Note: Descriptions are shown in the official language in which they were submitted.
CA 02877495 2014-12-22
WO 2014/009021 Al
December 18, 2014
Gartner, Christian
G10347W0 RR/ba
Crosswind Deflection Element for Preventing Sedimentation
The invention relates to a crosswind deflection element with the features of
the
preamble of claim 1, which is intended for being set up in the open country,
in
particular at critical places exposed to strong winds, such as crests or the
like. The
occurrence of strong crosswinds at such places in the country often results in
a deposit
of solid material carried along by the air, such as wind-borne sand or snow.
In the
winter, at crests, for example, such snow deposits can become dangerous,
because they
may lead to the formation of snow avalanches if the deposits are not
systematically
removed, e.g. by repeated blasting operations. However, routine blasting
operations
carried out in order to remove dangerous snow overhangs in the mountains are
costly
and time-consuming and not always sufficient in order to effectively prevent
the
formation of avalanches.
In the prior art, so-called snow fences have among others been used to
influence the
undesired accumulation of snow caused by the wind. The fences set up at
critical places
in the country systematically cause an accumulation of snow in order to
prevent snow or
wind-borne sand, for example, from being blown onto a street or the like.
However,
such fences are not appropriate to effectively prevent an accumulation of
solid material
present in the air and carried along by strong crosswinds, a so-called
sedimentation,
under all circumstances. The other conventional avalanche protection elements
proposed in the prior art, which are intended for being set up at critical
places in the
mountains, either involve the deviation or the breaking of snow or debris
avalanches
that have been set off. That means, they are not appropriate for
systematically
preventing the formation of such debris or snow avalanches.
Starting from this prior art, it is the object of the present invention to
provide a
crosswind deflection element for an assembly in the open country, by means of
which a
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deposit of solid material from the air can systematically be prevented.
Furthermore, the
crosswind deflection element according to the invention should be as easy to
manufacture and assemble in the country as possible.
This problem is solved by means of a crosswind deflection element with the
features of
claim I. Advantageous embodiments and further developments of the invention
are
subject matter of the dependent claims.
The crosswind deflection element according to the invention, which is provided
for
being set up in the open country in order to systematically prevent a deposit
of snow,
wind-borne sand or the like, comprises a baseplate at the bottom for anchoring
into the
ground, a central post rising up from the baseplate, as well as a plurality of
guide plates
mounted on the post for deflecting the wind, and is characterized in that the
guide plates
are provided projecting in vertical orientation in a cruciform manner on the
post, and
that the length of the guide plates increases from the baseplate upwards.
Thus, the guide
plates of the crosswind deflection elements, which systematically catch and
deflect the
wind, are provided such that they protrude in vertical orientation from the
post so that
they provide a contact surface for occurring crosswinds, which is as large as
possible.
The length of the guide plates is shorter in the lower region and increases
from the
lower region upwards, so that a trapezoid shape is formed, the width of which
is larger
at the upper end than at the lower end of the crosswind deflection element.
All guide
plates are mounted on a central post rising up from the baseplate such that
the
crosswind deflection element can be mounted in a self-supporting and
freestanding
manner without the need of additional stay ropes or the like. For mounting and
setting
up the crosswind deflection element according to the invention, a baseplate is
provided
at the bottom, on which the central post is firmly mounted. The baseplate
serves for
setting up and anchoring the element in the ground at places in the country
where it is
desired to systematically prevent a deposit of solid material carried along by
the air.
Due to the fact that the guide plates become longer towards the upper side,
the surface
of the crosswind deflection element, which opposes the striking wind,
increases towards
the upper side. As a result of this inventive measure, the crosswinds are
caught in a
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systematic and enhanced manner and are in a kind of nozzle effect guided
downwards
by forming intensified swirls. These intensified swirls in the area of the
crosswind
deflection element effectively prevent the deposit of solid material from the
air, such as
sand or snow. When the crosswind deflection element according to the invention
is set
up at critical places in the mountains, such as at crests or hilltops, the
formation of
avalanches due to undesired local deposits can be prevented with comparatively
simple
means, as the solid material carried along by the wind does not accumulate at
places
where the crosswind deflection elements are set up, but are swept away by the
systematically deflected wind. The crosswind deflection element according to
the
invention thus prevents with a construction comparatively simple in design the
formation of undesired deposits (sedimentation) in the open country, no matter
whether
these deposits are deposits of wind-borne sand or snow deposits. The crosswind
deflection element according to the invention can preferably be set up in
groups of
several crosswind deflection elements of this kind at respective places in the
country,
which are problematic in view of strong winds. Due to the central post, each
of the
elements as such is extremely robust and can be set up in a freestanding
manner.
