DE102006028392A1 - Multilayered pressed material mat dispersing method, involves sealing and guiding upper area of dispersed mat by dispersion walls into adjacent dispersion machines along longitudinal edges after dispersion of mat on molded strap in machines - Google Patents

Abstract

The method involves dispersing a multilayered pressed material mat (9) on a molded strap (10) in a production direction from a molding press by a dispersion machine (1). The multilayered pressed material mat is introduced into the molding press, and the multilayered pressed material is brought into an end form by using pressure and heat. An upper area of the dispersed pressed material mat is sealed and guided by dispersion walls (3) into adjacent dispersion machines along longitudinal edges after the dispersion of the pressed material mat on the molded strap in the dispersion machines. Independent claims are also included for the following: (1) a system for dispersing a multilayered pressed material mat (2) a dispersion machine for dispersing a layer of a pressed material mat.

Description

The The invention relates to a method for scattering a multilayer Pressgutmatte from chips or shavings in the course of the production of wood-based panels According to the preamble of claim 1. In the following is an attachment for scattering a multilayer pressed material mat and a spreader presented for layered scattering.

Basically already processes, plants and spreaders for bulk or Scattering of small particles or large chips or chips known become. The relevant Technologies are for Particles and / or small chips under the umbrella term MDF board production, where MDF for medium density Fibers stands, has become known. But also in the field of OSB production, OSB stands for Oriented scattered plates, generic systems and methods were published.

The Improvements made in recent years usually refer to improvements in scatter quality different types of spreading machines or to an improvement in the treatment of the scattered material to the final Pressing by means of discontinuous or continuous press plants. Basically with the necessary mass production in the foreground a continuous create equivalent product with different parameters. Here play size, Art and density of the scattering particles used (input variables) as well an important role as the parameters of the final product in terms Density, thickness and type (output variables) of the material plates to be produced. The macroeconomic context is always in the background to pay attention to and preferred by the client plants, who can do it to produce a wide range of plate thicknesses of different sizes. The areas of the chipboard thicknesses to be produced in a system move from 3 mm thick thin plates up to 60 mm thick Countertops. Nevertheless, even on such facilities made up to 120 mm thick beam products. Converted to a stray road for the preparation of the pressed material mats to be pressed this means that a stray road should be capable of pressing material mats of a height of 10 mm up to a height of 1200 mm with consistent quality to scatter. It should be noted in addition to the scattering height that the scattering machines used for one Constant throughput of material to worry about density fluctuations in the pressed material mat and thus to avoid product quality fluctuations. in principle becomes the problem of the production of differently high pressed material mats solved by that several spreaders are arranged one behind the other and these over the Formband on which the pressed material mat is scattered, are designed adjustable in height. The problem here are the lateral seals of Pressgutmatte in the conveying direction of the form band. It is basically Note that each spreader has different types of rollers to dissolve the grit, to classify and / or oriented to put on the form band. Usually are opening rollers arranged and distributed at the top of the grit entry of the spreader the spreading material on the arranged below in the spreader spreader rollers.

critical for the spreading quality is now the distance of the scattering rollers to the forming belt or the already existing top layer of Pressgutmatte. It is known that at a great distance of suitable for orientation scattering rollers to the spreader surface the Spreading material is unoriented and at a small distance, an orientation is possible. Experience shows, that at a distance of more than 20 cm from the litter surface one is suitable for orientation Spreading roller deposits the material unoriented, since the drop height is sufficient is that the grit can twist. This is also understandable why a small spreading height distance is necessary to produce an oriented scattered Pressgutmatte. The exact distances are natural dependent on the type of spreading rollers and the spreading material itself.

Next the height adjustment the scattering rollers to the spreading surface However, the problem is the same for all spreading machines: the sealing the spreader to the forming belt to escape the grit the longitudinal edges of the To avoid spreader. In addition to the resulting fault in the Border area is natural also pollution of nearby plants and equipment due to dust or large chips or chips an undesirable Problem.

