EP1442855A2 - Device for distributing granular material onto a continously travelling support, and bunker for the granular material - Google Patents

Abstract

The scattering apparatus (1) includes a roller arrangement (11) which is arranged in the discharge section (10) of a metering hopper (2). The roller arrangement processes the scattered grits. An independent claim is also included for a hopper.

Description

The invention relates to a device for spreading of Spreading material on a continuously moving surface as well Bunker for metered discharge of grit according to the preamble of patent claim 1 or claim 10.

In the manufacture of wood-based panels, in particular Fiberboard, the problem is that by the transport the fibers from the refiners to the actual drop point So-called fiber bales form in the spreading head. Caused this is usually due to wall friction, back combing, Screw conveyors, etc. cause the material recirculation and the fibers to spherical fiber agglomerates join together. These fiber bales are very undesirable because they turn into a cloudy in the finished fiberboard Surface structure lead and a visual quality defect represent.

Furthermore, it may be in devices in which a Material stream of glued wood particles or fibers moves, too Caking and deposits come, which then suddenly through Vibrations or other forces are detached and with the Material flow be entrained. These deposits exist usually from a fiber-glue mixture that through the long Lying time is already completely cured. These Deposits are subsequently referred to as fiber / glue nodes designated.

These fiber / glue knots, especially in the production of thin wood-based panels of 2.5 - 8 mm and especially at high densities of 800 - 1000 N / mm ² cause severe damage to the steel strips of continuous presses. For the resolution of the fiber bales described above, as well as for breaking the fiber / Leimknoten so-called fiber opening rollers are used. These are usually arranged the dosing hopper and the spreading head assembly.

Fiber opening rollers usually consist of 1 or 2 pairs Opening rollers with very high speeds from 800 - 2000 Rotate revolutions per minute in opposite directions.

From DE 100 53 129 A1 are counter-rotating toothed Disc rollers or spiked rollers known on the perimeter arranged in rows arranged sting, which between the Intervene spiked rows of the opposite roller. Of the Material flow is characterized by the between the spines formed gap formed. The opening rollers are in Material flow between dosing bunker and spreading head arrangement arranged.

In modern plants for the production of wood fiber boards with high plant capacities must the fiber opening rollers as Double or triple roller pairs are executed because otherwise the high throughput will not be processed can. The opening rollers are operated at high speeds and require a solid frame with integrated Vibration damping. This structure has the disadvantage itself, that the fiber disintegrator a large Requires space. The dosing bunker and all Feeders must be set one floor higher become. In addition to the high investment costs for the Fiber dissolving device itself, additional costs through the more expensive steel construction and the required additional hall height.

The in the plants for the production of wood-based panels used dosing bins are from the textbook of Deppe / Ernst, Paperback of the chipboard technology, 3rd edition 1991, page 155. There is a horizontal dosing bunker shown in which the material flow over a Screw conveyor is entered above. Through a horizontal swiveling process distributes the screw conveyor the Material flow continuously over the entire bunker width. At the Bunker floor is a floor tape provided, which is the spreading material continuously with a low feed to one Discharge opening conveyed.

So that as even as possible amount in the scattering head is discharged, is in the bunker a back combing device provided by a constant filling level through Backscrap is generated. Above the discharge opening are arranged over the entire bed height discharge rollers, the on the bottom belt brought up on spreading material Remove underexposed opening rollers.

Object of the present invention is an apparatus for Production of wood-based panels as well as a bunker for to develop the device such that a qualitative high quality wood based panel can be made, and whereby a high throughput and a small footprint achieved is and continues to minimize the manufacturing and construction costs becomes.

This object is achieved in that in the discharge area the dosing bunker instead of the usual Austragswalzenanordnung a Auflösewalzenanordnung used becomes.

This allows the otherwise additional between dosing bunker and scattering head assembly disposed opening rollers omitted. The fast-rotating opening rollers meet both the Function of the resolution as well as the uniform discharge. Due to this training height and more Saves manufacturing costs for additional rollers.

