WO2011082797A1

WO2011082797A1 - Method and dispersion head for producing a particle material mat made of at least one layer that is dispersed in an oriented manner as part of the production of wood composite boards

Info

Publication number: WO2011082797A1
Application number: PCT/EP2010/007717
Authority: WO
Inventors: Gernot Von Haas
Original assignee: Dieffenbacher Gmbh + Co. Kg
Priority date: 2009-12-16
Filing date: 2010-12-16
Publication date: 2011-07-14
Also published as: CN102883862B; CN102883862A; DE102009054807A1

Abstract

The invention relates to a method and to a dispersion head for producing a particle material mat (7) made of at least one layer, which is dispersed in an oriented manner and made of orientable particle material (9), on a continuously revolving moulding belt (8) by means of at least one dispersion head (1), wherein the particle material (9) is introduced into the dispersion head (1) substantially in the dropping direction (19) via a particle material chute (17) and is transferred by means of at least one guiding device (5) to a transverse orientation device (12). The particle material (9) is deposited on the moulding belt by means of the transverse orientation device (12) transversely to the production direction (15), wherein the transverse orientation device (12) consists of at least one rotatably driven flap roller (6) mounted horizontally and transversely to the production direction (15), wherein the flaps (11) pass over an angle of 0° to 360° during the rotation about the axis of the flap roller, wherein the 0° position is passed by the flaps (11) when the flap ends (20) thereof are located the furthest from the moulding belt (8). The invention is characterized in that the dispersion of the particle material (9) by the guiding device (5) onto the flaps (11) of the flap rollers (6) is carried out substantially in a charging region (21) with the flaps (11) being in a position of 270° to 360° (1398).

Description

Method and scattering head for producing a grit mat from at least one oriented scattered layer in the course of the production of

The invention relates to a method for producing a spreading material mat from at least one oriented layer in the course of the production of wood-based panels according to the preamble of claim 1 and a scattering head for producing a spreading material from at least one oriented layer in the course of the production of wood-based panels according to the preamble of claim 7.

In the production of material plates from scatterable materials, a mixture of particles or fibrous materials and a binder is scattered to a grit mat on a forming or conveyor belt, the grit mat then a possibly necessary pre-treatment and

finally fed to a compression. In this case, usually discontinuous floor presses and continuously operating presses are used, wherein in the latter between two rotating steel belts a scattered pressed material mat is pressed with glued scattering particles under pressure and heat input. In addition to pure particle boards (MDF), chipboard wood chips are also used, which are usually spread in an oriented manner in order to increase the strength and strength of the wooden boards produced in their length and width. It will be Types of fabrication differed for oriented scattered plates in the longitudinal and transverse direction (OSB) and in the orientation purely in the longitudinal direction (OSL). Usually, such OSB and OSL boards are produced on continuous double belt presses with densities of up to 750 kg / m ³ .

Experiments with different pressing methods in double belt presses to increase the densities to more than 750 kg / m ³ , have been essentially unsuccessful, since the still warm plates burst after leaving the press or subject to excessive springback, so that the plate thickness strong increases, causing the plate density drops significantly again.

Of far-reaching economic importance is now the desire for high-density oriented chipboard in the container industry for ship, storage, office or residential containers. A requirement of the Chinese industry for container plates prescribes a bending strength of 69 N / mm ² at a bearing distance of 250 mm for 28 mm thick container floors. The European industry writes in comparison to the examination of the

Bending strength before higher bearing distances, which also higher

Lead bending strengths. However, the smaller bearing distance of 250 mm leads to very high shear stresses in the neutral fiber of the plate during the bending test. Therefore, plywood panels with densities of around 900 kg / m ³ have hitherto been used predominantly as panels for container floors. In addition to the high bending strength, the plate surface has a have sufficient hardness and sufficient abrasion resistance. In addition, the load, by means of a wheel, for example, of one

Forklift, is applied to the plate, sufficient in the plate longitudinally and transversely to the wheel on the supports of the metal grooves on

Containerboden be distributed.