The patent literature already knows various proposals for solving this problem. So is with DE 22 54 064 A a fleece conveyor device has become known, which has set itself the task of achieving a seal between the forming belt and spreader, with as little material as possible to escape laterally and at the same time an optimal spreading of a nonwoven fabric can be made possible. In addition, this spreader should be able to operate with low wear. To achieve this is proposed to arrange flexible sealing members in the side walls, which rest with its lower edge on the conveyor base (forming belt) and thus lead to a seal. DE 22 54 064 A offers no solution, as is the case with several spreading machines an adjustment is possible to form different fleece heights, but has only rigid side walls, which are provided with "sealing lips." In addition, the sealing side wall has projections in the region of the longitudinal seal, which can lead to problems due to jammed grit or to erroneous discharges, since the lateral side wall to guide the scattered grit not smooth running but has gradations.

With DE 38 41 276 C1 a spreading machine for the spreading of wood chips has become known, which should allow a height adjustment of the scattering head in the production of different thickness Pressgutmatten while maintaining good longitudinal seal. For this purpose, a lateral boundary track is attached to the spreading head (scattering machine) and deflected in the region of the forming belt. The boundary track consists of a flexible material and is loaded by weights to tension them. Thus, although this device has a continuous smooth surface against the grit and also allows a proper seal, but requires on the one hand tribologically sensitive boundary paths that can be made by low material costs reasonably wear and tend to caking by glue residue and the grit. The proposed use of a continuous plastic, rubber or fabric web is particularly prone to caking or edging of vorbeifallendem or -schleifendem grit. By hanging weights in order to obtain sufficient tension in the boundary track for proper guidance of the material to be spread requires on the one hand a high-quality and sufficiently strong material, possibly with reinforcing fibers, and on the other prevents proper circulation around the deflection in the region of the forming belt. Another disadvantage is the use of large installation space, because the double deflection and the weights need a lot of space that can be useful for other system elements or must. The maintenance of the spreader is a problem, so the weights must be removed and stored when opening the lateral boundary track and then the de Begrenzungsbahn has to be laboriously threaded out or disassembled from the scattering head to get to the inside of the spreader.

Further is during operation the adjustment of the blind-like boundary track not without problems. On the one hand leads the regular application from resin residues to a stiffening of the boundary track and so on Problems with the first circulating roller near the forming belt, on the other hand can Caking, passing through the gap between pulley and forming belt The form band itself or the boundary track can be pulled and damaged to problematic signs of wear to lead. In the worst case, the caking is sheared off and as glue lumps carried in the Pressgutmatte. For systems with a lateral compression rail in front of the inlet the continuously working press to increase the edge density of the Material plate to achieve these glue lumps damage lead to the press used.

This The invention has now the task of a method, a Plant and a spreader for spreading a pressed material mat in the course the production of material panels to create the above Disadvantages does not have and next to it allows before or during the Scattering of new layers of Pressgutmatte already scattered layers in terms of their parameters while maintaining operational safety and the repair options improved.

The solution for the Method is that after formation of a first layer a pressed material mat on a forming belt in a first spreader in the subsequent spreading machines along the longitudinal edges only an upper area of the existing pressed material mat sealed by means of scattering walls and guided becomes.

The solution for one Plant for scattering of a multilayer pressed material mat consists according to claim 11 in that at least the first spreader for forming the pressed material mat on the forming belt per longitudinal side has a fixed scattering wall and that at least the last Spreader (below the core diameter of the spreader rollers) each long side an independent having vertically movable from the spreader spreading wall.

A Spreader with features to a solution of the task exists Claim 13 in that in the spreading machine parallel to the conveying direction the forming belt arranged scattering walls and the outer diameter the spreading rollers at substantially the same height, the lower end of the spreader limit and that parallel to conveying direction each longitudinal side the forming belt below the core diameter of the spreader rolls independent of the spreading machine is arranged vertically movable scattering wall.

In the system according to the invention, it is otherwise irrelevant whether only the spreader rollers are arranged to be adjustable in height even for different heights of Pressgutmatten or whether the entire spreader is designed to be height adjustable. Usually, the latter embodiment is used, since the distance between opening rollers and scattering rollers is usually predetermined or optimized. This is technically conditioned by the fact that the core diameter of the dissolving or scattering rolls are normally carried out in openings in the lateral walls of the spreader. Depending on the application, the dissolving or spreading rollers then have orientation disks, orientation compartments or spikes within the scattering machine which define the outer diameter of the dissolving and spreading rollers. A seal in rotationally symmetrical perforations of the lateral spreading machine walls is usually common and technical standard. In the execution problematic or expensive is the opening of the scattering walls in the passages for the core diameter of the rollers in the form of grooves or the like. Here, awkward and expensive blinds and scrapers must be introduced in the spreading machine walls, which complicate the structure and bring unpleasant side effects due to escaping grit in disturbances. In particular, the area of bearings and drive motors can be damaged in uncontrolled dust discharge. In addition, such breakthroughs in the side walls always entail the risk of caking of grit and, associated therewith, the demolition of lumpy and compacted material which can get into the pressed material mat.

