EP1291470B1

EP1291470B1 - Truss construction and coupling part, basic element and coupling element for application therein

Info

Publication number: EP1291470B1
Application number: EP02078705A
Authority: EP
Inventors: Marc Hendriks; Johann Otto Rudolf Stuut; Ivo Ate Mulder
Original assignee: PROLYTE BEHEER BV
Current assignee: PROLYTE BEHEER BV
Priority date: 2001-09-06
Filing date: 2002-09-05
Publication date: 2007-08-29
Anticipated expiration: 2022-09-05
Also published as: PT1291470E; ES2292690T3; DK1291470T3; ATE371776T1; EP1291470A1; NL1018901C2; DE60222064T2; DE60222064D1

Abstract

A truss construction comprises a first truss and at least one further truss, wherein the trusses are fixed to each other via a coupling part (20). The coupling part herein comprises a basic element (21) having on a first side connecting means (52,55,56,36) for a manually releasable connection to a first coupling element (54A..D) and on at least one further side connecting means (52,55,56,36) for a manually releasable connection to a further coupling element (54A..D). Each coupling element (54A..D) is provided on a side remote from the basic element coupling members (30) for a releasable connection to a truss, which is connected to the basic element via said coupling members. <IMAGE>

Description

The present invention relates to a truss construction comprising a first truss and at least one further truss, wherein the trusses are fixed to each other via a coupling part, wherein the coupling part comprises a basic element having on a first side connecting means for a manually releasable connection to a first coupling element and on at least one further side connecting means for a manually releasable connection to a further coupling element, wherein each coupling element comprises on a side remote from the basic element coupling members for a releasable connection to a truss, wherein the first truss is connected to the basic element via the first coupling element and wherein the at least one further truss is connected to the basic element via the at least one further coupling element, wherein at least the first side of the basic element comprises connecting pieces which form the corners of an imaginary square and wherein the connecting pieces comprise the connecting means.
Such a truss construction is known from European patent application 0.307.718 . A problem of the known truss construction is that it's basic element is less suitable to be connected to a triangular truss since the connecting pieces are arranged in an imaginary square.
It is an object of the invention to improve the truss construction in this respect.
To this end a truss construction of the type stated in the preamble has the feature according to the invention that the basic element of the coupling part comprises a number of tube parts which form the edges of an imaginary cube and which are mutually coupled at corner points of the cube via a respective connecting piece, and that at least on the first and further side of the basic element at least one additional connecting piece is arranged which forms an imaginary triangle, at least in projection, with two diametrically opposite connecting pieces. In this embodiment use is made of a cube as the basic form for the basic element, which is assembled from tubes and connecting pieces. The connecting pieces comprise connecting means for the connecting elements. In order to also allow connection of triangular trusses, there is added on at least one side of the basic element a connecting piece which comprises connecting means at the position of the vertex of the triangular truss for coupling. A triangular truss or a square truss can thus easily and readily be connected to the first or further side of the basic element. This facilitates the assembling of truss constructions, and only one type of basic element has to be kept in stock for connecting both square and triangular trusses.
In a further particular embodiment the triangle is an isosceles triangle, and more particularly an equilateral triangle. In the latter case the additional connecting means are then situated, assuming a basic element with edges of a length L, at the position √¾. L. For the directions in which a triangular truss is desired, coupling elements are connected to the basic element via these additional connecting means and the truss in question is coupled to these coupling elements. Triangular trusses can thus be connected from a cubic basic form, optionally in combination with square and straight trusses.
In a particular embodiment the truss construction according to the invention has the feature that at least one of the fixed trusses has an at least substantially triangular cross-section and that the basic element comprises the connecting means in at least two at least substantially mutually orthogonal planes. In a modular manner this embodiment creates a unique transition between triangular trusses in mutually orthogonal directions, if desired in combination with other types of trusses, such as square and straight ones. All manner of right-angled corners with one or more triangular trusses can thus be realized owing to the above described flexibility and adjustability of the coupling part.
In a further particular embodiment the truss construction according to the invention has the feature that the basic element comprises the connecting means in six at least substantially mutually orthogonal planes. In this case all possible right-angled connections of trusses in three dimensions can be realized, wherein a coupling element is arranged in the directions in which a connection must actually be made.
A further embodiment of the truss construction according to the invention has the feature that the coupling elements comprise a number of tube parts forming a continuation of the truss connected thereto, and that on a side directed toward the basic element the tube parts are connected thereto by means of a threaded connection, and on a side remote from the basic element they carry a coupling member. Because the coupling elements form as it were a continuation of the trusses connected thereto, the mutual connection can be achieved while retaining strength, rigidity and reliability, so that the final construction is fully loadable. The mutual connection between coupling element and basic element is a threaded connection and is realized beforehand using appropriate tools. A further embodiment of the truss connection according to the invention has in this respect the feature that the connecting means comprise bores in which an internal thread is arranged to close-fittingly receive therein an external thread of a threaded end extending from a coupling element.
A particular preferred embodiment of the truss construction according to the invention is characterized in that the tube parts are mutually connected in a polygonal relation, and particularly in that the relation of at least one of the coupling elements comprises a triangular relation. By arranging the orthogonal relation in the coupling element in a manner corresponding with the truss for connecting hereto, jigs and/or additional tolerances and fine adjustments are unnecessary owing to the thus obtained dimensionally stable and exact alignment.
