FI111915B - Composite wood construction - Google Patents

Description

11191b

Liittopuurakenne

Field of the Invention

The present invention relates to a composite wood structure according to the preamble of claim 1.

5 Such a composite wood structure is intended for the production of wood panels as well as various wooden columns and beams.

Background of the Invention

As good quality wood raw material is becoming rarer and more and more expensive, it is becoming increasingly common to produce wood-based laminated boards and beams of 10 joints. These are commonly used in the manufacture of large and large uniform wood surfaces, as well as in the construction of wooden beams, for which even greater load-bearing capacity and durability are desired than solid wood structures.

By gluing structural widths, i.e. wooden slats, side by side and superimposed on one another, it is relatively simple to produce large uniform wood planks commonly used in the carpentry industry to make various furnishings, in the construction industry as coating materials, as support materials and so on. The use of this type of wood is run-20, and the demand for planar wood is expected in the future: ·. due to their strong ecological nature and impressive appearance • I * * v>.

It is known to produce glued beams by gluing in parallel and / or overlapping wooden slats, which are pressed together with strong clamps in two directions, vertical and lateral, as the glue cures. This way: "i can be used to build large uniform and durable planar wood panels and beams with an almost solid wood appearance. The glue glue surfaces improve the load-bearing capacity and durability of the solid wood structure. V. Such glue wood components can then be used in the woodworking industry. Various known solutions for the production of glulam are disclosed in, for example, Fl 23624, SE 444 635, DE 37 06 710 and DE 197 26 923.

However, there are serious problems with this known technology. As the tree grows in nature, it constantly strives toward the light, usually on its trunk: 35 twisting. Thus, as the wood grows, the wood material is often twisted and the same twisting continues even after the wood has been felled and put into use, for example, as furniture material. For this reason, there are always stresses in the wooden slats used to make the glulam 111915 2. These stresses on the wood slats cause stresses on the glued beams and boards which twist them and thus cause the glued beams and boards to twist and crack. This in turn reduces the appearance and durability of the glulam timber structures. 5 For this reason, a board made of glued wood is usually so curved that the table stands on its base with three legs and swings. Secondly, over time, the natural variability of the air humidity and the resulting deformation of the wood slats will cause the laminated chipboard to crack and to weaken its structure.

Another serious problem associated with the manufacture of prior art adhesive board structures is the pressing method used for gluing, in which the gluing board or beam must be pressed from two directions, i.e. top and side, during gluing. This results in complicated and large presses which are expensive. The compression also requires the compression-15 structure to have parallel compression surfaces.

A third problem with the prior art is the production of large array-plate layers. Particularly in the manufacture of contoured planes, the material wastage is high, because in the state of the art, firstly, a rectangular board of the desired board contour must first be produced, whereby the final contoured board is sawn, resulting in a large amount of waste. The reason for the formation of wastes is the compression technique used in the gluing step described above, which requires: V: a rectangular sheet blank for successful compression.

Also known is a blank for the manufacture of an adhesive beam board in which the blanks are bonded together using a sharp-edged gripping surface. The machining of such a sharp edged grip surface is problematic because the machining of sharp edged molds places high demands on the durability of the tools. A poor tool will degrade the quality of the machined gripping surface and thereby cause fitting problems and costs in the loss of material i '30. The preparation of the blank also requires high precision and causes

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:: commendable waste of wood.

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BRIEF DESCRIPTION OF THE INVENTION »»

The present invention has been significantly reduced to the known; disadvantages of technology and the resulting composite wood structure, which structure allows for simpler and more economical manufacture of solid wood panels, beams and columns for a variety of applications with varying requirements.

This is achieved by having the composite wood structure having the features defined in the claims according to the present invention. Specifically, 5 min, this composite wood structure according to the invention is essentially characterized by what is stated in the characterizing part of claim 1.

Preferred embodiments of the invention are claimed in the dependent claims.

The invention is based on the realization that at least two structural members that are mechanically joined to one another by a superposed structure of wood are substantially symmetrically shaped with corrugated surfaces. This solution provides several significant advantages.

