bolts and nuts, rivets, wedges, . . .

The at least one inner impact member is a hollow profile made from a polymer, preferably a polyolefin, such as polyethylene (PE), polypropylene (PP) and polybutylene (PB), and more preferably polypropylene (PP). The material may be different from or the same as the material from which the primary impact member is made. Preferably the material is the same as the material from which the primary impact member is made. This is beneficial when recycling the impact absorbing post.

The at least one inner impact member extends in a longitudinal direction. The at least one inner impact member extends substantially perpendicular to the bottom plate. This means that the longitudinal direction of the connection profile, the longitudinal direction of the primary impact member and the longitudinal direction of the at least one inner impact member are substantially parallel. The at least one inner impact member has a shorter length than the primary impact member. Said length is measured perpendicularly from the bottom plate to an opposing end of the at least one inner impact member, respectively an opposing end of the primary impact member. This means that in the case of multiple inner impact members, every inner impact member has a length shorter than the length of the primary impact member. The at least one inner impact member has a longer length than the connection profile. Said length is measured perpendicularly from the bottom plate to an opposing end of the at least one inner impact member, respectively an opposing end of the primary impact member. This means that in the case of multiple inner impact members, every inner impact member has a length longer than the length of the connection profile. The at least one inner impact member is placed at the bottom plate inside the connection profile. As a result, the connection profile surrounds the at least one inner impact member at the side of the bottom plate and the at least one inner impact member protrudes from the connection profile.

An impact absorbing post according to the current embodiment is advantageous as it can absorb high energy impacts of more than 3 kJ due to the use of a primary impact member and at least one inner impact member. Due to the connecting members, the primary impact member will not slide over the at least one inner impact member, forcing the primary impact member to absorb its part of the impact energy and avoiding that the impact energy is mainly absorbed by the at least one inner impact member, resulting in a failure of the at least one inner impact member. Because the at least one inner impact member has a shorter length than the primary impact member, the primary impact member will deform elastically first and only when the primary impact member is bent sufficiently and touches the at least one inner impact member, the at least one inner impact member will start deforming elastically and absorbing energy. The impact absorbing post becomes gradually stiffer when deforming elastically. The placement of the at least one inner impact member inside the connection profile is especially advantageous to avoid that the connection profile cuts at the inside of the primary impact member, resulting in structural damage to the impact absorbing post and finally in failure of it. While bending, the primary impact member will touch mainly the at least one inner impact member and not or only in a limited way the connection profile.

In a preferred embodiment the impact absorbing post comprises at least one outer impact member. The at least one outer impact member is a hollow profile made from a polymer, preferably a polyolefin, such as polyethylene (PE), polypropylene (PP) and polybutylene (PB), and more preferably polypropylene (PP). The material may be different from or the same as the material from which the primary impact member and/or the at least one inner impact member are made. Preferably the material is the same as the material from which the primary impact member and the at least one inner impact member are made. This is beneficial when recycling the impact absorbing post. The at least one outer impact member extends in a longitudinal direction. The at least one outer impact member extends substantially perpendicular to the bottom plate. This means that the longitudinal direction of the connection profile, the longitudinal direction of the primary impact member, the longitudinal direction of the at least one inner impact member and the longitudinal direction of the at least one outer impact member are substantially parallel. The at least one outer impact member has a shorter length than the primary impact member. The at least one outer impact member has a longer length than the at least one inner impact member. Said lengths are measured perpendicularly from the bottom plate to respectively an opposing end of the at least one outer impact member, an opposing end of the primary impact member and an opposing end of the at least one inner impact member. This means that in the case of multiple outer impact members, every outer impact member has a length shorter than the length of the primary impact member and that every outer impact member has a length longer than the length of the at least one inner impact member, meaning in the case of multiple inner impact members, that every outer impact member has a length longer than the length of every inner impact member. The at least one outer impact member is placed inside the primary impact member. The at least one outer impact member is placed at the bottom plate outside the connection profile. As a result, the at least one outer impact member surrounds the connection profile at the side of the bottom plate.

This embodiment is especially advantageous when having a very high impact energy of for instance more than 10 kJ. For such an impact, it is necessary to have an impact absorbing post that is strong, but can still deform elastically to absorb the energy of the impact. Simply strengthening the primary impact member would reduce the possibility to deform elastically and the ability to absorb the impact energy, increasing the risk of damage to the primary impact member and failure of the impact absorbing post. The at least one outer impact member is beneficial because the primary impact member can still deform elastically easily and absorb energy due to the shorter length of the at least one outer impact member, but it will not break because it is more quickly supported by the at least one outer impact member than by the at least one inner impact member due the absence of the connection profile between the primary impact member and the at least one outer impact member.

