NO332216B1 - System, method and apparatus for producing a supporting framework or stave - Google Patents

Abstract

SUMMARY OF THE INVENTION The present invention relates to a system, a method and a device for the manufacture of a truss or frame (5) of interconnected rod elements (4) and any connecting elements (1) between them arranged in the region of the connecting points, where the rod elements (4) consist of at least one segment of a high-growth plant material and the connecting elements (1) consist of a solid, regenerative material. According to the invention, the ends of the rod elements (4) and / or the connecting elements (1) are machined so that they at least exhibit surfaces which at least extend along well-defined geometric bodies, so that in the region of the connection between a rod element (4) and a connecting element (1) or a further rod element (4) on each of the two bodies (4; 1) is provided with a surface (11; 76) extending at least along a sheath surface of a cylinder, cone, a prism. or a pyramid, as well as a surface (II; 75) extending at least along the casing surface of a hollow cylinder, hollow cone, hollow prism and / or auxiliary pyramid, which may be joined according to the plug principle with adjacent surfaces. The tool useful for this application comprises at least one abrasive device, in particular a tool (56) designed for machining at least one connecting element (1) and / or the ends (73) of rod elements (4) to be connected thereto.

Description

The invention relates to a system, a method and a device for the production of rod elements which are connected or connectable to each other to form a truss or framework, and connection elements which are arranged or can be arranged between the rod elements in the area of all the connection points where two or more rod elements whose longitudinal axes do not run coaxially with each other meet, where the rod elements consist of at least one material of high-growing plants, the connecting elements consist of a solid, regenerative material and at least one end of a rod element, a connecting element to be connected and/or the end of a further rod element to be connected is processed in such a way that they at least zonally exhibit surfaces that run along well-defined geometric bodies. For this purpose, the cross-section of the drill holes in the connecting elements must be very oversized because the cross-section of the bamboo tube will be able to vary within wide limits. This therefore leads to a large need for spray adhesive or molding compound. Since, moreover, due to the large volume of spray, adhesive or molding compound, in addition to the adhesion properties of this material, its mechanical properties are also of great importance for the stability of the truss, a high-quality material is required, so that the total costs are increased significantly. In addition, the assembly is very labor-intensive.

From the disadvantages of the described state of the art, the problem that leads to the invention arises to improve a system of the initially mentioned type for producing a truss in such a way that it results in an optimal ratio between effort and result, i.e. that the costs and/or or the work effort to produce a construction will be able to be reduced without its stability becoming worse. At the same time, the rod elements' sustainability and compatibility as well as low cost enable the construction of large structures such as houses and bridges.

With a system of this type, the solution to this problem is achieved by the characteristic features according to claim 1. Preferred systems will be able to be derived from the non-independent claims. The invention also includes a method and a device as stated in claims 6 and 9.

Tall plants are reinforced with fibers that run in the longitudinal direction and therefore exhibit optimal stability when it comes to (tensile) stresses in the longitudinal direction. On the other hand, since constructions produced by the system according to the invention are divided into trusses with nodes and straight connections between them, it is not required that the rod elements have a high bending strength. Therefore, it will be possible to dispense with fibers which run obliquely or transversely in relation to the long axis of the rod element, and especially those which run in radial directions or crosswise in relation to each other. By using regenerative raw materials for the rod elements, it will be possible to save expensive chemicals, which also originate from fossils and are therefore limited available materials. Furthermore, regenerative raw materials are built up by photosynthesis, whereby carbon, which is required for a quantity of organic compounds, is extracted from the air's carbon dioxide, which is why its climate-changing effect as a greenhouse gas is reduced. Biological materials will also be easier to get rid of without burdening the environment.

For the system according to the invention, it is very important that both elements at the connection between a rod element and a connection element or a further rod element at least in areas have a surface that runs along the surface formed by a cylinder, cone, prism or pyramid, as well as at least in areas exhibit a surface which runs along respectively a hollow cylinder, hollow cone, a hollow prism and/or a hollow pyramid. On the one hand, these are bodies that can be produced by relatively simple processes such as milling or turning. On the other hand, this enables a connection by plugging with closely adjacent surfaces, which is suitable for locking by clamping and/or gluing. By using a press fit, an even higher strength of the connection can be achieved. By e.g. a rod element is a convex hollow element always present on the outside of a concave fixed element (core), so that two standardized surfaces that lie within each other can easily be created by treating the inside and outside. If two surfaces which are approximately complementary are formed at the connecting element, whereby the convex hollow element is placed outside the concave solid element (the core), then the potential adhesive surface and thus the strength of the connection can be roughly doubled. Furthermore, a rod element that is introduced into a recess is completely covered on its outside and will therefore always be firmly pressed to both adhesive surfaces even with different expansion, such as e.g. can be caused by moisture (swelling).

The invention recommends that the two different geometric shapes along which the surface of a body runs are arranged concentrically in relation to each other. Such a device of special homogeneity can be produced in a very simple way and comes, e.g. closest to the natural geometry of a bamboo tube.

If the two different, but somehow symmetrical shapes along which the surface of a body runs, exhibit constant mutual distances, the result is an isotropic structure which enables an arbitrary rotation of the bamboo tube about its axis and therefore offers a further degree of freedom for to enable a fine adjustment at difficult truss junctions.

The joining of a rod element with a connecting element can be designed as a plug connection to relieve additional locking devices by means of a

strong positive join. Clamp connections as well as adhesive connections, e.g. using wood glue, can be used as a locking device. In addition to the positive locking of the plug connection, threaded sleeves and/or screw bolts can be arranged to (partially) transmit forces acting in the longitudinal direction of the plug connection

via a screw connection.

In order to clamp a rod element to a connecting element or to a further rod element, a core which is integrated there and intended for engagement with the rod element can be spread and thereby pressed from the inside towards the inside of the rod element. To spread the core, an element that expands continuously, e.g. shaped like a cone or a truncated pyramid, is pushed or pulled into an inner, preferably centered recess in the spreadable core. Thereby, this element transforms an activating force in the axial direction into a radial deformation of the spreadable core. For this purpose, the connecting element can be provided with a cut-out which extends through the core and into which the shaft of a screw, a threaded bolt or the like can be inserted. The latter directs the axial force from a self-locking rotation in relation to another threaded element, which thereby absorbs the counterforce that occurs when an element with a widening cross-section is pulled into the core.

If a connecting element is in the form of a ring, not only rod elements directed towards this connecting element from arbitrary directions within the base plane of the ring can be adapted and securely anchored. It is also possible to extend each of the recesses for fitting a screw-like spreading element as far as the inside of the ring to be able to arrange a threaded element or other clamping element there, which in turn will be easily operable for locking after of the relevant connections are provided. However, the longitudinal axes of all connected rod elements are preferably directed towards a central point of the connecting element so that no torque which could lead to bending stresses in the rod elements occurs in the framework.

