EP2922671B1 - Free-fall shaft arrangement with double cleaning unit, more particularly for a device for the gluing of particles during production of board - Google Patents

Description

The present invention relates to a chute arrangement according to the preamble of claim 1.

The production of material plates from, for example, chips or medium-density fibers or other free-flowing materials are now automated processes and have already been used in many countries for many years. As is known, 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. The urge to produce cost-effective material plates from natural raw materials and artificially produced binders forces producers to develop more and more efficient processes. Special emphasis is on low downtime and low wear.

The present development relates to the field of gluing the particles with a binder. Basically, the term binder is understood to mean a so-called adhesive liquor which consists of an adhesive in its main component. Depending on requirements, in addition emulsion, hardener, formaldehyde scavengers, dyes, insect repellent and antifungal agents and other additives are added. It is also common to use the adhesive without additives.

The following are suitable as binders without any claim to completeness: isocyanates, MDI, melamine urea formaldehyde (MUF), urea formaldehyde (UF), MUPF or PF.

The gluing is typically carried out such that the grit or the particles are introduced by means of a metering device in a chute and by means of nozzles which are arranged in the chute or this upstream, is acted upon or become the binder. The glued spreading material is usually in a downstream of the chute drum with rotating conveying tools (mechanical mixer) treated and / or glued on and then sprinkled to a grit mat and then pressed in real time, before curing a glue. Alternatively, the grit may be introduced directly into a spreader without passing through a mechanical mixer to sprinkle the grit mat and then crimp.

Such a device is for example off DE 10 2010 064 339 A1 known.

Here, there is the problem that binders and particles glued to the binder may accumulate on the inner wall of the chute so that the chute tends to become soiled. This makes it necessary to clean the chute regularly. For this, the plant usually has to be shut down, which brings with it a corresponding loss of production.

In addition, there is the possibility that solid deposits of not negligible size may form on the inner wall of the chute over time. If such deposits dissolve and fall into the mixer, it is not ensured that such lumps of solid deposits in the mixer are crushed and dissolved. It may therefore be in the paste of glued particles leaving the mixer, further solid lumps, which in the further course of the production of material plates can lead to impairment of product quality and / or damage to the presses.

In order to prevent or reduce the soiling of the inner walls of a chute and the formation of solid deposits on these, is in the document WO 2011/134844 A1 proposed to cover the inner walls of the chute with doctor blades or spatulas. The spatulas are firmly attached to a support structure consisting of an upper ring and a lower ring. The upper ring is connected to a toothed ring with internal teeth, which is driven by a pinion and a motor. Driven so driven the doctor blades in a rotational movement about a vertical axis on the inner wall of the rotationally symmetrical chute.

Although it can be prevented in this way that form larger deposits on the inner wall of the chute, but at the price that new elements and surfaces are introduced into the chute with the doctor blades, which in turn soil and on which solid deposits can form. Thus, it can happen, especially in large plants, that can form on the doctor blades caking, which weigh up to 50 kg and can fall off in a lump, which can lead to damage of the mixer and / or the subsequent machines.

In the document WO 2011/134844 A1 Therefore, it is proposed to cool the doctor blades to a temperature which is below the condensation point of the humidity, so that a condensate film is formed on the surfaces, which is intended to reduce the adhesiveness of the injected chemical components, in particular of thermosetting adhesives.

Depending on the requirements of a particular application, in particular depending on which binder and / or which additives are used, it may be undesirable that condenses moisture in the chute. In this case, the document WO 2011/134844 A1 proposed doctor blade cooling can not be used effectively.

In other cases, depending on the binder used and / or the additives used, the effect of a condensate film is not or only slightly, so that adhesion is only slightly reduced, or even reversed, if certain binders or additives in moisture and / or at reduced temperatures show an increased tendency to stick and / or clump together. Even in these cases, a use of the document WO 2011/134844 A1 proposed Schaberklingenkühlung not be displayed.