Due to these high requirements, it has not been possible to produce a slab of long chips or chips which is the basis of the

Requirements of container construction is sufficient.

Besides the possibilities the process parameters (temperature,

Verdichtungsgrad, temporal processes, adhesives) during the

It has been found that the quality of the scattering in all material-oriented oriented material plates has a high degree of importance, in particular to produce high-density plates. In addition to the dense as possible pressing, it is a further need in particular to use long chips or chips to the

Bending strength of such plates, be it simple OSB boards or for special applications (container construction), significantly increase. Long

However, chips are susceptible to breakage during the scattering due to the necessary machine elements in a scattering head, so that

preferably a gentle dispersion should be sought. Furthermore, the following specifications are made for the scattering rollers or the fan rollers. Fan rollers for the transverse orientation of the chips or the scattering material have a transverse to the forming belt direction and horizontally oriented roller on which a plurality of compartments are arranged. During rotation, a fan passes through a circle and thus covers an angle from 0 ° to 360 °. It is determined that the 0 ° position (= 360 ° position) is passed through when the fan or the fan end in the vertical upward and thus perpendicular to the forming belt and furthest away, so that the roller between the forming belt and the fan is arranged. Accordingly, the 180 ° position is located at the position at which the fan end of a fan of all compartments closest to the forming belt is located. Thus, in a left or right rotating arrangement, the position of a fan between 0 ° and 180 ° always in the descending branch of the rotation and the position of a fan between 180 ° and 360 ° always arranged in the ascending branch of the rotation.

According to the previously known methods, the spreading material is randomly applied to the fan rollers for transverse orientation, so that the ascending and descending branches are fed uniformly. This has not been found to be effective, so that it is documented in the prior art that baffles or guiding devices, the chips or chips

preferably in the descending branch (0 ° to 90 °) on the fan rollers give up. For example, EP 0 860 254 A1 has disclosed a method and a device for scattering a multi-layer spreading material mat. In this case, scattering rollers are arranged, which are fed by means of baffles and deposit the spreading material on the forming belt. The grit is applied as already stated predominantly in the descending branch of the rotating spreader rolls by means of the baffles. At the same time, the orientation space between the compartments of the scattering rollers is externally by means of another

Guide plates narrowed. A transverse orientation of long chips would be conceivable with such an arrangement, but it would be an unspecified fraction of the chips by the plurality of

Device elements damaged, since directly after the introduction of the chips in the orientation rollers, the orientation spaces are covered and thus shearing edges are installed, which can shave long chips.

DE 297 07 143 U1 discloses a device for aligning and depositing elongate parts such as wood chips, wood fibers or the like on a continuously moving base. This disclosure again shows baffles which transfer the spreading material to be oriented with a certain primary orientation to the transverse orienting spreading rollers. In this case, have the cross-oriented fan rollers

air-impermeable compartments on whose ends bends or kinks are arranged. The disclosure essentially teaches this in

Connection with Figure 1 of DE 297 07 143 U1, that these special subjects a retention effect for the grit in the descending branch and that the fan rollers are fed by vertically inclined baffles which ensure that the

Fan rollers targeted in their upper area, where the subjects open to the opening rollers to be charged. Further information on the area of the opening is dispensed with, which does not give the skilled person any clear teaching about the preferred task point or range for the chips. FIG. 1 of DE 297 07 143 U1 shows that the charging is started essentially at the moment when the compartments of the

Fan roller crossing the vertical. Due to the bend of the

Fächerenden open the fan rollers really properly against the overlying opening rollers when the 0 ° passage

is passed.

Experiments and the present experience in the scattering technique have shown, however, that such an arrangement allows a sufficiently effective and accurate scattering only with a small amount of charge and in particular with short chips.

The invention has for its object a method for producing a relation to an endlessly rotating forming belt transversely oriented

Grit mat or at least one transverse oriented layer of a

To provide grit mat, in which the scatter quality compared to the prior art significantly improved and the scatter itself significantly gentler can be carried out for the grit. In particular, this applies to grit of a length of about 180 mm, preferably over 220 mm, more preferably for grit a length of 250 to 300 mm and more.