Preferably, the bypass element has a disk-shaped shape, e.g. with a circular, triangular, square or hexagonal base surface. Such a connecting element is particularly suitable for flat trusses, as all connections lie in one plane there. If e.g. a crossbar is to be made for a parallel flat truss, it is advisable to design these connections so that they do not run perpendicular to a flat truss. The inclined anchoring structures required for this will be able to be adapted in several different places on a disc-shaped connecting element, but also on a further connecting element which is attached to it. The thickness of such a disk-shaped connecting element must be greater than the maximum diameter of a rod element, so that its end area is completely encapsulated in the connecting element. If thereby e.g. if bamboo is used for the rod elements, it will thus be possible to achieve that the more delicate inner side of a bamboo tube will not be accessible from the outside.

Instead of the described embodiment of the transition element which is made in one piece, it can also be made in two pieces, so that the two halves, which are initially separated from each other, can be placed around a continuous rod element to enclose it completely after the connection, and for example anchoring a further rod element at a place in a truss where there was previously no node. In this way, such a "half" connecting element can also be attached to the stem of a rod element, for example by means of glue. For this purpose, the connecting element comprises a concave connecting surface which partially encloses the rod element in question. To produce such a glued joint, the relevant area of the stem of the rod element should also be machined on the outside, especially milled to a round shape.

Within the framework of the invention, a rod element can be inserted between two connecting elements or between two other rod elements to extend these in a coaxial direction. While both ends of the rod element in the first case must have the same plug connection construction (e.g. ring plug - ring plug), in the latter case it will pay to arrange in principle mutually complementary plug connection constructions (e.g. ring plug - ring groove) in both ends, so that standardized rod elements that fit together are always obtained.

For the rod elements, the invention further proposes the use of trunks, stems or stalks of tall-growing plants which can easily be processed into elongated elements for trusses. Besides the dicotyledons which are widespread in Europe, especially deciduous and coniferous trees, where straight, thin trunks with a diameter of up to approx. 10 or 15 cm (so-called soft wood) is well suited, plants of monocotyledons (palms, grass etc.) can also be used, as the vascular bundles in these are so irregularly distributed that no medullary rays appear. The result is that not all the fibers are arranged next to each other in a regular pattern. As all the fibers run parallel to each other, the device in e.g. isogonal rows or even only in a single ring lead to unreinforced binder surfaces along which a separation, i.e. crack formation, would be significantly facilitated. Such fiber-free central or core rays must therefore be avoided if possible. Furthermore, an increase in the fiber density towards the outer circumference of the rod element should be sought, where naturally the greatest forces will occur in the event of a bending stress that nevertheless occurs. According to this inventive idea, one finds among the grass family the so-called giant grass or bamboo plants which further bring the advantage of an accumulation of vascular bundles or fibers on the outer circumference and thus have great bending strength despite the fact that the fibers run in the longitudinal direction. Indeed, the trunk or stalk of bamboo plants is divided into nodes (nodal surfaces) and segments between the nodes (tubular areas) in the longitudinal direction. In the case of live bamboo, the cross-linking of the fibers should increase elasticity; in the case of harvested and dried bamboo, these can of course also cause tension, which is why they will have to be drilled out. An excessive influence on the stability of such a bam-bus pipe cannot therefore be feared. As the segments between the junctions have an extremely homogeneous structure and the junctions as growth centers only form thin surfaces, the properties of the pipes are dominated by the properties of the segments, i.e. the segments between the junctions. Only the tensile strength is reduced at the nodes, but not the compressive, shear and bending strength, so that the stability of such a truss which is predominantly exposed to pressure will not suffer.

In the course of a year, many bamboo plants grow to a height of up to 30 metres, while in the following years, lignification takes place exclusively without further growth. In tall bamboo plants, the trunk diameter is between 5 and 20 cm, and the thickness of the tube wall is between 0.5 and 8.0 cm. Bamboo has, with the exception of the knots that are regularly encountered, no defects, as these can be found e.g. in the form of branch systems (so-called branch holes) which further affect the stability there, in the case of dicotyledons. Due to its high mechanical stability, bamboo pipes can absorb large compressive and tensile forces in the longitudinal direction, which in the area of the segments between the nodes will be comparable to those of steel. The bending load is limited first by a deflection at strong bending forces for the formation of angles. Although bamboo plants grow somewhat straighter than most types of wood, there are almost always curvatures that cannot be overlooked, such as significant irregularities in the pipe cross-section. For this reason, bamboo tubes have for a long time always been connected with cords, fibers or the like, which, on the other hand, would be completely inadequate for the production of a truss or framework, as no forces would then be able to be transferred in the longitudinal direction of a used bamboo tube .

As the outer side of the stem is covered with a hard, water-repellent and extremely resistant layer containing silicates while the inner side is provided with a waxy coating, these areas are non-wetting for many adhesive materials and will therefore damage the durability of an adhesive connection. As these layers are also relatively smooth, the frictional connection that can be achieved is relatively poor, so that the invention recommends removing these layers, but only in an area that is preferably not exposed to the atmosphere, so that no water can penetrate into areas that are not is protected against moisture.

The shape of the rod elements themselves can be diverse. In accordance with the chosen material, a rod-shaped structure, i.e. with a massive core, as occurs in e.g. hardwood or softwood, is preferred, or a tubular structure, which is offered by the use of bamboo tubes. The hole drilling of solid wood rods also has the advantage of uniform drying over the cross-section with consequent uniform and therefore crack-free shrinkage.

A further point of view is that bamboo reed is a biological material that "works" under the influence of its environmental conditions and therefore, e.g. when using an intrinsically rigid end piece of e.g. metal or plastic, in the course of time will have a tendency to crack. This in turn would have fatal consequences because the water-repellent surface had thus been broken, after which water could penetrate and trigger rotting or the like. For this reason, according to the invention, it is preferred to use connecting elements of a comparable biological material, such as e.g. dicotyledons, especially deciduous or coniferous. These show a similar reaction to changed environmental conditions as monocotyledons and will be able to "co-operate" with them, so to speak, so that the internal material stresses remain relatively small. To ensure this, any intermediate piece between the monocotyledon tubes and the connecting elements must be avoided if possible. The invention therefore provides a direct connection, either as a plug, clamp and/or adhesive connection. Such an industrially applicable bonding technique with acceptable costs is, on the other hand, still conditional on standardized contact surfaces, which a naturally growing giant grass will not be able to offer. This is remedied by the invention as the irregular ends of a bamboo tube to be used are first processed so that surfaces are created which run along well-defined geometric bodies. This work step can be integrated with the above-described removal of the surface layers in the area of the connection points.

In order to achieve the most optimal compatibility between a connecting element and a rod element, this can, as already mentioned above, consist of wood. Wood and bamboo are both organic materials, but have fundamental differences. Therefore, if necessary, plate materials of glued together layers of bamboo material can also be used instead, so that material properties are achieved that are identical to those of the bamboo pipes.

When a connecting element e.g. is air-tightly connected with a tubular rod element of e.g. bamboo tubes by means of a sealing gluing, and exhibiting internal interconnected channels leading to the cavities of the connected tubular rod element, where the knots, in the case of bamboo tubes, are pierced, then a closed cavity is created with an intentionally influenceable secondary climate within a subject or framework prepared in this way. This secondary climate can be influenced in many ways in order to be able to manage and/or monitor the properties of the framework, or to keep potential disruptive effects of pest attacks from within, fire or the like away from the framework. Hereby, it has proven expedient when at least one connecting element and/or tubular rod element has a connection via which gas, foam and/or liquids can be supplied to the system's cavity, e.g. moist or dry air, in order to be able to keep the bamboo flexible with the help of a controlled climate, toxins such as hot air, cold air or compressed air as a means of pest control, or extinguishing agents such as e.g. nitrogen, foam or water or the like.