In a further embodiment the at least one outer impact member is a series of subsequent outer impact members. Every subsequent outer impact member is placed inside a previous outer impact member. Every subsequent outer impact member has a shorter length than the previous outer impact member. Said lengths are measured perpendicularly from the bottom plate to an opposing end of the outer impact members. Subsequent outer impact members may, but do not have to have a same thickness. This embodiment has the same advantages as described before. This embodiment is additionally beneficial because the stiffness of the impact absorbing post is increasing towards the bottom plate, causing a elastic deformation of the impact absorbing post that is spread along the length of the impact absorbing post and reduces the elastic deformation near the base member. Because the elastic deformation is spread along the length of the impact absorbing post, the total displacement of the impact absorbing post in the direction of the impact is more limited compared to a situation where the elastic deformation is mainly concentrated in a single zone of the impact absorbing post, increasing the safety behind the impact absorbing post. Changing the thickness of subsequent outer impact members gives more flexibility to spread the elastic deformation of the impact absorbing post along its length.

In a preferred embodiment the impact absorbing post comprises an anti-buckling member. The anti-buckling member is a hollow profile made from a polymer, preferably a polyolefin, such as polyethylene (PE), polypropylene (PP) and polybutylene (PB), and more preferably polypropylene (PP). The material may be different from or the same as the material from which the primary impact member, the at least one inner impact member and/or the at least one outer impact member are made. Preferably the material is the same as the material from which the primary impact member, the at least one inner impact member and when present the at least one outer impact member are made. This is beneficial when recycling the impact absorbing post. The anti-buckling member extends in a longitudinal direction. The anti-buckling member extends substantially perpendicular to the bottom plate. This means that the longitudinal direction of the connection profile, the longitudinal direction of the primary impact member, the longitudinal direction of the at least one inner impact member, the longitudinal direction of the at least one outer impact member when present and the anti-buckling member are substantially parallel. The anti-buckling member has a shorter length than the primary impact member. The anti-buckling member has a longer length than the at least one inner impact member. The anti-buckling member has a longer length than the at least one outer impact member when present. Said lengths are measured perpendicularly from the bottom plate to respectively an opposing end of the anti-buckling member, an opposing end of the primary impact member, an opposing end of the at least one inner impact member and an opposing end of the at least one outer impact member. This means that in the case of multiple inner impact members, every inner impact member has a length shorter than the length of the anti-buckling member and in the case of multiple outer impact members, every outer impact member has a length shorter than the length of the anti-buckling member. The anti-buckling member is placed inside the at least one inner impact member.

This embodiment is especially beneficial when having a long impact absorbing post, where the high energy impact of more than 3 kJ is expected to occur at a relative high level above the surface. This could result in buckling of the impact absorbing post. Simply increasing the height of the at least one inner impact member or the at least one outer impact member when present would make the impact absorbing post stiffer, avoiding the buckling of the impact absorbing post, but it would also reduce the elastic deformation of the impact absorbing post and consequently the absorption of the impact energy. The impact energy will be transferred to a large extent to the base member. This could result in that the base member cracks, the impact absorbing post comes off the surface and/or that the surface is damaged. In any of these cases, the impact absorbing post failed. By adding an anti-buckling member, that is placed inside the at least one inner impact member and has a longer length than the at least one inner impact member and the at least one outer impact member when present, buckling of the impact absorbing post is avoided, while the impact absorbing post can still absorb the high energy of the impact. Because the impact is at a high level, a level above the at least one inner impact member and the at least one outer impact member when present, and because the anti-buckling member is not in contact with the primary impact member, the primary impact member will as before deform elastically and absorb the energy of the impact first. Before the primary impact member bents to much and risks to buckle, the primary impact member touches the anti-buckling member and a part of the impact energy is transferred to the anti-buckling member. With further elastic deformation of the primary impact member, the at least one outer impact member when present and the at least one inner impact member are also getting elastically deformed, and the high energy of the impact at a high level above the surface is successfully absorbed in the whole impact absorbing post.

In a preferred embodiment the at least one inner impact member is a series of subsequent inner impact members. Every subsequent inner impact member is placed inside a previous inner impact member. Every subsequent inner impact member has a shorter length than the previous inner impact member. Said lengths are measured perpendicularly from the bottom plate to an opposing end of the inner impact members. Subsequent inner impact members may, but do not have to have a same thickness. This embodiment has similar advantages as described before for the at least one outer impact member, being a series of subsequent outer impact members. This embodiment has the additional advantage that there is typically more space available inside the connection profile than between the primary impact member and the connection profile, because the primary impact member is preferably placed close to the connection profile to avoid a big translation of the primary impact member when a collision occurs. This allows typically to have more subsequent inner impact members than subsequent outer impact members, resulting in a better spread of the elastic deformation along the impact absorbing post. Changing the thickness of subsequent inner impact members gives more flexibility to spread the elastic deformation of the impact absorbing post along its length.

