EP0388507B1 - Wooden beam and method for manufacturing the same - Google Patents

Abstract

The invention relates to a composite wooden beam and to a method for manufacturing the same. According to the invention, for maximum utilisation of the roundwood portion, the wooden beam is composed of a plurality of individual elements which enclose a hollow space 5 and the touching edge regions 8 of which each have the form of a truncated pyramid, so that by turning the respectively adjacent individual elements a wooden beam of constant cross-section can be produced from a conical roundwood portion, the systematic annual ring progression leading to a number of advantages. <IMAGE>

Description

The invention relates to a method for producing a wooden beam according to the preamble of claim 1.

It is known from SE-A-115 667 to produce wooden beams in a composite construction, the wooden beams or glue structures having a central cavity. The trunk is worked on four opposite surfaces and then quartered. The quartered trunks are then rotated about their respective longitudinal axes and glued together again. With this procedure it is only possible to produce composite wood beams with a square cross-section.

In the known wooden beams, the individual elements are each produced with a similar cross-section, with a relatively large amount of waste occurring in the round wood sections serving as the starting material. If, in the prior art, the individual elements made from round timber sections have a non-constant cross-section, the cross-section of the finished wooden beam also tapers, so that, in order to obtain parallel shapes, it must subsequently be divided into individual pieces and processed.

The invention has for its object to provide a method for producing a wooden beam according to the preamble of claim 1, in which the waste or material loss can be minimized to produce a wooden beam with a constant cross-section.

This object is achieved with the features of claim 1.

The wooden beam produced with the method according to the invention is distinguished by a number of considerable advantages. There the individual element is shaped like a truncated pyramid, it is possible to use the naturally existing conicity of a log section without a reduction to a constant cross-sectional area of the starting material being necessary before its further processing. The amount of residual material obtained during processing can thus be considerably reduced, since the individual elements can be put together to form a wooden beam, the cross section of which, by suitable turning or appropriate assignment to one another Length is constant, and which corresponds approximately to the average diameter of the log section used. Since the truncated pyramid-like parts represent the areas of the individual elements which are in contact with one another, intimate contact of the individual individual elements is ensured, as a result of which a high degree of strength can be achieved.

Four individual elements will advantageously be combined to form a wooden beam. This shape has the advantage that the four individual elements form the four corners of the square or rectangular hollow beam due to their two mutually perpendicular outer surfaces.

The side of the individual element facing the cavity is preferably frustoconical, while the edge regions of the individual element which adjoin an adjacent individual element are truncated pyramid-like. According to the invention, it is possible to process raw and conical (woody), but preferably debarked, log sections or logs into corresponding beams. It is only necessary to process the edge areas, which are to serve for the abutment of the adjacent individual element, in the manner of a truncated pyramid. However, since these areas make up a very small area in relation to the total circumference of the round starting material, a considerable saving effect can be achieved. It is possible to use a high percentage of the raw material.

In order to ensure a constant cross-sectional area of the wooden beam over its length and to ensure a clean connection of the individual individual elements, the individual elements are each given an inclined angle with respect to the truncated pyramid-like areas.

In a further, particularly advantageous embodiment of the invention, it is provided that the individual element is provided with at least one slit on the side facing the cavity, this favors the course of tension in the event of fluctuations in wood moisture.

In the case of wooden beams, which are visible on the end face, it is advantageous to provide them with a cover on the end face, which can be attached or inserted.

Furthermore, it is possible according to the invention to profile the wooden beam on its surface or to process it in some other way, as is customary with solid wooden beams.

Depending on the desired cross section of the finished wooden beam, the individual pieces can also have outer surfaces of different widths, for example to arrange the central cavity off-center, so that further machining operations, for example notches, recesses or the like, can be provided on one of the sides of the wooden beam.

In a particularly favorable further development of the invention, it is provided that the edge regions of the individual element with which it is in contact with an adjacent individual element are structured. The structuring can be carried out in the form of a tongue and groove configuration, or in a similar manner, in order to ensure a stronger connection between the individual individual elements.

In addition to the individual elements, add-on parts can be provided on the wooden beam, for example additional boards, facings or the like, and it is also provided that a high support is formed by several wooden beams connected to one another.

The method according to the invention is simple in relation to the usual methods for cutting open a log section, few work steps are required and there is particularly little waste or residual material. The log section can be subdivided into individual elements by sawing, knives or milling.