In order to solve this task, the manufacturing method excels in the characterizing part of the side-ordered process requirement. Further preferred features of the method according to the invention are specified in this subclaim.

The properties of standardized surface areas of naturally growing materials, e.g. wood or bamboo tubes, which are primarily unfilled, are indispensable for their processing within the framework of a truss so that the individual parts will fit together exactly and will be able to be plugged together in the desired way. Furthermore, it is very advantageous if the alignment of the standardized end areas in relation to each other is also predetermined precisely. Particularly favorable conditions are achieved when the end areas are processed so that the geometric bodies that define their surfaces at least zonally exhibit an axis of symmetry that can be aligned in a mutual relationship, e.g. in a common line of sight. Only then will it be possible to observe the pre-determined angle of inclination of the rod elements exactly in order to unite these with pre-determined truss nodes. These prerequisites enable the true-to-pattern production of trusses that are pre-calculated in terms of their statics, which is of greater importance the larger the construction. On the other hand, thereby e.g. the possibility of using (wooden) rods and/or (bamboo) tubes of variable length not affected, as the processing of the ends will then be able to be carried out on the construction site after a (possibly tubular) rod element has been cut to the desired length. Furthermore, at least one outer surface must be formed on a connecting element which enables plugging with a outer surface at the end of a rod element. The diameter of this mantle surface and thus the selection of the tool required for its formation is possibly based on the classification of the relevant hollow stick or bamboo stirrer. As this is usually only determined immediately before the installation of the rod element in question, the appropriate connection structure is first incorporated into the connection element in question at the point of use.

Preferably, the bodies and/or surfaces of the parts to be connected to each other are processed, in particular chip-separating. This technique is equally suitable for the preferred materials bamboo and wood. The tools required for this are easy to handle and will therefore be easy to take to a construction site. Thus, the processing and post-processing of already constructed connecting elements, e.g. with a hand drill or milling machine possible. Rod elements such as wooden rods or bamboo tubes are processed before installation, but after suitable cutting. A clamping device is required for this.

Because in the case of connection elements (but also in the case of rod elements to be added directly to) which are exposed to (releasable) clamping connections to enable a radial resilient movement of (areas) of a mantle surface of a connecting structure, in particular a core, in areas adjacent to slits are placed on this mantle surface which preferably run parallel to the longitudinal axis of the plug connection in question. These slots will also already be able to be arranged in a factory. As a part of the connecting element must still be removed during the (later) incorporation of an annular recess as a connection structure, it is not necessary to have an exact radial extent of the slot, as this only has to be dimensioned so that it reaches the relevant mantle surface.

Before the assembly of a rod element, a spreader must first be inserted into a bore that runs parallel or coaxial with the longitudinal axis of such a clamp connection, which spreader can be used after joining to give (areas of) the relevant mantle surface a (radial) pressure in the direction of a mantle surface at the end of a rod element to be connected.

The rod elements are then plugged together with the appropriate connecting or rod elements and clamped or glued to each other. Necessarily, these work steps proceed partly in parallel, as almost every node connection element on the one hand rests against rod elements and on the other hand carries further rod elements, so that some connections occur earlier and others later.

Along the longitudinal edges of a beam or framework, connection elements are used as end pieces which will be able to be connected to a foundation, a cover, a roof or the like. With these, there is a preferably flat base surface with an anchoring option, e.g. one or more holes for piercing fixing screws.

A cladding or the like can be attached to the connecting elements of the frame and framework to achieve a wall-like appearance, as e.g. required when building a house. As a corresponding anchoring occurs exclusively to the connecting elements and, on the other hand, not to the rod elements themselves, the latter remains undamaged and thus preserves its outer surface's possible water-repellent properties, and a cavity encompassed by the truss remains tight. If, however, cladding of low strength is to be attached to the framework, e.g. plasterboard panels, then either the distances between the truss nodes can be reduced, or a substrate is first attached to these, to which the sheet cladding in question will thus be able to be attached at short distances.

For the end regions of a tubular rod element, especially a bamboo tube, the inner and/or the outer mantle surface can be machined. For small trusses, processing a single cladding surface, e.g. the outer one will be sufficient, while in the case of heavily loaded trusses, both sheathing surfaces at each end of a bamboo tube will have to be processed in order to, by increasing the potential adhesive surface and with the help of a further shape adjustment in both radial directions (inside and outside), optimize the stability of each individual compound.

Thereby, account must be taken of the fact that the radius fluctuates in the case of wood or bamboo pipes, and in the case of bamboo pipes or hollow-drilled wood also the wall thickness. E.g. decreases the outer diameter of a 30 m high bamboo tube, but especially also the wall thickness, from bottom to top. Due to this reduction of the wall thickness, mostly only the bottom 10 m of a bamboo tube can be used for the purpose according to the invention. If this section is terminated in e.g. individual parts with a length of 1.5 m, each short bamboo tube will still have a different wall thickness and possibly also a different outer diameter. From case to case, these deviations will be so significant that the outer diameter per meter of a cut piece of bamboo pipe will be smaller than the inner diameter of another piece of bamboo pipe. Joint processing with identical tools is therefore not considered. For this purpose, the invention provides for providing different classes for (the ends of) bamboo pipe pieces in terms of wall thickness and/or with regard to inner and outer diameter or circumference. Thereby, both the (minimum) inner diameter and the maximum outer diameter can be easily determined with the help of a gauge. Such teachers can have the shape of a cylinder or a flat rectangle (for the inside), or the shape of a hollow cylinder or a fork (for the outside). Naturally, these sizes can also be measured differently. Each bamboo tube (end) is thus divided into a more or less fine classification system, and the selection of the various tools for processing is determined accordingly. In addition, the invention recommends that the sheath surface(s) of a bamboo pipe end be processed so that the wall thickness of the bamboo pipe is equal to or less than a wall thickness that is predetermined on the basis of the classification system).

Before the installation of a bamboo tube, any existing knot surfaces must be pierced or made through in some other way in order to provide a cavity in the finished truss. In order to achieve a cavity connection for a bamboo pipe connected to a connecting element, bores must be provided which open into the surface areas of the connecting element and which are covered by the outside of a built-up bamboo pipe and meet inside the connecting element. On the other hand, the overall cavity in a truss can, if necessary, be divided into several sections, which will thus be able to be influenced independently of each other by means of the targeted application of special connection elements without such continuous channels. The purpose of the drilling is also to ensure uniform shrinkage of the bamboo tube during drying after harvesting and thereby avoid tension in the bamboo and thus cracks.

On the other hand, the diameter of internal channels connecting the cavities is independent of the diameter of a wooden or bamboo pipe to be connected. If it is known on the basis of the finished construction foundations, with which bending angle tubular rod elements, e.g. bamboo pipe, hits a connecting element, the necessary transit channels will therefore be able to be produced already during the production of the connecting elements and thus be produced before these are built in. For this purpose, the blank for the connecting body will be able to be accurately clamped, so that the bores provided from different sides really meet in the middle. Preferably, a possible mobile processing center is used with guides of aluminum profiles and multi-axis servo drive devices that work according to the specifications of a pattern software. Such cavity connection bores will thus be used as tool guides on a building site when forming the relevant mantle surface(s) for connecting each individual rod element. In the case of connection elements without cavity connection channels, corresponding bores intended for tool guidance can also be arranged during production.

