SE534587C2 - Wooden chipboard of two glued boards with vaulted arch channels - Google Patents

Abstract

SUMMARY The invention relates to a manufacturing device for and a wood chipboard built up of two glued boards (3), each comprising an outwardly facing (5) and an inwardly facing side (7), recessed grooves (9) of at least one inwardly facing side (7) forming parallel channels (k) in the wood chipboard (1), and an adhesive surface (11) between the boards (3) in the position between the grooves (9). The adhesive surface (11) between two adjacent grooves (9) in a disc (3) forms a base foundation (13) for a support wall (15, 15 ', 15 ") formed in the disc (3) between the grooves (9), for counteracting depression of the outwardly facing side (5) within the region of the bottom (17) of the groove (9) when the wood chipboard (1) is subjected to stress, wherein the groove (9) in its cross section across its longitudinal direction is formed with an arcuate shape. (Figure 1)

Description

534 587 For example, US 4,702,870 discloses a method of making a board of wood fibers comprising cavities.

It is further desirable to provide a lightweight wood chipboard having high strength and which is not time consuming to manufacture.

It is also desirable to provide a lightweight wood chipboard, which is constructed to be able to prevent a screw from being easily pulled out.

It is also desirable to provide a wood chipboard manufacturing apparatus which can manufacture a lightweight wood chipboard, exhibiting high strength, having high production capacity during short production cycles and cost effective.

It is further desirable to further develop known wood chipboard to be able to use these in the furniture industry which requires strong and light wood chipboard. Serial production of furniture also requires cost-effective production of wood chipboard that is refined into furniture.

SUMMARY OF THE INVENTION This has been solved by the wood chipboard defined in the introduction having the features stated in the characterizing part of claim 1.

In this way, the wood chipboard can be light and at the same time strong and withstand point loads on the outward-facing side of the wood chipboard. By creating base foundations with gluing surface in combination with the arch shape of the groove creating support walls with as large a load-bearing capacity as possible, a smaller amount of material can be used while the wood chipboard can be made thin enough to be used in the furniture industry.

Preferably, the arch shape has a constant radius. 10 15 20 25 30 534 587 This gives an optimal strength for a light wood chipboard.

Preferably, the width of the base foundation is 3-7 mm in the direction transverse to the longitudinal direction of the grooves depending on the radius of the arch vault and the thickness of the wood chipboard. Suitably then the radius R of the wall surface of the arch vault is 5-7 mm and the thickness of the wood chipboard is 16-22 mm.

Alternatively, the grooves are formed at the two inwardly facing sides and are arranged facing each other.

Thereby the wood chipboard can be easily achieved where the base foundations of the respective board and the support walls of each board cooperate by the base foundations being glued to each other for support and the arched shape of the grooves of each board provides optimal strength for supporting the outwardly facing side within the channel area.

Preferably, a bore is provided between two adjacent grooves in a disc, extending from the outwardly facing side through the adhesive surface to reinforce the grip of a fastener.

In this way, the adhesive surface, which primarily acts as a base foundation, can also be used for reinforcing the materials of the wood chipboard bit into the wood chipboard for tightening, for example, a screw. It is desirable that this reinforcement for tightening the screw is satisfactory because often wood chipboard instead of glued together is screwed together by the user after purchase to form furniture.

Alternatively, the wood chipboard is a furniture component.

Thus, a piece of furniture can be made light and at the same time strong and made to be cost-effective to manufacture. This has also been solved by the wood chipboard manufacturing device the features set out in the introduction indicated in the characterizing part of claim 5.

In this way, a cost-effective manufacture of a light and strong wood chipboard has been achieved.

Preferably, the elongate projections are designed in such a way that the arcuate shape has a constant radius.

Thus, the projection of the press pad can contribute to an optimal distribution of glued wood chips around the projections before the pre-pressing. Alternatively, the turning means comprises a gluing means for applying glue to the adhesive surfaces of the first and second pre-pressed board.

In this way, production can be automated with the help of robots, which is cost-effective.

Preferably, the forming surface comprises a peripheral frame forming surface flush with the adhesive surfaces.