The existing devices and systems according to the prior art of Technology have no way shown how to use as possible low technical effort a highly effective and simple cornering achieved with sealing properties in the scattering plane with simultaneous height adjustment the spreaders on different spreading heights with as smooth as possible and deserted lattice walls.

It has been shown in the scattered production of flat chips or chips, that the scattered layers already by their homogeneous scattering has sufficient lateral strength that the edges of the Layers of a Pressgutmatte not crumble, if already something Material about it additionally cumulative is. This applies especially to flat spreading material like schnitzel or chips too, but also particles with appropriate glue application are quite able to have a certain lateral stability in an uncompressed way. The usual applied edge density increase results in obliquely in the direction of Pressgutmittenlängsachse salaried scattering walls a further solidification of the edge area, so that, for example with two or three scattered layers, the lowest layer none support more need. This is especially true when oriented scattered pressed material the case, since here the weight of the overhead grit for one good stability the edge area provides. Accordingly, it is within the scope of the invention intended for a support to dispense with the lower layers or areas already "covered" with additional spreading material and only in the upper area of a Pressgutmatte, sideways to lead and to support.

Conveniently, can now in the exposed areas of Pressgutmatte a parameter check individual or more layers and these also in addition to the parameters of the Pressgutmatte adjusting fluids or for example high-frequency radiation is treated or checked. Such become Pressgutmatten by means of X-rays radiates to density peaks or Glue lumps to capture or they are with steam, a steam-air mixture or applied to other fluids. It is also conceivable the introduction of Components of a multi-component adhesive in the pressed material mat.

Advantageously, the features of the invention thereby help that in an exemplary product change from a 90 mm thick chipboard to a 9 mm thick chipboard and preferably at the same bulk density of the starting material for input material instead of a 1.2 m high Pressgutmatte only a 0.12 m high Pressgutmatte can be scattered without the distance from the outer edges of the scattering rollers is changed to the surface of the pressed product mat. This has the consequence that in a system with multiple scatter stations, the last spreading station has to overcome almost one meter of height difference to move from a spreading height of 1.0 to 1.20 m to 0.1 to 0.12 m. This example is able to show that fixed lateral scattering walls must have either vertical apertures with cumbersome groove seal for the core diameter of the scattering rolls, which are moved down or it must be arranged below the core diameter of the scattering rollers telescopically or louver-like movable the scattering walls. Such solutions are but cumbersome in use, maintenance and application by edges having and perforated scattering walls. Incidentally, the numerical examples or dimensions given are in no way limiting for the inventive idea, but represent an advantageous embodiment. Furthermore, the continuous guidance of the full height of the pressed material mat at a current maximum spreading height of 1.2 m quite disadvantageous. Does it lead to increased friction on the guide surfaces of the scatter wall panels. This is due to the fact that the lower layers undergo compression due to scattering of several layers lying on top of each other. However, especially in the outer region on the longitudinal edges of the pressed material mat, the already mentioned edge density increase usually takes place during the scattering, so that a stronger compression takes place here than in the longitudinal center region. This edge density increase becomes problematic from the second or third spreading machine, since the pressed material mat is minimal pushes outward and thus rubs on guide plates or spreader walls. The carefully scattered homogeneous pressed material mat experiences here in the edge area undesirable shifts of the material to be spread or the chips up to partial Aufkantungen of the material to be spread and associated undesirable side effects during hot pressing. This can lead to scattering of oversized chips at high density peaks to emergency shutdown of the plant, especially since the steel strips of a continuously operating press sensitive to density peaks.