As far as at least in one tubular rod element, especially bamboo tube, and/or preferably in at least one connecting element, an entrance to the cavity in the tubular rod elements and connecting elements is arranged, different media can be led into this cavity if necessary. In order to thereby be able to leave a medium, e.g. air, which may already be present in the cavity could escape, it is recommended that at least two such inlet connections are always arranged to an inherently closed cavity. These must be arranged at remote points to provide defined flow conditions. Thereby, it has proven appropriate to arrange one such entrance at the deepest point and possibly a second entrance at the highest point of a truss section, so that on the one hand liquids and on the other hand also gases will always be able to be completely removed from the cavity again .

A device for carrying out the method according to the invention is distinguished by the characteristic features according to the independent device requirement.

The use of such a device simplifies the production of a truss according to the invention, as a time-consuming, manual single treatment or later processing of the various junctions of the truss will thereby be omitted because mutually compatible surface areas are formed. Since a processing device according to the invention is designed as an abrasion tool, in particular as a cutting tool, this will, thanks to the small space requirement, be mobile and thus transported to a construction site without problems.

A device for processing the ends of a rod element is characterized by a device for clamping a rod element so that both of its ends are aligned as concentrically as possible with a longitudinal axis of the processing device. Thereby, the actual processing tools for a rod element to be processed always occupy one and the same predetermined position, so that they can be adjusted in a defined manner in relation to a machine chassis. Underneath, there is usually a holding device and/or fastening device for each processing tool at each end of the clamping device. One such can e.g. be designed as a slide, which with the help of a guide can be guided along the longitudinal axis of the processing device in the forward direction, and on the other hand carries the actual holding device and/or fastening device for the processing tool and/or its drive motor.

A cutting tool, e.g.

in the form of a milling head which is designed for simultaneous processing of both the inner and the outer mantle surface of the ends of a rod element, especially a bamboo tube and for this purpose is provided with two separate processing, especially cutting parts. The actual cutting parts can be releasably and thus replaceably fixed on a tool base body or can be adjusted in relation to this, whereby an adaptation to differently classified bamboo tube ends will eventually be possible.

A preferred device for processing a connecting element is characterized by a tool that rotates about an axis and is provided with at least one cutting part for forming a rotationally symmetrical recess with a defined cross-section. The tool can suitably be designed for clamping in a hand drill or similar, thereby also being able to be used on knot connection elements that have already been built into a truss. In another embodiment, the rod element, in particular the bamboo tube, can rotate and the tool can be fixed so that it only performs forward pushing and feeding movements consistent with the function of a classic lathe.

According to a further aspect of the invention, the cutting part is arranged in a peripheral mantle area of the tool's base body which is arranged so that it surrounds a central guide device, e.g. a peg that projects forward. With the help of such a guide device, the tool can be centered on a pre-drilled, e.g. cylindrical guide recess to thereby ensure that the rod element to be inserted assumes a precisely predetermined bending angle and thereby with its overlying end will be able to be inserted into the knot connection element located there.

Finally, it is in accordance with the teachings of the invention that the central guide device is designed as a drill, so that the guide bore and the insertion recess can be produced in one work step. This variant is above all intended for truss nodes that have not been calculated in advance and in whose connecting elements no pilot holes can be incorporated in the factory. In these cases, the fitter can decide the direction of an insertion structure that will accommodate a rod element; he must therefore first of all work carefully to, on the one hand, possibly hit a central cavity channel and, on the other hand, to determine the exact orientation of the rod element to be inserted.

Further features, details, advantages and effects on the basis of the invention will appear from the following description of preferred embodiments of the invention with reference to the attached drawings, where

fig. 1 is a perspective view of a first connection element for a truss system according to the invention,

fig. 2 shows a modified embodiment of a connecting element in a figure corresponding to fig. 1,

fig. 3 shows a section of two connecting elements according to fig. 2 which are attached to each other,

fig. 4 shows in perspective a modification of the connecting element in fig. 2,

fig. 5 is an exploded view of a pluggable connection with the connection element of fig. 4 as well as a partially cut and broken bamboo tube,

fig. 6 shows the composition in fig. 5 after mounting the connection,

fig. 7 shows a deviating configuration of the invention,

fig. 8 shows a perspective view of a connecting element such as e.g. is applicable as a basic element,

fig. 9 is a side view of a flat truss that is built using the system according to the present invention,

fig. 10 shows a connecting element of the truss in fig. 9 in interrupted and partially sectioned view, as well as a tool arranged at a side surface to form the cavity for receiving a bamboo tube,

fig. 11 is a longitudinal section of the tool in fig. 10,

fig. 12 is an interrupted side view of a device for clamping and processing the ends of a bamboo tube,

fig. 13 is a perspective view of a clamping device of the device of fig. 12,

fig. 14 is a front view in the direction of the arrow XIV of the tool of FIG. 12, and fig. 15 is a section of two coaxially connected rod elements.

The perspective view of a connecting element 1 in fig. 1 is intended to illustrate the main principle of the invention. An arbitrarily or randomly shaped connecting element 1 is provided on its surface 2 with one or more three-dimensional structures 3, each of which is intended for the connection of a bamboo pipe 4. When mounting several bamboo pipes 4 to such a connecting element, this becomes a hub in a fag- or framework 5.

The connecting element 1 in fig. 1 has the basic shape of a rectangular parallelepiped with four equal side faces 6 and both square top and bottom sides 7. The epiped-shaped connecting element 1 consists of many layers of plywood 8 which are each glued to each other with intersecting fiber direction. As these glued layers of plywood 8 run parallel to the square top and bottom sides 7, the connecting element 1 has high tensile strength in directions that run parallel to these planes.

A structure 3 for connecting one bamboo pipe 4 is arranged at all six surfaces 6, 7 of the connecting element 1, so that six bamboo pipes 4 will be able to be brought together at such a junction of the truss, two of which are aligned with each other and stand perpendicular to plane for the other four bamboo tubes 4. Thus it becomes possible to produce a three-dimensional truss.

As further shown in fig. 1, each structure 3 for mounting a bamboo tube 4 has the approximate shape of an annular recess 9 with two delimiting surfaces 10, 11 in the form of the side surfaces of cylinders which are mutually concentric. The outer diameter of these recesses 9 corresponds approximately to the outer diameter of the bamboo tube 4 in question and the constant distance between the boundary surfaces 10, 11, and the shape of the side surfaces of the cylinders corresponds approximately to the standardized maximum thickness of the end area of a bamboo tube 4 that will be able to be introduced in this recess.

In the embodiment according to fig. 1, the ends of the bamboo tube 4 are glued into the annular recesses in the connecting element 1 so that a firm and insoluble connection is achieved. As further shown in fig. 1, there remains inside each annular recess 9 a cylindrical core 12 which is bonded to the inside of the bamboo tube 4 and thus additionally fixes and stabilizes this bamboo tube 4. Since wood exhibits comparable temperature coefficients and swelling conditions due to moisture as bamboo, preventing thus the formation of cracks effectively.

