EP1889702A2 - Method and apparatus for producing a solid or layered mat from granular substances - Google Patents

Abstract

Process for complete or layer-wise production of a mat from chips pressed by pressure and heat during the production of timber product plates comprises dispersing and sieving the chips using a roller bed and removing over-sized chips from the process, and exposing the remaining chips to a directed air flow followed by wind screening and a second sieving. The wind screening is performed using the air flow and a fine sieve. Over-sized chips undergo second sieving and any remaining over-sized chips are removed. The chips from the wind screening and the second sieving are used to make a mat or layers of a mat on a molded sheet. An independent claim is also included for a machine for complete or layer-wise production of a mat from chips pressed by pressure and heat during the production of timber product plates. Preferred Features: The second sieving is performed using a perforated sheet or wire net.

Description

The invention relates to a method for the complete or layered production of a grit mat from chips according to the preamble of claim 1 and a spreader for the complete or layered production of a grit mat from chips according to the preamble of claim 14.

Particleboard and the production of material plates from, for example, medium-density fibers are now automated processes and are already being used in many countries for many years. As in " Wood materials, production and processing "by Hansgert Soiné, DRW-Verlag 1995, pages 17ff described the compression of processed chips or fibers takes place either clock bound or continuously. In addition to the many plant components before and after the press, the production of a spreading material mat by means of spreading machines plays an outstanding role, since the quality of the produced spreading material mat is an important factor in addition to the quality of the raw materials.

For the large-scale production of wood-based panels, continuous presses are used. In these presses, as in DE 39 13 991 C2 described, the pressing force is transmitted by hydraulic actuators on the press and heating plates and further on steel belts, which are supported by a rolling element carpet (rolling rods) circumferentially arranged on the grit. In the case of the abovementioned transmission elements, the steel strips with thicknesses of approximately 1.5 to 4 mm form the weakest component in the chain of failure-threatening machine elements compared to the other, substantially stiffer elements. In this context, it does not mean that the steel strip fails completely, but should the surface of the steel strip damage it already leads to a regularly occurring poor quality of the final product and thus to rejects.
Due to the production of increasingly thinner and above all highly compressed wood-based panels, the deformation work to be performed increases with partial density differences of the material to be spread so much that even very small-scale density fluctuations, for example by fiber balls, glue lumps or oversized scattering pieces in the spreading material to pressure points on the surface of the steel strip or even lead to the destruction of the steel strip.
This circumstance has led to the plant manufacturers being forced to provide extensive protective measures for the continuously operating press or their steel strips to be produced. Examples are optical surface inspection, metal detectors, radiographic equipment, mechanical detectors for spreading material mats and much more. Such gauges have basically proven in the matter, but are problematic especially in fast-running systems, since at a production speed of more than one meter per second, the continuously operating press must be brought to a halt so quickly in an emergency or rapid shutdown that the density increase does not enter the press nip during the braking process and can cause damage to the steel belts there. In general, this succeeds successfully, but puts an enormous burden on the brake system and many machine elements of the continuous press, because in addition to the rotating steel belts, the massive idler pulleys, the revolving roll bar carpet and a few more machine elements are brought to a standstill with the corresponding moment of inertia have to. In addition, it is problematic that under certain circumstances the parallel operation of the rolling rods can no longer be guaranteed during an emergency stop. Such a situation can lead to fatal consequences and destruction when the press is restarted, so that the operator and the system manufacturer endeavors to avoid such a situation to the best of his ability. Furthermore, the global market for steels has increased in recent years by almost twice as much due to the increase in demand worldwide, and the trend continues to rise. Thus, the steel belts of a continuous press are the most expensive individual pieces of such Manufacturing plant and investments to avoid damage are therefore quite economically responsible.