Consequently, the installation and the assembly of the crosswind deflection
elements
are comparatively simple, as only the central post requires a preinstalled
foundation or a
counter plate in the ground.
According to an advantageous embodiment of the invention, the guide plates for
the
deflection of the crosswinds are arranged at predetermined distances to each
other at the
post such that a row of permeable clearances is formed between the guide
plates. The
wind guide elements of the crosswind deflection element, which are formed by
the
guide plates, are thus provided over a comparatively large area, but provide a
certain
kind of permeability due to the clearances. On the one hand, this is
advantageous in that
the elements do not form a solid barrier over the whole surface and are
interrupted by
clearances, which allow a person to see through the elements. The intervention
into
nature is thus comparatively small. On the other hand, due to the clearances
between the
guide plates, the elements are less susceptible to damage as a result of very
strong
winds, which often occur particularly in the mountains. Consequently, a long-
term
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assembly and stability of the elements is guaranteed. According to an
advantageous
aspect in this regard, the width of the clearances can in particular be half
the width of
the guide plates such that still a sufficiently large deflection area for
striking winds is
guaranteed, which leads to the formation of swirls on the ground due to the
nozzle
effect and guarantees a secure prevention of a local sedimentation.
According to another advantageous embodiment of the invention, the guide
plates are at
least at their free ends coupled to each other such that they form four sail-
like wind
guide elements, which protrude in a cruciform manner from the post. Thus, the
guide
plates, which consist of single elements, are securely connected and coupled
with each
other such that they form in spite of their permeability a common and stable
component
for the purpose of a systematic deflection of winds. The single guide plates
may, for
example, be coupled by means of a rigid connection, such as a welding with
rods or
profiled elements. Alternatively, the coupling may be carried out by means of
flexible
elements, such as wire ropes or the like. The guide plates, which are coupled
with each
other, respectively protrude in a cruciform manner from the central post and
form some
kind of a trapezoid sail having a larger width at the upper end of the element
than on the
bottom side.
According to another advantageous embodiment of the invention, upper and lower
cross
members, which protrude from the post in a cruciform manner, are provided for
retaining and additionally securing the guide plates. When such upper and
lower cross
members, which protrude from the post in a cruciform manner, are given, the
laterally
protruding guide plates can be mounted in a safe and fixed manner, without the
weight
of the whole element being strongly increased. For the guide plates may be
provided in
the form of very thin sheet metal, for example, which itself does not have a
high
inherent stability, but which has in connection with the cross members, which
may, for
example, be provided in the form of profiled tubes, the necessary rigidity in
view of
impinging winds, even in the case of strong winds. The mounting and the
assembly of
the guide plates between the cross members can be carried out in different
ways: by a
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fixed welding to longitudinal bars, by inserting the guide plates into
recesses, by a
mounting by means of ropes stretching between the cross members, or the like.
According to another advantageous embodiment of the invention, the baseplate,
on
which the post is mounted so as to rise vertically upwards, is realized in a
two-piece
form and is provided with an installation aid, preferably a plug-in system of
the type
pipe-in-pipe. The baseplate can, for example, consist of a first member plate
and a
second bottom plate, the member plate being firmly connected to the post and
the
bottom plate being provided for being installed in the ground. The bottom
plate can be
made of a metal material and/or a combination of a metal and a concrete
material such
that a secure foundation for the crosswind deflection element to be set up is
provided.
According to the invention, an installation aid, e.g. in the form of a plug-in
system of
the type pipe-in-pipe, is provided for the mounting: to this end, the bottom
plate
comprises, for example, a pipe of a smaller diameter, onto which the pipe of a
somewhat larger diameter of the post of the crosswind deflection element can
simply be
slipped on from above. Thus, already upon the first installation of the
crosswind
deflection element, the position is securely fixed, and for the assembly the
two plate
elements of the baseplate must only be screwed together, for example. This
enhances in
particular a mounting in rough terrain through the air by means of a
helicopter. Only
one single worker is required on the ground. Furthermore, the necessary
intervention
into nature is minimal.