Furthermore, each cylindrical core 12 is pierced by a bore 13 in the longitudinal direction. All these bores 13 meet in the connecting element 1 and thus form a system of connecting channels between the cavities in all the connected bamboo tubes 4.

If, as the invention provides, all the membranes of the bamboo tubes 4 are pierced, these cavities are connected to the connection elements 1 found along the bamboo tubes 4, and in this way also to all other cavities of trusses or frameworks 5 produced in this way. Then on the other since the cavities in the bamboo tubes 4 are hermetically sealed with the help of their airtight outer surfaces, an expedient influenceable secondary climate is achieved in the connected cavities of a truss or framework 5 according to the present invention.

E.g. poisons, hot or cold air or other pest control agents will be directed through this cavity to avoid pest attacks on such a structure or framework 5 without the pest control agent used thereby ever coming into contact with the surroundings. The system according to the invention entails the advantage that the additives, regardless of their nature, in the smallest quantities are always highly effective without ever affecting the surroundings. For a similar purpose, it will be possible to provide strong temporary pressure variations.

Furthermore, this cavity can be filled with non-combustible gas, e.g. nitrogen, under overpressure, so that in the event of a fire, nitrogen is released to a significant extent at the scene of the fire to suffocate the fire. At the same time, the sudden drop in pressure caused by this can be measured and from this it can be concluded that there is a fire, and when water is introduced, precautions are taken against further spread of the fire. As soon as the fire is extinguished, the water can be diverted away again, and by connecting hot air, the 5 internal cavities of the frame or framework will be dried again.

The connecting element 14 in fig. 2 has a cube-shaped design and is as far as

modified as only on the upper and lower side 15 is there arranged a structure 3 for connecting bamboo pipes 4, while on the circumferential sides 16 only central bores 17 are arranged through the connecting element 14. This connecting element 14 also consists of mutually glued plywood layers 18 which run vertically on the top and bottom 15.

Above all, the connecting element 14 serves to extend the bamboo tube 4. In order to thereby also realize framework knots, two or more such connecting elements 14 are attached to each other as shown in fig. 3. For this purpose, the connecting elements are placed on top of each other in the desired orientation, so that always one of their bores 17 is flush with each other. A screw or a threaded bolt 19 is thus inserted through this line of bores, which is provided on both sides with a counter nut 20, so that the connecting elements 14 are attached to each other.

Now the bamboo tube 4 will be able to be inserted and glued in the desired way in the available connection structures 3. This arrangement involves the further special feature that with such a framework knot it is possible to carry out a turning movement for adaptation to framework constructions which proceed crookedly in relation to each other.

At the connecting element 1, the bamboo tubes 4 glued to the structure 3 on the top and bottom are only glued together with part of the plywood layers 8, so that e.g. the relevant core 12 and thus the entire bamboo tube 4 will be able to be torn out by the effect of high tensile forces. This can be prevented as a connecting element 14, e.g. with a pierced threaded bolt 19 with counter nut. Thereby, the connecting elements 14 can be arranged so that their layer-glued plywood sheets 8 run vertically on the upper and lower side 7 of the connecting element 1 and almost all of them are thereby glued together with the bamboo rod 4 in question.

The connecting element 21 in fig. 4 has the same cube-shaped design as the connecting element 14. As there, the three-dimensional structure 22 for connecting a bamboo tube 4 comprises an annular recess 9 with two mutually concentric, cylinder-mantle-shaped limiting surfaces 10, 11. The core 23 which remains within this recess is provided with a continuous central bore 13. In contrast to the connecting element 14, however, the core 23 is provided with two incisions 24 which cross each other along the longitudinal axis of the bore 13 and which reach approximately to the bottom of the core 23 or the annular recess 9, so that the remaining core quarter 25 will be able to spring outwards to a limited extent.

The central bore 13 in the core 23 has a cone-shaped recess 26 in which the head of a countersunk screw 27 inserted into the bore can engage with machine threads 28. On these threads 28, the outer side 7 of the connecting element 21 which lies opposite the connecting element 22 is screwed on a threaded element 29. After insertion 30 of a bamboo tube 4 in the annular recess 9, this threaded member 29 is pulled tight. Thereby, the screw head 31 presses itself ever deeper into the cone-shaped recess 26 and thereby spreads the core fourth part 25 outwards. This again presses with its outer side 11 against the inner side 32 of the sheath 33 of a bamboo tube 4 and thereby clamps this firmly. Thus, gluing the bamboo tube 4 with this type of connection 21 is not necessary and the connection will always be able to be detached without damage. Instead of a countersunk head screw 27, a conical bolt or the like could also be used.

A further connecting element 34 is shown in fig. 7. This has the form of a circular ring 35 with a rectangular or square cross-section. On the outer side 36 of this ring 35 there are six three-dimensional structures 22 which are equally spaced around the circumference for connection to each of the bamboo tubes 4. The three-dimensional connection structures 22 are, in terms of topology and function, identical to the relevant structures 22 of the connecting element 21, so that a cross-section through the ring 35 at one connection point 22 largely corresponds to fig. 6, with the exception of the fact that here the transverse bore 17 is missing as well as a connecting structure on the inside of the ring 37.

The ring 35 offers the advantage that an almost arbitrary number of connection points, from just one to up to six or possibly even more, depending on need, can be arranged, whereby all connections 22 can be made detachable.

With such a ring, e.g. planar trusses or frameworks 5 could be produced, as shown in fig. 9. Connection elements 38 of the type shown in fig. thus serve as the base element. 8. These each consist of a parallelepiped 39 whose length is approximately twice the height and width. They are provided with a central, continuous vertical bore 40 for screwing to a foundation 41 etc. In the area of their upper short edges 42, a three-dimensional structure 43 for connecting a bamboo tube 4 is arranged at each.

In terms of its function, the structure 43 corresponds to the structure 3 of the embodiments 1 and 14, where a bamboo tube is not fixed by clamping, but

when gluing. Admittedly, the annular recess 44 and the one with this concentric bore 45 are not arranged vertically on a surface of the connecting element 38, but at an angle of 30° upwards, diverging outwardly from the vertical bore 40. Moreover, the structure 43 overlaps the upper short edge 42, so that in particular the front side of the connection structure 43's core 46 is formed by two vertically standing partial surfaces 47, 48, each of which constitutes a remaining part of the original

surfaces 49, 50 of the connecting element 38. However, this fact does not impair the function of the three-dimensional structure 43 as a connection and attachment point for a bamboo tube 4.

As can be seen from fig. 9, for the production of a truss or framework 5, a number of connecting elements 38 are first screwed or otherwise attached to a foundation 41. After the connecting structures 43 have been coated with glue, ends of bamboo tubes 4 are inserted into them, which all diverge 60° from each other upwards. Two bamboo tubes 4 are connected to each other at their adjacent upper ends 51 via a knot element 52.

