U.S. patent application number 15/043232 was filed with the patent office on 2017-08-17 for impact attenuator and vehicle, trailer and guardrail comprising such an impact attenuator.
The applicant listed for this patent is Verdegro Holding B.V.. Invention is credited to Sjoerd Degroot, Gerrit Verwijs.
Application Number | 20170234393 15/043232 |
Document ID | / |
Family ID | 58159501 |
Filed Date | 2017-08-17 |
United States Patent
Application |
20170234393 |
Kind Code |
A1 |
Degroot; Sjoerd ; et
al. |
August 17, 2017 |
IMPACT ATTENUATOR AND VEHICLE, TRAILER AND GUARDRAIL COMPRISING
SUCH AN IMPACT ATTENUATOR
Abstract
An impact attenuator including an impact head, coupled to a
first end of an energy absorption body, which energy absorption
body is arranged for fixation to an external structure at a second
end opposing the first end of the energy absorption body,
configured to at least partly absorb or dissipate energy from a
collision of an object with the impact head, and including a first
part and a second part extending substantially lengthwise behind
each other, wherein the first and second part are mutually moveable
and including a first and a second cutting edge, wherein, the first
cutting edge is arranged for splitting the first part of the energy
absorption body upon impact of an object colliding with the impact
head, and the second cutting edge is arranged for consecutively
splitting the second part of the energy absorption body upon impact
of an object colliding with the impact head.
Inventors: |
Degroot; Sjoerd;
(Roosendaal, NL) ; Verwijs; Gerrit; (Roosendaal,
NL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Verdegro Holding B.V. |
Etten-Leur |
|
NL |
|
|
Family ID: |
58159501 |
Appl. No.: |
15/043232 |
Filed: |
February 12, 2016 |
Current U.S.
Class: |
256/13.1 |
Current CPC
Class: |
E01F 15/148 20130101;
B62D 21/152 20130101; B62D 63/062 20130101; E01F 15/143 20130101;
E01F 15/04 20130101; F16F 2230/0023 20130101; E01F 15/146 20130101;
F16F 7/123 20130101 |
International
Class: |
F16F 7/12 20060101
F16F007/12; E01F 15/14 20060101 E01F015/14; E01F 15/04 20060101
E01F015/04; B62D 21/15 20060101 B62D021/15; B62D 63/06 20060101
B62D063/06 |
Claims
1. An impact attenuator comprising: an impact head, coupled to a
first end of an energy absorption body, which energy absorption
body is arranged for fixation to an external structure at a second
end opposing the first end of the energy absorption body,
configured to at least partly absorb or dissipate energy from a
collision of an object with the impact head, and comprising a first
part and a second part extending substantially lengthwise behind
each other, wherein the first and second part are mutually
moveable; a first and a second cutting edge, wherein the first
cutting edge is arranged for splitting the first part of the energy
absorption body upon impact of an object colliding with the impact
head, wherein the first cutting edge is moveable between an engaged
position where the first cutting edge is positioned for splitting
the first part of the energy absorption body upon mutual movement
the first part and the second part of the energy absorption body,
and a retracted position where the first cutting edge is positioned
away from the first part of the energy absorption body to allow
free mutual movement the first part and the second part of the
energy absorption body; and the second cutting edge is arranged for
consecutively splitting the second part of the energy absorption
body upon impact of an object colliding with the impact head.
2. The impact attenuator according to claim 1, wherein the first
part and the second part of the energy absorption body are mutually
moveable in their lengthwise direction.
3. The impact attenuator according to claim 1, wherein the first
part and the second part of the energy absorption body are
configured for guiding each other during mutual movement of said
first part and the second part of the energy absorption body.
4. The impact attenuator according to claim 3, wherein the energy
absorption body comprises rollers provided between the first part
and the second part of the energy absorption body.
5. (canceled)
6. The impact attenuator according to claim 1, wherein the first
cutting edge and the second cutting edge are provided at an end of
the second part of the energy absorption body facing towards the
impact head.
7. The impact attenuator according to claim 1, wherein the first
part and the second part of the energy absorption body each
comprise a thin-walled beam, which thin-walled beams comprise at
least a web and a flange plate.