In addition, it is for the realization of the document WO 2011/134844 A1 proposed Schaberklingenkühlung required to provide appropriate supply lines and discharges for a cooling fluid having a sufficient delivery capacity. In order to supply the walls of a rotating chute and / or rotary doctor blades with the cooling fluid, it is also necessary that appropriate fluid-carrying coupling means are provided which allow a transfer of cooling fluid from a stationary part of the system to the rotating chute walls and / or the rotary doctor blades. The mechanical structures required for this can be a great effort and it may be difficult to achieve a permanently effective seal.

It is therefore an object of the present invention to provide a chute assembly which can effectively prevent the formation of solid buildup within a chute.

It is therefore an object of the present invention to provide a chute assembly which is applicable to chutes of various shapes.

Further, it is an object of the present invention to provide a chute assembly that can be easily integrated into already built facilities.

These and other objects of the invention are achieved by a chute assembly according to claim 1. Further preferred embodiments are set forth in the dependent claims.

As a solution, a chute arrangement is specified, in particular for a device for gluing particles which at least partially consist of fibers and / or chips suitable for producing material plates, wherein the chute arrangement has a chute which has an inlet for feeding the particles and an outlet for delivering the particles, at least one first cleaning device for cleaning at least one inner wall of the chute and at least one second cleaning device for cleaning the at least one first cleaning device.

While the first cleaning device allows to keep the inner wall or the inner walls of the chute clean, the second cleaning device allows the first cleaning device to be cleaned as well. It can thus be effectively ensured that no solid deposits form in the chute.

In a preferred embodiment, the first cleaning device can be designed as at least one movable support element which is arranged to be movable relative to an associated first inner wall of the chute relatively, in particular parallel, wherein at least a first stripping element is arranged or formed on the movable support element, such stripped assigned inner wall when the movable support element is moved.

In this way it is possible to realize an effective and reliable first cleaning device with relatively little design effort.

The movable support member may be arranged to pass through a gap formed between two adjacent inner walls or between two ends of an inner wall.

It is also contemplated that the support member simultaneously represents a partial wall of the chute or an inner wall of the chute.

The movable support member may be formed as a wall, with a height corresponding to the stripped height of the associated inner wall.

Preferably, the movable support member may be formed resiliently.

The second cleaning device may in particular comprise at least one second stripping element.

In particular, the second stripping element can be arranged on a wall or a carrying element.

In this way it is possible with relatively little design effort to realize an effective and reliable second cleaning device.

It is in particular possible to form the movable support element as a wall element of the chute which forms an inner wall of the chute.

The chute may have a plurality of wall elements, which are each formed arcuate, wherein each wall element partially overlaps another wall element on the outside thereof.

In a further preferred embodiment, the first cleaning device may have at least one first scraper associated with the at least one inner wall, and the second cleaning device may include at least one second scraper and drive means for moving the second scraper from a rest position along an axis substantially parallel to the scraper such as to scrape off the first scraper

In another preferred embodiment, the first cleaning device may comprise at least a first scraper and drive means for moving the first scraper from a rest position along an axis substantially parallel to the at least one inner wall, so as to scrape off the first inner wall, and the second cleaning device at least a second scraper and drive means for moving the second scraper from a rest position over the first scraper positioned in the rest position, so as to scrape off the first scraper.

In yet another preferred embodiment, the first cleaning device may have at least one flexible stripping element, in particular an endless stripping element, for cleaning the at least one inner wall.

The use of a flexible stripping element has the advantageous effect that the stripping element can easily adapt to different shapes of the chute.

In particular, the chute arrangement may further comprise a first guide device and a second guide device, wherein the first guide device and the second guide device are arranged to hold and guide the at least one stripping element in a tangential direction relative to the at least one inner wall between the stripping element and the at least one inner wall of the chute to allow, further driving means are provided, which are adapted to act on the chute, the first guide means, the second guide means and / or the at least one stripping element for generating the relative movement.