The one node of the frame element 5 which forms the connecting element 52 has a similar basic shape to the connecting element 1, but in contrast to this, it has a base surface that is equal to a regular hexagon with a constant thickness that is larger than the maximum diameter of a bamboo pipe 4. Like all other connecting elements 1, 14, 21, 34, 38, this also consists of intersecting plywood layers which are glued together and whose surfaces run parallel to the hexagonal base form sides 53. The circumference of such a connecting element 52 is similarly composed of six equal-sized rectangles .

Before the glue hardens, adjacent knot elements 52 are connected to each other by means of each horizontally running bamboo tube 4, which is glued in at the same time. This creates a first layer of the truss and framework 5. As soon as this has in and of itself been stiffened by curing the glue, which when using wood glue takes about a quarter of an hour, according to the same principle, a further truss layer can be put on top of this, as as indicated in fig. 9. The finished truss 5 is composed of only equal cells with the shape of an equilateral triangle and thereby obtains maximum stability. If necessary, another, also three-dimensional structure can of course be chosen for a subject or framework 5, e.g. in the form of two parallel flat trusses or similar that are connected to each other. Preferably, the bamboo tubes 4 always have a length of only approx. 1 - 2 m, so that a buckling effect cannot occur in the event of excessive bending stress on an excessively long bamboo pipe 4.

The knot elements 52, like all other connecting elements 1, 14, 21, 34, 38, can be completed individually on a construction site on site. For this purpose, first the base body 55 with the desired circumferential shape is sawn out of a plate, preferably of wood, especially of layer-glued plywood, which may possibly take place in a factory or at a sawmill. In this base body 55, the relevant necessary connection structures 3, 22, 43 are then incorporated on site, possibly even in an already built-in state. A processing tool 56, as shown in fig. 10 and 11.

As for the machining tool 56, it is a rotary tool head which exhibits a rear facing connection for a drive motor. The connection can e.g. be made as a cylinder extension 58 which is coaxial with the tool's longitudinal axis 57 and which can be inserted into the socket 59 of a hand drill. In the embodiment shown, this cylindrical mounting extension 58 is part of the shaft of a (wooden) drill 60 with which the central recesses 13, 45 in a connection structure 3, 22, 43 are drilled. An approximately bell-shaped tool part 62 is releasably attached to the shaft of this drill 60 by means of a clamping screw 61.

This bell-shaped tool part 62 consists of an approximately annular disc-shaped part 63 and an approximately cylindrical mantle-shaped part 62 which extends forwards from its periphery, and which in the area of its front side carries the actual cutting tool 65 for forming the annular recess 9 of a connection structure 3, 22 , 43. The annular disc-shaped part has an inner diameter which corresponds to the diameter of the drill bit 60 and an outer diameter which roughly corresponds to the outer diameter of a bamboo tube 4. On its back side 66, this part 63 is provided with a shoulder 67 with a narrowed, but still cylindrical cross-section, through which it extends a radial threaded bore for receiving the clamping screw 61. Thus, the annular disc-shaped part 63 will be able to be stuck on the shaft of a drill 60, where it is aligned vertically with the drill's longitudinal axis 57 via a fit almost without clearance, so as to be locked in this position by screwing in the clamping screw 61.

The cylindrical shell-shaped part 64 can either be produced integrally with the disk-shaped part, e.g. cast together with this, or it can e.g. is processed by a tubular part which, as shown in fig. 11, is screwed with the disc-shaped part 63 from the back 66 of this with screws 68 that run parallel to the bore axis 57. In the area of its front side, the cylinder jacket-shaped part 64 is provided with a plurality of roughly rectangular cutouts distributed evenly around the tool circumference, as that an approximately crown-shaped design is provided.

On several cutting surfaces 69 of the cylinder jacket-shaped part 64 running approximately parallel to the longitudinal axis of the tool, a small cutting plate 70 is attached to each, preferably by means of a screw 71 which engages through a central recess in the plate in question. As can be seen from fig. 11, it is up to this cutting plate 70 to cut the annular recess 9 in the body of a connecting element 1, 14, 21, 34, 38 during the turning movement of the processing tool 56, as well as under the influence of a superimposed forward movement 72. Thereby, the drill 60, if the front part is located in front of the cutting plate 70, take over a guiding function.

In other embodiments of the invention, the recess in a connection structure can be delimited by chamfered or completely conical limiting surfaces at its bottom; for the production of such recesses, the cutting tools must have a corresponding geometry, possibly also the cross-section of the cylinder jacket-shaped part 64 must be adapted.

As already stated above, the growth of a bamboo tube 4 is always more or less irregular. Although the annular recess 9 of a connection structure according to the invention is optimally round, thanks to the use of a processing tool 56 which rotates about an axis 57, a bamboo tube 4 will therefore in normal cases not be able to be inserted in a matching manner. Either the bamboo tube does not fit into the recess 9 intended for this at all, or it sits far too tight, or when the recess is dimensioned further, too loose, so that no clamping effect will be achieved, or large amounts of glue are required, which not only drives up costs, but also the working time as a result of increased drying times.

For this reason, the invention provides for processing the ends 73 of the bamboo tube 4 which has been cut to the desired length before the installation in a truss or framework. Thereby, it is necessary to give these a standardized geometry, so that they fit into the recess 9 arranged for this purpose in the relevant connecting element 1, 14. 21, 34, 38. However, this is generally not satisfactory for the construction of a precisely pre-planned framework or framework 5, as the two ends of a cut bamboo tube 4 often do not run coaxially with each other. This in turn would lead to displacements and/or stresses in a truss 5, which generally accumulate during the construction phase, so that a larger construction would become increasingly crooked as the construction progresses. A machine 74 for processing the ends 73 of a bamboo tube 4 therefore has the further task of ensuring that not only the two end areas 73 of a bamboo tube 4 at least zonally exhibit surfaces 75, 76 which run along cylinder jacket surfaces (in other connection types f .eg conical mantle surfaces), but that also the longitudinal axes of these cylindrical (conical etc.) areas of both ends 73 are aligned coaxially with each other. A machine 74 which will be able to carry this out is shown in fig. 12.

Strictly speaking, only about half of this machine is visible; the mirrored left machine part with respect to the plane of symmetry 77 has been omitted for reasons of space. The machine 74 mainly consists of four components, namely an elongated rigid profile 78, which is used as a reference for the longitudinal axis of the machine 74 as well as for the construction of the additional machine components. Approximately in the middle of the profile 78, a device 79 is attached to this for clamping a bamboo tube 4 to be processed. Finally, there are two more processing devices 80, which are arranged on both sides of the clamping device 79 and are likewise carried by the profile 78. Within the framework of a simpler version, a processing device 80 can also be saved if the remaining one can be moved on the other profiler 81 with few handshakes, or if e.g. the clamping device as well as a clamped bamboo tube 4 will be able to be rotated 180°.

A commercially available structural element can be used as profile 78. This preferably consists of a square profile with a square cross-section whose longitudinal sides 82 each have a T-shaped undercut fastening groove 83 running in the longitudinal direction of the profile, cf. fig. 13. In these tracks 83 it will, e.g. in the area of both profile ends, brackets not shown could be attached for repelling the machine 74.

The clamping device 79 comprises two gripper sets 84 and a common operating device 85.

