Truss device

Abstract

A truss arrangement comprises a set of elongate tube bodies (10) extending parallel to one another in the longitudinal direction and connected spatially spaced apart from one another by means of rods (30). The pipe body (10) is provided or at least can be provided with a connecting device (20) at the opposite outer end for releasable connection with a pipe body of another truss device. The rod (30) has a polygonal cross-section and is connected on its end face substantially along at least one side of the periphery of the cross-section with an adjacent tube body by a connection that is linear at least in projection.

Description

Technical Field

[0001] The present invention relates to a truss device, which comprises a group of slender tubes, which extend parallel to each other in the longitudinal direction and are spatially connected to each other by rods, wherein the tubes are provided with, or at least capable of being provided with, connecting devices at opposite outer ends for releasably connecting with the tubes of another truss device. Background Art

[0002] Such truss arrangements, often referred to as trusses, are generally used to construct temporary, semi-permanent or permanent structures, for example in stage construction and / or scenery construction. In this case, a plurality of such truss arrangements are connected to one another via manually deployable and releasable connections, optionally also via corner elements. The structures thus formed are frequently used as mounting bases for technical equipment, such as spotlights and loudspeakers, and for constructing optional temporary support structures and walls.

[0003] For example, a known truss is described in European patent application EP1 884 605. This document describes three parallel tubes, which are connected to each other by a cylindrical rod system. The tubes have a cup-shaped structure at their outer ends, which can be connected to a corresponding cup-shaped structure at the outer end of another truss by an adapted double-sided wedge-shaped component. When manufacturing this truss, aluminum parts are usually used for both the tubes and the rods. These parts are usually welded together by hand and then assembled into the final truss device.

[0004] One disadvantage of the known trusses is that their manufacture requires specialist skills and craftsmanship, particularly with regard to the numerous welded connections around the bars, which must be made manually and are therefore time consuming and prone to problems. Summary of the invention

[0005] One of the objects of the present invention is to provide a truss device of the type mentioned above which is significantly simpler to manufacture and which, for this reason among other things, is more suitable for automated production.

[0006] To achieve the above-mentioned purpose, the truss device of the type described above has the characteristics of the present invention: the rod has a polygonal cross-section and is connected to the adjacent tube body along a connection that is linear at least in projection on the end face, and the linear connection coincides with the edge of the cross-section, and the connections of the multiple rods connected to the tube body are aligned with each other.

[0007] By using substantially straight connections, rather than curved connections as in the bars of known trusses, and by aligning these straight connections with one another, the connection between the bars and the tube can be arranged by one or more substantially linear, smooth movements. This not only requires less skill from the technician, but the process is also more easily automated. In a particular embodiment, a motion system (robot) with only four axes of freedom is sufficient for welding such a truss arrangement. In contrast, for the welding of round bars of known truss arrangements, six axes of drive are required to achieve full-range welding of the bars.

[0008] Since there are only linear connections in the present invention, at least in projection, more space is provided inside the truss device for manipulating a welding torch, etc., in order to actually realize the connection. All of this not only makes the manufacture of the truss device less demanding in terms of manual craftsmanship, but also enables faster and more reliable production, whether it is manual or fully automated, and partly for this reason, the manufacturing cost is also lower.

[0009] A preferred embodiment of the truss device has the following characteristics: the rods are connected to the group of tubes along linear connections at least in projection on opposite end faces, each linear connection coinciding with an edge of the cross section of the corresponding rod, and the corresponding connections of the rods are aligned with each other. Here, the rods are connected to one of the tubes of the group in a corresponding manner at both outer ends.

[0010] A particular embodiment of the truss device has the following features of the invention: each rod is connected to a tube body in the group of tube bodies along a first connection that is at least linear in projection and a second connection that is at least linear in projection, respectively, wherein the first connections of the rods are aligned with each other, the second connections of the rods are aligned with each other, and the first connection and the second connection are parallel to each other.

[0011] Since the connections of the first rod and the second rod are respectively aligned with each other, the relevant connections can be realized successively in a relatively smooth process. This applies to the first connection and the second connection of the rod to the tube body. Since they are parallel to each other, if necessary, the connection can be realized on both sides of the rod in the same process, which saves costly time and operating steps. The first connection and the second connection are preferably parallel to the longitudinal direction of the tube body.

[0012] Although in principle any fully or partially polygonal cross section can be used, another specific embodiment of the truss device has the following features according to the invention: the rod has a rectangular, in particular square, cross section. The advantage of a rectangular or square cross section is that its peripheral edges can be reached along three orthogonal axes. Solid rods can be used here, although another preferred embodiment of the truss device has the following features according to the invention: the rod comprises a hollow tubular profile. Hollow tubular profiles not only reduce weight and material costs while maintaining strength, but also make such rods easier to heat weld due to their lower internal heat dissipation.