Preferably, the first and / or the second guide means comprises: a plurality of guide means, in particular guide rollers or guide gears, and an endless guide element, in particular an endless guide cable, an endless guide belt, an endless guide wire or an endless guide chain, which or which circulates the guide means wherein the at least one flexible stripping element is attached directly or via holding means and / or deflection means to the endless guide element.

In particular, the use of a rope or a wire has the advantage that this or this can be very varied in structure and already unprocessed has a rough surface, which is particularly suitable for cleaning. In addition, both have a relatively small surface, which effectively precludes the formation of large adhesions. In addition, due to its high flexibility, a rope has relatively high self-cleaning characteristics and is also easy to clean.

The endless stripping element can be arranged by means of deflecting means to enclose a wall element of the chute which has at least one inner wall.

The endless scraper element can also be arranged so that it is arranged running in the region of the inner wall within the chute.

When the endless scraper element is disposed to extend within the chute, two portions of the endless scraper element are located adjacent the inner wall so as to provide a double stripping action by the endless scraper element.

Drive means may preferably be provided which are set up to set the at least one flexible stripping element into a reciprocating movement in the direction of the longitudinal extension of the stripping element.

By the reciprocating movement of the scraper element, which can be in particular an oscillating movement, the stripping effect, which the scraper element on the inner wall or deposits, which adhere to the inner wall, can be improved.

Preferably, two winding devices are further provided, wherein the flexible stripping element is connected to the winding devices in order to be wound and unwound by the winding devices can.

It can further be provided drive means which are adapted to put the endless stripping element in a circumferential movement.

By the circumferential movement of the scraper element, which in particular can be combined continuously, intermittently and / or with a reciprocating movement, the stripping effect which the scraper element adheres to the inner wall or to deposits adhering to the inner wall can be improved.

The at least one endless stripping element may extend adjacent the at least one inner wall of the chute in a substantially horizontal direction.

The at least one endless scraper element can also extend adjacent to the at least one inner wall of the chute in a substantially vertical direction and / or extend correspondingly to a shape of the chute in the vertical direction.

It can further be provided clamping means which are arranged so on the first guide means and / or the second guide means and / or the at least to act a scraper, that the at least one scraper element is kept under tension.

The stripping element can be guided past the second cleaning device or guided through the second cleaning device.

The second cleaning device can also be designed as a fluid bath, a brush, a wiper edge, or a stripping cylinder.

Preferably, the second cleaning device can be configured as an obstacle arranged or insertable in the travel path of the at least one stripping element.

The insertable obstacle may in particular be arranged in a wall of the chute having the at least one inner wall, wherein the engageable obstacle projects between a first position in which the obstacle protrudes from the inner wall in the direction of the interior of the chute, and a second position in which Obstacle does not protrude beyond the inner wall towards the interior of the chute, is adjustable.

The first stripping element and / or the second stripping element and / or the scraper can be designed as a spatula blade, as a spatula, or as a rod, in particular a round rod.

The first stripping element and / or the second stripping element and / or the flexible stripping element can also be designed as a rope, in particular a wire rope, as a wire, as a band or as a chain.

Since a rod, in particular a round rod, a rope, a wire or a band has a comparatively small surface area, the likelihood that larger solid adhesions form on it is reduced.

Preferably, the chute is tapered in the direction of the particle from top to bottom in cross section.

The chute can be cylindrical, conical, cube-shaped, regular or irregular polygon, or wedge-shaped.

The chute in the region of the inlet and in the region of the outlet have cross sections of different shape.

The cross sections of different shapes may be selected from circular, elliptical, square, rectangular, a shape of a regular or irregular polygon, and a shape consisting of composite arc segments.

The chute can be designed in several parts, with a plurality of walls, each forming an inner wall of the chute.

The chute can have a substantially concave shape.

The at least one inner wall, preferably all inner walls of the chute can be stripped at least once in two minutes, in particular once a minute.

Preferably, a tempering device may further be provided for tempering the at least one inner wall to a temperature which is below a threshold for the curing of the binder, preferably below 70 ° C.