In addition to the above already indicated possibilities to check the grit mat prior to entry into a continuous press on faulty or incorrect grit (glue lumps, metals, oversized grit and the like.) And thus protect the steel straps from a continuous press it is of course already conceivable intervene in the production process before and the production of the grit mat so to accomplish that no faulty grit can get into the grit mat.
For this purpose, it is the known prior art such as the DE 44 39 653 A1 or the EP 0 800 901 A1 to improve.
It can be seen from the patent literature that, for the spreading of glued chips, fibers or the like, the spreading material is applied to a plurality of spreading rollers driven in the same direction, which at least in groups have the same center distance and can thus assume a classifying function. For this purpose, it is also provided at the end of this scattering roller assembly to arrange a device that can eject erroneous grit from the grit stream from the scattering area. Furthermore, it is known in this case to subject the grit before or after the scattering rollers of an air flow parallel to the Formbandrichtung. Due to this air flow, small and fine particles of spreading material are carried far and thus first of all reach the forming belt to form a cover layer of fine particles. Larger and heavier spreading material is not so strongly influenced by the air flow and thus already reaches a carpet from the cover layer particles and thus forms the middle layer. To EP 0 800 901 A1 Now, such a scattering device can be arranged laterally reversed again, so that again a layer of heavier spreading material is applied to the already existing material of the spreading material mat and finally passes again a fine layer of cover layer particles on the now finished spreading material mat. Thus, a multi-layer grit mat can be produced by simple means having different layers, preferably fine particles form the outer layers and the larger and coarser material the middle layer. Both systems and methods have been proven in principle and were designed at a time when still predominantly calendering presses were used for the production of thin plates and the double belt presses were used with stainless steel bands for the production of thicker chipboard.

In recent years, the technology and the wishes of the producing wood-based panels industry has changed and a chipboard manufacturing plant must be able to manufacture over thick plates and thin plates in order to be competitive. However, the production of thin plates now requires an extremely controlled production of Grit mat, because faulty grit can lead to the already dealt with damage to the stainless steel bands.

1. a) im Luftstrom angeordnete Streuwalzen sind von Nachteil, da die übergeordnete Luftströmung dadurch behindert und unkontrollierbare Verwirbelungen auftreten. Gerade bei hohen Durchsätzen an Streugut führt dies zu einer schlechten Dichtenverteilung über die Länge und Breite der Streugutmatte und kann zu schädlichen Dichteüberhöhungen führen.
2. b) Bei Walzensieben kann es bei großen Durchsätzen unter Umständen vorkommen, dass zu viel Material aussortiert wird und eingestellte Durchsatzvorgaben an Streugut nicht realisiert werden.
3. c) Bei Walzensieben kann auftreten, dass zwischen den Walzen durchgedrücktes bzw. eingeklemmtes übergroßes Streugut die Walzen auseinanderdrückt und somit eine zu große Streugutmenge auf einmal und/oder übergroßes Streugut in Richtung Formband durchgelassen wird. Natürlich fällt bei dieser Gelegenheit auch das eingeklemmte übergroße Streugut in Richtung Formband.
4. d) Walzen- oder Rollensiebe klassieren nur nach einem Parameter (Walzenabstand = Dicke), zum Beispiel kann bei einem eingestellten Walzenabstand von 4 mm und einer Regelgröße des Streugutes von 12 mm × 8 mm × 3,8 mm immer noch ein übergroßes Streugutstück mit den Ausmaßen 25 mm × 10 mm × 3,5 mm durchfallen.

In the following points, the known state of the art has not proven:

1. a) arranged in the air flow scattering rollers are disadvantageous, since the superordinate flow of air thereby hindered and uncontrollable turbulence occur. Especially at high throughputs of grit, this leads to a poor density distribution over the length and width of the grit mat and can lead to harmful increases in density.
2. b) In the case of roller screens, it may happen that at high throughputs too much material is sorted out and set throughput specifications for spreading material are not realized.
3. c) In roller screens can occur that pressed between the rollers or pinched oversized grit forces apart the rollers and thus a too large amount of grit at a time and / or oversized grit is passed in the direction of the forming belt. Of course, on this occasion, the jammed oversized grit also falls in the direction of the forming belt.
4. d) roller or roller screens classify only according to one parameter (roller distance = thickness), for example, with a set roller distance of 4 mm and a controlled size of the material to be spread of 12 mm × 8 mm × 3.8 mm still fall through an oversized grit with the dimensions 25 mm × 10 mm × 3.5 mm.

The invention has for its object to provide a method and an apparatus for complete or layered production of a grit mat from chips, which ensures a sorting of oversized grit and / or glue lumps with the same outstanding outstanding quality over the length and width of the forming belt, so In the grit mat to be produced no density peaks with possible consequential damage to the press used can occur.