According to a further advantageous embodiment of the invention, the guide
plates or
the four wind guide elements formed of the guide plates are respectively
additionally
secured to upper and/or lower strut members at upper and/or lower ends of the
post. The
strut members can, for example, be realized by ropes or rods extending
diagonally from
a free end or a center portion of the guide plates or the cross members to the
central
post. By means of such strut members, the stability and the resistance to
striking winds
is further increased. Thus, without a strong increase in the weight of the
element, a very
robust construction for the purpose of a deflection of winds can be obtained.
For
example, the strut members can be made up of stretched wire ropes, which are
attached
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to connecting flanges. However, in the present case, the strut members may
also be
realized in a fixed manner, e.g. by means of welded rods. It is a further
advantage of the
compact and comparatively simple construction of the crosswind deflection
element
that the crosswind deflection element may be mounted in the country in a free-
standing
manner, i.e. no disturbing lateral anchorage by means of wire ropes or the
like is
required, which would require several anchorage points and concrete
foundations or the
like, respectively.
According to a further advantageous embodiment of the invention, the guide
plates,
which catch and deflect the wind, consist of sheets of a metal material, which
are in the
longitudinal direction profiled or corrugated. In this manner, the guide
plates may be
manufactured from a comparatively thin sheet material and are thus very
lightweight.
All in all, this leads to a lightweight structure of the entire crosswind
deflection element,
which is an advantage, in particular when it needs to be transported by a
helicopter in
order to be set up in rough terrain. Furthermore, the guide plates with
profiles or
reinforcing ribs in the longitudinal direction are sufficiently stable so that
a deformation
due to strong winds can be prevented.
According to a further advantageous embodiment of the invention, the guide
plates are
rigidly mounted in a respective circumferential frame, which itself is
attached to the
post. The four guide plates protruding laterally in a cruciform manner given
by way of
example are thus fixedly assembled within a frame, respectively, and form a
compact
unit. The frame may consist of welded profiled tubes and increases the
stability and the
rigidity of the element. The guide plates themselves are securely fixed in
their
respective frames at the desired position. The mounting of the frame itself on
the central
post can be realized in a detachable manner by means of screw connections with
respective flanges or the like, for example.
According to a respective alternative embodiment of the invention, the
respective guide
plates of a group of guide plates, which form a common wind guide element, are
connected to each other and secured in their position by means of coupling
ropes
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between upper and lower cross members. For example, a first coupling rope may
be
stretched between an upper and a lower cross member at the free end of the
guide
plates, and in the center portion there may be one coupling rope or several
coupling
ropes, which respectively hold the guide plates in the four directions and in
the desired
vertical orientation.
According to a further advantageous embodiment of the invention, an anti-
rotation
device is provided for an installation of the element, which is secure against
rotation.
An anti-rotation device may, for example, be realized by means of a pin or a
stud at the
bottom plate, which engages into a respective borehole. Other anti-rotation
devices are
also possible. The anti-rotation device is advantageous in that the crosswind
deflection
element cannot rotate in view of its position depending on the impact of the
crosswinds,
so that a strong swirl of the crosswinds and a systematic deflection towards
the bottom
side is guaranteed at all times.
According to a further advantageous embodiment of the invention, means for
avoiding a
rotation of the element during the transport through the air by means of a
helicopter or
the like are provided. The crosswind deflection element can thus simply be
lifted with a
hook of a helicopter and securely be transported through the air to the
installation site.
Also in case the element is lifted with a crane, the rotation of the element
is prevented.
Means for preventing the rotation of the element during the transport through
the air
may, for example, be realized in the form of a protruding rod with a wind cone
at its
free end. The rod protrudes laterally from the crosswind deflection element
and
comprises at its end the wind cone so that the element remains in its
respective position
and cannot rotate in the air. Other means for preventing the rotation of the
element
during a transport through the air may also be provided.
According to a further advantageous embodiment of the invention, the length of
the
guide plates increases from the bottom upwards up to approximately the double.