8. The impact attenuator according to claim 7, wherein the first
part of the energy absorption body comprises a H-beam and the
second part of the energy absorption body comprises a hollow
structural section.
9. The impact attenuator according to claim 7, wherein the first
and second cutting edges are, by means of relative position to the
thin-walled beam of the first part and the second part of the
energy absorption body, configured for splitting the thin-walled
beams along an interface of a web and flange plate.
10. The impact attenuator according to claim 9, wherein the impact
attenuator is provided with at least one deflection surface,
configured for deflecting split off beam plates away from a
colliding object.
11. The impact attenuator according to claim 1, wherein one of the
first part and second part of the energy absorption body is nested
within the other one of the first part or second part of the energy
absorption body.
12. The impact attenuator according to claim 1, wherein the energy
absorption body comprises an adjustable coupling configured for
coupling the impact attenuator to an external structure, wherein
the adjustable coupling allows adjustment of the angle enclosed
between the energy absorption body and the external structure.
13. A vehicle provided on a rear side thereof with an impact
attenuator according to claim 1, which impact attenuator is
configured to move between: an essentially horizontal position,
wherein the impact attenuator extends substantially parallel to a
road surface, and an essentially vertical position, wherein the
impact attenuator is folded behind the vehicle.
14. A trailer comprising the impact attenuator of claim 1, wherein
the impact attenuator is disposed on at least one axle provided
with a set of wheels.
15. A guardrail, provided on a front end thereof with the impact
attenuator of claim 1.
Description
TECHNICAL FIELD
[0001] The following specification relates to an impact attenuator
for roadside application, suited for reducing the severity of a
collision by absorbing at least part of the kinetic energy of an
object, and specifically a vehicle, colliding with said impact
attenuator. The specification furthermore relates to a vehicle
comprising such an impact attenuator, a trailer comprising such an
impact attenuator and a guardrail comprising such an impact
attenuator.
SUMMARY
[0002] Roadside impact attenuators are intended to reduce the
damage to vehicles, structures and motorists in the event of a
(motor) vehicle collision by absorbing the colliding vehicle's
kinetic energy. Common impact attenuators hereby deform, or more
specifically split material as a method to dissipate kinetic
energy. To split the material, a cutting surface is installed and
configured to cut into the attenuator structure upon impact of a
colliding vehicle. In common cases, the cutting surface hereby
progressively splits a steel box beam in its lengthwise direction
from the moment of impact up till the standstill of the vehicle.
For safety reasons, it is desirable to increase the length over
which the attenuator structure is split, as to lengthen the
deceleration time for the vehicle as much as possible to minimize
the deceleration (G-forces) experienced by the passengers. This
means that, from a safety perspective, the attenuator structure
must as long as practically possible. However, the total length of
the impact attenuator is limited due to transportation
requirements. Especially attenuators suited for temporary use in
road construction projects or truck mounted attenuators are
frequently transported and need to conform to the height, width and
length requirements set for road transport.
[0003] An object of the specification is therefore to provide an
impact attenuator that offers improved safety, better
transportability and/or at least provides a useful alternative to
the state of the art.
SUMMARY
[0004] The specification hereto proposes an impact attenuator
comprising: an impact head, coupled to; a first end of an energy
absorption body, which energy absorption body is arranged for
fixation to an external structure at a second end opposing the
first end of the energy absorption body, configured to at least
partly absorb or dissipate energy from a collision of an object
with the impact head, and comprising a first part and a second part
extending substantially lengthwise behind each other, wherein the
first and second part are mutually moveable; a first and a second
cutting edge, wherein upon impact of an object colliding with the
impact head, the first cutting edge is arranged for splitting the
first part of the energy absorption body, and the second cutting
edge is arranged for consecutively splitting the second part of the
energy absorption body.
[0005] The impact attenuator according to the specification thus
comprises an energy absorption body that extends between the impact
head and an external structure, which energy absorption body is
specifically configured for being cut into and consequently split
by the cutting edges. Upon collision of an object with the impact
head, the energy absorption body absorbs at least part of the
kinetic energy of the colliding object. Consecutively, the absorbed
energy is (at least partly) dissipated by the splitting action of
the cutting edges, which plastically deforms the energy absorption
body and causes friction that generates thermal energy (heat).
