Note: Descriptions are shown in the official language in which they were submitted.
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Back railing
The present invention relates to a back railing consisting of a tube and two
hooks
with one of the hooks being attached to each end region of said tube.
Back railings are important parts of scaffolds for improving the safety of the
personnel
working on these scaffolds. In the past these back railings of modular
scaffolds
consisted, for example, of a tube having a feeding head attached to each of
its ends
by a wedge. Said wedge was anchored to the perforated disk of the vertical
scaffolding tube by the use of a hammer. Said back railing has the
disadvantage that
the feeding head can only be manufactured at great expense and is adding to
the
weight of the back railing. In addition to this, tools are needed for the
assembly/disassembly of these back railings.
It is therefore an object of the present invention to provide a back railing
not showing
the disadvantages of the prior art and facilitating an easier assembly.
According to the present invention, said object is achieved by providing a
back railing
consisting of a tube and two hooks with one of the hooks being attached to
each end
region of said tube.
The tube may be any tube of any cross-section and any diameter. Preferably the
tube
has a spherical cross-section with a diameter between 35 mm and 45 mm.
The tube has two hooks attached to it. One of the hooks is attached to each
end
region of said tube in an arbitrary manner. They can be, for example, screwed,
riveted or welded to the tube.
Preferably the hooks are manufactured from any rod-shaped material having an
arbitrary cross-section. Particularly preferred the hooks are manufactured
from
cylinder-shaped material preferably having a diameter of 10-14 mm. Preferably
the
hooks are manufactured by bending. The hooks may be made from plastic or metal
with metal being preferred.
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Preferably the hooks are attached to the tube in such a way that the central
axis of
the hooks forms an angle of 45°-135°, preferably of 75°-
115° and more preferably
preferred of 85°-95°, relative to the vertical central axis of
the tube.
In a preferred embodiment of the present invention the hooks have one straight
segment and at least one angular segment, said straight segment having a
length of
30-80 mm and said angular segment having a length of 20-60 mm. The angular
segment forms an angle of 15°-165°, preferably 45°-
135° and more preferably of 85°-
95°, relative to the straight segment of the hook.
In a preferred embodiment of the present invention the hook consists of so
many
short angular segments that the shape of said hook either approximates a
circular-
bent hook or that the hook is circular-bent.
Also preferred the back railing according to the present invention
additionally has
suspension sheets to which the hooks are attached. Said suspension sheets are
preferably attached to the ends of the tube and are preferably angular-shaped.
In another preferred embodiment of the back railing according to the present
invention the ends of the tube are flattened and the hooks are attached to
said
flattened segments of the tube.
The back railing of the present invention is attached to any scaffold with a
matching
receiving device, preferably perforated disks with openings, by positioning
the lower
tip of each hook above one of said openings of one receiving device and by
rotating
the whole back railing of the present invention around its longitudinal axis
and
thereby fitting the hooks into the openings and attaching the back railing to
the
perforated disks in such a way that it cannot come undone. Therefore the
process of
attaching the back railings of the present invention to a scaffold, preferably
a modular
scaffold, is also claimed.
This way the back railing can be attached to any perforated disk known to
someone
skilled in the art, as disclosed, for example, in US 5 605 204, particularly
in figure 2,
2
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DE-PS-24 49 124, particularly in figures 1 a and 1 b; DE-OS-196 02 737,
particularly in
figure 1, EP-PS-0 289 825, particularly in figure 3 and in the german
application 198
44 612.8 of the applicant, particularly in figures 1 and 2. Said documents are
hereby
incorporated by reference and become part of the disclosure.
The back railing of the present invention has the advantage that is much
easier
manufactured than back railings known from the prior art. The back railing of
the
present invention can easily be assembled by one grasp and without the use of
any
tools. The back railing of the present invention can be attached to any
scaffold having
perforated disks. The back railing of the present invention has a lower weight
than
back railings with a feeding head.
