EP1693531B1 - Truss - Google Patents

Abstract

The girder has an upper belt (21), and a lower belt arranged parallel to a upper belt in a transverse space. Distance rods are arranged parallel to each other in a longitudinal section. A diagonal rod consists of an oval-or ellipse shaped cross section at its end in a section transverse to its longitudinal section. Longitudinal axis of the cross section is attached parallel to a level stretched from the upper belt and the lower belt.

Description

The invention relates to a lattice girder, preferably of metal, in particular of aluminum or steel, for scaffolding, roof structures, bleachers, stairs, podiums and the like, with a top flange and a parallel thereto and arranged at a transverse distance lower flange, and with at least two mutually parallel and at a longitudinal distance arranged spacer struts, which are welded to the upper flange and the lower chord to a rigid frame and preferably formed perpendicular to the upper chord and the lower chord, and with at least one diagonal strut, preferably at least two diagonal struts disposed between the upper chord and the lower chord and welded at their ends to the upper and lower chords.

Such lattice girders, which are also referred to as parallel girders, have been known for many years. Applications in the field of scaffolds can be seen for example from DE 692 53 754 U, DE 27 37 859 A and DE 39 04 638 Al. Applications in roof structures or roofing go, for example, from DE-PS 2 031 168, DE 35 42 610 Al and DE 100 28 262 Al out. Go further Applications for podiums, for example, from DE 38 24 938 A1 and applications for grandstands from DE 39 19 156 A1.

Such lattice girders can be used, for example, as a stiffening frame, cheek parts, railings, roof trusses and in particular for safely bridging large spans.

Accordingly, the invention may also relate to a scaffold, a roof structure, a grandstand, a staircase or a podium and the like with a lattice girder with the aforementioned features.

There are different designs and attachments of such lattice girder possible. Thus, the parallel spacer or transverse struts and the parallel straps can be welded to a diamond-shaped or rectangular rigid frame. In the latter case, preferably the spacer struts are arranged perpendicular to the upper flange and the lower flange. Furthermore, lattice girders with more than two longitudinal belts arranged parallel to one another are possible, for example in the form of triangular lattice girders. The spacer struts are preferably arranged in the plane spanned by the upper and lower belt. Preferably, the ends of the upper and lower chords extend beyond the spacers. In particular, if the lattice girders have a greater length, one or more further spacer struts or cross connecting struts between the upper flange and the lower flange may be arranged between two outer spacer struts and welded thereto. These further spacer struts are preferably parallel to the aforementioned two spacer struts arranged. Furthermore, the further spacer or cross-connection struts can likewise be arranged in the plane spanned by the upper flange and the lower flange and preferably be welded at their two ends to the upper flange or the lower flange respectively.

The lower chord preferably runs along its entire length parallel to the upper chord. Furthermore, the lattice girder is preferably designed in each case with a straight continuous upper chord and a straight running lower chord.

The lattice girders may be fastened, for example by means of couplings, in particular double couplings, preferably on other struts or support elements and / or may preferably at the ends of the upper chord and / or the lower chord connecting elements such as hooks, claws, eyes, Lugs and connection shoes referred to as connection shoes, in particular those with horizontal slots for attachment to perforated discs and for attachment by means of a continuous wedge be designed. Finally, the upper straps may preferably be provided with tube connectors, push-in straps and other fastening auxiliary devices, for example for arranging and / or fastening further connecting or supporting elements.

The top flange and the bottom flange, the distance or cross struts and the diagonal struts have so far mainly consisted of round tubes, but they can also consist of square tubes. Furthermore, the top flange may be formed with special other profile designs, in particular as an upwardly open U-profile, or as T or I-profile, or in the form of a box profile with a rectangular cross-section.