[0006] By dividing the energy absorption body into multiple parts
that are moveable with respect to each other, it becomes possible
to extend the energy absorption body to its fullest length by
letting the individual parts of the energy absorption body extend
substantially behind each other in a lengthwise direction. This
creates a maximum distance between the impact head and the external
structure with which the impact attenuator is coupled, improving
the attenuator's inherent safety. Namely, the increase in the
distance over which the object is decelerated allows for more time
for a colliding object to come to rest or change its direction and
therefore, which leads to a more gradual deceleration of the
colliding object. At the same time, the multiple parts of the
energy absorption body can be moved to a different mutual
orientation in which the maximum length of the impact attenuator is
reduced to allow for convenient transportation. It is for example
possible to remove, fold or retract the individual parts such that
the total of parts constituting the impact attenuator adhere to
certain predetermined maximum dimensions.
[0007] To ensure the continuous and subsequent splitting of the
energy absorption body over its (entire) length, the impact
attenuator comprises multiple (at least two) cutting edges, which
cutting edges may be part of one or more cutting means. The cutting
edges are positioned such that the multiple parts of the energy
absorption body are separately and subsequently split by separate
cutting edges that are part of either the same or separate cutting
means. This creates essentially self-contained parts of the energy
absorption body that work independently, making the assembly of
said parts fail-safe to at least a certain degree. Moreover, the
interface between the separate parts of the energy absorption body,
which may create a discontinuity in the construction of the energy
absorption body, does not hinder a continuous splitting action, due
to the separate and consecutive splitting of the individual parts
of the energy absorption body.
[0008] It is also possible that the energy absorption body
comprises more than two parts, to further reduce the minimum
dimensions of the impact attenuator when transported or to further
increase the maximum distance between the impact head and the
external structure to improve the impact attenuator's collision
safety.
[0009] In a further embodiment the first part and the second part
of the energy absorption body are mutually moveable in their
lengthwise direction. The direction of mutual movement of the
absorption body parts hereby corresponds to the anticipated
direction of impact, which ensures that the impact attenuator will
behave as predicted in the case of a collision. In addition,
relative movement of the energy absorption parts in any other
direction may be prevented for similar reasons.
[0010] In yet a further embodiment, the first part and the second
part of the energy absorption body may be configured for guiding
each other during mutual movement of said first part and the second
part of the energy absorption body. As the first part and the
second part of the energy absorption body act as each other's
guiding structure, mutual movement of these parts will take place
along a predetermined path in lengthwise direction of the energy
absorption body. The relative motion of the individual parts of the
energy absorption body is hereby limited to essentially a single
degree of freedom (i.e. a translation along a straight path), which
makes that the deformation behaviour of the attenuator in the event
of a collision becomes more predictable and therefore more safe.
Moreover, the guided movement of the energy absorption body parts
benefit the easy conversion of the attenuator from an operational
to a transport configuration.
[0011] Additionally, the energy absorption body may comprise
rollers provided between the first part and the second part of the
energy absorption body. These rollers reduce friction and
facilitate the mutual movement of said first part and the second
part of the energy absorption body. Alternatively, a similar
reduction in friction could be obtained by the application of
materials with a low coefficient of friction along the interface of
the first part and the second part of the energy absorption
body.
[0012] In order to retract the energy absorption body in an
efficient way the first cutting edge may be moveable between: an
engaged position, wherein the first cutting edge is positioned for
splitting the first part of the energy absorption body upon mutual
movement the first part and the second part of the energy
absorption body, and a retracted position, wherein the first
cutting edge is positioned away from the first part of the energy
absorption body to allow free mutual movement the first part and
the second part of the energy absorption body. The free mutual
movement the first part and the second part of the energy
absorption body allow for an easy retraction of the impact
attenuator in its lengthwise direction, which benefits the
transportability of the impact attenuator. Adjustment means may be
applied to move the cutting edge (and the associated cutting means)
between the engaged and retracted position. Such movement may
comprise a rotation or a translation along a path that in part lies
within the movement path of the first part of the energy absorption
body and in part lies outside the movement path of the first part
of the energy absorption body.
