[0001] The present invention relates to an obstacle deflector for a rail vehicle.
[0002] An obstacle deflector for a rail vehicle, also known as snowplough or pilot, is a
device which is usually placed at the front end of a carbodyshell of a rail vehicle,
such as a train, and is arranged to deflect possible obstacles present on the railway
track that might otherwise derail the train when the latter is travelling along the
track. Obstacles should be deflected as early as possible because otherwise they might
damage the train, thus resulting in unnecessary maintenance costs.
[0003] Figure 1 shows a schematic lateral view of a train 1 having an obstacle deflector
2 which is fixed to the front end of its carbodyshell 4 and is capable of performing
the primary task of removing obstacles from the railway track, thus protecting the
train 1 from derailment. However, this obstacle deflector 2 is not capable of protecting
the carbodyshell 4 from damages, because it happens quite frequently that obstacles
firstly hit the cover panel of the carbodyshell 4 and only later they are pushed away
by the obstacle deflector 2.
[0004] In fact, an obstacle deflector designed according to the EN 15227 standard has usually
to be installed in longitudinal direction behind or in a back position below the energy
absorber elements, also known as energy dissipation devices, which are fixed, in known
manner, to the front end of the carbodyshell 4 and are arranged to absorb the impact
energy in case of impacts with obstacles which may be present on the path of the train
1.
[0005] In order to guarantee the proper functioning of these energy absorber elements, the
obstacle deflector 2 is usually placed behind them because otherwise, due to the fact
that it is a fixed element, in case of crash events it would restrain the energy absorber
elements, not allowing their proper functioning.
[0006] As a result, the front end of the carbodyshell of the train 1, with its grp (glass
reinforced plastic) structure and equipment, remains unprotected.
[0007] It is therefore an object of the present invention to provide an obstacle deflector
for a rail vehicle which is capable of both removing obstacles from the railway track
and protecting the carbodyshell of the train from impacts with these obstacles, thus
overcoming the limitations of the prior art solutions.
[0008] This and other objects are fully achieved by virtue of an obstacle deflector for
a rail vehicle having the characteristics defined in independent claim 1.
[0009] Preferred embodiments of the invention are specified in the dependent claims, whose
subject-matter is to be understood as forming an integral part of the present description.
[0010] Further characteristics and advantages of the present invention will become apparent
from the following description, provided merely by way of a non-limiting example,
with reference to the enclosed drawings, in which:
- Figure 1 shows a schematic lateral view of a train having an obstacle deflector according
to the prior art;
- Figure 2 shows a schematic lateral view of a train having an obstacle deflector according
to the present invention;
- Figure 3 shows a lateral view of the train of figure 2 with its obstacle deflector;
- Figure 4 shows a perspective view of an obstacle deflector according to the present
invention;
- Figure 5 shows a perspective view of the obstacle deflector of figure 4 in an extended
position, when seen in a direction different from the one of figure 4;
- Figure 6 shows a perspective view of the obstacle deflector of figure 5 in a retracted
position, when seen in the same direction as in figure 4;
- Figure 7 shows a perspective view of an alternative embodiment of the obstacle deflector
according to the present invention;
- Figure 8 shows a perspective view of the obstacle deflector of figure 7 in an extended
position, when seen in a direction different from the one of figure 7; and
- Figure 9 shows a perspective view of the obstacle deflector of figure 8 in a retracted
position, when seen in the same direction as in figure 7.
[0011] Briefly, the obstacle deflector of the present invention is capable of both removing
obstacles present on a railway track and protecting the carbodyshell of a train without
requiring modifications to the energy absorber elements usually present on the front
end of a carbodyshell of a train.
[0012] The obstacle deflector of the present invention, thanks to the fact that of being
movable, can be placed in front of the energy absorbers because during a crash scenario
it is arranged to slide back without affecting the operation of the energy absorbers.
[0013] The obstacle deflector according to the present invention has the same functionalities
as any other fixed mounted deflector of the prior art according to the EN 15227 standard.
[0014] Figure 2 shows a schematic lateral view of a train 10 having an obstacle deflector
12 fixed to the front end of its carbodyshell 14 in a forward position with respect
to the prior art, so that obstacles first collide with the obstacle deflector 12 and
then are moved away from the railway track.