That
means, the length of the lowermost guide plate is approximately half the
length of the
uppermost guide plate. The surface for the systematic deflection of the
impinging winds
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thus increases relatively strongly from the bottom upwards, the crosswind
deflection
element according to the invention thus leading to an improved deflection,
deviation
and creation of swirls due to the above-mentioned nozzle effect. As a result,
an even
better prevention of deposits of solid material in the area and the vicinity
of the
crosswind deflection elements is guaranteed.
Further advantages, features and objects of the present invention will become
apparent
from the following description of embodiments. In the following, the invention
will be
described in more detail on the basis of embodiments and with reference to the
attached
drawings. In the drawings:
Fig. 1 is a perspective view of a crosswind deflection element of
the invention
according to a first embodiment of the invention;
Figs. 2a, 2b are a side view and a plan view from above of the crosswind
deflection
element according to the first embodiment of Fig. 1;
Fig. 3 is a side view of an inventive crosswind deflection element
according to
a second embodiment; and
Fig. 4 is a side view of an inventive crosswind deflection element
according to
the second embodiment at the moment of the installation of the element.
A first embodiment of a crosswind deflection element 10 according to the
invention as
shown in different views in Figs. 1, 2a and 2b will be explained in the
following. The
crosswind deflection element 10 is intended for an installation in the open
country, a
baseplate 1 at the bottom being provided at the lower end of the element 10 to
this end.
The baseplate 1 is here shown with four threaded pins, which are screwed into
respective holes with an internal screw thread and are screwed down for a
fixation at a
foundation (not shown) at the installation site or a counterplate. The
crosswind
deflection element 10 consists substantially of a central post 2, on which
guide plates 3
protruding laterally and in a cruciform manner are mounted, which serve for a
systematic deflection and for the formation of swirls of winds impinging on
the element
10. In this embodiment, the guide plates 3 are provided such that they
protrude in a
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cruciform manner in four directions from the central post 2, while being
mounted
between upper cross members 4 and lower cross members 5. The length of the
guide
plates 3 is shorter in the lower area and increases continuously towards the
upper side.
Thus, the guide plates 3 form together four trapezoidal wind guide elements
30,
respectively, as can in particular be taken from the side view of Fig. 2a.
These wind
guide elements 30 are intended for systematically catching, swirling and
deflecting the
impinging crosswind downwards into the area surrounding the crosswind
deflection
element 10 so that a deposit of solid material from the air, such as wind-
borne sand or
snow, can be prevented systematically. To this end, the length of the guide
plates 3 of
the wind guide elements 30 increases towards the upper side, thus creating
some kind of
nozzle effect in view of impinging winds, which swirls and routes the wind
together
with the solid material contained in the air towards the bottom without
leading to an
increased deposit around the crosswind deflection element 10. Thus, when a
plurality of
such crosswind deflection elements 10 is installed in the country at places
susceptible to
deposits (at crests or at mountain overhangs, for example), the generation of
snow
deposits, for example, can be prevented systematically. As a result, the
formation of
snow avalanches can effectively be prevented, as they are securely prevented
with the
invention even prior to the formation of undesired snow accumulations due to
wind-
and terrain-related conditions. Another field of application of such crosswind
deflection
elements is the prevention of sedimentation, i.e. a deposit of wind-borne sand
in desert
regions or coastal areas, for example. Also in this case, the crosswind
deflection
element serves for a systematic and effective prevention of deposits around
the element
10 by catching and deflecting the crosswind by means of the four wind guide
elements
protruding in a cruciform manner from the post 2, which are made up of a
plurality
25 of single guide plates 3. Other than in the case of conventional fences
or barriers, no
snow or sand deposits are formed on the lee side.