This object is achieved by the invention for the method in that the

Task of the material to be spread by the guide on the subjects of

Fächerwalzen essentially in a task area with position of the compartments of 270 ° to 360 ° is performed.

The solution for a spreading head is that the task area for the spreading material is arranged by the guide device substantially at the position of the compartments of 270 ° to 360 °. Advantageously, now the chips or grit can be gently introduced into the fan rollers, because the grit has by the early task in the fan rollers, already in the ascending branch, enough time to put oriented in the fan rollers into, so that essentially when passing through the 0 ° -Positin the subjects already the majority of the material to be spread is oriented transversely. This makes it possible that during the stay in the orientation area in the descending branch of

Rotation (0 ° to 180 °) already a pre-orientation of the grit mutually developed, so that the grit already optimally to each other can be stored on the form band. For this reason, the forming belt should also be transported in the same production direction in which the trays rotate or move when passing through the 180 ° position. A further advantage is that orientation errors are avoided and damage is prevented by spreading out of the fan rollers scattering material on the material itself. An unoriented chip or chip, which is almost perpendicular and not oriented transversely, is broken off, for example, upon contact of an adjacent roll, a guide device and / or when placed on the forming belt. Even if it is not broken, so usually kinks and thus scattering errors in the

Spreading mat, since the grit can no longer invest optimally in this area due to a kinked chip or chip to produce an optimally scattered grit mat. Incidentally, an orientable spreading material is distinguished by the fact that it has at least a significant length, which is greater than the other two dimensions (width and thickness) and with which the spreading material can be oriented at all. Of course, there is still a more or less large proportion of non-orientable spreading material in the orientable spreading material, which is present due to production.

The scattering head is self-contained in its own right and can not stand alone for carrying out the method with the described features be used. At the same time, the spreading head is also suitable in particular for carrying out the method according to claim 1.

In particular, it is now possible to use oversized chips or chips with a length of over 180 mm as a grit and to shape both gently and in optimized form as a layer on a forming belt to a grit mat, when essentially with the task of the material to be spread on the subjects The fan rollers are started while the fans pass through the angle of 270 ° to 360 °. Preferably, for this purpose, the distance between the fan rollers is carried out very far, which increases the space for several fan rollers in series (in the production direction) significantly. It may also make sense in relation to a compact space to start with the feeding of the fan rollers at 300 °, or even at 330 °.

Preferably, the guide device consists of baffles and arranged thereon sliding surfaces for the grit that the grit in

Passing task of the fan rollers. Even with the gentlest possible treatment of the material to be spread, it may be necessary that the material to be spread after entering the scattering head by means of at least one

Opening device is dissolved with at least one opening roller.

Particularly preferred rotate the fan rollers of

Transverse orientation device during the passage through the 180 ° - position in the production direction of the forming belt, preferably the Fan rollers are operated at a peripheral speed at the fan ends of the fan, which corresponds to 50% to 100% of the speed of the forming belt.

In order to introduce as much grit in the task area in the fan rollers, it may be useful to arrange at least one scraper at the guide device substantially in the vicinity of the 0 ° position.

Preferably, the scraper is so flexible that damage to the grit are avoided. Particularly preferably, the fan ends of the compartments have a distance between the fan ends of 80% to 120% of the length of the material to be spread. The compartments should preferably have a length between 50% and 100% of the length of the grit 9.

With regard to the guide device, it is advantageous when using guide plates if at least one means for preorienting and / or influencing the orientation of the material to be spread is arranged on the guide plates. Such a resource could be surveys. Preferably, the

Elevations in their longitudinal extent substantially angled to

Fall direction and / or sliding direction of the material to be spread are arranged. The elevations are, for example, strips or the like and preferably designed in an elongated continuous shape. Preferably, the elevations have a height of less than 25 mm, preferably less than 20 mm.