[0015] The obstacle deflector 12 is mounted in an extended position so as to project forward
beyond energy absorber elements of the train 10: when an obstacle approaches the train
10, it firstly impacts the obstacle deflector 12.
[0016] If the level of the impact force between the obstacle and the obstacle deflector
12 itself is below a predetermined threshold, the obstacle deflector 12 pushes the
obstacle away from the railway track, otherwise, it moves to a retracted position
wherein it does no more project beyond the energy absorber elements.
[0017] Figure 3 shows a lateral view of the train 10 with its obstacle deflector 12 placed
under energy absorber elements 22, and another opposed train 10' with its obstacle
deflector 12' placed under its energy absorber elements 22'.
[0018] In case of crash between the two trains 10 and 10', the respective obstacle deflectors
12 and 12' move from the extended position shown in figure 3, wherein they project
beyond the corresponding energy absorber elements 22 an 22', to the retracted position,
wherein they do not project beyond the corresponding energy absorber elements 22 an
22', as disclosed herein below in detail.
[0019] In order to withstand accidents with obstacles having an impact force level below
a threshold, for example equal to 300kN, as indicated in the scenarios disclosed in
the EN 15227 standard, the obstacle deflector 12 is positioned, as above indicated,
so as to project beyond the energy absorber elements 22, while having at the same
time the stability and stiffness required by EN 15227 standard. The obstacle deflector
12 is however able to move backwards to the retracted position if the impact force
level exceeds said threshold.
[0020] With reference to figure 4 the obstacle deflector 12 of the present invention includes
a support member 18 having a buckling-free system, for example a sledge 16 (e.g. a
Coradia LINT, a light regional train of Alstom TD), and a shield element 20 fixed
to a front end 16a of the sledge 16. The sledge 16 is carried by the support member
18 so as to be slideably movable with respect to the support member 18 between a first
position represented on figures 4 and 5, the above-cited extended position, and a
second position represented on figure 6, the above-cited retracted position. The sledge
16 and the shield 20 together form a sub-assembly 17, movable with respect to support
member 18.
[0021] The support member 18 is arranged to be fixed at a proximal end 18a to a front end
of the carbodyshell 14 of the train 10.
[0022] The sledge 16 is arranged to slide between the extended position, wherein the shield
element 20 is spaced from a distal end 18b of the support member 18 and is arranged
to push away obstacles placed in front of the train 10, and the retracted position,
wherein the shield element 20 is in contact with such distal end 18b of the support
member 18.
[0023] In case of a crash force exceeding the threshold, the sub-assembly 17, and thus the
sledge 16, can slide into the lower area of the grp part of the carbodyshell 14, thus
moving from the extended position to the retracted position.
[0024] In order to allow this sliding movement of the sub-assembly 17, the sledge 16 and
the support member 18 are connected by tearing elements 21, such as breakable screws,
one of which is represented in an exploded position on figure 5. This allows sledge
16 to slide with respect to support member 18, from the extended position of figures
4 and 5, to the retracted position of figure 6, when the tearing elements 21 are broken
due to an impact force of an obstacle on the shield element 20 exceeding the threshold
of the impact force.
[0025] Two energy absorber elements 22, placed side by side above the obstacle deflector
12, are arranged to be fixed at a proximal end 22a to the carbodyshell 14 of the train
10 without being in contact with the obstacle deflector 12, and the shield element
20 is mounted so that, in the extended position, it project forwards beyond distal
ends 22b of the energy absorber elements 22. In the retracted position, the shield
element 20 does not project anymore beyond the distal end 22b of the energy absorber
elements 22, so that it does not interfere with an obstacle if this obstacle interacts
with the energy absorber elements 22.
[0026] Energy absorber elements 22 are distributed on either sides of a central longitudinal
axis X14 of carbodyshell 14. For the sake of simplicity energy absorber elements 22
are not represented on figures 5 and 6.
[0027] Figure 5 is a further perspective view of the obstacle deflector 12 of figure 4 with
its sub-assembly 17 in the extended position; while figure 6 is a perspective view
of the obstacle deflector 12 of figure 4 with its sub-assembly 17 in the retracted
position.
[0028] Figure 7 is a perspective view of an alternative embodiment of the obstacle deflector
12 of the present invention which includes two lateral rods 24 and a supporting member
or box 26 arranged to host said rods 24. Two energy absorber elements 22 are distributed
on either sides of a central longitudinal axis X14 or carbodyshell 14. For the sake
of simplicity energy absorber elements 22 are not represented on figures 8 and 9.