In the first embodiment shown in Figs. 1, 2a and 2b, the guide plates 3 are
mounted
between upper and lower cross members 4, 5 in the form of square profiles by
means of
30 coupling ropes 9. The coupling ropes 9 are fixed at mounting flanges on
the profiled
tubes of the cross members 4, 5 and hold the respective guide plates 3 in
their desired
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position and place. The guide plates 3, which can, for example, be made of a
thin sheet
metal, are respectively mounted at a distance to each other such that
clearances of
approximately half the width of the guide plates 3 are formed. Thus, the
crosswind
deflection element 10 is not completely solid, but is provided with
clearances, which
allow a person to see through the elements. Furthermore, the clearances
between the
guide plates 3 are advantageous in that in case of very strong winds the
elements 10 do
not run the risk of being swept away or being damaged by the wind. In the
first
embodiment, the central post 2 protrudes somewhat over the upper cross members
4,
which form the upper end of the wind guide elements 30. At the upper and lower
cross
members 4, 5, respective strut members 6, 7 are provided between the lower and
the
upper end of the post and approximately in the center of the cross members 4,
5. The
strut members 6, 7, which can, for example, be realized in the form of
tensible wire
ropes or iron rods, increase the stability of the crosswind deflection element
10 without
excessively increasing the overall weight. The strut members 6, 7 also serve
for taking
up the tensile stress applied by means of the coupling ropes 9, so that the
wind guide
elements 30 in the form of a kind of a sail can be stretched, the width
increasing
towards the upper side. In this embodiment, the four cross members 4, 5
protruding in a
cruciform manner from the post 2 are also respectively mounted by means of
mounting
flanges and respective screw connections. However, the cross members can
alternatively also be fixedly connected with the post 2, by means of a welding
of metal
pipes, for example. The detachable mounting by means of mounting flanges and
screw
connections is however advantageous in that the transport of the crosswind
deflection
elements 10 is facilitated and that less volume is necessary to this end. The
crosswind
deflection element 10 according to the invention is provided with
comparatively large
surfaces for deflecting and systematically routing the impinging winds. The
guide plates
3 protruding in a cruciform manner into four directions guarantee a deposit of
solid
material from the air also in the case of changing wind directions. The wind
can hit the
crosswind deflection element 10 from all directions, without deposits of snow
or sand,
for example, being formed on the back side (lee side), as is the case with
conventional
fences or the like, which are in the winter set up at the roadside of rural
roads, for
example, in order to prevent snowdrifts.
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Figure 3 shows in a side view a second embodiment of the crosswind deflection
element
according to the invention. Contrary to the first embodiment described above,
the
guide plates 3 are here mounted by means of a circumferential frame 8, the
frame 8 of
5 the four wind guide elements 30 protruding in a cruciform manner being in
this case
mounted altogether on the central post 2 by means of respective mounting
flanges and
screw connections. The guide plates 3 are, for example, welded into the frame
8. Also
here, respective upper and lower cross members 4, 5 are provided, which form
together
with a somewhat thinner rod or profile the frames 8 at the ends of the guide
plates 3.
10 This form of the wind guide elements 30 is advantageous in that the
single guide plates
3 are securely held together and fixed in their positions. Figure 3 shows on
the left-hand
side and on the right-hand side, respectively, an alternative of this
embodiment. While
on the left-hand side of Fig. 3 a strut member 6 is only provided at the upper
cross
member 4 between the free end of the cross member 4 and the upper end of the
post 2
and no lower strut member is provided, in the right-hand-side example
an upper strut member 6 and a lower strut member 7 are ¨ as in the first
embodiment ¨
provided, which are fixed between the post 2 and approximately the center of
the
respective cross members 4, 5 and provide for additional stability.
Alternatively, the
strut members can be omitted ¨ both in this embodiment and in the first
embodiment.
Also in this embodiment (Fig. 3), the guide plates 3 of the crosswind
deflection element
10 are made of a comparatively thin sheet material. The sheet material can be
provided
with profiles or reinforcement ribs running in the longitudinal direction, so
that the
guide plates 3 are in spite of the comparatively thin material sufficiently
stable to
withstand varyingly strong wind conditions and provide the desired effect by
swirling
and deviating the wind downwards in order to prevent sedimentation. Also in
this case,
the other members of the crosswind deflection element 10 can preferably be
made of a
metal material. In the embodiments shown, the central post 2 is realized as a
round pipe.
Alternatively, it may, however, also be realized as a rectangular pipe, as are
the upper
and lower cross members 4, 5 in these embodiments. Also here, the lower end of
the
post 2 is provided with a baseplate 1, which is reinforced by means of
triangular
reinforcement struts. The baseplate 1 has holes for a mounting via screw
connections.