Such a symmetrical corrugated structure of the joint surface is advantageous in many ways. First, the corrugated surface expands the structure of the composite wood structure with a stiffening and cohesive friction surface relative to the surface. Second, Wave peaks and troughs of overlapping joining surfaces overlap each other to stiffen the structure of the wood structure, thereby preventing the board from being twisted but forced to remain straight. Third, the waves peaks and troughs of the joining surfaces pressed overlapping each other guide the wooden beams forming the composite wood structure to suitably align during the attachment step. For example, when gluing wood slats to one another by gluing, the gluing step can be carried out by applying a clamping force only in one direction from the top of the board, i.e. at an angle perpendicular to the outer surface of the composite wood structure. The advantage of this is that, for example, large size glued laminated boards can be made in their final form without the significant waste of syn. This is because pressing from the top only allows the sheet to be manufactured even before it is glued to almost the correct shape. In addition: * 30 one-way squeezer is significantly simpler and more economical in its two-sided design.

:. ·. In order for the structure to function, the distance between the successive wave peaks and the troughs of the wavy shape of the junction surface in each member is preferably constant and the wave height is substantially constant. Preferably, the sinusoidal shape of the junction surface has proven to be a waveform.

In its preferred embodiment, the waveform also comprises a substantially straight portion between the wave peak and the 411191b wave bed. The sinusoidal shape is round-edged, with the advantage that machining tools do not require sharp-edged parts, which improves their durability. By designing the wave height such that it pierces more than one annual growth-5 ring, a structure significantly increasing the strength of the final joint structure is obtained, particularly when gluing the wood structure.

In a preferred embodiment of the composite wood structure according to the invention, at least one corrugated planar 10 structural element is arranged between the two or more structural elements forming the wooden structure. The waveform of this planar component substantially follows the waveform of the joint surface of the composite wood structure. The planar component is preferably of a hard and tough material, for example metal or fiberglass. This planar insertion member of the composite wood structure can substantially improve the durability and load-bearing capacity of the composite wood structure 15. In addition, the planar component improves the toughness of the composite wood structure in the event of its possible cracking. Thus, for example, an adhesive wood structure with such a planar structural member to be inserted into the composite wood structure is at least three times more load-bearing than the corresponding solid wood structure.

20 Such a composite wood structure with a planar component still achieves much better fire resistance than the conventional wood structure. Also, the final wood material of the composite wood structure: '.': Can be thinned without compromising durability, which also reduces its weight, volume and material consumption, which is advantageous especially when using valuable hardwoods.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the invention will now be described in more detail with reference to the accompanying drawings, in which: FIG. 1 is a cross-sectional view of a substantially planar wood slat 30 having a corrugated wood structure according to the invention; of wood according to the invention, which are - *: ** arranged to overlap each other with corrugated joints

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• facing each other to form a composite wood structure according to the invention,

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111915 5 Figure 3 shows a cross-sectional view of an adhesive sheet structure consisting of the wood slats of Figure 2 forming a composite bore structure according to the invention, Figure 4 showing two wood slats of Figure 1 arranged intermittently overlapping corrugated joints Fig. 5 is a cross-sectional view of an adhesive plate structure consisting of wood slats of Fig. 4 with 10 planar structural members disposed between their joining surfaces, and Fig. 6 showing, for example, mechanically joining wood slats forming a composite wood according to the invention.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS Some preferred embodiments of the composite wood structure and their preparation are described below with reference to the above figures. Herein, the solutions comprise reference numerals corresponding to those used in this specification with reference numerals.

Thus, a preferred embodiment 20 of the wood composite lattice 2 forming the present composite wood structure 1 comprises a structure as shown in Fig. 1. The wood grate then comprises a structural part made of either raw wood or wood processed in a manner known per se, such as heat-treated or pressure-impregnated wood. The wood grille of Figure 1 has planar side surfaces 21 which are connected by an upper surface 22 and a lower surface 23. In the embodiment of Figure 25, the lower surface of the wood grille simultaneously forms one joint surface 23 of the composite wood structure.

As can be seen in Figure 1, the joining surface 23 of the wood slat 2 is machined, for example, by milling or planing. The waveform is • preferably sinusoidal and symmetrical, with the successive wave 51 of the wave 30, i.e. the wave portion further from the upper surface 22 of the wood slatt 2, and. the distance between the trough 52, i.e. the wave portion closest to the upper surface 22 of the wood slatt 2, is of constant length and the wave height 53 is of constant height throughout the waveform. The rising and falling portion of the waveform has an i * ': preferably a symmetrical straight portion 54 conforming to the waveform.