[0029] The shield element 20 and the rods 24 together form a sub-assembly 17, movable with
respect to support member 18. Preferably, tearing elements 21 are screws or bolts.
[0030] The shield element 20 is fixed to a front end 24a of the rods 24.
[0031] The rods 24 are arranged to slide between the extended position, wherein the shield
element 20 is spaced from a distal end 26b of the supporting member 26 and is arranged
to push away obstacles placed in front of the train 10, and the retracted position,
wherein the shield element 20 is in contact with such distal end 26b of the supporting
member 26.
[0032] Figure 8 is a further perspective view of the obstacle deflector 12 of figure 7 with
its sub-assembly 17 in the extended position, while figure 9 is a perspective view
of the obstacle deflector 12 of figure 7 with its sub-assembly 17 in the retracted
position.
[0033] Advantageously, in one embodiment and/or the other, the obstacle deflector 12 comprises
also an anticlimber known per se, in order to avoid to slide vertically when compressed
to the retracted position and to remain in a horizontal position.
[0034] In all embodiments, when the impact force level exceeds the above cited threshold,
the tearing elements 21 break and the sub-assembly 17 moves from the extended position
to the retracted position.
[0035] The tearing elements 21 such as the above cited bolts or screws are common elements
which shall break in a controlled manner. In particular, the tearing elements 21 have
to break at the predefined impact force level threshold.
[0036] Preferably, the threshold of the impact force is higher than the level of forces
occurring during one impact against a big obstacle, and therefore higher than the
requirements provided by the fourth scenario of the EN15227 standard.
[0037] The obstacle deflector 12 can remain in its retracted position without losing its
functionality while, in an alternative embodiment, it is locked in the retracted position
so as not to slide, but after a crash this should not be a real problem anymore.
[0038] Clearly, the principle of the invention remaining the same, the embodiments and the
details of production can be varied considerably from what has been described and
illustrated purely by way of non-limiting example, without departing from the scope
of protection of the present invention as defined by the attached claims.
1. Obstacle deflector (12) for a rail vehicle (10) having a carbodyshell (14) with a
front end, the obstacle deflector (12) comprising:
- a support member (18, 26) arranged to be fixed at a proximate end (18a) to the a
front end of the carbodyshell (14);
- a moving element (16, 24) supported by said support member (18, 26) so as to be
slideably movable with respect to the support member (18, 26);
- a shield element (20) fixed to a front end (16a, 24a) the moving element (16, 24);
wherein the moving element (16, 24) is arranged to move between:
- an extended position, wherein the shield element (20) is spaced from a distal end
(18b, 26b) of the support member (18, 26) and is arranged to push away an obstacle
placed in front of the rail vehicle (10); and
- a retracted position, wherein the shield element (20) is in contact with the distal
end (18b, 26b) of the support member (18) and is arranged not to push away said obstacle.
2. The obstacle deflector (12) of claim 1, wherein:
in the extended position, the shield element (20) is arranged to project forward beyond
a distal end (22b) of energy absorber elements (22) fixed to the front end of the
carbodyshell (14); and
in the retracted position, the shield element (20) is arranged not to project beyond
the distal end (22b) of the energy absorber elements (22).
3. The obstacle deflector (12) of claim 1 or 2, wherein the moving element (16, 24) is
arranged to move from the extended position to the retracted position when the force
of an impact between an obstacle and the shield element (20) exceeds a predetermined
threshold.
4. The obstacle deflector (12) of claim 2, wherein one of said energy absorber elements
(22) is placed on the moving element (16, 24) between two portions (19) of the support
member (18).
5. The obstacle deflector (12) of any of the preceding claims, wherein the moving element
is a sledge (16).
6. The obstacle deflector (12) of any of the preceding claims, wherein the moving element
is formed by two lateral rods (24).
7. The obstacle deflector (12) of claim 6, wherein the support member (26) is a supporting
box (26) arranged to host said lateral rods (24).
8. The obstacle deflector (12) of any of the preceding claims, wherein the moving element
(16, 24) and the shield element (20) together form a sub-assembly (17) movable with
respect to the support member (18, 26).