In an embodiment the connection profile, the primary impact member and the at least one impact member have a same shape for a cross-section, wherein the cross-section is made transverse to the longitudinal direction of respectively the connection profile, the primary impact member and the at least one impact member. The cross-sections of said members have each a centre. Said centres are preferably superimposed seen in a direction transverse to the bottom plate. This embodiment is beneficial for transferring impact energy between said members, independent of a direction wherefrom an impact originates, because it is possible to place said member in such way that a distance between one of said members to an adjacent member of said members is along its circumference equal. Preferably the cross-section is circular.

In a further embodiment the connection profile, the primary impact member, the at least one impact member and the anti-buckling member have a same shape for a cross-section, wherein the cross-section is made transverse to the longitudinal direction of respectively the connection profile, the primary impact member, the at least one impact member and the anti-buckling member. This embodiment has the same advantages as described before.

In a preferred embodiment the impact absorbing post comprises a connector for connection of a horizontal rail to the impact absorbing post. The connector is suited for sliding the horizontal rail in or over the connector, for placing the horizontal rail in the connector or another suitable way of connecting the horizontal rail to the connector. The horizontal rail may be firmly attached to the connector, but does not need to. The connector extends substantially perpendicular to the impact absorbing post through the primary impact member. Preferably the primary impact member comprises an opening for allowing the connector to extend through the primary impact member. The connector may be firmly attached to the primary impact member, but does not need to. Preferably the connector is not firmly attached to the primary impact member. The impact absorbing post comprises an anti-buckling member, as described in previous embodiments. The anti-buckling member extends through the connector. The connector preferably comprises an opening for allowing the anti-buckling member to extend through the connector. The connector may be firmly attached to the anti-buckling member, but does not need to. Preferably the connector is not firmly attached to the anti-buckling member. A connector that is not firmly attached to the anti-buckling member and to the primary impact member allows easier elastic deformation of the impact absorbing post. This embodiment is beneficial to provide collision protection between impact absorbing posts. The connector can be loosely attached because it is held in a direction transverse to the bottom plate by the primary impact member and it is held in a direction transverse to the longitudinal direction of the anti-buckling member by the anti-buckling member itself.

In a preferred embodiment the connecting members are at least two bolts and nuts. The bolts are traversing from a first side of the impact absorbing post through the impact absorbing post to a second opposing side of the impact absorbing post. A first bolt is substantially perpendicular to a second bolt. This embodiment is beneficial because the bolts are not only connecting the primary impact member, but also the at least one inner impact member and when present the at least one outer impact member and the anti-buckling member. Two substantially perpendicular bolts are advantageous to have a balanced distribution of the energy of the impact over the connecting members, independent of a direction wherefrom an impact originates. The bolts have at least a size M8, preferably at least M10 and even more preferably at least M12. A bigger size is advantageous to avoid that the primary impact member tears around the bolt on impact.

In a preferred embodiment the at least one inner impact member and when present the at least one outer impact member are formed as separate hollow profiles. This means that every inner impact member and when present every outer impact member is a separate profile. Every inner impact member is slidable relative to an adjacent inner impact member and when present every outer impact member is slidable relative to an adjacent outer impact member. This is beneficial for elastic deformation of the impact absorbing post and absorbing the energy of an impact.

In an alternative embodiment the at least one inner impact member and the at least one outer impact member are formed as a single profile with a stepped inside. The single profile has a recess to receive the connection profile. When present, the anti-buckling member may or may not be integrated in the single profile. Preferably the anti-buckling member is integrated in the single profile. The single profile is advantageous for easy production and assembly of the impact absorbing post due to the reduced number of steps to assemble the impact absorbing post. However, some flexibility is lost concerning easy adaptation of dimensions of the at least one inner impact member and the at least one outer impact member.

It is clear from the description of this embodiment that when the at least one outer impact member is not present, a similar embodiment wherein the at least one inner impact member is formed as a single profile with a stepped inside is possible. It is also clear that a similar embodiment is possible wherein only the at least one outer impact member is formed as a single profile with a stepped inside. In these two last embodiments it is not required to foresee a recess for receiving the connection profile of the base member. It is also clear that these two last embodiments can be combined.