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According to a preferred embodiment, the wood slats 2, 3 and the resulting waveform are dimensioned as follows. The width of the wood slats, i.e. the width of the upper surface 22, 23, is substantially 130 mm. The sinusoidal waveform of the coupling surface 23, 33 comprises four complete waves. It is essential to the functionality of the composite wood structure that the structure of the joining surface of the interconnected wooden slats comprises an equal length of waves, and that these waves are machined to the same location in each of the wooden slats. In this preferred embodiment, the wavelength is 32.5 mm and the wave height 53 from the peak 51 to the base 52 is 5.88 mm. The wave radius 10 of the wave base 52 of the wave peak 51 is 10 mm. The symmetrical waveform portion 54 on the rising and falling portion of the waveform has a length of 8 mm and is symmetrically centered on the rising and falling portion 54 of the waveform. Naturally, the proportions may differ from the above dimensions. The waveform may also be non-sinusoidal, such as a square wave at suitable mit-15 ratios.

As can be seen from Figure 1, in this embodiment, the wood slatted 2 is shaped such that the top surface 22 of the slat is substantially flat, although it may also be of other types, such as wavy, as shown in Figure 6. The top surface of the wood slats is conventionally machined to be sanded. The side surfaces 21 of the wood slats are planar. They are preferably machined to the underside of the wood slat, i.e. the joining surface 23 i '· ,,, so that the angle α between the top surface of the wood slab and the side surface. , is less than 90 °. The wood slats are thus tapered towards the joint surface.

,:. The wooden slats are dimensioned such that, for example, the parallel wooden slats 2 and 3 arranged against the rails according to FIG. ground closely and overlapping each other such that the top surfaces 22 and 32 of the wood slats are substantially parallel. In this case, the corrugated connecting surface 33 of the lower · · '··' side wooden slat 3 points upward and the connecting surface 23 of the wooden slat 2 above it points downward.

When pressing the wood slats against each other, the corrugated connecting surfaces (23, 33) guide the wood slats in relation to each other so that the peaks 51 of the upper wood slats: 2 are aligned with the corresponding troughs * · «52 of the lower wood slats 3 and vice versa. The rising and falling portion of the waveform has a symmetrical wave-shaped straight portion I * f • 35 54, which improves the alignment of the wood slats during the compression step.

Preferably, the wave height is selected so as to extend through several annual passages, thereby reinforcing the joint between the wood slats. The wavelength, in turn, is preferably substantially larger than the total thickness of the wood slats, making it easy to work with sufficient durability, thereby facilitating the positioning of the wood slats in the opposite position.

5 When gluing the wood slats 2 and 3 together by gluing, the glue then also reaches between the side surfaces 21 and 31 of the parallel wood slats during the pressing step. As a result, the slant angle α of the side surface is dimensioned such that there is a gap of up to 0.5 mm between the two parallel wood slats 2, 3 and at the end of the upper wood surface 22, 32 the wood slat 10 is oversized so that the parallel wood slats 0.1 mm against each other to form a very tight joint, which is immediately sanding ready.

Fig. 3 shows a structure of glued laminated board consisting of wooden slats 2 and 3 as described above, forming a joint structure 15 according to the invention. For example, the glulam board is manufactured by, for example, loading, in the first step, the pre-machined Good quality wood slats 3 forming the surface of the gluing board onto the base with the top surface 32 facing down and the corrugated joint surface 33 facing up. In the second step, adhesive 5, usually an elastic adhesive, is applied to the bonding surface 33. In the third step, the joining surface 33 is laid on the substrate 20 over the wooden slats upwards, forming the wooden slats 2 forming the bottom surface of the glued laminated board, with the joining surface 23 facing downwards, whereby the corrugated joining surfaces overlap. It is also advantageous to use a lower quality wood veneer on the underside of the glued laminated board. In the fourth step, a flat clamp is pressed from the side of the bottom surface of the glulam board, i.e. perpendicular to the bottom of the glueboard, with the wood slats tight against each other, so that lateral clamping of the glueboard is not required.

Figure 3 shows a wavy shape of the joint surface of the present composite wood structure. Such a corrugated joint surface significantly increases the mutual contact surface of the wood slats '·' 30 as compared to the conventional direct joint surface. This results in better bond strength and composite wood structure; : improved load-bearing capacity and durability. Corrugated wood structure wavy • • · *. ···. the structure stiffens the structure against warping and twisting, leaving the plate • * [· * straight and flat. As can be seen in Fig. 3, the wooden slats 2, 3 are: 35 stacked in relation to each other in a board, with each wooden slat being in contact with at least two other wooden slats. In this way, cracking of the composite wood structure 111915 8 - in this case glued laminated board - has been eliminated and any damage caused by cracking has been prevented.