[0013] In a further preferred embodiment, the truss device is characterized in that the tubes and the bars are made of the same material, in particular of metal, such as steel or aluminum, and are connected to one another at least substantially only along linear connections. These linear connections can be arranged by machine in a relatively simple manner, in particular by robotic means, by gluing or welding. In order to increase the bending stability and strength, a further preferred embodiment of the truss device has the following features according to the invention: the tubes are connected by the bars in a cross-shaped manner.

[0014] Another particular embodiment of the truss device is characterized in that the tubular body is accommodated at its end faces in a common end frame and that the tubular body and the end frame are connected to one another along at least one further connection, which is at least linear in projection and is oriented parallel to the connection of at least one rod element to a tubular body, in particular aligned with this connection.

[0015] Such an end frame has a dual function. During the manufacturing process, the tubes are thereby held and fixed at the correct mutual distance and position. Once all components are connected to one another, the end frame also increases the lateral strength, torsional rigidity and stability of the device. Likewise, making the connection to the end frame parallel or even aligned with the connection to the rods enables this connection to be achieved in a relatively simple manner in one centralized processing step.

[0016] In another preferred embodiment, the truss device is further characterized in that each rod is connected to one of the tubes of the set along a first at least linear connection in projection and a second at least linear connection in projection, respectively, wherein the first connection and the second connection of the rod are respectively aligned with another at least linear connection in projection of the end frame to the tube, and the first, second and further connections are parallel to each other. Thus, the connection of the end frame can also be realized on both sides in a practical manner similar to the rod itself.

[0017] In this latter aspect, a further preferred embodiment of the truss device has the following features according to the invention: the tube body and the end frames are made of the same metal, in particular of aluminum, and are at least substantially welded to one another only via connections which are linear at least in projection. As a result, the arrangement of end frames, tube body and bars can be completely assembled by a kinematic system having only four axes. This results in considerable simplification and cost savings, especially in terms of automation, compared to previously required robot systems.

[0018] In a particular embodiment, the truss device is characterized in that the end frames are formed in an integral, monolithic manner, in particular obtained by extrusion or casting. In practice, it has been found that such a more or less solid, monolithic component is very suitable for the relative lateral positioning of the tubes and provides a particularly high stability for the whole. Here, a clear stop is preferably provided between each tube and the end frame, which stop also provides the correct axial position of the tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will now be further described with reference to an exemplary embodiment and the associated drawings.

[0020] In the figure:

[0021] Figure 1 is an isometric view of an exemplary embodiment of a truss device according to the present invention;

[0022] Figure 2 yes Figure 1 Sectional view of the middle truss device along line XX;

[0023] Figure 3 yes Figure 1 Front view of the mid-truss assembly.

[0024] It should also be noted that these drawings are purely schematic and are not always drawn to scale. For the sake of clarity, some dimensions may be exaggerated to a certain extent. The same reference numerals in the drawings represent corresponding parts.

[0025] Figure 1 An exemplary embodiment of a truss device (also referred to as a truss) according to the invention is shown in an isometric view. The device comprises four tubes 10 extending axially parallel to each other and located at the corners of a virtual square in cross section. The tubes are provided with cup-shaped connecting means 20 at their opposite outer ends, the cup-shaped connecting means being tapered inside. Accommodated in the cup-shaped structure is a connecting body (not shown in the figure, but fully understood by a person skilled in the art) which has a complementary taper on the outside on both sides, so as to enable a rigid and reliable connection to the corresponding outer end of another truss body.

[0026] Both the tube body 10 and the cup-shaped structure 20 are made completely of aluminum, although other suitable materials may also be used, in particular metals such as steel or plastics, in particular fiber-reinforced plastics. The outer ends of the tube body 10 are accommodated in end frames 30, which not only provide additional rigidity, strength and stability to the final product, but also precisely align and fix the tube bodies 10 with each other in the transverse direction during production. A distinct stop may optionally be provided between the tube body and the end frame in order to also achieve correct positioning in the axial direction. Figure 3 Such an end frame 30 is further shown in the front view of the truss arrangement. Here a one-piece solid aluminium body is used, for example obtained by extrusion or moulding.