Although the connection to the trusses can be realized in different ways, use is preferably made of a releasable rapid-action coupling. A further preferred embodiment of the truss construction according to the invention has in this respect the feature that the coupling member comprises a hollow bush body open on at least one side, with an at least partly conical inner surface on which a complementary outer surface of a coupling body lies in fitting manner, that the bush body and the coupling body are fixed in mutually releasable manner by means of a locking pin and that the coupling body is firmly connected to a truss. Such a conical bush coupling is self-aligning and can be embodied in clearance-free and rigid manner without great effort. In a further embodiment the truss construction is characterized herein in that the trusses are also provided on their outer end with coupling members in the form of a hollow bush body open on at least one side with an at least partly conical inner surface on which a complementary outer surface of a coupling body lies in fitting manner, that the bush body and the coupling body are connected in mutually releasable yet firm manner by means of a locking pin. In this case coupling part and truss take a homomorphic form in respect of the coupling, and by interposing such a symmetrical coupling body a clearance-free, rigid and, partly for this reason, exceptionally strong connection can always be made. Simply arranging and removing the locking pin is sufficient to fix and respectively release this connection.
The invention also provides a truss construction comprising a first truss and at least one further truss, wherein the trusses are fixed to each other via a coupling part, wherein the coupling part comprises a basic element having on a first side connecting means for a manually releasable connection to a first coupling element and on at least one further side connecting means for a manually releasable connection to a further coupling element, wherein each coupling element comprises on a side remote from the basic element coupling members for a releasable connection to a truss, wherein the first truss is connected to the basic element via the first coupling element and wherein the at least one further truss is connected to the basic element via the at least one further coupling element, characterized in that the basic element comprises a number of tube parts which form the sides of an imaginary pyramid and which are mutually coupled at corner points hereof via a connecting piece, that the connecting pieces comprise the connecting means, that the pyramid has a square base, and that there is arranged at least practically halfway along at least one of the sides of the base a first further connecting piece which, at least in projection, forms a triangle with diametrically opposite connecting pieces in the base.
By making use herein of a pyramidal structure of the basic element there is optimal connection to the cross-section of triangular trusses which have to be mutually coupled. In its basic form such a coupling part can mutually connect four trusses. A square truss can be coupled on if desired on the base side of the coupling part. In practice this could for instance be an upright in the total truss construction, which thus imparts more strength to the whole than a comparably dimensioned triangle truss in the same position. A square base moreover provides an extra side in the structure of the basic element for connection of an additional truss. A triangular or square truss can be coupled on as desired on the base side, which makes the whole all the more flexible.
A very particular preferred embodiment of the truss construction according to the invention is characterized in that, in a direction substantially transversely of the base of the pyramid, a second further connecting piece is connected to the first further connecting piece and that the second further connecting piece is arranged at least practically at the same distance from the base as the connecting piece which forms a vertex of the pyramid, and which, at least in projection, forms a triangle with two diametrically opposite connecting pieces in the base of the pyramid. In this embodiment the second further connecting piece provides a basis for further connecting means so that an extra truss can be coupled on at the side of the basic element where this second further connecting piece is arranged. Assuming a rectangular base, a total of six connections is thus possible in orthogonal directions. The basic form of the basic element herein remains a pyramid structure however, and thus fits in optimally with the design of triangular trusses. This is not only a significant advantage from a mechanical-physical viewpoint, but it also provides aesthetic advantages in that the coupling part thus remains relatively slender and does not protrude, or hardly so, in a construction of mainly or only triangular trusses. The slender construction furthermore ensures a relatively low weight, which provides important ergonomic advantages. base side of the coupling part. In practice this could for instance be an upright in the total truss construction, which thus imparts more strength to the whole than a comparably dimensioned triangle truss in the same position. A square base moreover provides an extra side in the structure of the basic element for connection of an additional truss. A further particular embodiment of the truss construction according to the invention has in this respect the feature that there is arranged at least practically halfway along at least one of the sides of the base a first further connecting piece which, at least in projection, forms a triangle with diametrically opposite connecting pieces in the base. In this case a triangular or square truss can be coupled on as desired on the base side, which makes the whole all the more flexible.
A very particular preferred embodiment of the truss construction according to the invention is characterized in that, in a direction substantially transversely of the base of the pyramid, a second further connecting piece is connected to the first further connecting piece and that the second further connecting piece is arranged at least practically at the same distance from the base as the connecting piece which forms a vertex of the pyramid, and which, at least in projection, forms a triangle with two diametrically opposite connecting pieces in the base of the pyramid. In this embodiment the second further connecting piece provides a basis for further connecting means so that an extra truss can be coupled on at the side of the basic element where this second further connecting piece is arranged. Assuming a rectangular base, a total of six connections is thus possible in orthogonal directions. The basic form of the basic element herein remains a pyramid structure however, and thus fits in optimally with the design of triangular trusses. This is not only a significant advantage from a mechanical-physical viewpoint, but it also provides aesthetic advantages in that the coupling part thus remains relatively slender and does not protrude, or hardly so, in a construction of mainly or only triangular trusses. The slender construction furthermore ensures a relatively low weight, which provides important ergonomic advantages.
The invention also relates to a coupling part, basic element and a coupling element for application in the above described truss construction according to the invention, and will now be further elucidated on the basis of a number of embodiments and an associated drawing. In the drawing:

figure 1: shows a first embodiment of a truss construction according to the invention;
figure 2: shows a perspective view of a releasable rapid-action coupling applied in the truss construction of the other figures;
figure 3: shows a second embodiment of a truss construction according to the invention; and
figure 4: shows a third embodiment of a truss construction according to the invention.

Corresponding parts are designated as far as possible in the figures with the same reference numerals.
Figure 1 shows a truss construction according to a first embodiment of the invention. The truss construction here comprises four triangular trusses 13 which are coupled mutually and to a square truss 14 via a coupling part 20. The trusses each comprise a number of parallel tubes 10 which typically have, depending on the desired loadability, a diameter of 30-50 mm and between which a number of thinner bars 11 is welded to give the desired rigidity, strength and shape-retention thereto. All components are formed in this embodiment from aluminium, wherein for the hollow parts use is made of a relatively thick wall of 1.5-4.0 mm to ensure sufficient strength and durability.
For the mutual coupling of the various truss parts, use is made in this embodiment, as it is in the following, of a conical bush coupling which is further shown in figure 2 for the purpose of elucidation. The hollow tube parts 10 are provided on both sides for this purpose with a coupling member 30 in the form of a hollow bush body with an inner surface 31 running over a part of the length thereof. All other truss parts are also provided with such coupling members in order to enable a mutual rapid-action coupling which can be manually arranged and, if desired, released without special tools.
In the cavity of the bush body a complementarily formed coupling body 32 is received which lies close-fittingly therein. Coupling body 32 is symmetrical and has on both sides the same conical progression adapted to the bush bodies 30 with their inner surface 31. The orientation of coupling body 32 itself and the truss parts for connecting is therefore not important for the connection to be made. Transversely of the longitudinal direction of each of the bush bodies 30 and coupling body 32 a slightly conical bore 36 is arranged through both parts, in which bore a similarly slightly conical locking pin 33 is received. This locking pin 33 fixes the whole and is self-tightening owing to the conical progression thereof, so that a firm and clearance-free situation is obtained. Locking pins 33 are in turn secured by a standard cotter pin 34 or nut 35.
The coupling body comprises a basic element 21 which is constructed from a number of tube parts 22 which form the edges of an imaginary cube and which are mutually coupled at the corner points thereof by coupling pieces 23. Coupling pieces 23 are for the greater part solid, rectangular blocks having in each side surface a central bore 25 with an internal screw thread in which is close-fittingly received a threaded end of a screw bolt which extends freely rotatably from a tube part at an outer end thereof. A blind threaded connection can thus be realized between a tube part and coupling piece. Because the outer end of the screw bolt is provided with a socket, torque or other engaging means, and is freely accessible via the bore in the coupling piece, such a threaded connection can be firmly tightened on both sides.
The free bores 25 form connecting means for coupling elements 26 which can be arranged on and released from the sides of the basic element as required in order to mutually connect the desired number of trusses. In this embodiment the coupling elements 26 comprise coupling bushes which are screwed into bores 25 of coupling pieces 23 in the above described manner by means of a screw bolt. On their free end the coupling bushes 26 bear a coupling member adapted to the conical rapid-action coupling which has been further elucidated above with reference to figure 2. A coupling body is received herein and fixed with a locking pin.
So as to also enable coupling of triangular trusses, extra coupling pieces 24 which extend slightly inward are added to the side surfaces of basic element 21. In addition to a number of bores 25 for fixing the adjacent tube parts in the above stated manner, these coupling pieces 24 also comprise a bore 25 at the position of a vertex of the triangular truss for connecting. In this case, assuming an equilateral triangle truss with sides L, typically in the order of 300-600 mm, and a cube-shaped basic element 21 with edges having a corresponding length L as measured in each case to the centre line distance of the component tube parts, this means that the bore in the extra coupling piece 24 lies at a centre line distance of (1 - √¾).L from the adjacent edge. This bore forms part of connecting means for a coupling element 26 to a triangular truss.