From The advantage is therefore a low coverage of the upper part of the pressed material mat of about 5 to 30% by means of a lateral scattering wall, especially in oriented scattered chips for the production of oriented scattered OSB or plywood boards. As already can be described the uncovered Used areas of Pressgutmattenhöhe become measuring devices to be attached to or in the pressed material mat. Advantageously, in the pressed material mat penetrating measuring instruments running parallel to the forming belt be arranged, with no disturbing lateral guide walls in the lower Areas of Pressgutmatte are present. This can be done for Setting parameters with regard to humidity or temperature a vapor-air mixture, pure steam or cooling air in the lower layers the pressed material mat are introduced. Also would be an injection of hardener containing fluids in the Pressgutmatte conceivable depending on the parameter selection For example, in the lower layers of the chemical compound reactions to activate. Of course, it is particularly advantageous after scattering of the outer layers, For example, after the first or second spreader, this targeted before or during the scattering of the first middle layer with steam or a vapor-air mixture to treat. In specially oriented scattered different This is even in later stages Scattering machines conceivable as usual smaller particles, chips or chips are used in the top layers and the middle layers with large-area material be scattered. This results in a kind of sealing effect between Cover and middle layers, allowing a targeted lateral passage of fluids purely in the outer layers directly above the forming belt is conceivable.

In A system consisting of several spreading machines can, depending on the final product Number of spreaders and their design vary, for example can also the two first and last spreading machines each two cover layers with low altitude but high density sprinkle and the two middle scattering machines two middle layer layers with low density but high height. Accordingly Is it possible to equip the first spreading machines purely with fixed side walls or spreader walls and at least only the last spreader with an independently vertically movable Provide scattering wall. But the decisive factor is that usually the movable spreading walls only have a maximum height, the little more than the distance from the core diameter to the outer diameter the spreader rolls corresponds. For example, in one embodiment, the Core diameter of a spreader 20 cm, in the spreader existing spreading discs or spreading compartments have an outer diameter from 60 cm up. Accordingly, it should be up to the spreader to a few inches above to be able to lower the forming belt, the height the vertically displaceable screen should not exceed 25 cm. In a maximum retracted state so can the spreader with a minimum distance of the spreading rollers to the forming belt of 5 cm spreading material lay down. This embodiment is also not a limitation on the interpretation of the To understand the scope, it is only for better understanding Following the teachings of the invention and showing only a preferred Possibility. Such a spreader can but with the lateral scatter wall a distance of 20 cm between the uppermost layer of a pressed material mat seal and covered while still 5 cm of the already spread Pressgutmatte. That would be it a maximum utilization of this design with 6 spreading machines possible to create a 1.2 m high pressed material mat, provided that each spreader the maximum scatter height of 20 cm with a cover used by 5 cm. Because the latter spreaders usually the largest travel path may be necessary, the vertical extent of the extendable sliding wall. This can be done in spreaders with extreme height adjustments by that the scattering wall consists of two parts, one part over the longitudinal axis the formband side edge is arranged foldable, and as needed with high pressed material mats, the scattering wall up to a maximum of twice renewable would. The Flaps can be equipped with hydraulic or pneumatic actuators carried out become. Furthermore can the scattering walls still have an inlet extension, in the form of for example one Inlet radius or an inlet slope around the incoming upper longitudinal areas the Pressgutmatte, possibly by vibration of the forming belt slipped slightly outwards between the travel path of two spreading machines are again slightly to push inwards. Again, it is enough the upper layers of the pressed material mat back into the right shape because the lower layers of the pressed material mat is not tend to lose their shape.

In a further embodiment, the vertically movable spreading walls can formband be displaceable on the side in the direction of the longitudinal center axis of the pressed material mat to promote a density increase during the scattering of a layer in the edge region.

Regarding Maintenance is probably the most obvious Advantage that meanwhile or in the case of a blockage of the spreader, the lateral vertical movable walls simply move up to the area of the spreader and thus made accessible with the simplest means of the scattered area becomes. Especially the exchange of spreading rollers is thus simplified possible without awkward lateral walls or blind boxes to disassemble. The necessary space is limited on drives for height adjustment which can each be arranged at the end of the spreader and the amplified Spillway itself. Basically it is natural possible the drives for height adjustment to the height-adjustable spreader to bind, this changed not the fact that the litter wall is still independent of the spreader itself is arranged movable.

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.

It demonstrate:

1 a schematic section through the lower portion of a spreader on a forming belt with lowered spreader (left) and raised spreader (right),

2 a schematic side view of a plant for the production of wood-based panels consisting of several spreading machines and a press in the production of thin wood-based panels (above) and thick wood-based panels (bottom).