• 1.1 das Streugut wird einer Auflösung und Siebung mittels eines Walzenbettes unterworfen, wobei übergroßes Streugut aus dem Streuverfahren ausgeschieden wird,
• 1.2 das verbleibende Streugut wird anschließend einem gerichteten Luftstrom zugeführt und dort aufgeteilt einer Windsichtung und einer Zweitsiebung zugeführt,
• 1.3 wobei die Windsichtung mittels des Luftstromes und eines Flugspansiebes durchgeführt wird und gleichzeitig gegenüber dem Flugspansiebes übergroßes Streugut der Zweitsiebung zugeführt wird ..
• 1.4 wobei gegenüber der Zweitsiebung übergroßes Streugut aus dem Streuverfahren ausgeschieden wird und
• 1.5 aus dem Streugut aus der Windsichtung und aus der Zweitsiebung eine Streugutmatte oder eine Schicht einer Streugutmatte auf einem Formband gebildet wird.

The solution for the method according to claim 1 is that by the following method steps a grit mat can be created, which has no faulty grit:

• 1.1 the spreading material is subjected to a dissolution and screening by means of a roller bed, wherein excess grit is discharged from the spreading process,
• 1.2 the remaining grit is then fed to a directed air flow and there split a wind sifting and a second sifting fed
• 1.3 wherein the air classification is carried out by means of the air flow and a Flugspansiebes and simultaneously opposite the Spanspansiebes oversized grit of the second screening is fed ..
• 1.4 is compared with the second screening oversized grit separated from the scattering process and
• 1.5 is formed from the grit from the air classification and the second screening a grit mat or a layer of a grit mat on a forming belt.

• dass oberhalb des Luftstromes einer Windstreukammer ein Walzensieb mit zugehöriger Austragsvorrichtung für übergroßes Streugut angeordnet ist,
• dass im Luftstrom der Windstreukammer ein Flugspansieb angeordnet ist,
• dass unterhalb des Luftstromes ein Zweitsieb mit zugehöriger Austragsvorrichtung für übergroßes Streugut angeordnet ist und
• dass die untere Kante des Flugspansiebes zu dem Zweitsieb so angeordnet ist, dass zurück gehaltenes Streugut auf das Zweitsieb fallen kann.

The solution to the problem of a spreader is to

• a roller screen with associated discharge device for oversized spreading material is arranged above the air flow of a windbreak chamber,
• that in the air stream of Windstreukammer a Flugspansieb is arranged,
• that below the air flow, a secondary screen with associated discharge device for oversized spreading material is arranged, and
• in that the lower edge of the spreader screen is arranged with respect to the second screen so that the grit retracted can fall onto the second screen.

• Durch die doppelte Siebung und doppelte Abführung von übergroßem Streugut wird in vorteilhafter Weise vermieden, dass fehlerhaftes Streugut (Leimklumpen, Metalle, übergroßes Streugut und dgl.) in die Streugutmatte gelangt. Dazu wird mittels eines Walzensiebes das aus der Vorbereitung (Trocknung, Beleimung, Lagerung) kommende Streugut aufgelöst, über die Länge des Formbandes bereits nach Größe sortiert und übergroßes Material aus dem Streuprozess ausgeschieden. Das aufgelöste Streugut kann nunmehr vor dem Eintritt in den gerichteten Luftstrom mittels Auflösewalzen, bevorzugt aus Speichenwalzen wie aus EP 800 901 A1 bekannt, weiter aufgelöst werden und wird mittels des Luftstromes nach Grösse klassiert auf dem Formband abgelegt. Durch die Windsichtung mit einem Flugspansieb wird nochmals übergroßes Material zurück gehalten und einer Zweitsiebung zugeführt. Nicht durch den Luftstrom mitgeführtes Streugut und das vom Flugspansieb zurück gehaltene Streugut wird damit nochmals einer Siebung unterworfen um aneinander haftendes Streugut eventuell nochmals zu trennen und dem Formband zuzuführen oder um letztendlich fehlerhaftes Streugut aus dem Streuprozess auszuscheiden. Durch die kombinierte Mehrfache Siebung ist ein sicheres und gründliches Prozessverhalten der Streumaschine ermöglicht und es werden sichere und für die Presse unschädliche Streugutmatten produziert.