Such an additional coupling piece 24 is arranged on each of the side surfaces of basic element 20 so that, in addition to a square truss, a triangular truss can also be connected all round by screwing a coupling element 26 into the indicated threaded holes 25 in coupling pieces 23,24. Where no coupling to a truss is necessary, such a coupling element 26 can be omitted so that no unused coupling elements are visible which would otherwise disrupt the whole. In this case, four triangular trusses 13 as beams and a square truss 14 as upright are thus coupled all round in mutually orthogonal position. The coupling part can thus be adapted in wholly modular and flexible manner to the construction to be realized therewith. It is hereby no longer necessary to hold different coupling parts in stock for each specific situation.
In the just described embodiment of the truss construction according to the invention the orientation of triangular trusses 13 on coupling part 20 is fixed, i.e. with the vertex upward in each case in the given position. A second embodiment of the truss construction according to the invention, further shown in figure 3, offers more flexibility in this respect. The coupling part herein has roughly the same structure as that of the previous example, but in this case not only are additional coupling pieces received in the side surfaces thereof, but also bridges 28 which mutually connect opposite tube parts. Bridges 28 are situated on all sides of the coupling part and each comprise two bores at a centre line distance of (1 - √¾).L from the adjacent tube part, wherein here also L is again the centre line distance between opposite tube parts and the centre line length of a truss side. A triangular truss can hereby be mounted with the vertex upward and, as in the present embodiment, with the vertex downward. Other than in the first embodiment, the coupling part is here applied for the mutual connection of only triangular trusses, namely five pieces in a mutually orthogonal configuration.
Arranged halfway along in at least one of bridges 28 is an extra bore in which a fixing eye 29 is screwed for the purpose of hoisting means. This eye 29 is thus situated at the position of a median of coupling part 20 and provides the option of constructing the truss construction at least partly on the ground and only hoisting it on the eye later.
An implementation of a particular preferred embodiment of the truss construction according to the invention is shown in figure 4 in exploded view, wherein for the sake of clarity the connected trusses are not drawn. In this embodiment the basic element 21 of the coupling part essentially comprises a pyramid structure constructed from eight tube parts 51 mutually connected by means of coupling pieces 52. A structure is chosen in this case with a quadrangular and even square base 53, although a triangular base can in principle also be applied instead for the mutual coupling of only four triangular trusses. For the mutual connection of the coupling pieces and tube parts 51 use is made, as in the foregoing embodiments, of a blind bolt connection by means of freely rotatable bolts 35 which are arranged in the outer end of tube parts 51 and received in a bore 36 with internal screw thread of the coupling pieces. Because screw bolts 35 are provided in their outer end with a socket, torque or other engaging means and this outer end is freely accessible via bore 36 in the coupling piece, such a threaded connection can, despite the concealed arrangement hereof, nevertheless be firmly tightened on both sides.
Halfway along the base there is arranged a first further coupling piece 55 which at least in projection forms an imaginary triangle with two diametrically opposite coupling pieces at the corner points of the base. Bores are situated in the relevant coupling pieces at the position of the corner points of this imaginary triangle. In the primary coupling pieces 52 this is a central bore, in the further coupling piece 55 the bore lies about (1-2).L from a centre line of the adjacent base side of the pyramid structure, wherein L is the length of this side and the length of each of the sides of the formed imaginary triangle. The designated pyramid structure 51,52,55 thus provides the option of mutually orthogonal coupling of four triangular trusses all round in a horizontal plane, and of coupling thereto in a vertical plane of a triangular truss or a square truss as desired. For this purpose the coupling pieces 52,55 are provided in all side surfaces with bores 36 with an internal screw thread which form connecting means for the purpose of coupling elements 54A,B, which are screwed therein with bolts 35 in the same manner as tube parts 51. Coupling elements 54A,B comprise on their free outer end coupling members 30 in the form of hollow bush parts with a conical inner surface, such as were shown in figure 2. A releasable rapid-action coupling is hereby possible to trusses, not further drawn here, which are also provided with such coupling members.