As in the discharge of the dosing bunker, the usual Bunkerfüllhöhe 2000 - 3000 mm own, a variety of Opening rollers can be arranged, can be a high Throughput can be realized.

In one embodiment, it is provided that all Opening rollers a direction of rotation in the same direction, with the exception the top opening roller, own.

Here is a good resolution of the fiber / Leimknoten achieved.

In this preferred mode, first, fibers will be on every interface between the existing rollers Second, the relative velocity between neighboring spiny disks much higher, as the Add peripheral speeds and thirdly arises uniform obliquely downward fiber discharge with low air turbulence.

In the experiments, it has surprisingly been found that the discharge in the same direction rotating fiber opening rollers works smoothly and without tendency to pulsation. in the Connection to the opening rollers are only slight Air turbulence and the variant brings one down directed discharge stream with it. The latter arises in that all the opening rollers on the discharge side after turn down and thus an air flow down, which entrains the very light fibers.

In principle, air turbulences arise at the exit of the Fiber opening rollers. These air turbulences are very disturbing because the air swirls tear the light fibers with them and thus an unwanted, uncontrolled distribution in Create transverse direction. Nevertheless, a good scatter result too and especially an uncontrolled redistribution in To avoid transverse direction, the invention sees in one Continuing the arrangement of wall elements before, the Divide flow into several streams. The Wall elements are spaced from each other vertically and longitudinally to the conveying direction. For the purpose of influencing the Cross distribution are in one embodiment, the wall elements adjustable. This can be through the Wall elements forming shafts opening individually downwards or closing. Furthermore, this is by this also an adjustability for the purpose of changing the spread imaginable.

The invention will be described with reference to embodiments which are shown in FIG The drawings are illustrated in more detail.

Fig. 1:

eine Seitenansicht einer Streustation mit Dosierbunker, Beruhigungsfächer sowie Streuvorrichtung;

Fig. 2a,2b:

eine Ausführungsform eines Auflösewalzenpaares in Seitenansicht und ein Teilausschnitt in Draufsicht;

Fig. 3a,3b:

eine weitere Ausführungsform eines Auflösewalzenpaares in Seitenansicht und ein Teilausschnitt in Draufsicht;

Fig. 4:

zeigt im Ausschnitt eine Frontalansicht eines Beruhigungsfächers;

Fig. 5:

eine weitere Ausführungsvariante einer Streustation mit Dosierbunker, Beruhigungsfächer und Streuvorrichtung;

Fig. 6:

eine Seitenansicht einer Streustation mit verschwenkbar ausgebildeten Teilwänden des Beruhigungsfächers;

Fig. 7a,7b:

eine Seitenansicht einer Streustation mit Beruhigungsfächer sowie Aufgabeklappe mit Leitblechen und ein Teilausschnitt des Details Führungsgabel / Leitblech;

Fig. 8:

eine Seitenansicht einer Streustation mit Expansionsraum und Luftabsaugschacht;

Fig. 9:

eine Seitenansicht einer Streustation mit Schwergutabscheider.

Show it:

Fig. 1:

a side view of a scattering station with dosing bunker, sedation and scattering device;

2a, 2b:

an embodiment of an opening roller pair in side view and a partial detail in plan view;

3a, 3b:

a further embodiment of an opening roller pair in side view and a partial detail in plan view;

4:

shows in the section a frontal view of a calming fan;

Fig. 5:

a further embodiment of a scattering station with dosing bunker, calming fans and scattering device;

Fig. 6:

a side view of a spreading station with pivotable part walls of the calming fan;

Fig. 7a, 7b:

a side view of a scattering station with calming compartments and task flap with baffles and a partial detail of the details guide fork / baffle;

Fig. 8:

a side view of a scattering station with expansion space and air extraction shaft;

Fig. 9:

a side view of a spreading station with heavy material separator.

In Fig. 1 of the drawing is schematically a scattering station. 1 with a dosing bunker 2, a calming fan 3, a Scattering roller assembly 4 and a forming belt 5, to which the Material fleece 6 is sprinkled from free-flowing material, shown.

As free-flowing spreaders are in the first place lignocellulosic and / or cellulosic particles different size such as fibers, chips and the like intended. Zer production of fiberboard are usually with Binders provided using wood fibers.