Furthermore, it is possible according to the invention to produce the individual elements for a wooden beam from different starting sections, for example in order to be able to take into account different conicalities or curvatures of the round wooden section.

In an advantageous embodiment of the method it is provided that, in a first processing step, two individual elements are initially aligned with one another and machined in the form of a truncated pyramid at their edge regions - and that the individual elements are then connected in pairs, and that in a second processing step the two pairs of individual elements on their edges are truncated pyramid-shaped and connected to the wooden beams. This procedure essentially allows to divide round, conical base material into the four individual elements by separating cuts, without having to carry out any work on the circumference of the base material. After the associated individual elements have been turned and aligned, it is now possible to simultaneously machine the connecting edge areas of the two individual elements in one processing step, for example by means of a wider milling tool or the like, so that they have in particular the same helix angle. In addition, it is possible to precisely determine the later dimension of the wooden beam using the working width of the tool. The subsequent simultaneous processing of the two pairs of individual elements takes place in an analogous manner.

As an alternative to this, it is also possible according to the invention to process the outer contour of the round timber section in the form of a truncated pyramid before the separation or in the course of the separation, or to profile the half-timber in the manner of a truncated pyramid before (or in the course of) the quartering.

According to the invention, different angles of inclination of the starting material, i.e. of the round - truncated cone-shaped logs, it can be beneficial if the log section or the separate individual pieces are measured to determine the angle of the truncated pyramid and / or to determine the machining of the edges.

Fig. 1

eine Stirnansicht sowie eine Seitenansicht eines halbholzförmigen Einzelstückes, das pyramidenförmig profiliert und zu Viertelstücken getrennt ist.

Fig. 2

eine Stirnansicht eines Ausgangsabschnittes, nach Unterteilung in Einzelelemente und eines Mittelstückes.

Fig. 3

eine stirnseitige Ansicht, ähnlich Fig. IV, bei welcher aus dem Ausgangsabschnitt mehrere Kernbohlen ausgeschnitten wurden,

Fig. 4

eine stirnseitige Ansicht zweier zugeordneter Einzelelemente mit jeweils einer Längsschlitzung,

Fig. 5

stirnseitige Ansicht eines erfindungsgemäßen Holzbalkens, welcher aus einer größeren Anzahl von Einzelelementen zusammengesetzt ist und an einer Fläche eine Außenstrukturierung aufweist,

Fig. 6

eine Seitenansicht zweier Ausführungsbeispiele des erfindungsgemäßen Holzbalkens mit stirnseitigen Blenden,

Fig. 7

eine Stirnansicht und eine Seitenansicht eines erfindungsgemäßen Holzbalkens, welcher über die Länge unterschiedliche Querschnittsstrukturierungen aufweist,

Fig. 8

eine Stirnansicht eines weiteren Ausführungsbeispiels des erfindungsgemäßen Holzbalkens,

Fig. 9

Stirnansichten weiterer Ausführungsbeispiele des erfindungsgernäßen Holzbalkens mit aufgesetzten Anbauteilen,

Fig. 10

Stirnansicht eines erfindungsgemäßen Holzbalkens mit u.a. vier halbholzähnlichen Einzelstücken,

Die Fig. 1 zeigt im oberen Bereich eine Stirnansicht sowie im unteren Teil eine Seitenansicht eines konischen Rundholzabschnittes, welcher unterschiedliche Durchmesser am Stockbereich und am Zopfbereich aufweist. Die Fig. 1 zeigt das Ausgangsmaterial, nachdem jeweils die Kernbohle 13 und die Randbereiche 8 durch rechtwinklig zueinander erfolgte Längsschnitte geteilt und somit Einzelelemente 1-4, 13 gebildet wurdenThe invention is described below using exemplary embodiments in conjunction with the drawing. It shows:

Fig. 1

a front view and a side view of a half-wood-shaped single piece, which is profiled pyramid-shaped and separated into quarters.

Fig. 2

an end view of an output section, after subdivision into individual elements and a center piece.