In order to also allow coupling of a truss in a sixth direction, there is arranged transversely of base 53 a second further coupling piece 56 which is connected via a first further tube part 57 to the first further coupling piece 55 and via a second further tube part 58 to the coupling piece 52 forming the vertex of the pyramid. This second further coupling piece 56 also forms an imaginary triangle with the two diametrically opposite coupling pieces in the base of the pyramid structure, so that an additional coupling element 54C can be connected in a sixth direction for the purpose of coupling a further triangular truss in that direction. The second further coupling piece 56 is situated directly in line with the coupling piece 52 forming the vertex of the pyramid, so that a modified coupling element 54D is applied in this direction, one of the legs of this element being correspondingly shorter than in a coupling element 54A in order to engage on the second further coupling piece 56. In order to maintain strength, the second further coupling piece 56 and the vertex coupling piece 52 are manufactured integrally together with the connecting tube part, and are therefore, other than the remaining parts of the basic element, not coupled to each other by means of threaded connections. Triangular trusses can thus be coupled in six mutually orthogonal directions while retaining full strength. The coupling part herein provides a particularly attractive transition from the triangle structure of the trusses to these orthogonal directions. The structure of the trusses as it were runs on into the coupling part, both in the coupling elements and in the basic element thereof, whereby the forces are distributed herein in particularly uniform manner. This latter is further enhanced in that, where necessary, the bars 11 in the trusses are continued into the coupling elements 54 A,D, thus avoiding loss of strength. The coupling part is therefore fully loadable in all directions, adapted to the maximal loadability of the connected trusses. Furthermore, owing to its relatively slender design, the coupling part not only provides a relatively low total weight, which is desirable from an ergonomic viewpoint and with a view to working conditions, but also an aesthetically particularly attractive overall picture.
An additional advantage of the triangular relation arranged in the coupling elements by means of bars is that the coupling members extending therefrom are always precisely aligned relative to the coupling members of the triangular trusses for connecting, which have the same relation. It is not therefore necessary in the field to work with jigs, additional tolerances or other assist means in building a total truss construction.
In this embodiment also an engaging means for hoisting means is arranged centrally in the coupling part, this in the form of an additional coupling part 59 which is connected to the vertex and opposite sides in the base by means of tube parts. This coupling part is also provided with a central bore with an internal screw thread. In this bore can be arranged a hoisting eye, as is also the case in the foregoing embodiment, for hoisting the construction thereon if desired. The invention thus provides a particularly flexible and universally applicable coupling part which can be employed in constructions of many different types.
Although the invention has been further elucidated above with reference to only three embodiments, it will be apparent that the invention is by no means limited thereto. On the contrary, many more variations and embodiments are possible within the scope of the invention. While the shown and further described rapid-action coupling to the trusses is thus particularly reliable and practical, it is not the only manner in which a releasable (rapid-action) coupling to the trusses can be realized within the scope of the invention. A straight bush coupling, male-female, a screw coupling, a bayonet coupling or even a coupling in other manner can for instance also be applied instead. Another material, for instance steel or other lightweight metal (alloy), can also be applied instead of aluminium for all or some of the components, although this will generally result in a higher total weight and/or cost price. In the embodiments almost all component parts of the coupling part are coupled to each other by releasable threaded connections, in particular the tube parts and coupling pieces, although other connections, in particular welded connections, can at least often also be applied instead while retaining the action and functionality of the coupling part.