They should also be arranged with a distance of 100% to 120% relative to the length of the material to be spread. The sliding surface of

Guide device should with the direction of the scattering material substantially with an angle between 0 and 45 °, preferably less than 30 °, be arranged. This steep angle is necessary with it

Further advantageous measures and embodiments of the subject matter of the invention will become apparent from the subclaims and the following

Description with the drawing out.

Show it:

Figure 1 is a schematic representation of a scattering head with a promotional from right to left mold band and two different geometrically different guide devices for the task of the material to be spread on the fan rollers of

Transverse orientation device

Figure 2 shows another variant of a possible guide device according to FIG

1 ,

Figure 3 is a highlighted representation of the distance between two

Fan rollers of a transverse orientation device,

Figure 4 shows a possible particular embodiment of a baffle of a

Guide device with surveys for pre-orientation of the material to be spread shortly before the transfer to the

Transverse orientation device

Figure 5 is an enlarged view through the cross section of a

Fan roller of the transverse orientation device, FIG. 6 is a schematic representation of the possible angular positions and of the feeding area of the material to be spread on the basis of a cross-section of a clockwise-rotating fan roller;

Figure 7 is a schematic representation of the possible angular positions and the task area of the grit with reference to a

Cross-section of a left-rotating fan roller and

Figure 8 is a schematic representation of the possible angular positions at a reduced application range of 300 ° to 360 ° in a right-handed fan roller.

Figures 1 and 2 show a schematic representation of a

Litter head 1 with a promotional from right to left mold belt 8 and several different geometrically different guide devices 5 for the purpose of the scattering material 9 on the fan rollers 6 of

Transverse orientation device 12. In this case, the grit 9 from a supply device (not shown), for example a

Grit bunker or a metering device for a uniform discharge into the scattering head 1 in the direction of fall 19 introduced into the grit task 17 of the housing 3 of the scattering head 1. Preferably, after entry of the material to be spread 9 in the spreading head 1, the spreading material 9 by means of a

Dissolved dissolving device 4 and evenly distributed in the spreading head 1. The opening device 4 may consist of one or more opening rollers 2, which are preferably designed as rollers with spikes 14. After the optional resolution, the grit still falls unoriented on the guide 5, which brings together the grit 9 and uniformly passes in a predetermined range of the fan rollers 6 for transverse orientation. The guide device 5 can have means for preorientation (FIG. 4).

According to the teaching of the invention is essentially started with the task of the material to be spread 9 on the subjects 11 of the fan rollers 6, when the subjects 11 pass through the angle of 270 ° to 360 °. When several fan rollers 6, as shown in Figures 1 and 2, a plurality of baffles 10 are arranged as a guide 5 side by side.

Figure 1 shows on the left side of the scattering head 1 baffles in a triangular embodiment, with at least one surface side, which is designed as a sliding surface 26 and is arranged at an angle to the vertical. On the sliding surface 26 of the baffles 10, the spreading material is guided in the direction of the feed area and transferred to the fan rollers 6. Opposite the left three baffles 10, the right three baffles 10 at a more acute angle with respect to the vertical for the sliding surface 26. After the spreading material 9 comes to rest in the orientation space 13 between the compartments 11 of the fan rollers 6, the fan rollers 6 transport the spreading material in the direction of the forming belt 8 and deposit it in the direction of fall 19. During the 180 ° passage, when a fan end 20 of a fan 11 is perpendicular to the forming belt 8, the speed vector of the fan end 20 points in the same direction as the transport direction of the forming belt 8, In FIG. 2, essentially the same scattering head 1 is shown, wherein the preferably triangular guide plates 10 have an additional scraper 18, which is arranged such that the essential main part of the chips respectively of the scattering material 9 is in the range between 300 ° and 360 °, based on the right-handed fan rollers 6 (at a zero crossing in the upper vertical orientation of the compartments 11) enters the orientation space 13 of the fan rollers 6. The scrapers 18 are preferably flexible or resilient so that they do not destroy the grit 9 with greater resistance by the grit 9, but yield.