In a preferred development, the first cleaning device can have at least one spatula which is set up to move relative to the at least one inner wall and the second cleaning device has a flexible stripping element which is stretched over the at least one inner wall in the travel path of the spatula.

As a further solution is a device for the gluing of particles, which consist at least partially of suitable for the production of material plates fibers and / or chips, wherein the device comprises a chute assembly.

The apparatus may further comprise a supply means for feeding the particles and a plurality of nozzles for discharging a binder, the nozzles being arranged in an area inside the chute and / or above an inlet opening of the chute.

More preferably, the device has a mixing device downstream of the chute arrangement.

Fig. 1

zeigt schematisch eine Vorrichtung zur Beleimung von Partikeln;

Fig. 2A

zeigt in einer schematischen Draufsicht eine Fallschachtanordnung gemäß einer ersten Ausführungsform der vorliegenden Erfindung;

Fig. 2B

stellt eine schematische seitliche Querschittsansicht der Fallschachtanordnung der Fig. 2A dar;

Fig. 2C

stellt eine schematische seitliche Querschittsansicht der Fallschachtanordnung der Fig. 2A in einer Variante dar;

Fig. 2D

stellt eine schematische Draufsicht der Fallschachtanordnung der Fig. 2A in einer weiteren Variante dar;

Fig. 3A

zeigt in einer schematischen Draufsicht eine Fallschachtanordnung gemäß einer zweiten Ausführungsform der vorliegenden Erfindung;

Fig. 3B

zeigt die Fallschachtanordnung der Fig. 3A in einem Zustand mit verstellten Wandungen;

Fig. 3C

zeigt in einer schematischen Draufsicht eine Fallschachtanordnung gemäß einer zweiten Ausführungsform der vorliegenden Erfindung;

Fig. 3D

stellt eine schematische Draufsicht der Fallschachtanordnung der Fig. 3A dar;

Fig. 4

zeigt in einer schematischen seitlichen Querschittsansicht eine Fallschachtanordnung gemäß einer dritten Ausführungsform der vorliegenden Erfindung;

Fig. 5

zeigt in einer schematischen seitlichen Querschittsansicht eine Fallschachtanordnung gemäß einer vierten Ausführungsform der vorliegenden Erfindung;

Fig. 6A

zeigt in einer schematischen seitlichen Querschittsansicht eine Fallschachtanordnung gemäß einer fünften Ausführungsform der vorliegenden Erfindung;

Fig. 6B

stellt eine schematische Draufsicht der Fallschachtanordnung der Fig. 6A dar;

Fig. 6C und 6D

zeigen schematisch eine erste Variante der Fallschachtanordnung der Fig. 6A und 6B;

Fig. 6E

zeigt schematisch eine weitere Variante der Fallschachtanordnung der Fig. 6A und 6B;

Fig. 6F

zeigt eine beispielhafte Ausgestaltung einer zweiten Reinigungseinheit;

Fig. 6G und 6H

zeigen schematisch eine nochmals weitere Variante der Fallschachtanordnung der Fig. 6A und 6B; und

Fig. 6G und 6H

zeigen schematisch eine wiederum weitere Variante der Fallschachtanordnung der Fig. 6A und 6B.

Embodiments of the invention are illustrated below with reference to the drawings:

Fig. 1

shows schematically a device for the gluing of particles;

Fig. 2A

shows a schematic plan view of a chute arrangement according to a first embodiment of the present invention;

Fig. 2B

FIG. 12 is a schematic lateral cross-sectional view of the chute assembly of FIG Fig. 2A group;

Fig. 2C

FIG. 12 is a schematic lateral cross-sectional view of the chute assembly of FIG Fig. 2A in a variant;

Fig. 2D

FIG. 12 is a schematic plan view of the chute assembly of FIG Fig. 2A in a further variant;

Fig. 3A

shows a schematic plan view of a chute arrangement according to a second embodiment of the present invention;