Since the introduction already makes extensive reference to the state of the art with reference to patent literature, it suffices only for the decisive area of a scattering machine 1 just above the band 10 in 1 display. Here, the grit entry is performed above the conventional opening rollers, not shown, and limited in the spreader by the all-round rigid spreader walls 2 , The direction of the fall 12 for the spreading material is directly on the spreading rollers 4 directed. As in 1 The left-hand illustration in the lowered position can be seen in the scattering machine 1 a thin existing pressed material mat 9 on the form band 10 , Here is the vertically movable scattering wall 3 in the direction of the core diameter K of the scattering rollers 4 moves and slides behind the fixed spreading machine walls arranged there 2 , The amplifications shown amplified 5 the spreading machine walls 2 serve as a seal and possibly also as a bearing of the scattering rollers 4 and their spreader drives 8th , In a spreader 1 Now you can use several spreading rollers 4 be arranged at the same distance to the forming belt or rising in the working direction. The left half shows in 1 while the use of scattered roofs 6 on the core diameter K of the scattering roller 4 , These serve as a rule for the transverse orientation of the material to be spread during the scattering. In the right embodiment find lenses 7 for longitudinal orientation of the material to be spread. Both applications have in common that by the orientation means on the core diameter K of the scattering rollers 4 an outer diameter A is formed. The area between the underlying outer diameter A and the surface of the forming belt or the already spread Pressgutmatte 9 is the spreading area, by means of the vertical drives 11 height-adjustable spreading walls 3 to be sealed. As already sufficiently stated, it is sufficient only the upper portion of the pressed material mat 9 in the further course of the spreading machines ( 1 . 1' . 1'' to 2 ) by means of a scattering wall 3 respectively. It is crucial that the scattering walls limiting the spreading area 3 have smooth and even surfaces to optimize the dispersion in the edge area. In an angular employment of the scattering walls 3 and / or the spreader walls 2 an edge density increase can be adjusted to the longitudinal center axis of the pressed material mat, this being preferred by the scattering machine walls set over the spreading rollers 2 happens. Accordingly, only the spreading machine walls 2 angled, since the scattering walls 3 as perpendicular as possible to the form band 10 should be arranged. An advantage of an embodiment of the scattering machine such that the fixed spreading machine walls 2 with their seals 5 not further in the direction of the forming belt from the spreader 1 protrude than the outer diameter A of the scattering rollers 4 , This ensures that the spreading area only by the vertically displaceable scattering wall 3 optimally guided and sealed.

As the vertical drives 11 for height adjustment of the scattering walls 3 in the inlet and outlet of the spreading machines 1 are arranged, advantageously enough space is available to between these devices 14 provide a treatment of the pressed material mat 9 allow with steam, a vapor-air mixture or other fluids. Also, the devices can 14 Means for checking or irradiating the pressed material mat 9 exhibit. Depending on the application, these devices 14 Of course, also come between the spreaders for use or there as a special unit even the pressed material mat 9 be arranged spanning.

In the not to scale 2 is a complete system for creating a pressed material mat 9 on a form band 10 shown, which example 6 scatterers 1 . 1' . 1'' , ... 1'' with a form band running underneath 10 and a subsequent press 13 shows. To the problem of the different spreading heights of a pressed material mat 9 In the case of the upper plant, a minimal scattering height was shown, in the lower plant a maximum scattering height. The press shown here 13 is a continuous press with two rotating steel belts, but can also be designed as a floor or multi-daylight press. In this case, the Pressgutmatte would have 9 either scattered on screens (not shown) or split in front of the discontinuous press. Due to the graphic inaccuracy was based on a marking of the scattering walls 3 in 2 waived. In further embodiments, it would be conceivable that between in the first or second gap between the spreaders 1 . 1' and 1'' Device for the targeted treatment of the on the forming belt 10 lying cover layers are arranged with fluids or electromagnetic waves.

