Note: Descriptions are shown in the official language in which they were submitted.
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Title: Scaffolding system, as well as a coupler of such system and a
method for the manufacture of the coupler
The invention relates to a scaffolding system, comprising scaffolding
tubes as well as at least one scaffolding coupler for detachably
connecting the scaffolding tubes to each other, wherein the scaffolding
coupler comprises two tube receiving parts.
A scaffolding coupler is known from, inter alia, Dutch patents NL75356,
NL7117188 and NL7811721, and is suitable in particular for easy
connection of scaffolding tubes, in particular standardized scaffolding
tubes according to the NEN-EN 39:2001 standard (such tubes have an
external diameter of 48.3 mm). With the known systems, tube clamping
is effected by striking home a wedge. In this manner, the scaffolding
coupler can be rapidly mounted and demounted. A drawback of the
known scaffolding coupler is that parts of the coupler consist of
relatively much material, so that the manufacture thereof involves
relatively high material costs.
The object of the invention is an improved scaffolding system. The object
of the invention is in particular a system which can be manufactured at
relatively low costs and contributes to durability. To this end, the
scaffolding system comprising scaffolding tubes and at least one
scaffolding coupler for detachably connecting the scaffolding tubes to
each other is characterized, according to the invention, in that one or
more parts of the scaffolding coupler substantially consist of oval-shaped
wire.
The scaffolding coupler mentioned comprises at least two tube receiving
parts, which are each preferably formed by, inter alia, two steel,
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substantially U-shaped profiles, in the state of the art technique formed
from round, solid wire. According to an elaboration of the invention, one
or more of the U-shaped profiles mentioned are formed by oval-shaped
wire (i.e., wire having an oval-shaped cross section). It may then be
elected to use oval-shaped drawn wire, or rolled wire, in particular
formed from basic wire having a circular cross section.
An advantage of the invention consists in a considerable reduction of the
material use compared to the conventional coupler, with preservation of
a desired strength of the coupler. In this manner, a considerable weight
reduction can be achieved. When the steel wire is to be galvanized, the
galvanizing costs can be reduced considerably due to a decrease in steel
surface to be galvanized. Further, the weight reduction is a major
advantage for transport and efficient end use of the couplers.
In a preferred embodiment, the U-shaped profiles define at least a part
of a tube clamping space for the scaffolding tubes, of which a tube insert
opening is closable by at least one closing element, which is hingeable
from a release position to a tube clamping position. The hinge axis
between a tube receiving part and a closing element may then be
provided with a wire having a circular cross section or, for instance,
likewise an oval-shaped cross section.
The closing element can be secured in the tube clamping position by, for
example, a wedge, detachably or non-detachably connected to the
scaffolding coupler. The wedge connected to the scaffolding coupler may
be fastened to the closing element in a non-detachable manner by means
of a connection consisting of oval-shaped wire, drawn or not drawn.
If required, the tube receiving parts may be rotatably connected,
resulting in a swivel coupler.
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Further, an aspect of the invention provides a coupler of a system
according to the invention. With it, the above mentioned advantages can
be achieved.
In clarification of the invention, various exemplary embodiments will be
described with reference to the drawings.
Fig. 1 is a side view of an exemplary embodiment of a scaffolding
system;
Fig. 2 is a perspective of a cross coupler;
Fig. 3 is a side view from the direction A of the coupler shown in Fig. 2;
Fig. 4 is a cross section along the line V-V of Fig. 3;
Fig. 5 is a perspective of a swivel coupler; and
Fig. 6 is a schematic top plan view of a swivel coupler as shown in Fig. 5.
Fig. 1 is a side view of an exemplary embodiment of a scaffolding system,
which includes, for example, horizontally extending scaffolding tubes a
and vertically extending scaffolding tubes b which are connected by
means of scaffolding couplers in the form of cross couplers c. In the
example, further, scaffolding tubes d are represented which are coupled
diagonally to the scaffolding system. Theses tubes d are connected to
other tubes (for example, vertical or horizontal tubes) by swivel
couplers e. It will be clear to those skilled in the art that such a system a,
b, c, d, e can be implemented in various ways. The tubes mentioned are in
particular scaffolding tubes that comply with the NEN-EN 39:2001
standard.