Thus, a board for gluing together with another board has been formed, which together with the glued board forms the wood chipboard, which can be cut in a suitable dimension from a modular system where the frame forming surface after cutting has a homogeneous end edge without groove openings. Furniture that is manufactured in series usually has certain given dimensions and the modular system is suitably adapted to such series dimensions where the cut ends up within the area of the framing surface. 10 15 20 25 30 534 587 SUMMARY OF THE FIGURE In the following, the invention will be described as examples of embodiments with reference to the accompanying drawings, in which schematically: Figure 1 shows a cross section through a wood chipboard according to a first embodiment; Figure 2 shows how thin material dimensions can be achieved by arcuate shape; Figures 3a-3b show in more detail an arcuate shape; Figures 4a-4e show a spreading device in a wood chipboard manufacturing device; Figure 5 shows str your spreading devices at a clock press; Figures 6a-6b show a clock press of the wood chipboard manufacturing apparatus; and Figures 7a-7b show a turning means.

PREFERRED EMBODIMENTS The invention will now be described as exemplary embodiments. For the sake of clarity, details without significance to the invention have been omitted from the drawing.

Figure 1 shows a cross section through a wood chipboard 1 according to a first embodiment. The wood chipboard 1 is made up of two glued boards 3. Each board 3 comprises an outwardly facing side 5 and an inwardly facing side 7.

The inverted sides 7 of the respective disc 3 face each other.

Each disc 3 has grooves 9 recessed on the inwardly facing side 7. The grooves 9 form parallel channels in the wood chipboard 1. Between the grooves 9 within the area for gluing the boards 3 there is an adhesive surface 11, i.e. between the boards 3 in the position between the grooves 9. 15 20 25 30 534 587 6 The wood chipboard 1 surface 11 between two adjacent grooves 9 of a board 3 forms the base foundation 13 for a support wall 15. The support wall 15 is formed of glued wood chips located between the grooves 9. Each board 3 thus has a number of support walls 15, 15 ', 15 "etc. which support the respective outwardly facing side 5. In figure 1 the base foundations 13 for the respective support wall 15 of the opposite boards 3 are glued together and rest against each other in the wood chipboard 1. The support walls 15 between the grooves 9 counteract the indentation of the outwardly facing side 5 within the area of the bottom 17 of the groove 9 when the wood chipboard 1 is subjected to stress, which can be stress in the form of both bending and point loading. going direction in the disc 3 is formed with an arcuate arch shape, an optimum load-bearing capacity and strength of the support wall 15 is achieved cooperating with adjacent support walls 15 ', 15 ". Figure 1 shows a bore 19 arranged between two adjacent grooves 9 in a disc 3. The bore 19 extends from the outwardly facing side 5 through the adhesive surface 11 into the second disc 3. When a fastening element, such as a screw 21, is screwed into the wood chipboard 1 the threads of the screw 21 are firmly attached to the cured adhesive surface 11 comprising cured adhesive. This strengthens the grip of the screw 21 in the wood chipboard 1, which is important in furniture made of wood chipboard 1. In Figure 1, the adhesive surface 11 'within the area of the bore 19 is wider than other adhesive surfaces 11 where no fastening element is needed for building a piece of furniture (not shown). ).

The arcuate shape shown in Figure 1 has a curvature with a radius R which is constant.

Figure 2 shows in more detail the direction of the forces supporting the outwardly facing side 5 in the support walls 15, 15 'around a groove 9. The two support walls 15, 15' formed with the arch shape have a groove wall surface 23 which has a curvature of the radius R by 7 mm. The thickness of the board 3 is 9 mm, which gives a wooden chipboard 1 with a total thickness T of 18 mm, which is a standard thickness for series-produced furniture, such as cabinets and benches. The dimension between the outwardly facing side 5 of the board 3 and the “roof” (bottom 17) can thus be as thin as 2 10 15 20 25 30 534 587 mm, at the same time as the wood chipboard 1 can show good strength and can be of low weight. This is shown at S in Figure 2.

The distance A between two grooves 9 or the width of the base foundation 13 3lim surface 11 is here 4 mm. The CIO dimension is thus 18 mm for the wood chipboard 1 shown in Figure 3. A force F acting on the outwardly facing side 5 is counteracted by the abutting forces f created by the arch vault.