Figure 4 illustrates another preferred embodiment of a composite wood structure having two overlapping and overlapping joints 23 and 33 of stacked wood strips 2 and 3. Therein, a wavy shape of a substantially planar structural member 4 is inserted between the joining surfaces of exactly corresponds to the waveform of the joining surface of the slats. The planar component 4 is made of a hard and tough material such as metal, fiberglass, plastic, rubber or the like.

In the embodiment of Fig. 4, the waveforms of the joining surfaces 23 and 33 of the wood slats 2 and 3 are sinusoidal and symmetrical, with a wavelength 15 between the successive waveguide 51, that is, farther from the top of the wood slab 22 . The waveforms 52 of the waveform 52 forming the lower surface of the composite wood structure are slightly or approximately 1 mm deeper than the waveforms 52 of the upper surface forming component 3. In this way, the differing thermal expansion properties of the wood slats and the planar structural member 4 are compensated. The deeper troughs of the lower surface of the wave-20 allow for a small thermal expansion expansion with the elastic adhesive material 5, the thermal expansion coefficient of the planar component 4; · When the action is different from the corresponding coefficient of wood. Otherwise structure: Y: as described above.

Fig. 5 shows a glued laminated board consisting of wooden slats 2 and 3 as described above, between which a planar structural member 4 is arranged to form a composite wood structure of the present type. Such glued laminated wood panels are manufactured, for example, by loading, in the first step, high quality wood slats 3 forming the surface of the glued laminated board to the substrate with the upper surface 32 facing down and the corrugated connecting surface 33 facing up. In another: · In step 30, adhesive 5, i.e. an elastic adhesive, is applied to the joint surface 33. In the third step, a molded or extruded planar structural member 4 is applied to the joint surface 33. In the fourth step, adhesive 5 is applied to the exposed surface of the structural member 4. In the fifth step, an adhesive wood panel is applied over the exposed surface of the structural member 4. the wood slats 2 forming the bottom surface '35 downwardly of the connecting surface 23, i.e. with the corrugated gluing surfaces and the planar component therebetween overlapping 111915 9. It is also advantageous to use a lower quality wood veneer on the underside of the glued laminated board. In a sixth step, a flat clamp is pressed from the side of the bottom surface of the gluing board, i.e. perpendicular to the bottom surface of the gluing board, with the wooden slats and the component between them being pressed tightly against each other. Due to the structure of the corrugated joint surface, the lateral compression of the glued laminated board is not required due to the corrugated structure of the glued laminated boards 2, 3 and the component 4.

Fig. 5 shows a glued laminated board according to a preferred embodiment of the composite bore structure according to the present invention, in which a corrugated planar structural component 4 is inserted between the joint surfaces 23 and 33 of the wooden slats 10. The load-bearing capacity is at least three times that of conventional solid wood glulam. In addition, the planar component 4 pa-15 sheds the toughness of the structure if the composite wood structure is cracked. The structure stiffens the composite wood structure against warping and twisting, so that the board made of it remains straight and flat. Such a composite wood structure comprising a planar structural component achieves much better fire resistance properties than the wood structure alone, since the fire cannot propagate as an open flame throughout the structure, but especially when the structural element 4 is metal, the fire can only propagate through the metal under thermal stress. The thickness of the wood material of the composite wood structure, i.e. the thickness of the individual wood fins 2 and 3 in such a composite wood structure comprising component 4, can be reduced without loss of durability, which also reduces weight, volume and material consumption.

The thickness of the wood slats 2 and 3 forming the composite wood structure 1 from the top surface 22 or 32 to the joint surface 23 or 33 may vary, as well as the width of the wood slat measured between the side surfaces. However, it is preferable to make the upper surface and the lower surface of the composite wood structure from wood slats of the same strength. As will be readily apparent from the foregoing, such a composite wood structure can also advantageously and easily be made of glulam boards and beams of various thicknesses. :. ·. Wood slats can be made to varying thicknesses, according to suitable dimensions. According to the required thickness of the sheet, the sheet is made by cutting its lower surface into one thickness of wood slats and the upper surface of another thickness of wood slats. It is also possible to fabricate a composite wood structure using a plurality of overlapping layers of wood slats as shown in Figure 6. In particular, the corrugated joint structure may be utilized, where necessary, for larger glued laminated board and beam thicknesses by making the board or beam from multiple stacked layers of wood. In this case, it is advantageous to fabricate at least the slats on the intermediate layers of the structure on both sides of the waveguide, whereby a corrugated adhesive surface is provided on both sides of the wood slats. This makes it possible to produce high load bearing laminated boards and beams.