[0027] In order to achieve the overall strength of the truss device, in particular the bending stiffness, the tubes are connected to each other in a cross-shaped manner by means of a rod system 40. According to the invention, rods 40 with a polygonal cross section are used here so that the connection between the rod 40 and the adjacent tube 10 can be achieved on one or more straight peripheral sides thereof. In this case, the rods 40 used for this purpose are essentially rectangular tubular bodies 40, see Figure 2 These bars are welded at their outer ends to the adjacent tube bodies only by linear connections along one or more sides of their polygonal cross-section.

[0028] For the purpose of illustration, the embodiment of such connection is shown by dashed lines I, II, and III in the figure, wherein the transverse connection transverse to the long axis direction of the truss body extends along the curve of the tube body 10, but is still linear in projection. In addition, in addition to the welding connection, bonding can also be performed between the rod 40 and the tube body 10 according to the raw materials of the rod and the tube body.

[0029] As indicated by the line I in the figure, the connections along which the welded connections of adjacent bars 40 are aligned with one another in the axial direction. In this embodiment, the welded connections between the end frame 30 and the tubular body 10 also lie on the same line I. Due to the linearity of the mutual welding between the various components of the truss arrangement, in particular between the bars and the tubular body, the truss body can be manufactured by machine in a relatively simple manner. This is particularly true if the welded connections between consecutive bars extend parallel to one another in the same direction or, as in this case, even aligned with one another on a line I. It is therefore particularly simple to automate the production process to a large extent, since a kinematic system having only four axes is sufficient to move the welding torch along all the peripheral edges of the bars 40 and thus to achieve reliable linear welding there.

[0030] Although the present invention has been further described with reference to only one exemplary embodiment, it is obvious that the present invention is by no means limited thereto. On the contrary, for those skilled in the art, there are still many variations and embodiments within the scope of the present invention.

Claims

1. A truss device comprising a plurality of elongated tubes extending longitudinally parallel to each other and spaced apart from each other by rods, wherein the tubes are provided with, or at least capable of being provided with, connection means at opposite outer ends for releasably connecting with the tubes of another truss device, It is characterized in that The rod has a polygonal cross section and is connected to the adjacent tube along a connection that is linear at least in projection on the end face, the linear connection coincides with the edge of the cross section, and the connections of the multiple rods connected to the tube are aligned with each other.

2. The truss device according to claim 1, It is characterized in that The rods are connected to the group of tubes along connections that are linear at least in projection on opposite end faces, each linear connection coincides with an edge of a corresponding cross section of the rod, and corresponding connections of the rods are aligned with each other.

3. The truss device according to claim 1 or 2, It is characterized in that Each rod is connected to one of the tubes in the group along a first connection that is at least linear in projection and a second connection that is at least linear in projection, wherein the first connections of the rods are aligned with each other, the second connections of the rods are aligned with each other, and the first connection and the second connection are parallel to each other.

4. The truss device according to claim 3, It is characterized in that The first connection and the second connection are parallel to the longitudinal direction of the tube body.

5. Truss device according to one or more of the preceding claims, It is characterized in that The rod has a rectangular, in particular square, cross section.

6. Truss device according to one or more of the preceding claims, It is characterized in that The rod comprises a hollow tubular profile.

7. Truss device according to one or more of the preceding claims, It is characterized in that The tube body and the rod element are made of the same material, in particular of metal, such as steel or aluminum, and are connected to one another at least substantially only along a linear connection.

8. Truss device according to one or more of the preceding claims, It is characterized in that The tubes are connected in a cross manner by rods.

9. Truss device according to one or more of the preceding claims, It is characterized in that The tubular body is accommodated at its end faces in a common end frame, and the tubular body and the end frame are connected to each other along at least one further connection, which is linear at least in projection and is oriented parallel to the connection of at least one rod element to one tubular body, in particular aligned with this connection.

10. The truss device according to claim 9, It is characterized in that Each rod is connected to one of the tube bodies in the group along a first connection that is at least linear in projection and a second connection that is at least linear in projection, respectively, wherein the first connection and the second connection of the rod are respectively aligned with another connection that is at least linear in projection between the end frame and the tube body, and the first, second and further connections are parallel to each other.

11. The truss device according to claim 10, It is characterized in that The further at least linear connection in projection is substantially aligned with the first at least linear connection in projection and the second at least linear connection in projection.

12. Truss arrangement according to one or more of claims 9 to 11, It is characterized in that The tubular body and the end frame are made of the same metal, in particular of aluminum, and are welded to one another at least substantially exclusively via a connection which is linear at least in projection.

13. Truss arrangement according to one or more of claims 9 to 12, It is characterized in that The end frames are formed in a one-piece, monolithic manner, in particular by extrusion or casting.

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