These glued wood fibers are not over one shown screw conveyor in the entry area 7 of Metering bunker 2 registered. Through a swivel process The screw conveyor distributes the fibers over the whole Hopper width. At the bunker floor a bottom band 8 is provided, on which the wood fibers are applied and that the whole Applied fiber layer slowly to a discharge area 10th promoted. So that as even a quantity as possible from the Dosing bunker 2 is discharged, is the top of the dosing bunker. 2 a Rückkämmvorrichtung 9 in the form of a back pressure rake provided by which a constant filling level is generated.

Above the discharge area 10 are over the entire Schütthöhe opening rollers provided, the one Forming opening assembly 11 form. By means of Opening roller assembly 11, the material flow of wood fibers dissolved and in a directly downstream Sedation 3 entered.

As can be seen from Fig. 1, are in the discharge area 10 a plurality of individual opening rollers 12 in parallel spaced apart, wherein the opening rollers 12 starting from the bottom belt 8 in the vertical direction to the backscrap 9 out are arranged offset obliquely. One by the Rotation axes of the opening rollers 12 extending plane E points in this case to a vertical V at an angle α.

From the illustration to Fig. 1 is further apparent that the opening rollers 12 rotate counterclockwise are driven (arrows 13), wherein the top, the Backscrap rake 9 closest opening roller 12 in opposite directions is driven in rotation.

In this mode, the opening rollers with in Compared to previous fiber opening rollers low speeds be operated from 200 to 800 rpm.

Further details of the opening rollers 12, the Drawings to Figs. 2a, 2b, Fig. 3a, 3b are taken.

The opening rollers 12 each have one as a cylindrical Base 14 trained rotary shaft, with a variety Spacing disks arranged on the main body at a distance 15 are provided.

Between the arranged on the opening rollers 12 adjacent dissolving discs 15 are each spacers 16th inserted. The dissolving discs 15 axially spaced apart the opening rollers 12 are arranged, projecting in the middle like it 2b is visible, in the interspaces of the on the adjacent opening roller 12 axially spaced Disintegrating discs 15. The dissolving discs 15 are made of a Spring plate made. The sheet thickness of the slices 15 is 1.5 mm in this embodiment.

The slices 15 have, as shown in FIG. 2a it can be seen, an annular portion of which evenly distributed over the circumference of the release elements 17 radially extend outwards, between which recesses remain. The dissolving elements 17 are substantially rectangular educated. Furthermore, they are centered on their faces provided radially inwardly tapered recesses, so that at each opening element 17 end two tips 18th arise.

As can be seen by the double arrow 19 in Fig. 2b and 3b is, the distance between adjacent rolls can be changed become.

In Fig. 2a, 2b is a combing state adjacent Opening rollers 12 shown. With Ü is a measure of the Overlap area of the slices 15 adjacent Opening rollers 12 referred.

In Figs. 3a, 3b is a non-combing state represented, in which the slices 15 a gap distance S have.

It is noted at this point that the Opening rollers 12 also designed with other constructive Be provided dissolving elements or spines or the like can.

The flow of glued fibers is through the narrow driven gap formed between the spines or teeth, whereby a fiber dissolution or destruction of fiber / glue nodes is achieved. The dissolved material flow is in Connection to the opening roller assembly 11 in a arranged immediately downstream calming fan 3rd thrown (arrows P).

The calming compartment 3 consists of a housing part, in which a plurality of parallel wall elements 20 are arranged are. The wall elements 20 are preferably as longitudinal to Conveying direction of the forming belt 5 aligned sheets trained and divide the housing part in several Calming chambers 21 (illustration Fig. 4).

Due to the division into several calming chambers arise several uniform partial flows, which influence individually are to optimal distribution on the forming belt 5 to to reach. To such an influence in particular in the To achieve width, at least as many wall elements 20 to provide that at least three partial flows arise. Because in the practice plate widths to approx. 3 to 4 meters are usual, have calming fans of about eight to thirty Parallel currents proved to be advantageous. The conveying direction is vertical to the material particles from the top Dosing bunker 2 arranged on the underneath To promote scattering roller assembly 4. The soothing fan can but also be arranged obliquely to the vertical direction to at the same time to achieve a horizontal conveying component. The reassurance fan can also oblique to the Be aligned delivery direction to the flow rate also to deflect laterally.