The method according to the invention and the scattering machine according to the invention have the following significant advantages:

• Due to the double screening and double discharge of oversized spreading material is avoided in an advantageous manner that faulty grit (glue lumps, metals, oversized grit and the like.) Arrives in the grit mat. For this purpose, the spreading material coming from the preparation (drying, gluing, storage) is dissolved by means of a roller screen, already sorted by size over the length of the forming belt, and excess material is eliminated from the scattering process. The dissolved grit can now before entering the directed air flow by means of opening rollers, preferably from spoked rollers like EP 800 901 A1 known to be further dissolved and is classified by size of the air stream on the forming belt. The air sifting with a spreader screen again oversized material is held back and fed to a second screening. Not entrained by the air flow spreading material and the backscatter spill held by the spreader screen is thus again subjected to screening to possibly separate again adhering grit and fed to the forming belt or ultimately excrete faulty grit from the scattering process. The combined multiple sieving enables a safe and thorough process behavior of the spreader and produces reliable grit mats that are harmless to the press.

The proposed installation of a flat or only a little used to Formband second sieve is only possible because a large part of the throughput of the spreader on the roller screen and the Flugspansieb has been spotted. The remaining amount that remains is easily sift through a flat-set sieve in perforated metal or wire mesh design, without clogging it. At the same time it is possible to compensate for the disadvantage of the roller screen, which has a relatively high percentage as error rate with a large sieve volume, and to significantly reduce its error rate or reduce it to zero. Furthermore, it is possible to introduce the fine grit directly into the air stream directly in the vicinity of the spinneret by grouping the clearance of the roller screen in groups. This supports the classification function of the air flow and enables the production of extremely fine cover layers with the smallest particles of grit on the surface of the grit mat or directly on the forming belt.

Due to the advantageous arrangement of the various screens, it is possible to significantly increase the throughput of the volume per hour in such a spreader over the prior art while minimizing the error rate of existing defective grit in the grit mat.
It should be noted that the secondary screening is carried out by means of a perforated plate or a wire mesh, which may preferably be subjected to a continuous but also a regularly occurring vibration.
Alternatively, of course, the second screening can also be performed with a roller screen and air classification can with several Fugspansieben be carried out, wherein preferably the following Flugspansiebe have a stronger effect than the first flowed through. It is also important that the air flow is directed parallel to the forming belt and can be controlled by the height of the windbreak chamber in intensity and volume. Advantageously, the air flow is supported at the end of the windbreak chamber with a suction and there should be a separator for particulate matter there.

Further advantageous measures and embodiments of the subject matter of the invention will become apparent from the dependent claims and the following description with the drawing.

Figur 1

in schematischer Seitenansicht einen Längsschnitt durch eine erfindungsgemäße Streumaschine,

Figur 2

einen Längsschnitt durch eine Streumaschine in einer weiteren Ausführungsform,

Figur 3

einen schematischen Anlagenaufbau zweier spiegelbildlich zueinander ausgerichteten Streumaschinen zur Bildung einer Streugutmatte und

Figur 4

einen Schnitt durch eine Streugutmatte gestreut mit einer Anlage nach Figur 3.

Show it:

FIG. 1

in a schematic side view of a longitudinal section through a scattering machine according to the invention,

FIG. 2

a longitudinal section through a spreader in a further embodiment,

FIG. 3

a schematic system structure of two mirror images of each other aligned spreading machines to form a grit mat and

FIG. 4

a section through a grit mat scattered with a plant of Figure 3.

In Figure 1, there is the schematic structure of a spreader 1 with a Windstreukammer 13. Depending on the expansion and execution of the production plant for wood-based panels is located in front of or above the grit entry a grit bunker (not shown). For this, over the width of the forming belt 14 by means of discharge rollers (not shown) the grit is controlled introduced into the grit entry 3 of the spreader and fed by a baffle 2 a roller screen 5 above the windbreak chamber 13. The roller screen 5 consists of mutually parallel rollers, which define by their distance from each other a gap size through which the grit 4 can pass through. The rollers can be made smooth or have a special surface pattern. In addition, the roller screen 5 is associated with a discharge device 11 for oversized spreading material 15 in order to remove this spreading material 15 from the scattering process. After successful passage of the grit 4 through the roller screen 5, the grit 4 hits a present in the wind striker 13 and directed air flow 10. Here, a screening and division of the grit 4 into heavy and lighter particles. The lighter and thus generally smaller particles are guided by the air flow 10 through the windbreak chamber 13 and land in this embodiment, first on the forming belt 14, which rotates with the direction 22. In this case, a first air classification of the material to be spread takes place by means of an oblique flight plane screen 7, which is thus arranged obliquely in relation to the air stream 10. This is again oversized grit 15 sorted out against the Flugspansieb 7 and finally falls on the secondary screen 6, which can be designed as a wire screen, perforated screen or in turn as a roller screen. While the grit 4 is passed over the second screen 6, still permissible grit 4 can fall on the forming belt 14, which is already covered with grit, with oversized grit 15 is finally eliminated by means of a discharge device 12 from the scattering process. As already mentioned, the spreading material 4 passing through the flying cut filter 7 drops onto the forming belt 14 or, depending on the design of the system, passes through one or more flight screens 8, 8 ', 8 "before it reaches the forming belt 14. The air flow 10 in Incidentally, the wind-ratchet chamber 13 can be brought about by a blower (not shown) and / or by a suction (not shown) and is regulated in accordance with the spreading material and throughput.
Advantageous developments of the subject invention are that a perforated plate or a wire mesh screen is arranged as a second screen 6, that is usually arranged at an angle of 5 - 10 ° to the forming belt.
In this case, the wire mesh screen can be designed with a hole spacing of 5 mm × 5 mm or 10 mm × 10 mm.
The flight saw screens 7, 8 and / or the second screen 6 (if not provided with rotating elements) is provided with a vibration drive 16 to increase the conveying effect in the direction of the discharge devices for oversized grit. Depending on the application, it may be advantageous to several It is expedient to arrange the flying sifting sieves 8, 8 ', 8 "... in the direction of the air flow in their sieving effect.
For maintenance purposes, it is of advantage that the flying sifting 7, 8, 8 '.... and / or the second sieve 6 from the spreader laterally movable out, depending on the capacity of the system even in direct exchange with just maintained sieves.