With references to the figures 1-4 the present invention will be illustrated
below. The
illustrations are only meant to explain the present invention, not to limit
its scope.
In the drawings:
Figure 1 shows the back railing of the present invention having a hook
attached to its
flattened ends.
Figure 2 shows the back railing of the present invention with the hook being
attached
to a suspension sheet.
Figure 3a and 3b each show an example of the hook.
Figure 4 shows the back railing in its built-in state.
Figure1 illustrates one end of the back railing according to the present
invention. The
other end of the back railing is identical to this. The tube 2 of the back
railing has a
diameter of 38 mm and a wall thickness of 1,8 mm and is flattened at its ends.
The
hook 3 is pressed into said end 9. The hook 3 has a straight segment 12 and an
angular segment 4. The hook 3 is attached to the tube 2 in such a way that the
central axis 13 of the hook 3 forms an angle of 90°, relative to the
vertical central axis
of the tube 2.
3
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The back railing of the present invention is attached to the small openings 6
of the
perforated disk 7 of the vertical scaffolding tube 10 in such a way that it
cannot come
undone. It is obvious to someone skilled in the art that the back railing of
the present
invention can be attached to the openings of any perforated disk. It is also
clear to
someone skilled in the art that the back railing of the present invention can
also be
attached to the big openings 11 of the perforated disk, if the tube 2 is of
the
respective length.
Figure 2 illustrates one end of the back railing according to the present
invention.
The other end of the back railing is identical to this. The tube 2 of the back
railing has
a diameter of 38 mm and a wall thickness of 1,8 mm. A suspension sheet 8 is
welded
to the end of the tube 2. The suspension sheet serves as a bearing surface for
the
back railing of the present invention. The hook 3 is pressed into said
suspension
sheet 8. The hook 3 has a straight segment 12 and an angular segment 4. The
hook
3 is attached to the suspension sheet 8 in such a way that the central axis 13
of the
hook 3 forms an angle of 90°, relative to the vertical central axis 5
of the tube 2.
The back railing of the present invention is attached to the small openings 6
of the
perforated disk 7 of the vertical scaffolding tube 10 in such way that it
cannot come
undone. It is obvious to someone skilled in the art that the back railing of
the present
invention can be attached to the opening of any perforated disk. It is also
clear to
someone skilled in the art that the back railing of the present invention can
also be
attached to the big openings 11 of the perforated disk, if the tube 2 is of
the
respective length.
Figure 3a illustrates an example of the hook according to the present
invention. The
hook 3 has a straight segment 12 and an angular segment 4, both segments
forming
an angle of 90°, relative to each other. The hook is bent out of
cylindrical-shaped,
solid material having a diameter of 12 mm. The straight segment has a length a
of 60
mm and the angular segment has a length b of 30 mm. It is known to someone
skilled in the art that the hook can also be made from tube-shaped material
and that
the two segments can also be welded to each other.
4
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Figure 3b illustrates an example of the hook according to the present
invention. The
hook 3 has a straight segment 12 and an angular segment 4, both segments
forming
an angle of 90°, relative to each other. An additional segment 14 is
connected to the
angular segment 4. The straight segment has a length a of 51 mm, the angular
segment has a length b of 45 mm and the additional angular segment has a
length c
of 5 mm. The hook is bent out of cylindrical-shaped, solid material having a
diameter
of 12 mm. It is known to someone skilled in the art that the hook can also be
made
from tube-shaped material and that the two segments can also be welded to each
other.
Figure 4 illustrates the back railing of the present invention in its built-in
state. The
length of the tube 2 is dimensioned in such a way that the back railing can be
suspended between two vertical scaffolding tubes 10 of a modular scaffold.
Suspension sheets 8 are welded to each end of the tube 2 and the hooks 3 are
attached to said suspension sheets 8.
The back railing 1 is attached to the openings 6 of the perforated disks 7
between
two vertical scaffolding tubes 10 in such a way that it cannot come undone.