[0013] The first cutting edge and the second cutting edge may be
provided at an end of the second part of the energy absorption body
facing towards the impact head. By placing the cutting mechanisms
at an end of the second part of the energy absorption body, the
cutting mechanisms can commence cutting into the absorption body at
the respective ends of the first and second parts of the energy
absorption body, in the case that the separate parts of the energy
absorption body are fully extended behind each other. This enables
the cutting edges to split the energy absorption body over its
entire length, making full use of the body's arresting
capacities.
[0014] It is possible that the first part and the second part of
the energy absorption body each comprise a thin-walled beam, which
thin-walled beams comprise at least a web and a flange plate. A
thin-walled beam can be understood as a beam for which the wall
thickness is significantly smaller than the other representative
dimensions of the beam's cross-section. The use of one or more
thin-walled beams allows the energy absorption body to obtain a
high bending stiffness per unit cross sectional area, which is much
higher than that for solid cross sections, thereby achieving a
stiff beam at a minimum weight. To obtain a stable construction for
the energy absorption body, multiple parallel beams may be provided
between the impact head and the external structure to form (part
of) the first part and/or the second part of the energy absorption
body.
[0015] In an embodiment of the impact attenuator, the at least one
first part of the energy absorption body comprises a H-beam and the
at least one second part of the energy absorption body comprises a
hollow structural section. The H-beam and hollow structural section
type beams give the energy absorption body a high level of strength
and stiffness while intact, but can easily be split to obtain a
number of elongated, flat plates that can be easily bended.
[0016] Given that the energy absorption body may comprise
thin-walled beams, the first and second cutting edges may, by means
of relative position to the thin-walled beam of the first part and
the second part of the energy absorption body, be configured for
splitting the thin-walled beams along an interface of a web and
flange plate. Splitting the at least one beam along the interface
of web and flange plates yield essentially elongated, flat plates
that have little remaining stiffness and can therefore be easily
bended.
[0017] Bendability of the split off parts of the energy absorption
body is required for bending the parts, resulting from the
splitting operation, in a direction away from the colliding object,
the external structure and/or other objects that could otherwise be
damaged by these split off parts.
[0018] In order to achieve bending of the split off parts of the
energy absorption body, at least one first part of the energy
absorption body may be provided with at least one deflection
surface, which at least one deflection surface is configured for
deflecting split off beam plates away from the colliding object.
Moreover, the deformation (bending) of the split off beam plates by
the deflection surface dissipates, in addition to the splitting,
part of the colliding object's kinetic energy.
[0019] In an alternative embodiment, one of the first part and
second part of the energy absorption body is nested within the
other one of the first part or second part of the energy absorption
body. This means that the first part of the energy absorption body
may be nested within the second part of the energy absorption body
to obtain a telescoping construction, internally comprising the
first part of the energy absorption structure, and externally
comprising the second part of the energy absorption structure.
Alternatively, the second part of the energy absorption body may be
nested within the first part of the energy absorption body. The
telescoping construction allows the energy absorption body to
occupy the least amount of space when in a retracted position.
[0020] In yet another embodiment, the energy absorption body may
comprise an adjustable coupling configured for coupling the impact
attenuator to an external structure, wherein the adjustable
coupling allows adjustment of the angle enclosed between the energy
absorption body and the external structure. With the possibility to
adjust the angle enclosed between the energy absorption body and
the external structure, it becomes possible to set the orientation
of the impact attenuator such that it extends parallel to the road
surface.
[0021] The specification also relates to a vehicle provided on a
rear side thereof with an impact attenuator according to the
present specification, which impact attenuator is configured to
move between: an essentially horizontal position, wherein the
impact attenuator extends substantially parallel to a road surface,
and an essentially vertical position, wherein the impact attenuator
is folded behind the vehicle. In a common instance, said vehicle is
a road construction or maintenance truck that is especially prone
to collide with passing traffic. By mounting and deploying the
impact attenuator at the rear side of the vehicle, an impact
barrier is created between said vehicle and traffic approaching
from the rear. In addition, the impact attenuator could also be
deployed at the front side of a vehicle, to create an impact
barrier in case of a frontal collision. To minimize the length of
the vehicle when the impact attenuator is not in use as a roadside
barrier, the impact attenuator can be folded behind the vehicle in
a essentially vertical position. A hydraulic system may for example
be used for rotating or otherwise moving the attenuator to and from
a folding position.