A gripper set 84 is shown in fig. 13. By means of attachment angles 86, a parallel axle bolt 87 is non-rotatably attached to both sides of the support profile 78. On each of the stationary axle bolts 87 in this way is placed an upright plate 88, which is provided for this purpose with a through recess whose diameter corresponds to the diameter of the axle bolt. The plates 88 abut on one side against the relevant attachment angle 86 and are attached at the other end of the relevant axle bolt 87 by means of a non-rotatable attachment on the axle bolt, or pressed gear 89, so that they will indeed be able to be swung around the relevant axle bolt 87, but will not be able to detach from this. The plates 88 are each designed as a two-armed weight arm with a shorter arm 90 extending downwards from the respective through-hole recess and a longer arm 91 extending upwards. By means of a tension spring 92 carried under the support profile 78, the two lower arms 90 of the weight arm are connected to each other and are thereby pulled towards each other until they abut against the longitudinal sides 82 of the support profile 78. The upper arms 91 of the plates 88 in this case take a maximally spread position.

Approximately on the upper part of each plate 88 there is a further through recess for a pivot shaft 93 which is rotatably stored there. Each of these pivot shafts 93 carries a gear wheel 94 on one end and on the other end a plate 95 whose circumference exhibits a concave side 96, e.g. with a hyperbolic pre-race.

The toothed wheel 94 as well as the plate 95 are non-rotatably connected to the pivot shaft 93, respectively. pressed on, clamped (clamping screw) soldered and/or welded. On the other hand, the toothed wheel 94 via a toothed belt 97, which is held tightly tensioned via a device 98, is rotatably connected to a toothed wheel 89 on the fixed axle bolt 87. This achieves that the orientation of the upper plates 95 in space is maintained, regardless of the swing position of the lower plates 88. This function is effectively similar to a parallel guide by means of a rod system of two rods which can be swung parallel to each other.

The upper plates 95 are arranged so that their concave sides 96 face each other. These sides 96 can thereby approach each other when the upper weight arms 91 of the lower plates 88 are moved together, in order to be able to clamp a bamboo stick between them.

For operation of such a gripper set 84, a downward-pulling extension, e.g. a screwed-in bolt 99. Here an operating device 85 engages.

The operating device 85 comprises a pneumatic cylinder 100 arranged under the support profile 78 which is arranged parallel to this. Both on the cylinder housing 101 and on the piston, a coaxially outwardly directed conical tip 104, 105 is attached via each coaxial rod 102, 103. The two rods 102, 103 each engage through a bearing bracket 106, 107, as the entire operating device 85 is stored displaceably on the underside of the support profile 78 in its longitudinal direction.

As the cylinder housing 101 itself is not fixed, it can move limitedly in the longitudinal direction of the support profile 78. If the pneumatic cylinder 100 is pneumatically extended, the conical tips 104, 105 enter between two downward extending extensions, particularly bolts 99 of each gripper set 84, and push them apart. Thereby, the upper arms 91 swing inwards, and the bamboo rod 4 is clamped in the area of both its ends 73 between two concave slopes 95, 96. Thereby a centering of the two ends 73 takes place symmetrically about the vertical longitudinal plane of the support profile, while conical tips 104, 105 act equally on the two arms 90 of a gripper set 84. Centering in height takes place with the help of the concave shape of the clamping jaws 96. Thereby, the exact dimensions, e.g. the diameter of a bamboo stick 4, not of importance, as the pneumatic cylinder 100 automatically shifts in the longitudinal direction until all arms 90 are affected by the same forces.

A bamboo rod 4 centered in this way is thus processed in both its end parts, i.e. protruding surface parts 75, 76 are removed over a predetermined stretch. This is carried out by each processing device 80.

Each processing device 80 comprises a slide 108 with a device 109 for clamping a drilling machine 110, which is displaceable along the support profile 78 by simultaneously aligning the drill chuck coaxially with a processing axis that runs in the middle above the support profile 78, and at a height determined by the strongest receding part of the concave clamping jaws.

When the slide 108, such as by means of side rollers 111 which engage with the longitudinal groove 83 is guided in a parallel displaceable manner, pushed towards the relevant end 73 of a clamped bamboo pipe 4, therefore the axis of rotation of a processing tool 113 which is clamped in the drill chuck 112 of the drilling machine 110 always remains coaxial with the bamboo pipe 4 longitudinal axis, which is predetermined by the fixed tension explained above.

The processing tool 113, which processes the inner and outer sides 75, 76 of the bamboo tube 4 at the same time, is shown in front view in fig. 14. It comprises an inner and an outer cutting tool 114, 115 which handles the processing of the inner side 75, respectively. the outer side 76 of the bamboo tube 4.

The internal cutting tool 114 is in the form of a milling cutter, in particular a cylindrical end milling cutter with a rear-facing attachment extension for clamping in the drill chuck 112. This cutting tool 114 penetrates the cavity of a bamboo tube 4 to at least zone-wise process its inner wall 75 cylindrically.

A further part is attached to the shaft of the cutting tool 114, which, like the outer part of the tool 56, has a bell-shaped shape. Although it may be cast in one piece, in the embodiment shown it consists firstly of an annular disc-shaped part 116 and secondly of a cylindrical part 118 attached to this.

On the annular disc-shaped part 116 there is a backward-facing, cylindrical extension 117, through which extends a radially extending threaded bore for receiving a clamping screw. With this clamping screw, the annular disc-shaped part 116 is fixed on the cutting tool's 114 shaft.

By means of the screws that grip through the annular disc-shaped part 116, this is connected to the cylindrical part. In its front face 119, several teeth 120 are cut out, whose cutting edge, e.g. tips, are slightly bent inwards. When the processing tool 113 is pushed forward, the outer side 76 of the bamboo tube 4 is processed by these teeth, in order here at least zonally to provide surfaces which run along cylinder mantle surfaces and which enable the insertion of the bamboo tube end 73 in a corresponding recess 9 in a connecting element 1, 14, 21, 34, 38.

In order that the cutting tools 114, 115 which during this processing, due to irregular growth, in an emergency engage asymmetrically with the end 73 of the bamboo tube 4, should not be able to expose the processing tool 113 to vibration, this is additionally supported against the cylindrical part 118 outer jacket 121. A further trestle 122 which is attached to the support profile 78 and which surrounds the cylindrical part 118 in a frame-like manner and has several, preferably three or four, rollers 123 which can rotate about pivot axes 124 parallel to the axis of rotation of the processing tool 113, respectively, contributes to this. the longitudinal axis of the carrier profile 78. These rolls 123 press from different sides, e.g. from directions which are offset by 90° or 120° in relation to each other, towards the outer casing 121 of the processing tool 113, so that vibrations thereof are reliably avoided.

When manufacturing bamboo tubes 4 and connecting elements 1, 14, 21, 34, 38, 52 which fit into each other, it must be taken into account that the axis-parallel length of an end region 73 of a bamboo tube 4 which is processed for removal is equal to or if possible somewhat shorter than the depth extent of the annular recess 9 in the relevant connecting element 1, 14, 21, 34, 38, 52 which is to accommodate this, whereby the area 73 of a bamboo tube exposed in this way, i.e. freed from its water-repellent layer is covered by the connecting element 1, 14, 21, 34, 38, 52 and possibly an adhesive layer or the like.