Figs. 2, 3 and 4 show a scaffolding coupler of the scaffolding system
represented in Fig. 1. The coupler serves for detachably connecting
scaffolding tubes which are oriented at right angles to each other (also
called a cross coupler).
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In this example, the scaffolding coupler is formed by a first tube
receiving part la and a second tube receiving part lb. Each tube
receiving part la is built up from steel, substantially U-shaped profiles
2a, 2b. In this example, a steel substantially U-shaped profile consists of
five sections, viz., a base, two (oppositely extending) side legs which are
preferably at right angles to the base, and two end parts/ends which are
bent over, at right angles to the side legs or not so. The side legs and
base part mentioned can for instance be substantially straight profile
sections, but this is not requisite. Use of slightly bent sections is an
option too. Further, a substantially U-shaped profile as mentioned can
for instance comprise fewer than the five sections mentioned, for
instance when one or two end parts as mentioned are absent.
According to a preferred embodiment, each substantially U-shaped
profile consists of oval-shaped wire, in particular steel wire. The term
'oval-shaped wire' may be understood to mean a wire element having a
substantially oval cross section (see Fig. 4), where for instance a
thickness D1 measured in a first direction (along a first main axis, the
long axis, of the oval) deviates considerably from a thickness D2 in a
second direction (for instance along a second main axis, the short axis, of
the oval), normal to the first direction. The oval mentioned can be, for
example, an ellipse, with two axes of symmetry Xl, X2 (as in Fig. 4)
extending normal to each other.
In the example, it holds for the thicknesses mentioned that D1>D2. A
thickness ratio D1:D2 may for example be in the range of 4-1.5, in
particular 3-1.5, or another range. According to a preferred embodiment,
D1:D2 is in the range of 13:8-15:8; the ratio D1:D2 can be, e.g., 14:8.
According to a preferred embodiment, the thickness in the first direction
D1 is greater than 13 mm, for example a thickness of 14 mm or 15 mm.
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According to a preferred embodiment, the thickness in the second
direction D2 is less than 11 mm and greater than 5 mm, for example, a
thickness D2 of 8 mm or 7 mm.
According to an especially advantageous embodiment, the thickness in
5 the first direction D1 is 14 mm and the thickness in the second direction
D2 is 8 mm.
It has been found that through the use of the above-mentioned thickness
ratios (D1:D2) and wires thicknesses (D1, D2), a particularly powerful
scaffolding tube coupler configuration can be obtained, with relatively
little material consumption. A mass saving of over 10% can thus be
obtained with respect to the traditional scaffolding tube coupler.
Additionally, in this manner, a considerable reduction of an outer
surface of the coupler can be achieved, which provides advantages in a
surface treatment (e.g., galvanizing).
An especially durable configuration is achieved when neighboring
sections of a substantially U-shaped profile are mutually bent over in a
bending plane which is parallel to a long main axis X1 of the oval (see
Figs. 3, 4). The substantially U-shaped profile can for instance be formed
by bending wire having an oval-shaped cross section as mentioned, with
bending axes being parallel to the short axis X2 of the oval.
In an alternative, the neighboring sections of a substantially U-shaped
profile are, conversely, mutually bent over in a bending plane which is
parallel to a short main axis X2 of the oval. In that case, bending over
can be carried out using relatively little force with respect to bending in
the earlier- mentioned direction, i.e., in the plane parallel to the long
main axis X1.
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According to a further elaboration, the first tube receiving part la and
the second tube receiving part lb are bonded together by means of a
welded connection, whereby the inner side of the bases of two steel,
substantially U-shaped profiles 2a, 2b of a tube receiving part la are
welded to the inner side of the bases of the two steel, substantially
U-shaped profiles 2c, 2d of the other tube receiving part lb. Here, the
tube insert openings of the first tube receiving part la and the second
tube receiving part lb face away from each other.