Fig. 3B

shows the chute arrangement of Fig. 3A in a condition with distorted walls;

Fig. 3C

shows a schematic plan view of a chute arrangement according to a second embodiment of the present invention;

Fig. 3D

FIG. 12 is a schematic plan view of the chute assembly of FIG Fig. 3A group;

Fig. 4

shows in a schematic lateral cross-sectional view of a chute assembly according to a third embodiment of the present invention;

Fig. 5

shows in a schematic lateral cross-sectional view of a chute assembly according to a fourth embodiment of the present invention;

Fig. 6A

shows in a schematic lateral cross-sectional view of a chute assembly according to a fifth embodiment of the present invention;

Fig. 6B

FIG. 12 is a schematic plan view of the chute assembly of FIG Fig. 6A group;

Figs. 6C and 6D

schematically show a first variant of the chute arrangement of FIGS. 6A and 6B ;

Fig. 6E

schematically shows a further variant of the chute arrangement of FIGS. 6A and 6B ;

Fig. 6F

shows an exemplary embodiment of a second cleaning unit;

Figs. 6G and 6H

schematically show a further variant of the chute arrangement of FIGS. 6A and 6B ; and

Figs. 6G and 6H

schematically show a turn variant of the chute arrangement of FIGS. 6A and 6B ,

In the following, due to the extensive examples, reference numerals 21x, 23x, 24x, 31x, 32x, 33x, 34x, introduced as an indication of multipartite, will be denoted by a to d instead of x.

In FIG. 1 is a schematic view of a device for the gluing of particles beginning with the metering device 2 and ending with a mixing device 7 in a general representation. In between, a chute 3 and a chute arrangement 10 to be described in more detail below are arranged. The particles are introduced as a particle stream 1 into the metering device 2, usually from a particle bunker by means of discharge devices, weighed there and introduced into the chute 4 for metering via a standard belt control (not shown). There, the particle stream or the particles 1 impinges on a dissolving device 3 and is there dissolved to a particle curtain 5 and / or divided.

The opening device 3 can in particular rake and / or baffles, spoke rollers (consisting of at least two discs having a radial distance to the axis of rotation (with or without a continuous shaft) rods, tubes or the like arranged parallel to the axis of rotation) and / or opening rollers, preferably designed as spiked rollers have.

The dissolved particle curtain 5 is then sprayed by means of suitable nozzles 6 with a binder and glued.

In the course of the particle curtain 5 falls through the chute assembly 10 and then passes into the chute assembly 10 downstream mixing device 7, in which by means of a rotating shaft 9 driven by mixing tools 8 the glued particles mechanically mix again and finally spend as a mixed particle flow (discharge arrow) ,

The glued particle stream is then stored in a dosing hopper or directly into a spreader to form a grit mat, which can be pressed in a further press in a press to a material plate and / or cured, introduced.

In principle, the chute arrangement 10 should have a sufficient drop height so that the binder can bond sufficiently strongly to the particles and should preferably be formed in the direction of fall at least half as long as the chute 4.

As shown, the chute 4 and the chute assembly 10 may be provided as separate devices. Alternatively, it is also possible that the chute 4 forms a unit with a chute of the chute assembly 10.

With reference to the FIGS. 2A to 6J Now, various embodiments of a chute assembly will be described, which is used as a chute assembly 10 in the apparatus of FIG. 1 is usable.

A first embodiment of a chute assembly 20 is shown in FIGS FIGS. 2a to 2c shown.

The FIGS. 2A to 2C represent a chute assembly 20 with a chute 21. The chute 21 has a rectangular cross-section, wherein four walls or wall elements each define an inner wall 21a, ..., 21d of the chute 21. Between each two inner walls 21a, ..., 21d, or the respective inner walls having walls or wall elements, respectively, a gap is formed through which at least one support member 23a, ..., 23d is arranged.