In Figure 2 is shown as a further embodiment, while under the roller screen 5, one or more opening rollers may be arranged, which are preferably designed as a spoke rollers 17 with a diameter of more than 450 mm. The spokes 18 may, as shown in left in spoked roller 1.7, be arranged on the outside or, as in the right spoked roller 17 in the manner of a spiral pattern from the inside out several times. Depending on the throughput or grit used, it may be advantageous to carry out the second wire as an endlessly circulating wire cloth belt, which is driven by a drive 20. The direction of rotation 21 shows for overhead oversized grit on the discharge 12..
In various applications, it is usually sufficient to adjust the rollers of the roller screen 5 in groups with different clear distances to each other. Even if all the rollers of the roller screen 5 are arranged with the same distance from each other so this is usually with a clearance of 0.5 to 4 mm done.

FIG. 3 shows how two scattering machines 1, 1 'according to FIG. 1 or 2 are arranged so as to be mirror images of one another, so that a spreading material mat 9 with two outer layers or outer layers is formed. This system works in such a way that on the forming belt 14 first a covering layer 26 with a very thin spreading material and then a middle layer 25 with the remaining spreading material from spreading machine 1 is formed. The downstream mirror-image standing spreader 1 'places on the existing layers (cover layer 26 and middle layer 25) of the grit 9 again a normal grit for the middle layer 24 and then finally again a cover layer 23 with very thin grit from. This results in simple means a Mehrschichtstreugutmatte with outer layers of very fine grit according to Figure 4. In particular, this is still on the state of the art EP 800 901 A1 directed.

Thin plates with thicknesses less than 4 mm are scattered only with two such spreading machines (wind scattering machines) according to the invention, since usually can not be safely removed with the conventional middle-layer spreading machines oversized or faulty grit. In large-scale systems for particle board production, which use the scattering machine according to the invention purely for covering layer production, can accordingly easily Middle layer spreaders are switched off to switch to thin plate production.

It should be pointed out that the spreader in its execution can not only serve to carry out the claimed method, but also realizes features essential to the invention on its own and thus can also be regarded as independent.

LIST OF REFERENCE NUMBERS

1.

spreader

Second

baffle

Third

grit entry

4th

grit

5th

Roller screen

6th

Zweitsieb

7th

Flugspansieb

8th.

Flugspansieb

9th

grit mat

10th

airflow

11th

discharge

12th

discharge

13th

Wind scattering chamber

14th

forming belt

15th

oversized grit

16th

vibration drive

17th

spoke rollers

18th

spoke

19th

endless wire mesh tape

20th

Drive for 19

21st

Direction of 19

22nd

Direction of 14

23rd

topcoat

24th

middle class

25th

middle class

26th

topcoat

Claims (29)