As can be seen from the illustration of FIG. 1 are the wall elements 20 at its upper, the opening rollers 12th facing area, each semicircular, the contour of the Opening rollers 12 formed accordingly recessed. As a result, the wall elements 20 immediately after be arranged on the opening roller assembly 11 and it there remains only a small gap between opening rollers 12 and Upper edge of the wall elements 20 of the calming compartment 3. By This arrangement can not have fibers on the top of the Deposit wall elements 20 and a fiber / Leimknotenbildung can be prevented. The wall elements 20 protrude starting from the opening roller assembly 11 in the vertical direction to short via a task flap 22. The task flap can also in order to adapt to different panel thicknesses around the Rotary axis D to be pivoted.

The driven by the opening roller assembly 11 material flow gets into the calming chambers with high kinetic energy 21 of the calming fan 3 catapults. The existing ones Air streams together with the fibers are now considered parallel Partial flows passed in the calming chambers 21 down. There may be turbulences in the individual calming chambers 21 arise, however, due to the spatial limitation prevents a significant redistribution of the Material flow in the transverse direction can come.

Following the reassurance 3 arrive in the individual calming chambers 21 led down Partial streams on an underlying arranged task flap 22, which supply the material flow of a scattering roller assembly 4.

The scattering roller assembly 4 consists of several parallel and Spreader rolls arranged transversely to the conveying direction. The Spreader rollers are horizontal along the direction of conveyance rising line arranged to a uniform dispersion and to ensure a height limit. The spreading rollers are here directly below the task flap 22nd provided and promote the free-flowing goods, preferably the glued wood fibers against the conveying direction. By the rotation of the spreader rolls are simultaneously the Wood fibers on the continuously running underneath the forming belt 5 sprinkled as a non-woven fabric and a subsequent Prepress station or a plate press supplied.

In a further embodiment not shown could also after the reassurance subjects an additional Conveying device may be provided which the flow of material glued fibers feeding a scattering head assembly. The additional conveyor is here as feeder belt formed, which is continuously adjustable in flow rate the spreading head arrangement promotes, so that depending on the plate thickness and width of the scattering head assembly a predetermined amount is streubar on the forming belt.

5 shows a further embodiment of a scattering station for spreading glued scattered goods in the course of production of fiberboard, in which the opening rollers each driven in pairs in opposite directions. As it is from the Fig. 5 it can be seen here are in the discharge area 10 of the Dosierbunkers 2 four pairs of opening rollers 12 provided. In this arrangement, the paired opening rollers with operated at different speeds, so at the Interface a relative speed between the Opening rollers are created, which leads to a resolution of the fiber / glue nodes leads.

Same parts already described above are the same Provided with reference numerals. Those already described above different embodiments of the embodiment the scattering station acc. of Fig. 1 also apply to in the Fig. 5 schematically illustrated embodiment of the Spreading station 1 '.

The wall elements 20 are opposite to a stationary Housing part pivoted at least in some areas or slidably mounted so that the distances of the wall elements 20 from each other continuously or gradually adjustable are.

For adaptation to different manufacturable Plate widths or, for the purpose of influencing the Material distribution in the transverse direction is an embodiment provided in which the wall elements 20 executed in two parts are and in the lower part part walls 23 have, which is a Axis A are pivoted by means of an adjusting mechanism 24 can. This adjustment allows the distance between the wall elements in the lower area at the to Streupwalzenanordnung 4 facing side can be varied. By the fixed wall elements 20 in the upper, the opening rollers 12 facing area, the entry of the material flow remains in the calming chambers 21 constant.

Fig. 7a shows a scattering station 1 '' 'in contrast to the variant according to. Fig. 1 in the lower of Task door 22 facing area baffles 26 is provided are.