[0022] In addition, the specification relates to a trailer
comprising an impact attenuator according to the present
specification, wherein the impact attenuator is disposed on at
least one axle provided with a set of wheels. The impact attenuator
itself may act as a chassis onto which one or more axles are
installed. An advantage of using such trailer as a temporary
roadside barrier, is that the impact attenuator may be used behind
a variety of vehicles. Additionally, the trailer may be used as a
stand-alone roadside barrier, wherein the trailer is not coupled to
any vehicle. In the case of stand-alone use, the trailer may be
equipped with additional weights to act as a ballast.
[0023] Last, the specification relates to a guardrail, provided on
a front end thereof with an impact attenuator according to the
present specification. Such guardrail equipped with an impact
attenuator is specifically suited for use at a head piece of a
guardrail, for example between a highway and an exit lane, along
the most probable line of impact. Hereby, the guardrail itself will
only act as an external structure with which the impact attenuator
is coupled. The impact attenuator may be (more so than the standard
guardrail) optimized for different impact scenarios to guarantee an
optimal safety for passing traffic. Moreover, the impact attenuator
offers an additional line of protection against accidental fails of
the guardrail.
BRIEF DESCRIPTION
[0024] The specification will now be elucidated into more detail
with reference to non-limitative exemplary embodiments shown in the
following figures. Corresponding elements are indicated with
corresponding numbers in the figures.
[0025] FIG. 1 shows a three-dimensional view of a preferred
embodiment of an impact attenuator according to the specification
in an extended position;
[0026] FIG. 2 shows a three-dimensional view of an impact
attenuator according to FIG. 1 in a retracted position;
[0027] FIG. 3 shows a side elevation of a trailer-implemented
impact attenuator according to the specification in a retracted
position;
[0028] FIG. 4 shows a side elevation of a trailer-implemented
impact attenuator according to FIG. 3 in an extended position;
[0029] FIG. 5 shows a three-dimensional view of a part of the
impact attenuator according to the specification;
[0030] FIG. 6 shows a three-dimensional view of another part of the
impact attenuator according to the specification;
[0031] FIG. 7 shows a three-dimensional view of a yet another part
of the impact attenuator according to the specification;
[0032] FIG. 8 shows an adjustable coupling for use in an impact
attenuator according to the specification;
[0033] FIG. 9a shows a three-dimensional view of an impact
attenuator according to the specification upon impact with a
vehicle;
[0034] FIG. 9b shows a three-dimensional view of an impact
attenuator according to the specification upon impact with a
vehicle;
[0035] FIG. 9c shows a three-dimensional view of an impact
attenuator according to the specification upon impact with a
vehicle;
[0036] FIG. 9d shows a three-dimensional view of an impact
attenuator according to the specification upon impact with a
vehicle;
[0037] FIG. 9e shows a three-dimensional view of an impact
attenuator according to the specification upon impact with a
vehicle; and
[0038] FIG. 10 shows a three-dimensional view of a guardrail
comprising an impact attenuator according to the specification.
DETAILED DESCRIPTION
[0039] FIG. 1 shows a three-dimensional view of a preferred
embodiment of an impact attenuator 1 according to the
specification. The impact attenuator 1 is shown in an extended
position, which corresponds to the attenuator's operational
configuration. The impact attenuator 1 comprises an energy
absorption body 2, on a first end provided with an impact head 3
and on a second end opposing the first end coupled to an external
structure by means of an adjustable coupling 4. Although the
adjustable coupling 4 as shown here allows specifically for
coupling the impact attenuator 1 to trucks or other vehicles, the
impact attenuator 1 could also be coupled to or be part of other
external structures, not exclusively including trailers (see for
example FIG. 2), guardrails (see for example FIG. 10) and ground
anchors. The energy absorption body 2 comprises a first part 5 and
a second part 6, extending past each other in a lengthwise
direction, wherein the first part comprises two H-beam structures 7
and the second part comprises hollow structural sections 8. The
H-beams 7 and hollow structural sections 8 can be provided with
through-holes 9 in order to reduce the weight of the structure.