The wood chips (not shown) that make up the wood chipboard 1 have a chip size. which is less than about 2-3 mm. Approximately half of the wood chips in the wood chipboard have a chip size of less than 1 mm, which is advantageous for building up the grooves 9 with an arcuate shape. The arcuate-shaped groove wall surface 23 takes advantage of being as fine as possible to avoid sharp breaks in the arcuate surface. Such interruptions could affect the strength and load-bearing capacity of the wood chipboard 1. The smaller clamping size of less than 1 mm also allows it to be easier to compress the wood chips as a whole during the pre-compression manufacturing process. That is, the finer material of the wood chipboard 1 at the same time gives a fine surface of the arch shape and provides easier compression molding for manufacture. Most wood shavings of the other wood shavings, than those under 1 mm, are wood shavings that are between 1-2 mm.

Figure 3a shows on an enlarged scale the section of the wood chipboard 1 in Figure 2. The radius R closest to the base foundation 13 and the adhesive surface 11 supporting the respective outwardly facing side 5 is here 5 mm. In this wood chipboard 1, outer layers 25 comprising wood chips 27 with a longitudinal extent (2-5 mm) have also been provided. These longer wood chips 27 have an orientation with their longitudinal fiber direction substantially transverse to the longitudinal direction of the grooves 9. In this way, the wood chipboard 1 is further reinforced against bending. Fig. 3b is shown closer to the force majeure supporting the outwardly facing side 5 in the support walls 15 around a groove 9 shown in Fig. 2. A force F acting on the outwardly facing side 5 within the area of the groove 9 is counteracted by the restraining forces created by the arch shape.

Figures 4a-4e show a spreading device 35 in a wood chipboard rewinding device 37. An dispenser 39 and a lower press pad 41 (or so-called spreading pad) move relative to each other in such a way that the dispenser 39 discharges glued wood chips 43 on the lower press pad 41. The the lower press pad 41 moves relative to the dispenser 39 (see Figure 4b) and a chip mat 45 is formed on the lower press pad 41. Thereafter, a flow template 47 (chip distributor), provided with slots 49, is positioned above the chip mat 45. The dispenser 39 is now moved over the flow template 47 and discharges glued wood chips thereon, wherein the wood chips are distributed through the slots 49 and fall down on the chip mat 45 forming strands 51, as shown in Figures 4c and 4e. A chip mat 45 of varying thickness has been created with strands 51, which chip mat is now ready for compression molding. The chip mat 45 applied to the lower press pad 41 is defined as an insert with reference numeral x.

A number of inserts x ', x ", x'" ... x "are completed in the said manner by means of a plurality of spreading devices 35 or spreading stations and are inserted simultaneously in compartments 53 of a compression molding member 55 included in the wood chipboard manufacturing device 37. This saves time. and the production becomes cost-effective See the schematic representation in Figure 5. The compression means 55 is a so-called clock press (see Figure 5a). each compartment 53 also comprises an upper press pad 57. Heat is created by means of heating means (not shown) and the bar press drives an upper press tool 59 which acts on the upper press pads 57 in movement towards the lower press pads 41 comprising respective chip mat 45. The upper press pad 57 comprises a forming surface 61 comprising elongate parallel projections 63 with flat surfaces 65 therebetween for forming adhesive surfaces 11 (see Figure 7b) of the discs 3 for joining.

Each projection 63 is formed in its cross section across its longitudinal direction with a curvature for forming grooves 9 in the disc 3 with an arcuate shape. The chip mats 45 are compressed under heat and the discs 3 are formed and begin a curing process.

The discs 3 are discharged from the compression means 55 after the forming of the discs 3 and cool to a part. The wood chips (not shown) of the boards 3 have a chip size of less than about 2-3 mm. Approximately half of the wood chips in the wood chipboard have a chip size that is less than 1 mm, which is advantageous for building up the grooves with an arched shape. The wall 23 with arch shape takes advantage of being as fine as possible to avoid sharp breaks in the arch surface. Such interruptions could affect the strength and bearing capacity of the wood chipboard 1. The smaller chip size below 1 mm also allows it to be easier to compress the wood chips in their entirety during compression molding. That is, the finer material of the disc 3 at the same time gives a fine surface of the arch shape and provides easier compression molding for manufacture. Most wood shavings of the other wood shavings, than those under 1 mm, are wood shavings that are between 1-2 mm.