FIG. 3 shows the distance between the fan rollers 6, which adjusts when two compartments 11 lie in one plane and the fan ends 20 face one another. In this example, the baffle 10 is arranged so that a task of the grit 9 in a task range of 270 ° to 360 °, ie in the ascending part of the fan roller 6, is possible. For this purpose, however, the distance between the fan rollers 6 and the fan ends 20 to each other larger, to the guide 5 and the baffle 10th

Opportunity to reach the corresponding task area 21.

Figure 4 shows a possible particular embodiment of a baffle 10 of a guide 5 with elevations 24 for preorientation of

Grit 9 before transfer to the transverse orientation device 12 The elevations 24 are preferably elongated and are at an angle to the direction of fall 19 respectively

Sliding direction of the grit 9 arranged on the sliding surface 26 to give the grit 9 in its longitudinal extent a certain pre-orientation, so that the grit 9 between the compartments 11 can find its oriented position easier.

FIG. 5 graphically represents the length 22 of the compartments 11 and the distance 23 between two compartments 20 for the above-mentioned design rules. The dimensioning arrow for the distance 23 also illustrates the size of an orientation space 13 between two compartments 11.

FIGS. 6 to 8 show various task areas 21 and

In particular, the degrees described during one revolution of a fan roller 6 illustrates. If the fan end 20 is farthest from the forming belt 8, then the fan 11 of said fan end 20 is in the 0 ° position. In Figure 6 is a clockwise

Fan roller 6, shown in Figure 7, a left-rotating fan roller 6. Common to both is that while the fan is moving from the 0 ° position in the falling direction 19, the fan 11 sweeps the peripheral area (0 to 360 °) from 0 ° to 180 ° and thus moves on the descending branch. After passing through the 180 ° position, when the

Fächerende 20 is directed perpendicular to the forming belt 8, is the Fan in the ascending branch. The task area 21 for the grit is located after 6 in a right-handed fan roller 6 on the left side, while the task area in a left-handed

Fan roller 6 is arranged on the right side, but also in the ascending branch.

Figure 8 shows a shortened task area for a small distance 15 between two fan rollers 6 of only 300 ° to 360 0 °. Depending on

Mass flow rate, size of the material to be spread in the longitudinal direction and other parameters, it may be useful the fan roller 6 in their distance 16 to each other by means of an adjusting device (not shown) to arrange adjustable to each other. Also, the guide device 5 may be arranged in its position, position, orientation, nature, size and other parameters adjustable to depending on the scattering material to be scattered

To be able to set the spreading head to different spreading material parameters. 1398

List of numbers 1398:

Scattered head 14. sting from 2

Opening rollers 15. Production direction

Housing 16. Distance from each other 6 Dissolving device 17. Grit task of 1

Scattering device 18. scraper

Fan roller (transverse orientation) 19. Fall direction

Spreading mat 20. Filling end

Formband 21. Task area

Grit 22. Length of the compartments 11

, Baffle 23. Distance between two fan ends. Subjects 24. Surveys

, Transverse orientation device 25. Distance between two elevations 24. Orientation space 26. Sliding surface

Claims

claims

Method for producing a spreading material mat (7) from at least one oriented scattered layer of orientable spreading material (9) on an endlessly circulating forming belt (8) by means of at least one spreading head (1), wherein the spreading material (9) extends substantially in the falling direction (19) a grit feed (17) is introduced into the spreading head (1) and transferred by means of at least one guide device (5) on a transverse orientation device (12) and by means of the transverse orientation device (12) the spreading material (9) placed on the forming belt transversely to the production direction (15) is, wherein the transverse orientation device (12) consists of at least one rotatably driven, horizontally and transversely to the production direction (15) mounted fan roller (6) whose fan (11) during rotation about the axis of the fan roller an angle of 0 ° to 360 ° paint over, with the

0 ° position is passed through the compartments (11), when the fan end (20) of the forming belt (8) is the farthest, d a d u r c h e c e n e c e s in that e

the task of the scattering material (9) by the guide device (5) on the subjects (11) of the fan rollers (6) substantially in one

Task area (21) with position of the compartments (11) of 270 ° to 360 ° is performed. A method according to claim 1, characterized in that substantially with the task of the scattering material (9) on the compartments (11) is started when the subjects (11) pass through the angle of 300 °, in particular the angle of 330 °.