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The mounting situation of the crosswind deflection element 10 according to an
embodiment of the invention on site is shown in a schematic side view of Fig.
4.
Figure 4 shows a situation in which the crosswind deflection element 10 is
carried
through the air by means of a helicopter or a crane (not shown) shortly before
it is put
down at the desired position in the terrain. To this end, the upper end of the
element 10
is fixed at a helicopter cargo hook 14. During the transport, the crosswind
deflection
element 10 is provided with a means 11 for preventing a rotation of the
element 10 in
the air, which is here shown in the form of a wind cone or a wind sleeve 11,
which is
mounted by means of a rod protruding laterally from the lower cross member 5.
By
providing such an anti-rotation means 11, the crosswind deflection element 10
is
securely carried through the air and put down at the desired site in the
terrain by a
simple descent of the helicopter. For this purpose, a foundation plate 16 made
of
concrete was installed on the ground, on which a bottom plate 13 is mounted,
onto
which the member plate 12 of the baseplate 1 is placed. In order to facilitate
the release
and the installation of the crosswind deflection element 10, the bottom plate
13 is
provided with a centrally arranged pipe socket 15, the diameter of which is
somewhat
smaller than the inner diameter of the central post 2. Thus, the two plates
12, 13 of the
baseplate 1 can be placed on top of each other in the form of a plug-in system
of the
type pipe-in-pipe, so that the crosswind deflection element is directly upon
release in
the right position and secured from the beginning. Then, only a screw
connection or
another connection of the two plates 12, 13 of the baseplate 1 is required in
order to
guarantee a secure fixation of the free-standing crosswind deflection element
10. In this
manner, no lateral anchoring means, such as anchor ropes, are required, as
they are
required with conventional snow fences or the like in order to guarantee an
upright
position also in the case of strong winds. The anti-rotation means 11 in the
form of a
wind cone guarantees that the element 10 is always aligned with the wind
during
transport, as illustrated by arrow W in Fig. 4. After the release and the
fixation of the
crosswind deflection element 10, the wind cone 11 is removed along with its
fixation
rod and can be reused for a further transport of another crosswind deflection
element 10
of the same kind, which is to be set up.
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The invention provides an effective crosswind deflection element 10, which,
over a
large area, securely avoids a deposit of solid material from the air on this
place as a
result of the creation of swirls and the systematic redirection of the wind.
The crosswind
deflection element 10 according to the invention is, due to its construction
with a
plurality of comparatively thin guide plates 3, which protrude in a cruciform
manner
from a central post 2, very light in weight so that a transport via helicopter
is rendered
possible. The total weight of the crosswind deflection element 10 is
preferably less than
550 kg. Furthermore, the crosswind deflection element 10 according to the
invention
requires only a comparatively small-scale intervention in natural
environments, because
the elements must only be set up at certain places in groups, respectively,
and no large-
scale building operations for the prevention of snow avalanches, debris
avalanches or
deposits of wind-borne sand are necessary. The invention is not limited to the
embodiments illustrated above and can be modified in various ways. In
particular, the
form of the guide plates may vary. In the embodiments illustrated above, the
length of
the lowermost guide plate 3 is approximately half the length of the uppermost
guide
plate 3, so that a comparatively strong enlargement of the wind guide elements
30
towards the upper side is given. Alternatively, the enlargement towards the
upper side
can also be less or more.
The guide plates 3 can be made of flat or profiled sheet metal, i.e. of
relatively thin
sheet metal, with reinforcing deformations in the longitudinal direction.
However, the
guide plates 3 may also be provided with reinforcing ribs, so that the high
stability is
guaranteed despite the lightweight construction. Also, the guide plates 3 may
be fixed at
the central post 2 by other means than by coupling ropes 9 or a
circumferential frame 8
as shown in the illustrated embodiments. For example, the guide plates 3 may
be
mounted by means of retainer slots provided in the post 2 and by a fixed
welding. Also,
the distance of the guide plates 3 towards each other may be varied, e.g. to
deliberately
cause a higher permeability in certain areas: for example, the upper guide
plates 3 may
be mounted at larger distances to each other than the lower guide plates 3
close to the
ground, taking into account the stronger winds in the upper area.
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