Fig. 3

3 shows an end view, similar to FIG. IV, in which a plurality of core planks have been cut out from the starting section,

Fig. 4

an end view of two assigned individual elements, each with a longitudinal slot,

Fig. 5

frontal view of a wooden beam according to the invention, which is composed of a larger number of individual elements and has an external structure on one surface,

Fig. 6

2 shows a side view of two exemplary embodiments of the wooden beam according to the invention with front panels,

Fig. 7

2 shows a front view and a side view of a wooden beam according to the invention, which has different cross-sectional structures over its length,

Fig. 8

2 shows an end view of a further exemplary embodiment of the wooden beam according to the invention,

Fig. 9

End views of further exemplary embodiments of the wooden beam according to the invention with attached attachments,

Fig. 10

End view of a wooden beam according to the invention with, inter alia, four half-wood-like individual pieces,

1 shows an end view in the upper region and a side view in the lower part of a conical log section which has different diameters at the pole region and at the plait region. 1 shows the starting material after the core plank 13 and the edge regions 8 have been divided by longitudinal cuts made at right angles to one another and individual elements 1-4, 13 have thus been formed

FIG. 7 shows an end view and a side view of the finished wooden beam 14, from which both the essentially central cavity 5 can be seen and the one that is mutually turned Assignment of the individual elements 1-4. The individual elements 1-4 are each connected to one another in the area of the edge regions 8, for example by gluing, nailing or the like.

In order to be able to subdivide into the individual elements 1-4 and to assign them to a wooden beam 14 with a constant cross section, a measurement of the output beam 15 is advantageous. It is possible, starting from the mean diameter of the starting section 15, to determine the maximum possible cross section of the finished wooden beam 14 and to determine the corresponding bevels of the frustum-like edge region 8.

2 and 3 each show end views of an output section 15 already divided into individual elements 1-4, in which one or more core planks or middle pieces 13 have been cut out. These can be used separately.

In Fig. 4, the assignment of two individual elements 1 and 2 is shown in the front view, which are each provided with longitudinal slots 9, which prevent wood tension, and thus a distortion of the individual elements.

According to the invention, it is possible to design any variations on the arrangements shown in FIGS. 2 and 3.

Fig. 5 shows cross-sectional views of wooden beams, e.g. similar to log building. It is possible to profile the wooden beam, for example to create corresponding optical effects, or to seal one another.

An embodiment is shown in FIG. 6, in which the front ends of the wooden beams 14 are each closed by means of an aperture 10 in order to seal the cavity 5 both optically and technically. The aperture 10 can be put on or inserted.

The embodiment of the wooden beam according to the invention shown in FIG. 7 shows that the individual elements 1-4 have different side lengths can have, so that the cavity 5 is arranged off-center by a certain amount. In this way, recesses 17 or notches 16 can be worked out. The respective edge areas 8 of the individual elements 1-4 have different widths 18, 19.

8 shows various possibilities for profiling the individual elements 1-4 at their edge regions 8, for example by means of gradations. Tongue and groove designs, by inserting a separate groove or similar to improve a connection between the individual elements 1-4.

FIG. 9 shows the possibility of connecting additional attachments, for example boards or beams, to the wooden beam 14 according to the invention in order to increase its strength and / or cross section.

Fig. 10 shows a composite of four half-wood-like individual pieces (21) with additional attachments.

The invention is not limited to the exemplary embodiments shown; rather, there are many possible modifications and modifications for the person skilled in the art based on the basic principle, the outer regions of the log section forming the coreless inner region of the composite beam according to the invention, while the yield of the conical log path is used.

Claims (6)

1. A method for manufacturing a wooden beam in composite construction, comprising a plurality of individual truncated-pyramidal elements (1-4), surrounding a cavity (5) and connected to each other and extending in the longitudinal direction of the wooden beam (14), characterised in that, in order to produce the individual elements (1-4) of the wooden beam (14) to be manufactured, a core plank or a central piece (13) is initially cut out of each conical round-timber section (15), each of the two resulting outer segments of the trunk are machined on three separate outer sides in the manner of a truncated pyramid with identical angles of slant in pairs and subsequently the outer segments of the trunk are separated at right angles to the cutting surface for the core plank, and four selected individual elements (1-4) in each case are then secured together by adhesion with their longitudinal axis and cross section turned in a suitable manner in pairs to form a wooden beam (14).
2. A method according to Claim 1, characterised in that the individual elements (1-4) for a wooden beam (14) are produced from different round timber sections (15).
3. A method according to one of Claims 1 or 2, characterised in that the wooden beam (14) is profiled on the surface thereof
4. A method according to one of Claims 1 to 3, characterised in that the individual element (1-4) is provided with at least one slot (9) on the side facing the cavity (5).
5. A method according to one of Claims 1 to 4, characterised in that the wooden beam (14) is provided with a panel (10) at the end.
6. A method according to one of Claims 1 to 5, characterised in that in addition to the individual elements (1-4), attachments (11) are connected to the wooden beam (14).

Images