Process for the complete or layered production of a spreading material mat from chips, which is pressed in the course of the production of wood-based panels by means of pressure and heat, characterized by the following process steps: 1.1 the spreading material is subjected to a dissolution and screening by means of a roller bed, wherein excess grit is discharged from the spreading process, 1.2 the remaining grit is then fed to a directed air flow and there split a wind sifting and a second sifting fed 1.3 wherein the air sifting is carried out by means of the air flow and an airborne filter and at the same time the oversized spreading material is supplied to the second sifting opposite the airborne spinal sieve, 1.4 is compared with the second screening oversized grit separated from the scattering process and 1.5 from the grit from the air classification and from the second screening a grit mat or layers of a Spreading mat are formed on a forming belt. A method according to claim 1, characterized in that the secondary screening is performed by means of a perforated plate or a wire mesh. A method according to claim 1, characterized in that the second screening is performed with a circulating guided endless wire cloth tape. Process according to claims 1-2, characterized in that the secondary screening is carried out with a roller screen. Process according to claims 1 to 4, characterized in that after the roller screen, the grit is mechanically dissolved. A method according to claim 5, characterized in that the grit is dissolved with opening rollers and / or spoke rollers. Method according to one or more of the preceding claims, characterized in that the flying sifting screens and / or the secondary screen are subjected to a continuous or alternating vibration. Method according to one or more of the preceding claims, characterized in that the air classification is carried out with several Flugspansieben. A method according to claim 8, characterized in that the flight saw screens in the direction of the air flow have an increasingly strong screening effect. Method according to one or more of the preceding claims, characterized in that the roller screen is adjusted so that only grit can pass up to 4 mm thickness. Method according to one or more of the preceding claims, characterized in that the air flow is directed parallel to the forming belt. Method according to one or more of the preceding claims, characterized in that the air flow over the Height of the windscreen chamber in intensity and volume can be regulated. Method according to one or more of the preceding claims, characterized in that the air flow is supported at the end of the windbreak chamber with a suction. Scattering machine for the complete or layered production of a spreading material mat which is pressed by means of pressure and heat in the course of the production of wood-based panels,
characterized, - that above the air flow (10) of a windbreak chamber (13) a roller screen (5) with associated discharge device (11) for oversized spreading material (4) is arranged, - That in the air flow (10) of the wind-ratchet chamber (13) is arranged a fly-sweep screen (7), - That below the air flow (10) a second screen (6) with associated discharge device (12) for oversized grit (4) is arranged and - That the lower edge of the Flugspansiebes (7) to the second wire (6) is arranged so that the retained grit (4) can fall on the second wire (6). Scattering machine according to claim 13, characterized in that a perforated plate is arranged as a secondary screen (6). Scattering machine according to claim 13, characterized in that the flying spine (7) is arranged obliquely to the air flow (10). Scattering machine according to claims 14 to 16, characterized in that a wire mesh screen is arranged as a second screen (6). Scattering machine according to claim 17, characterized in that the wire fabric screen is designed with a hole spacing of 5 mm x 5 mm or 10 mm × 10 mm. Scattering machine according to one or more of the preceding claims, characterized in that a roller bed is arranged as a secondary screen (6). Scattering machine according to one or more of the preceding claims 14 to 18, characterized in that as a second screen (6) a circumferential endless wire cloth belt (19) is arranged. Scattering machine according to one or more of the preceding claims 14 to 21, characterized in that below the roller screen (5) one or more opening rollers are arranged. Scattering machine according to claim 21, characterized in that the opening rollers are designed as spoke rollers (17) with a diameter of more than 450 mm. Scattering machine according to one or more of the preceding claims 14 to 22, characterized in that vibration drives (16) for the flying sifting screens (7, 8) and / or the second screen (6) are arranged. Scattering machine according to one or more of the preceding claims, characterized in that a plurality of flying saw screens (8, 8 ', 8 "...) are arranged in series in the wind raking chamber (13). Scattering machine according to claim 24, characterized in that the flight saw screens (8, 8 ', 8 "...) in the direction of the air flow (10) have an increasingly strong screening effect. Scattering machine according to one or more of the preceding claims, characterized in that the flying saw screens (7, 8) and / or the secondary screen (6) from the spreading machine (1) are arranged laterally movable out for maintenance purposes. Scattering machine according to one or more of the preceding claims, characterized in that the secondary screen (6) is arranged at an angle of 5-10 ° to the forming belt. Scattering machine according to one or more of the preceding claims, characterized in that the rollers of the roller screen (5) are arranged at a clearance of 0.5 to 4 mm. Scattering machine according to one or more of the preceding claims, characterized in that the rollers of the roller screen (5) in groups have different clearances.

Images