For this purpose, the wall elements 20, as well as the neck Fig. 7b can be seen in the lower area than Guide fork 25 is formed. On the task flap are in Lengthwise spaced, the wall elements 20 each associated baffles 26 attached in the Führüngsgabeln 25 are guided sliding.

Through this training, the partial flows of the Calming chambers 21 by means of the baffles 26 to Streuwalzenanordnung 4 led, so that also in the field of Task flap 22 no unwanted redistribution in Transverse direction can arise.

To reduce unwanted air turbulence in the air Connection to the opening roller assembly 11 arise is in Fig. 8 shows a variant in which behind the opening roller assembly 11 a large-volume expansion space 27 is formed, wherein additionally via a suction duct 28 an indirect suction of the air takes place.

The high momentum caused by the fast-spinning Fiber dissolving rolls arises, can continue to be used to Heavy goods, such as Glue / fiber lumps that are not dissolved or to separate other foreign bodies from fiber flow. For this purpose, as shown schematically in FIG. 9, parallel spaced in front of the Austragswalzenanordnung 11 a Shaft 29 are arranged with opening slots 30. The Foreign bodies, which are much heavier than the fibers of the Material flow, due to the high kinetic energy Thrown much further and get, as it by the Arrow 31 is shown through the opening slots 30 in the designed as a shaft heavy material separator. At the bottom Area of the shaft 29 is a screw 32, the the trapped in the shaft heavy parts from the Spreader carried out.

In principle, a variant is possible in the is dispensed with the training of a calming fan and the dissolved material flow directly to a Streussopfanordnung is abandoned.

Claims (10)

Apparatus for spreading glued spreading materials, in particular chip and fibrous goods in the course of the production of wood-based panels, with a dosing bunker for discharging the glued spreading material, an opening roller assembly for dissolving the spreading material, comprising at least two adjacent rotatably arranged with rollers provided with rolling elements and with a Spreader roller arrangement, by which the grit is aufstreubar on a forming belt, characterized in that the opening roller assembly (11) in the discharge region (10) of the dosing bunker (2) is arranged. Device for spreading glued sprouts after Claim 1, wherein the opening roller assembly (11) consists of a plurality of opening rollers (12), the pairs are arranged in opposite directions rotating, wherein the opening rollers (12) of a pair different Have speeds. Device for spreading glued sprouts after Claim 1, wherein all of the opening rollers (12), with Exception of the uppermost opening roller in the vertical direction (12), have the same direction of rotation. Device for spreading glued sprouts after one of the preceding claims, wherein all Opening rollers (12) adjustable in the axial distance from each other are arranged. Device for spreading glued sprouts after one of the preceding claims, wherein directly to the opening roller assembly (11) arranged downstream of a calming compartment (3), from several in the conveying direction next to each other arranged, extending longitudinally to the conveying direction Wall elements (20), wherein the wall elements (20) form a plurality of calming chambers (21). Device for spreading glued sprouts after one of the preceding claims, wherein the Wall elements (20) in which the spreading head assembly (4) facing area have separate partial walls (23), the are arranged pivotably via adjusting means (24), so that the discharge in the lower area in the transverse direction is changeable. Device for spreading glued sprouts after one of the preceding claims, wherein the Wall elements (20) via corresponding adjusting means at least in sections transverse to the direction of movement of Molded strip (5) are designed to be displaceable. Device for spreading glued sprouts after one of the preceding claims, wherein in Area behind the Austragswalzenanordnung (11) a Expansion space with air extraction shaft (28) is provided. Device for spreading glued sprouts after one of the preceding claims, wherein behind the opening roller assembly (11) spaced parallel Heavy Duty Collection Shaft (29) with Entry Grille (30) is arranged Dosing bunker for the device acc. To claim 1, for the metered dispensing of free-flowing spread materials, in particular chipboard and fiber-shaped goods, with an entry area, a storage area and a discharge area for the spread materials, wherein the discharge region comprises a Austragswalzenanordnung, characterized in that the Austragswalzenanordnung is designed as opening roller assembly (11), which consists of several, provided with opening elements opening rollers (12).

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