In addition to bamboo tubes as rod elements, the system according to the invention will also be able to use wooden rods 125, 126, e.g. of soft wood, which are either inserted directly as solid rods or can be provided with a coaxial fully or partially through hole 127, e.g. to promote crack-free shrinkage during drying.

Such wooden rods 125, 126 can, if necessary, be inserted coaxially into each other for extension, as can be seen from fig. 15. For this purpose, the ends to be joined together of adjacent rods 125, 126 have designs that fit into each other: In the front side of one rod 125 there is e.g. a circumferential ring groove 128, on the front side of the second rod 126 a complementary ring extension 129. Together these form a form-fitting plug connection which, e.g. by applying adhesive to the surface of one of the plug elements 128, 129 will be able to be fixed to each other. In addition, it is also possible to press or glue into each element a threaded device - on the one hand a screw bushing and on the other hand a threaded bolt - in a central hollow bore 127, so that such rod elements 125, 126 will also be able to be screwed together, in in addition to the formti I fitted plug connection.

Claims (12)

1. System of rod elements (4, 125, 126) which are connected or connectable to each other to form a truss or framework (5), and connection elements (1, 14, 21, 34, 38, 52) which are arranged or can be arranged between the rod elements in the area of all the connection points where two or more rod elements whose longitudinal axes do not run coaxially with each other meet, where a) the rod elements (4, 125, 126) consist of at least one material from high-growing plants, b) the connection elements (1, 14, 21, 34, 38, 52) consists of a solid, regenerative material, and c) at least one end of a rod element (4, 125, 126), a connecting element (1, 13, 21, 34 . that in the area of the connection between a rod element (4, 125, 126) and a connector reading element or an additional spelling element (1, 14, 21, 34, 38; 4, 125, 126), on each of the two bodies (4, 125, 126; 1, 14, 21, 34, 38, 52) a surface (11; 76) which extends along the mantle surface of a cylinder, cone, a prism or a pyramid, as well as at least zonally a surface (10; 75) which runs along a hollow cylinder, cone, a prism and/or a hollow pyramid, e) which surfaces (10; 75; 11; 76) enables a joining according to the plug principle of surfaces located close to each other which are mutually complementary and form a fit which is suitable for locking by means of clamps and/or gluing. 2. System according to claim 1, characterized in that the connection between a rod element (4, 125, 126) and a connection element or a further rod element (1, 14, 21, 34, 38; 4, 125, 126) is designed as a plug connection (30). 3. System according to claim 1 or 2, characterized in that the connection between a rod element (4, 125, 126) and a connection element or a further rod element (1, 14, 21, 34, 38; 4, 125, 126) is made as a clamp (21, 34) or adhesive connection ( 1, 14, 38). 4. System according to one of the preceding claims, characterized in that one connecting element (1, 14, 21, 34, 38, 52) has at least one surface area which exhibits a concave course, in particular a course that follows approximately a section of the mantle surface of a hollow cylinder for connecting the shaft of a rod element ( 4, 125, 126). 5. System according to one of the preceding claims, characterized by at least one rod element (4, 125, 126) having a shaft which is milled to a round shape on the outside. 6. Procedure for producing a truss or framework (5) of rod elements (4, 125, 126) which are to be connected and connection elements (1, 14, 21, 34, 38, 52) which are to be arranged between these in the area for all the connection points where two or more rod elements whose longitudinal axes do not run coaxially with each other meet, where a) there are available rod elements (4, 125, 126) which each comprise at least one segment of a material of high-growing plants, b) connection elements (1,14, 21, 34, 38, 52) of a solid, regenerative material, and c) at least one end of a rod element (4, 125, 126), a connecting element (1, 14, 21, 34, 38, 52) which is to be connected to this and/or the end of a further rod element (4, 125, 126) which is to be inserted, are processed so that they at least zonally display surfaces which run along well-defined geometric bodies, d) characterized by that in the area of the connection of a rod element (4, 125, 126) with a connecting ler additional stave element (1, 14, 21, 34, 38; 4, 124, 126), on each of these two bodies 4, 125, 126; 1, 14, 21, 34, 38, 52) a surface (11; 76) is arranged which runs at least zonewise along the mantle surface of a cylinder, cone, prism or pyramid, as well as one at least zonewise along a hollow cylinder -, hollow cone, a hollow prism and/or a hollow pyramid continuous surface (10; 75), e) and that the surfaces processed in this way (10; 75; 11; 76) are joined according to the plug principle with adjacent surfaces that are complementary with each other and form a fit that is suitable for locking by means of clamps and/or gluing. 7. Method according to claim 6, characterized in that the body and/or the surfaces of the parts (4, 125, 126; 1, 14, 21, 34, 38, 52) which are to be connected to each other are machined abrasively, especially chip separation. 8. Method according to claim 6 or 7, characterized in that both ends (73) of a rod element (4, 125, 126) are processed in such a way that the longitudinal axes of symmetry of the processed areas (75; 76) are in line with each other. 9. Device for producing a truss (5) of rod elements (4, 125, 126) to be connected, and of connection elements (1, 14, 21, 34, 38, 52) to be placed between these rod elements at all such locations where two or more rod elements whose longitudinal axes are not mutually coaxial meet, where a) the rod elements (4, 125, 126) consist of a solid, regenerative material, and b) the connection elements (1, 14, 21, 34, 38, 52) consists of a solid, regenerative material, and where c) at least one connection element (1, 14, 21, 34, 38, 52) and/or the ends (73) of rod elements (4, 125, 126) to be connected to the connection element and/or each other, are processed in such a way that they at least show surfaces in zones (10; 11; 75; 76) extending along well-defined geometric bodies characterized by) at least one tool (56, 113) designed as an abrasion tool, in particular as a cutting tool, to machine at least one connecting element (1, 14, 21, 34, 38, 52) which is made of a rigid, regenerative material and/or the ends (73) of rod elements (4, 125, 126) which are each made of at least one segment of a material of high-growing plants and which are to be mounted to the connecting element or to each other in such a way that they achieve surfaces (10, 11; 75, 76) which, at least in selected areas, run along well-defined geometric bodies, whereby the machined body (4, 125, 126; 1, 14, 21, 34, 38, 52), in the area of connection between a rod element (4, 125, 126) and a connection element (1, 14, 21, 34, 38), at the same time a surface is formed which at least in selected regions run along the lateral surface (11; 76) of a cylinder, cone, prism or pyramid, so well as a surface (10; 75) which, at least in selected areas, runs along or a hollow cylinder, hollow cone, a hollow prism and/or a hollow pyramid e) which surfaces (10; 75; 11; 76) enable a joining according to the plug principle of surfaces located close to each other which are mutually complementary and form a fit suitable for locking by using clamps and/or gluing. 10. Device according to claim 9, comprising at least one tool (113) for processing the ends (73) of a rod element (4, 125, 126), characterized by the device (84) for clamping a rod element (4, 125, 126) in such a way that both its ends (73) are parallel, respectively. aligned concentrically as possible with the longitudinal axis of the processing device (74). 11. Device according to claim 10, characterized wooden device (108) at each end of a clamping device (84) for holding and/or mounting a processing tool (113). 12. Device according to one of claims 9 - 11, characterized wood device (111) to control the processing tools (113) or their holders (108) in the feeding direction along the longitudinal axis of the processing device (74).