Claims

Truss construction comprising a first truss (13) and at least one further truss (13), wherein the trusses (13) are fixed to each other via a coupling part (20), wherein the coupling part (20) comprises a basic element (21) having on a first side connecting means (25) for a manually releasable connection to a first coupling element (26) and on at least one further side connecting means (25) for a manually releasable connection to a further coupling element (26), wherein each coupling element (26) comprises on a side remote from the basic element (21) coupling members (30,32) for a releasable connection to a truss (13), wherein the first truss (13) is connected to the basic element (21) via the first coupling element (26) and wherein the at least one further truss (13) is connected to the basic element (21) via the at least one further coupling element (26), wherein at least the first side of the basic element (21) comprises connecting pieces (23) which form the corners of an imaginary square and wherein the connecting pieces (23) comprise the connecting means (25), characterized in that the basic element (21) of the coupling part (20) comprises a number of tube parts (22) which form the edges of an imaginary cube and which are mutually coupled at corner points of the cube via a respective connecting piece (23), and that at least on the first and further side of the basic element (21) at least one additional connecting piece (24) is arranged which forms an imaginary triangle, at least in projection, with two diametrically opposite connecting pieces (23).
Truss construction as claimed in claim 1, characterized in that the triangle is an isosceles triangle, and more particularly an equilateral triangle.
Truss construction as claimed in claim 1 or 2, characterized in that at least one of the fixed trusses (13) has an at least substantially triangular cross-section and that the basic element (21) comprises the connecting means (25) in at least two at least substantially mutually orthogonal planes.
Truss construction as claimed in claim 3, characterized in that the basic element (21) comprises the connecting means (25) in six at least substantially mutually orthogonal planes.
Truss construction as claimed in one or more of the preceding claims, characterized in that the coupling elements (26) comprise a number of tube parts (30) forming a continuation of the truss (13) connected thereto, and that on a side directed toward the basic element (21) the tube parts (30) are connected thereto by means of a threaded connection, and on a side remote from the basic element (21) they carry a coupling member (32).
Truss construction as claimed in claim 5, characterized in that the tube parts (30) are mutually connected in a polygonal relation.
Truss construction as claimed in claim 6, characterized in that the relation of at least one of the coupling elements (26) comprises a triangular relation.
Truss construction as claimed in one or more of the foregoing claims, characterized in that the coupling member (30) comprises a hollow bush body (30) open on at least one side, with an at least partly conical inner surface (31) on which a complementary outer surface of a coupling body (32) lies in fitting manner, that the bush body (30) and the coupling body (32) are fixed in mutually releasable manner by means of a locking pin (33) and that the coupling body (32) is firmly connected to a truss (13).
Truss construction as claimed in claim 8, characterized in that the trusses (13) are also provided on their outer end with coupling members (30) in the form of a hollow bush body (30) open on at least one side with an at least partly conical inner surface (31) on which a complementary outer surface of a coupling body (32) lies in fitting manner, that the bush body (30) and the coupling body (32) are connected in mutually releasable yet firm manner by means of a locking pin (33).
Truss construction as claimed in one or more of the foregoing claims, characterized in that the connecting means (25) comprise bores (25) in which an internal thread is arranged to close-fittingly receive therein an external thread of a threaded end extending from a coupling element (26).
Truss construction as claimed in one or more of the foregoing claims, characterized in that a fastening means (29) for hoisting means is arranged on at least one of the sides of the basic element (21).
Truss construction comprising a first truss and at least one further truss, wherein the trusses are fixed to each other via a coupling part, wherein the coupling part comprises a basic element (21) having on a first side connecting means (36) for a manually releasable connection to a first coupling element (54A-D) and on at least one further side connecting means (36) for a manually releasable connection to a further coupling element (54A-D), wherein each coupling element (54A-D) comprises on a side remote from the basic element (21) coupling members (30,32) for a releasable connection to a truss, wherein the first truss is connected to the basic element (21) via the first coupling element (54A-D) and wherein the at least one further truss is connected to the basic element (21) via the at least one further coupling element (54A-D), characterized in that the basic element (21) comprises a number of tube parts (51) which form the sides of an imaginary pyramid and which are mutually coupled at corner points hereof via a connecting piece (52), that the connecting pieces (52) comprise the connecting means (36), that the pyramid has a square base (53), and that there is arranged at least practically halfway along at least one of the sides of the base (53) a first further connecting piece (55) which, at least in projection, forms a triangle with diametrically opposite connecting pieces (52) in the base.
Truss construction as claimed in claim 12, characterized in that in a direction substantially transversely of the base (53) of the pyramid, a second further connecting piece (56) is connected to the first further connecting piece (55) and that the second further connecting piece (56) is arranged at least practically at the same distance from the base (53) as the connecting piece (52) which forms a vertex of the pyramid, and which, at least in projection, forms a triangle with two diametrically opposite connecting pieces (52) in the base (53) of the pyramid.