Because the manufacture of glued laminated board requires compression in only one direction, for example, an arc-shaped plane can be made from approximately approximately arch-width wooden slats, resulting in very little waste. The disc made of high-strength wood slats is also ready for grinding immediately after removal from the press. It no longer has to be planed to the desired thickness, which saves many laborious manufacturing steps.

Figure 6, in turn, shows a composite wood structure comprising three overlapping wood strips 2, 3 and 6. Such a structure can be made based on its end use, either as shown in Fig. 3 from corrugated wood strips or by having the outer surfaces of the outer wood strips planar. In order to improve the durability and load-bearing capacity of the composite wood structure, a corrugated planar structural member as shown in the figure by a dashed line can be fitted between the joining surfaces of the wood slats 2, 20 3 and 6.

; '* · Particularly in the manufacture of load-bearing wooden structures such as pillars, posts and beams, it is advantageous to mechanically connect the wooden slats to each other, e.g. When forming a composite bore structure from at least three overlapping slats, a tongue-and-groove connection is easily provided at least at one end of the supporting wood structure. In such a tongue, for example, · the end of the I · wood tile 6, which is arranged between the two outermost wooden slats 2 and 3, is extended a distance from the ends of the outermost wooden slats. As the load-bearing structure is extended, it is fitted with a composite structure in which the ends of the alternately outer slats are extended farther than the end of the inner slat. Thus, a conventional male-female tongue and groove joint is formed, such as: stiffenable and lockable, e.g. The continuous ·· * thus obtained is very durable due to the stiffness provided by the corrugated shape of the wooden slats' · *.

• · 1 35 It is understandable that there is no explanation above and related patterns

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\: Only intended to illustrate the present excess wood structure. Thus, the invention will not be limited solely to the embodiment described or claimed, but many variations and modifications will be apparent to those skilled in the art, within the scope of the inventive concept defined in the appended claims.

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Claims (9)

A composite wood structure (1) comprising at least two wooden lamellas (2, 3, 6) arranged one above the other and each of the lamellas comprises two flat side surfaces (21, 31) and an upper surface (22). , 32) and / or a touch surface (23, 33) for joining the side surfaces with each other, the touch surfaces being arranged in pairs in opposite positions to each other and the touch surfaces being formed to be substantially road-shaped, characterized in that the touch surface (23, 33). ) road shape has a length substantially greater than the thickness of the wooden lamella and that the height of the road shape delimited by the top of the cradle (51) and the bottom of the cradle (52) is arranged to extend through more than one of the wooden plants . Composite wood structure (1) according to claim 1, characterized in that the contact surface (23, 33) is symmetrically road-shaped, wherein the path shape of the contact surface (23, 33) of each of the wood slats (2, 3) has a constant the distance between the top of the cradle (51) and the bottom of the cradle (52) and the road height (53) are substantially constant. Composite wood structure (1) according to claim 2, characterized in that the path shape of the contact surface (23, 33) has the shape of a sine curve. Composite wood structure (1) according to any preceding claim • characterized in that the composite wood structure comprises a sandwich structure, · which has at least one middle part and to this adjacent outer parts. 5. A composite wood structure (1) according to claim 4, characterized in that: the middle part comprises a substantially pian building part (4) designed to accommodate a road shape and arranged between two substantially parallel wooden louvers. Composite wood construction (1) according to claim 5, characterized in that the flat building part (4) comprises a hard and tough material. 111915 7. A composite wood structure (1) according to claim 4 characterized in that the middle portion comprises at least one wooden lamina having a vault-shaped and substantially parallel contact surface, which lamella is arranged between two substantially parallel lamellas. Composite wood structure (1) according to any preceding claim, characterized in that the outer surfaces of the composite wood structure have a substantially planar construction. Composite wood structure (1) according to any preceding claim, characterized in that an elastic adhesive (5) is arranged to the contact surfaces (23, 33) for joining the wood lamellae.