Even though the energy absorption body 2 comprising two lengthwise
extending beams, which leads to a highly stable and stiff
structure, it is also possible that the energy absorption body 2
comprises a single beam structure comprising a single first and
second part. Alternatively, more than two lengthwise extending
beams can be used in the energy absorption body 2. The H-beam
sections are configured to slide over rollers 10 (visible in FIGS.
5-7), contained within the hollow structural sections 8, which
enables the H-beam sections 7 to move in lengthwise direction with
respect to the hollow structural sections 8, thereby performing a
telescoping movement. As an alternative to the rollers 10,
materials with a low coefficient of friction could be applied along
the interface of the H-beam sections 7 and the hollow structural
sections 8. First cutting means 11, comprising first cutting edges
12 (shown in FIGS. 6 and 7) and second cutting means 13, comprising
second cutting edges 14, are provided at an end of the second part
of the energy absorption body 2 opposing the end of the second part
connected to the adjustable coupling 4. The first cutting means 11
are hereby configured for splitting the first part 5 of the energy
absorption body 2, while the second cutting means 13 are configured
for splitting the second part 6 of the energy absorption body 2.
Alternatively, the second cutting means 13 could be mounted one a
side of the impact head 3 facing the external structure (truck) 4.
The impact head 3 is furthermore provided with deflection surfaces
15, which are configured for bending parts of the energy absorption
body 2 away from the colliding object after being split-up by the
second cutting means 13.
[0040] FIG. 2 shows a three-dimensional view of an impact
attenuator 1 according to FIG. 1, now depicted in a retracted
position, which corresponds to the attenuator's operational
configuration. Reference signs similar to those in FIG. 1 hereby
correspond to parts similar to those in FIG. 1.
[0041] FIG. 3 shows a side elevation of a trailer-implemented
impact attenuator 30 according to the specification. The impact
attenuator 30 is depicted in a fully retracted position, in which
it is most suited for transport. In this embodiment of the
specification, the impact attenuator 30 constitutes part of a
trailer 31. More specifically, the impact attenuator 30 constitutes
(part of) a chassis 32, that provides a mounting point for an axle
33 with a pair of wheels 34 suspended thereto. The trailer 31 can
be coupled to a vehicle by means of a common truck coupling 35.
[0042] FIG. 4 shows a side elevation of a trailer-implemented
impact attenuator 30 according to FIG. 3. The impact attenuator 30
is now depicted in a fully extended position, in which it is most
suited for use as a roadside barrier. Reference signs similar to
those in FIG. 3 hereby correspond to parts similar to those in FIG.
3.
[0043] FIG. 5 shows a three-dimensional view on a front end of a
second part 52 of an energy absorption body 51 of an impact
attenuator according to the specification. The front end of a
second part 52 of the energy absorption body 51 is provided with
second cutting means 53, comprising four second cutting edges 54,
for cutting hollow structural section 55 at its vertices, such that
essentially flat, bendable, elongated plates result from the
splitting action, which plates constitute the sides of the hollow
structural section 55. Deflection surfaces 56 are provided next to
the cutting edges 54, which are configured for bending the
elongated plates away from the colliding object. Rollers 57 are
shown, which rollers 57 are contained within the hollow structural
sections 55, for guiding a first part (not visible) of the energy
absorption body 51.