1

spreader

2

Spreaders wall

3

stray wall (movable)

4

spreading roller

5

execution

6

Spreading fan (transverse)

7

lenses

8th

Spreading roller drive

9

press material mat

10

forming belt

11

vertical drive stray wall

12

falling direction grit

13

Press

14

contraption

K

core diameter

A

outer diameter

Claims (19)

A method for scattering a multi-layer Pressgutmatte from chips or chips in the course of the production of Holzwerkstoffplattenmittels with a platen press or a continuously operating press with two circumferentially arranged endless steel strips, being scattered in the direction of production in front of the respective press by means of spreading machines a multilayer pressed material mat on a forming belt, this Pressgutmatte then introduced into a press and there brought into a final shape using pressure and heat, characterized in that after the beginning of the dispersion of a pressed material on a forming belt in one or more scattering machines in the subsequent spreading machines along the longitudinal edges only an upper region of already spread pressed material mat is sealed and guided by means of scattering walls. Method according to claim 1, characterized in that that the upper area of the pressed material mat 5% to 30% of the existing height of Pressgutmatte includes. Method according to claim 1 or 2, characterized that the chips or shavings for the Pressgutmatte oriented to be scattered. Method according to one or more of claims 1 to 3, characterized in that for the production of a 1.2 m high Pressgutmatte 4 to 6 spreading machines are used. Method according to one or more of claims 1 to 4, characterized in that after the first spreader exposed areas of the pressed material mat between or in the spreading machines be controlled or treated with regard to their parameters. Method according to one or more of claims 1 to 5, characterized in that for controlling the parameters of Pressgutmatte in the spreading machines between forming belt and scattering wall measuring devices on or be introduced into the Pressgutmatte. Method according to one or more of claims 1 to 6, characterized in that the measuring devices either stationary or in-line be applied to Pressgutmatte. Method according to one or more of claims 1 to 7, characterized in that for adjusting the parameters of Pressgutmatte in the spreading machines below the scattering wall a steam-air mixture or a steam mixture for heating or a cooling one Gas is supplied for cooling. Method according to one or more of claims 1 to 8, characterized in that the layers having a hardener Gas flows through become. Method according to one or more of claims 1 to 9, characterized in that only the scattered layers of Pressgutmatte for the cover layers be treated. Plant for scattering a multi-layered Pressgutmatte from oriented scattered chips in the course of the production of oriented scattered wood-based panels (OSB), consisting of several arranged in series scattering machines ( 1 ), the spreading machines ( 1 ) opposite the forming belt ( 10 ) are arranged adjustable in height, characterized in that at least the first spreader ( 1 ) has a fixed scattering wall on the forming belt per longitudinal side to form the pressed material mat and that at least the last spreading machine ( 1 ) below the core diameter (K) of the scattering rolls ( 4 ) each longitudinal side one independent of the spreader ( 1 ) vertically movable scattering wall ( 3 ) having. Plant according to claim 11, characterized in that starting from the first spreader ( 1 ) the scattering walls ( 3 ) opposite to the transport direction have an inlet extension. Spreader ( 1 ) for scattering a layer of a multilayer pressed material mat ( 9 ) from grit in the course of the production of wood-based panels, wherein the spreader ( 1 ) is even height-adjustable and from the grit entry to the scattering rollers ( 4 ) fixedly arranged spreading machine walls ( 2 ) are arranged, characterized in that parallel to the conveying direction of the forming belt ( 10 ) arranged scattering walls and the outer diameter (A) of the scattering rollers ( 4 ) substantially at the same height the lower end of the spreader ( 1 ) and that parallel to the conveying direction per longitudinal side of the forming belt ( 10 ) below the core diameter (A) of the scattering rolls ( 4 ) one independently of the spreader ( 1 ) vertically movable scattering wall ( 3 ) is arranged. Scattering machine according to claim 13, characterized in that the maximum height of the vertically movable scattering wall ( 3 ) half of the outer diameter (A) of the scattering rollers ( 4 ) does not exceed. Scattering machine according to claims 13 or 14, characterized in that the scattering wall ( 3 ) and / or the spreading machine walls ( 2 ) are arranged to adjust an edge density increase at an angle of up to 5 ° to the vertical pivot. Scattering machine according to one or more of claims 13 to 15, characterized in that the scattering walls ( 3 ) opposite to the transport direction have an inlet extension in the form of an inlet radius or an inlet slope. Scattering machine according to one or more of claims 13 to 16, characterized in that the vertical drives ( 11 ) for height adjustment of the scattering walls ( 3 ) are arranged in the spreader inlet and / or spreader outlet. Scattering machine according to one or more of claims 13 to 17, characterized in that as vertical drives ( 11 ) for height adjustment of the scattering walls ( 3 ) are arranged single or double-acting hydraulic or pneumatic cylinders. Scattering machine according to one or more of claims 13 to 17, characterized in that as vertical drives ( 11 ) for height adjustment of the scattering wall linear conveyors such as belt or ball drives are arranged.