Surprisingly, the lattice girders mentioned at the beginning, which have been used successfully for many years, can still be improved. For when welding the diagonal struts to the upper flange and to the lower flange, it may be in those areas in which the diagonal struts lie at an acute angle to the upper and lower flange and / or in which other diagonal struts and / or spacer struts are fastened closely adjacent, to problems, up to an inadequate connection in these areas.

It is therefore an object of the invention to provide a lattice girder in which the aforesaid problems can be avoided without sacrificing the bending and torsional rigidity of the lattice girder.

This object is achieved by the features of claim 1, in particular in that the diagonal strut at least at their ends, but preferably over its entire length or substantially over its entire length, in a section transverse to its longitudinal axis an oval or elliptical Has outer cross section, the longitudinal axis is arranged approximately parallel to the plane defined by the upper flange and the lower flange plane.

By these measures, the diagonal struts can be easily and safely welded to the upper and lower chords manually as well as mechanically, by being aware of the weld in the poorly accessible areas is omitted, so is placed only in the remaining abutment areas. In this way, so in a predefined area a weld can be easily and safely placed so that it comes to a consistently secure connection between the diagonal braces and the upper flange and the lower flange without sacrificing the bending and torsional stiffness of the lattice girder.

According to a preferred embodiment it can be provided that the diagonal strut is designed as a tube and preferably at least at its ends in a section transverse to its longitudinal axis has an oval or elliptical annular cross-section.

It is also advantageous if the oval or elliptical cross section is designed symmetrically to its longitudinal axis and / or transverse axis.

In a particularly advantageous design can be provided that the diagonal strut has at its outer periphery in its longitudinal direction extending edges. As a result, not only a higher rigidity of the entire lattice girder can be achieved, but these edges can be used as markers for the welding work such that the respective weld is placed up to a predetermined edge or up to several predetermined edges of the diagonal strut.

It is particularly advantageous if the diagonal strut has a preferably flat flattening on at least one of its sides assigned to its longitudinal axis. By means of this flattening, the abovementioned longitudinal edges can be formed or limited on the one hand and, on the other hand, can be replaced by a suitable design or arrangement of the flats, the rigidity can be further increased and it can be advantageous space conditions for the welding and / or arranging adjacent struts create.

It is also advantageous if the diagonal strut has two longitudinal outer sides pointing away from one another, preferably flat flattenings. Such a diagonal strut is flexible and can be easily and easily assemble or weld.

According to an advantageous embodiment of the invention can be provided that the diagonal strut in the area between the flats has a designed as a circular arc or elliptical arc outer contour.

According to an advantageous development, the diagonal strut designed as a tube can have a smaller wall thickness in the region of the flattening or the flattening than the wall thickness in the adjacent or intermediate wall regions.

According to a particularly advantageous embodiment, it can be provided that the diagonal strut has an outer thickness in a cross section perpendicular to its longitudinal axis and the flattening has a width whose ratio is greater than or equal to 2.0.

According to a further advantageous embodiment, it can be provided that viewed in a cross section perpendicular to its longitudinal axis, the diagonal strut has an outer width and an outer thickness whose ratio greater than or equal to 1.25, preferably greater than or equal to 1.5.

Further features, aspects and advantages of the invention can be taken from the following description part, in which an advantageous embodiment of the invention is described with reference to the figures.

Fig. 1

Eine Draufsicht auf einen Gitterträger;

Fig. 2

in einem vergrößerten Längsschnitt entlang der Schnittebene 2-2 in Fig. 1 einen Teilabschnitt des Gitterträgers im Bereich dessen Quermitte;

Fig. 3

in einem stark vergrößerten Längsschnitt entlang der Schnittebene 3-3 in Fig.1 einen Teilabschnitt des Gitterträgers im Bereich des dort rechts gezeigten Obergurts;

Fig. 4

einen vergrößerten Querschnitt des Gitterträgers gemäß Fig. 1 entlang der Schnittebene 4-4 im Bereich der Quermitte einer der Diagonalstreben;

Fig. 5

einen stark vergrößerten Querschnitt einer der Diagonalstreben entlang der Schnittebene 5-5 in Fig. 1.