Figures 7a-7b show a turning member 67 in the form of a robot 69. The robot 69 comprises a robot arm 71, which turns the pre-pressed discs 3 towards each other after applying glue to the adhesive surfaces 11 of the discs and lays one disc 3 with its inwardly facing side 7 downwards. against the opposite board 3 forming the wood chipboard 1, which is shown in figure 7b. Before turning, the discs 3 are discharged from the clock press. A discharge device (not shown) for discharging the respective molded disc comprises ejectors (not shown) projecting the respective disc 3. The turning means 67 comprises a gluing means 66 for applying glue to the adhesive surfaces 11 of the first and second molded disc 3. The finished light and the strong wood chipboard 1 in figure 9b has a weight of approximately 400 kg / cubic meter.

The present invention should not be construed as limited by the described embodiments, but variations and combinations of the illustrated examples or other examples within the scope of the appended claims may be 534 587. Different types of glue can be used. such as PVAC, UF, phenol, hot melt adhesive or carpentry adhesive.

Claims (7)

10 15 20 25 30 534 587 11 Wood chipboard made up of two glued boards (3), each comprising an outwardly facing (5) and an inwardly facing side (7), recessed grooves (9) of at least one inwardly facing side (7) form parallel channels (k) in the wood chipboard (1 ), and an adhesive surface (11) between the discs (3) in the position between the grooves (9), the adhesive surface (11) between two adjacent grooves (9) in a disc (3) constitutes a base foundation (13) for one in the disc (3) between the grooves (9) formed support wall (15, 15 ', 15 "), for counteracting depression of the outwardly facing side (5) within the area of the bottom (17) of the groove (9) when the wood chipboard (1) is subjected to stress, wherein the groove (9) in its cross section transverse to its longitudinal direction is formed with an arcuate shape, characterized in that the arcuate shape has a constant radius (R), wherein the support wall (15, 15 ', 15 ") has a groove wall surface (23) with the radius (R) and is formed with an arched shape. 2.. Wood chipboard according to claim 1, wherein the grooves (9) are formed at the two inwardly facing sides (7) and are arranged facing each other. Wood chipboard according to claim 1 or 2, wherein a bore (19) is arranged between two adjacent grooves (9) in a board (3), extending from the outwardly facing side (5) through the adhesive surface (1 1) for reinforcing a screw ( 21) grip in the wood chipboard (1) in that when the screw (21) is screwed into the wood chipboard (1), the screw (21) gets fixed in the hardened adhesive surface (11). 3.. Wood chipboard according to one of the preceding claims, wherein the wood chipboard (1) is a furniture component. 4.. Wood chipboard manufacturing apparatus comprising 534 587 12 a bar press (55) arranged for vertical movement comprising a plurality of compartments (53) arranged one above the other, a plurality of upper (57) and lower (41) press pads insertable in the compartments (53), - a spreading station (35) comprising a wood chip dispensing device (39) for discharging glued wood chips constructing a chip mat (45) of varying thickness on the respective lower press pad (41) by means of an associated chip distributor (47) before insertion into the compartments (53), discharge of respective molded disc (3), characterized in that the upper pressing pad (57) comprises a forming surface (61) comprising elongate parallel projections (63) with flat surfaces (65) therebetween for forming adhesive surfaces (11) of the disc (3). ), which projections (63) are each formed in their cross-section across their longitudinal direction with a curvature for forming grooves (9) in the disc (3) with an arcuate shape, wherein the discharge device comprises a v end means (67) for turning and gluing the molded disc (3) against a second disc, wherein they The elongate projections (63) are designed in such a way that the arch shape has a constant radius (R). Wood chipboard manufacturing device according to claim 5, wherein the turning means (67) comprises a gluing means (66) for applying glue to the gluing surfaces (11) of the first and second molded board. Wood chipboard manufacturing device according to any one of claims 5 to 6, wherein the forming surface (61) comprises a peripheral frame forming surface (31) flush with the adhesive surfaces (11).