Process according to claims 1 or 2, characterized

characterized in that the guide device (5) passes the spreading material (9) to the fan rollers (6) by means of guide plates (10) and sliding surfaces (26) arranged thereon.

Method according to one or more of the preceding

Claims, characterized in that the

Spreading material (9) after entering the scattering head by means of at least one opening device (4) with at least one opening roller (2) is dissolved.

Method according to one or more of the preceding

Claims, characterized in that the

Rotate fan rollers (6) of the transverse orientation device (12) during the passage through the 180 ° position in the production direction (15) of the forming belt (8). Method according to one or more of the preceding

Claims, characterized in that the

Fan rollers (6) with a peripheral speed at the

Fächerenden (19) of the compartments (11) are operated, which corresponds to 50% to 100% of the speed of the forming belt (8).

Scattering head for producing a spreading material mat (7) from at least one oriented scattered layer of orientable spreading material (9) on an endlessly circulating forming belt (8) by means of at least one scattering head (1), wherein in the direction of fall (19) for the introduction of the grit (9) in the scattering head (1) a grit task (17), at least one guide device (5) for transferring the material to be spread (9) on a transverse orientation device (12) and the transverse to

At least one transverse orientation device (12) is arranged, at least one rotatably driven and horizontally mounted fan roller (6) having a plurality of compartments (11) being arranged as a transverse orientation device (12) and being rotated during the rotation the axis of the fan roller (6) sweeps the compartments (11) at an angle of 0 ° to 360 °, wherein the 0 ° position is defined by the compartments (11) as the position when the fan ends (20) from the forming belt (8 ) are furthest away, characterized in that the task area (21) for the grit (9) by the guide device (5) is arranged substantially at the position of the compartments (11) of 270 ° to 360 °.

8. spreading head according to claim 7, characterized in that at least one opening device (4) for the dissolution of

Scrap material (9) between the grit task (17) and the

Transverse orientation device (12) is arranged.

9. spreading head according to claim 8 or 8, characterized

characterized in that guide plates (10) are arranged as the guide device (5).

10. spreading head according to one or more of claims 7 to 9,

characterized in that on the guide device (5) at least one scraper (18) substantially in the vicinity of the

0 ° position is arranged.

11. spreading head according to one or more of claims 7 to 10,

characterized in that fan ends (20) of the compartments (11) with a distance (23) between the fan ends

(20) of 80% to 120% of the length of the grit (9) are arranged.

12. spreading head according to one or more of claims 7 to 11, characterized in that compartments (11) having a length (22) between 50% and 100% of the length of the material to be spread (9) are arranged.

13. spreading head according to one or more of claims 7 to 12,

characterized in that at the guide plates (10) at least one means for preorientation and / or influencing the orientation of the material to be spread (9) is arranged.

14. spreading head according to one or more of claims 7 to 13,

characterized in that as means for

Preorientation on the baffles (10) surveys (24)

are arranged.

15. spreading head according to one or more of claims 7 to 14,

characterized in that the elevations (24) are arranged in their longitudinal extent substantially at an angle to the direction of fall and / or sliding of the material to be spread (9).

16. spreading head according to one or more of claims 7 to 15,

characterized in that the elevations (24) having a height of less than 25 mm, preferably less than 20 mm, arranged are.

Spreading head according to one or more of claims 7 to 16, characterized in that the elevations (24) are arranged at a distance from one another of 100% to 120% with respect to the length of the scattering material (9).

Spreading head according to one or more of claims 7 to 17, characterized in that the sliding surface (26) to the falling direction of the scattering material (9) is arranged substantially at an angle between 0 and 45 °, preferably less than 30 °.