Show it:

Fig. 1

A top view of a lattice girder;

Fig. 2

in an enlarged longitudinal section along the sectional plane 2-2 in Figure 1 a portion of the lattice girder in the region of the transverse center.

Fig. 3

in a greatly enlarged longitudinal section along the sectional plane 3-3 in Figure 1 a portion of the lattice girder in the region of the upper belt shown there on the right;

Fig. 4

an enlarged cross section of the lattice girder according to Figure 1 along the cutting plane 4-4 in the region of the transverse center of one of the diagonal struts.

Fig. 5

a greatly enlarged cross section of one of the diagonal struts along the sectional plane 5-5 in Fig. 1st

The lattice girder 20 shown in FIG. 1 comprises a top flange 21, a bottom flange 23, three spacer struts 24.1, 24.2, 24.3 and four diagonal struts 26; 26.1, 26.2, 26.3, 26.4. The upper belt 21 and the lower belt 23 are parallel arranged to each other and at a transverse distance 22, which corresponds approximately to the length of the intermediate spacer struts 24.1, 24.2, 24.3.

The upper flange 21 and the lower flange 23 are each designed as straight, equal length, round longitudinal tubes, which are open at their respective ends to the outside. In the region of the ends of the upper flange 21 and the lower flange 23, these are welded to a spacer strut 24.1 and one of them spaced apart at a longitudinal distance 48 and parallel to this spacer strut 24.2 to form a rigid frame 25. The spacer struts 24.1 and 24.2 are arranged perpendicular to the upper flange 21 and the lower flange 23.

In the longitudinal center of the upper flange 21 and the lower flange 23 is also interposed and in the plane defined by the upper flange 21 and the lower flange 23 level 47, another spacer strut 24.3 welded, which is also perpendicular to the upper flange 21 and the lower flange 23.

The spacer struts 24.1, 24.2 and 24.3 here are each round tubes.

As a further stiffening elements are between the upper flange 21 and the lower flange 23 here four diagonal struts 26; 26.1, 26.2, 26.3, 26.4 also arranged in between and in the plane defined by the upper flange 21 and the lower flange 23 level 47 and welded to the upper flange 21 and the lower flange 23 at their respective ends 27.1, 27.2 (welds 44).

The diagonal struts 26; 26.1, 26.2, 26.3, 26.4 are in this case arranged such that two diagonal struts 26.1, 26.2 or 26.3, 26.4 are respectively arranged between two spacer struts 24.1, 24.3 and 24.3, 24.2.

Within the part-frame formed by the spacer struts 24.1, 24.3 or 24.3, 24.2 and the upper flange 21 and the lower flange 23, the diagonal struts 26.1, 26.2 and 26.3, 26.4 are arranged in a V-shape. Overall, the diagonal braces 26; 26.1, 26.2, 26.3, 26.4 arranged in a zigzag or truss-like manner between the upper flange 21 and the lower flange 23.

The diagonal struts 26; 26.1, 26.2, 26.3, 26.4 are here also designed as straight continuous tubes 29. However, these each have in a section 28.1 to 28.4 transverse to its longitudinal axis 40 on an oval or elliptical ring cross-section 30.1 to 30.4, the longitudinal axis 31 is arranged parallel to the plane defined by the upper flange 21 and the lower flange 23 level 47, the Here, preferably, the longitudinal axis 51 of the upper flange 21 and the longitudinal axis 53 of the lower flange 23 contains.

The exact cross section 30.4 perpendicular to the longitudinal axis 40 of the diagonal struts 26 is shown in Figure 5. As can be seen, the oval or elliptical cross section 30.4 is designed symmetrically to its longitudinal axis 31 and symmetrical to its transverse axis 32.