[0044] FIG. 6 shows a three-dimensional view of a part of the
impact attenuator according to the specification, which part
comprises a structure 58, contained within the hollow structural
section 55 as shown in FIG. 5, which structure 58 houses both the
first cutting means 59 and the second cutting means 53. Note that
reference signs similar to those in FIG. 5 correspond to parts
similar to those in FIG. 5. The structure 58 is configured for
guiding the first part 60 of the energy absorption body 51 by means
of rollers 57 part the first cutting means 59. The first cutting
means 59 comprise first cutting edges 61. In this figure, the first
cutting means 59 are depicted in a retracted position wherein the
cutting edges 61 keep clear of the H-beam 62 that is the first part
60 of the energy absorption body 51, allowing the H-beam 62 to
freely slide along the rollers 57. This allows the user to retract
the impact attenuator (for transport) such that the first part 60
of the energy absorption body 51 is substantially contained within
the second part of the energy absorption body 51. The structure 58
is on its corners provided with blocks 66 that form-fittingly
connect to the shape of the hollow structural section 55 and allow
the structure 58 to be guided along the hollow structural section
55, thereby cutting into the hollow structural section 55 by means
of the second cutting means 53. To ensure smooth movement of the
structure 58 relative to the hollow structural channel 55, either
the blocks 66 or the contact surface of the hollow structural
channel 55 with the blocks 66 could be at least in part be
manufactured from materials with a low coefficient of friction.
Alternatively, rollers could be provided between the structure 58
and the hollow structural channel 55. The structure is attached to
the hollow structural section 55 by means of shear bolts or pins
that are designed to break or shear in the case of a mechanical
overload caused by an impact of the impact head 63 with the
structure 58.
[0045] FIG. 7 shows a three-dimensional view of a part of the
impact attenuator according to the part shown in FIG. 6, wherein
similar reference signs correspond to similar parts. Again, a first
part 60 of the energy absorption body 51 is shown that is coupled
to an impact head 63 at a front end thereof. In this figure, the
first cutting means 59 are depicted in an engaged position, wherein
upon movement of the first part 60 of the energy absorption body
51, the cutting edges 61 cut into said first part 60 of the energy
absorption body 51, splitting the H-beam 62 alongside the interface
of the web plate 64 with the flange plates 65.
[0046] FIG. 8 shows an adjustable coupling 80 for use in an impact
attenuator according to the specification. The adjustable coupling
80 is configured for coupling the impact attenuator to an external
structure by means of a pair of brackets 82. The brackets 82 of the
coupling allow the impact attenuator to be hooked around a
protruding part of the external structure, which brackets 82
therefore provide for a fast and efficient connection of the impact
attenuator to said external structure. Moreover, the adjustable
coupling 80 allows adjustment of the angle enclosed between the
energy absorption body and the external structure by means of
jackscrews 81.
[0047] FIG. 9a-9e show a three-dimensional view of an impact
attenuator 90 according to the specification upon impact with a
vehicle 91. The figures show a sequence (a-e) of the impact of a
collision of the vehicle 91 on the impact attenuator 90. From the
sequence it becomes clear that the first part 93 of the energy
absorption body 92 is first split and then the second part 94. The
first part 93 is split into flat, bendable, elongated plates 98 by
means of first cutting means contained within the second part 94.
The second part 94 is consecutively split into flat, bendable,
elongated plates 95 that are bend away from the colliding vehicle
91 by deflection surfaces provided next to the second cutting means
97 and onto the impact head 96 as described above with reference to
FIG. 1 and FIG. 5. FIGS. 9d and 9e furthermore show that upon
splitting of the second part 94 of the energy absorption body 92,
the flat, bendable, elongated plates 98 that previously formed the
first part 93 of the energy absorption body 92 will protrude past
the rear end of the second part 94 of the energy absorption body
92. It is also conceivable that the impact attenuator 90 is, e.g.
by means of a different arrangement of the cutting edges,
configured for splitting the second part 94 of the energy
absorption body 92 before splitting the first part 93 of the energy
absorption body 92 upon impact of a vehicle 90 with the impact head
96.
[0048] FIG. 10 shows a three-dimensional view of a guardrail 100
comprising an impact attenuator 101 according to the specification.
The guardrail 100 hereby functions as an external structure with
which the impact attenuator 101 is coupled. Alternatively, the
impact attenuator 101 could be coupled to any other object posing
an imminent danger to passing traffic.
[0049] It will be apparent that the specification is not limited to
the exemplary embodiments shown and described here, but that within
the scope of the appended claims numerous variants are possible
which will be self-evident to the skilled person in this field. In
particular, bursting may be applicable instead of splitting, and H
or I beams may be tubes for instance. It is possible here to
envisage that different inventive concepts and/or technical
measures of the above described embodiment variants can be wholly
or partially combined without departing from the inventive concept
described in the appended claims.
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