According to a further elaboration (see Figs. 3, 4), the connection is such
that ¨ viewed in cross section ¨ long main axes X1 of the two base
sections (bases) of the one tube receiving part la touch long main axes of
the bases of the other tube receiving part lb. In particular, the
connection is such that ¨ viewed in cross section ¨ short main axes X2 of
the bases of the one tube receiving part la run substantially parallel to
the short main axes X2 of the bases of the other tube receiving part 1b,
and at a distance from each other. In this manner, an especially durable
connection can be achieved, in particular when welding the bases
together.
In particular (see Figs. 3, 4), the bases of the first tube receiving part la
and the bases of the second tube receiving part (in particular
through/during welding) are to some extent sunk into each other/fused
together, via mutually facing end faces.
The two steel, substantially U-shaped profiles 2a, 2b of a receiving part
la define a part of the tube clamping space, which is closable with a
hingeable closing element 3a. The closing element 3a is hingeable from a
release position to the tube clamping position about a hinge axis 6a. The
hinge axis 6a is for instance non-detachably connected to the tube
receiving part la, more specifically at right angles to the bent-over parts
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of the steel substantially U-shaped profiles 2a, 2b, and consists of oval-
shaped wire.
The closing element 3a is fixable in the tube clamping position with a
wedge 4a, which is non-detachably connected to the closing element 3a
by means of a connection 5a of oval-shaped wire.
It may be elected to make use of drawn oval-shaped wire for the
elements consisting of oval-shaped wire. A method for drawing wire is
further elucidated hereinafter.
Figs. 5 and 6 show an alternative embodiment, viz., a scaffolding coupler
for detachably connecting, for example, horizontally or vertically
oriented scaffolding tubes to scaffolding tubes that are diagonally
oriented. Tubes B being engaged are drawn-in in Fig. 6. In this example,
the scaffolding coupler is formed by a first tube receiving part la and a
second tube receiving part lb. Again, each tube receiving part la is built
up from steel, substantially U-shaped profiles 2a, 2b. In this example, a
steel, substantially U-shaped profile consists of five parts: a base, two
side legs which are preferably at right angles to the base, and two ends
which are bent over, preferably at right angles to the side legs. In this
example also, the profile preferably consists of oval-shaped wire, which
is bent into the substantially U-shaped form. The first tube receiving
part la and the second tube receiving part lb are connected to each
other by a rotatable connection R (for instance, comprising two revolving
discs rotatably coupled to each other), with the openings of the tube
receiving parts la, lb facing away from each other. A rotational axis of
the rotatable connection extends in particular at right angles to the
bases of the substantially U-shaped profiles, which will be clear to those
skilled in the art. In particular, the bases of the tube receiving parts are
fixedly welded to revolving plates/flanges of the rotatable connection.
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Here, the tube insert openings of the first tube receiving part la and the
second tube receiving part lb face away from each other. The two steel,
substantially U-shaped profiles 2a, 2b of a receiving part la define a
part of the tube clamping space, which is closable by a hingeable closing
element 3a. The closing element 3a is hingeable from a release position
to the tube clamping position about a hinge axis 6a. The hinge axis 6a is
for instance non-detachably connected to the tube receiving part la,
more specifically at right angles to the bent-over parts of the steel,
substantially U-shaped profiles 2a, 2b. The hinge axis 6a consists, for
example, of wire having a substantially circular cross section.
A method for forming the wire mentioned can utilize, for example, wire
rolling or wire drawing, whereby a steel base wire (for instance, having
a circular cross section) is deformed. The oval-shaped wire can for
instance be formed by deformation of steel wire of initially circular cross
section, having, for example, a thickness (outer diameter) in the range of
12-15 mm, in particular an outer diameter of 14 mm.
Wire of this kind has been found to be suitably workable, in particular
bendable, to form the substantially U-shaped profiles therefrom. The
scaffolding coupler formed with these substantially U-shaped profiles is
strong and durable, and thus safe and reliable in use.
It will be clear to those skilled in the art that the invention is not limited
to the exemplary embodiments described. Various modifications are
possible within the framework of the invention as set forth in the
following claims.
For instance, the steel wire is preferably galvanized for the purpose of
reducing or preventing corrosion. Galvanizing is preferably carried out
after formation of the oval cross section.