The diagonal strut 26 has on two facing away from each other longitudinal outer sides 49.1, 49.2 flat flats 35.1, 35.2, each by the longitudinal direction 40 of Diagonal strut 26 extending edges 34.1 to 34.4 are bounded laterally.

In the outer peripheral region between the flats 35.1 and 35.2, the diagonal strut 26 has an outer contour designed here in each case as circular arc 37.1, 37.2. These outer contours are thus each designed with a radius.

However, it is understood that these outer contours can also be designed alternatively, additionally or only with an elliptical arc.

The diagonal strut 26 configured as a tube 29 has a wall thickness 39 in the region between the flats 35.1, 35.2 which is greater than the wall thickness 38 in the region of the flats 35.1, 35.2. Furthermore, viewed in a cross section 28.4 perpendicular to its longitudinal axis 40, the diagonal strut 26 has an outer width 41 and an outer thickness 43, the ratio of which is approximately 1.5 here. In addition, the ratio of the outer thickness 43 and the width 42 of the flats 35.1, 35.2 is about 2.0.

Due to the advantageous cross-sectional design and arrangement of the diagonal struts 26; 26.1, 26.2, 26.3, 26.4 can be welded to the top chord 21 and the bottom chord 23 manually and with great ease either manually or with the help of welding robots. It can be deliberately omitted in the hard to reach areas, while in the other areas on a defined length or in a defined area a weld can be placed or multiple welds can be placed.

An advantageous orientation during welding allow the longitudinal edges 34.1 to 34.4, which limit the flats 35.1 and 35.2 laterally. Because these edges 34.1 to 34.4 form markings, up to which, starting from the here arcuate longitudinal edges or outer contours, a weld seam precisely, d. H. can be placed defined. In the embodiment shown, each diagonal strut is provided at both ends 27.1, 27.2 thereof, in each case in the areas 36.1, 36.2 between the flats 35.1, 35.2, with a continuous weld 44. In the hard to reach areas, preferably in those corner areas where the diagonal struts 26; 26.1, 26.2, 26.3, 26.4 abut at an acute angle to the upper flange 21 and to the lower flange 23, d. H. In the area of at least one of the flats 35.1, 35.2, there remains a region 45 free of weld seams. It is understood, however, that in the regions of both flats 35.1 and 35.2, a region free of weld seams can each remain.

For further stiffening of the lattice girder 20, it can be welded to a triangular or trapezoidal stiffening plate 46 in the region of its longitudinal ends and there in the region in which the diagonal struts 26.1, 26.4 and the spacer struts 24.1, 24.2 are each arranged at an acute angle be.

The lattice girder 20 shown in the figures is made of aluminum. In this case, the cross-sectional profile of the diagonal struts 26; 26.1, 26.2, 26.3, 26.4 are produced in a particularly advantageous manner by the extrusion process. It is understood, however, that the lattice girder forming parts also made Steel or other suitable materials or material combinations may be formed.

E N G L I S H E S T E

20

girder

21

upper chord

22

transverse distance

23

lower chord

24.1

spacer strut

24.2

spacer strut

24.3

spacer strut

25

frame

26

diagonal strut

26.1

diagonal strut

26.2

diagonal strut

26.3

diagonal strut

26.4

diagonal strut

27.1

End of 26

27.2

End of 26

28.1

cut

28.2

cut

28.3

cut

28.4

cut

29

pipe

30.1

(Ring) wire gauge

30.2

(Ring) wire gauge

30.3

(Ring) wire gauge

30.4

(Ring) wire gauge

31

Longitudinal axis of 30

32

Transverse axis of 30

33

Outer circumference of 26

34.1

edge

34.2

edge

34.3

edge

34.4

edge

35.1

flattening

35.2

flattening

36.1

Area

36.2

Area

37.1

arc

37.2

arc

38

wall thickness

39

wall thickness

40

Longitudinal axis of 26

41

Outside width of 26

42

Width of 35.1, 35.2

43

Outer thickness of 26

44

Weld

45

Weld-free area

46

gusset

47

level

48

longitudinal distance

49.1

External longitudinal side

49.2

External longitudinal side

51

Longitudinal axis of 21

53

Longitudinal axis of 23

Claims (10)

1. Truss (20) for scaffolding, roof constructions, stands, stairs, stages and the like, with a top chord (21) and a bottom chord (23) arranged parallel thereto and at a transverse spacing (22), and with at least two spacer struts (24.1, 24.2, 24.3), which are arranged parallel to one another and at a longitudinal spacing (48) and which are welded to the top chord (21) and the bottom chord (23) to form a rigid frame (25) and are preferably constructed perpendicularly to the top chord (21) and the bottom chord (23), and with at least one diagonal strut (26; 26.1, 26.2, 26.3, 26.4), which is arranged between the top chord (21) and the bottom chord (23) and which is welded at its ends (27.1, 27.2) to the top chord (21) and the bottom chord (23), characterised in that the diagonal strut (26; 26.1, 26.2, 26.3, 26.4) has an oval or elliptical cross-section (30.1 to 30.4) at least at its ends (27.1, 27.2) in a section (28.1 to 28.4) transverse to its longitudinal axis (40), the longitudinal axis (31) of the cross-section being arranged parallel to the plane (47) spanned by the top chord (21) and the bottom chord (23).
2. Truss according to claim 1, characterised in that the diagonal strut (26; 26.1, 26.2, 26.3, 26.4) is formed as a tube (29) and has an oval or elliptical annular cross-section (30.1 to 30.4) at least at its ends (27.1, 27.2) in a section (28.1 to 28.4) transverse to its longitudinal axis (40).
3. Truss according to claim 1 or 2, characterised in that the oval or elliptical cross-section (30.1 to 30.4) is formed symmetrically to its longitudinal axis (31) and/or transverse axis (32).
4. Truss according to one of claims 1 to 3, characterised in that the diagonal strut (26; 26.1, 26.2, 26.3, 26.4) has at its outer circumference (33) edges (34.1 to 34.4) extending in its longitudinal direction (40).
5. Truss according to one of claims 1 to 4, characterised in that the diagonal strut (26; 26.1, 26.2, 26.3, 26.4) has a flattening (35.1, 35.2) on at least one of its sides associated with its longitudinal axis (31).
6. Truss according to one of claims 1 to 5, characterised in that the diagonal strut (26; 26.1, 26.2, 26.3, 26.4) has two flattenings (35.1, 35.2) on two longitudinal outer sides (49.1, 49.2) facing away from one another.
7. Truss according to claim 5 or 6, characterised in that the diagonal strut (26; 26.1, 26.2, 26.3, 26.4) has in a region (26.1) between the flattenings (35.1, 35.2) an outer contour formed as an arc (37.1, 37.2) of a circle or an arc of an ellipse.
8. Truss according to one of claims 5 to 7, characterised in that the diagonal strut (26; 26.1, 26.2, 26.3, 26.4) formed as a tube (29) has in the region of the flattening (35.1, 35.2) or the flattenings (35.1, 35.2) a wall thickness (38) which is smaller than the wall thickness (39) in the adjoining or intermediate wall mediums.
9. Truss according to one of claims 1 to 8, characterised in that the diagonal strut (26; 26.1, 26.2, 26.3, 26.4), considered in a cross-section (28.4) perpendicular to its longitudinal axis (40), has an outer thickness (43) and the flattening (35.1, 35.2) has a width (42), the ratio of which is greater than or equal to 2.0.
10. Truss according to one of claims 1 to 9, characterised in that the diagonal strut (26; 26.1, 26.2, 26.3, 26.4), considered in a cross-section (28.4) perpendicular to its longitudinal axis (40), has an outer width (41) and an outer thickness (43), the ratio of which is greater than or equal to 1.25, preferably greater than or equal to 1.5.

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