The support elements 23a,..., 23d are each assigned to an inner wall 21a,..., 21d and arranged to be displaceable along a direction substantially parallel to the surface thereof. At one end portion of each support member 23a, ..., 23d, a scraper member 22a, ..., 22d is disposed.

The support members 23a, ..., 23d and the stripping elements 22a, ..., 22d represent first cleaning means for cleaning the associated inner walls 21a ... 21d of the chute, wherein the cleaning of an inner wall 21a, ..., 21d takes place in that the associated support element is displaced in a direction parallel to the respective inner wall 21a, ..., 21d, so that the stripping element 22a, ..., 22d brushes against the inner wall 21a, ..., 21d and applies it to this Purifies and cleans of any binder or particles 1, which have deposited on this.

The stripping elements 22a, ..., 22d can be designed as a spatula blade, as a spatula, as a rod, in particular round rod, as a rope, as a wire, as a band, as a chain, as a brush or in any other suitable form.

The support elements 23a, ..., 23d may be formed, for example, as elongated sheets, as in the FIG. 2b represented, for example, in each case two sheets 23a arranged one above the other in parallel and the stripping element 22a is arranged on the two sheets 23a.

It is possible as well as in Figure 2C illustrated, the support members 23a, ..., 23d each form a wall, which extend in height substantially over the stripped area of the respective associated inner wall 21a, ..., 21d.

Other embodiments of the support elements 23a, ..., 23d are also possible.

While the FIGS. 2A to 2C show a chute 21 with a rectangular cross-section, which extends in the direction of the particle in the direction of the particle in a straight line, this is not limiting. Thus, the chute 21, for example in the form of a reverse truncated pyramid, from top to bottom in the direction of the particle 1, be tapered.

Also other cross sections, for example in the form of regular or irregular polygons are possible. The inner walls 21a, ..., 21d can run in a horizontal line in a straight line, or can be concave with a curvature pointing inwards of the chute or convex with a curvature facing outward of the chute; In these cases, the support members may also be formed with corresponding curvatures, so that they follow when adjusting the curvature of the respective associated inner walls and it is ensured in this way that the stripping 21 a, ..., 21 d overlap the associated inner walls can clean.

During the process, the support elements 23a,..., 23d are moved past associated second cleaning devices 24a,..., 24d, which clean the support elements 23a,..., 23d.

The second cleaning means 24a, ..., 24d can be arranged in various ways, such as in the FIG. 2a shown. The second cleaning device thus cleans at least parts of the first cleaning device.

The second cleaning devices can be used as a side or an edge of an inner wall, or as stripping elements 24a,..., 24d, in particular as Spatula blade, as a spatula, as a rod, in particular round rod, as a rope, as a wire, as a band, as a chain or be designed in any other suitable form.

Thus, the second cleaning means (the scraper 24b) may be formed as a side or edge of an inner wall 21a, on which a support member 23 or other parts of the first cleaning device passes during sliding so as to be stripped and cleaned ( Fig. 2A , top right).

Similarly, as the second cleaning means on the side of an inner wall 21 d, a scraper 24 a may be arranged. If the carrying element 23a is offset, it strikes past the stripping element 24a with its surface facing the interior of the chute 21 and is thus stripped off and cleaned ( Fig. 2A , top left).

Likewise, it is possible as a second cleaning device to form the stripping element 24c at one end of one of the support elements 23b. When the support member 23b is fully moved toward the inside of the chute 21, the scraper 24c comes into contact with the side of the support member 23c facing the inside of the chute 21. If the carrying element 23c is displaced, it passes by the wiping element 24c and is thus stripped off and cleaned ( Fig. 2A , bottom right).

Finally, the wiping element 24d may also be arranged outside the chute 21, such that, when the carrying element 23d is displaced, it strikes the stripping element 24d with its surface facing the interior of the chute 21 and in this way is stripped off and cleaned ( Fig. 2A , bottom left).

It can be after FIG. 2D In this case, it may be preferable for the support elements 23a,..., 23d to have a resilient design, so that the stripping element 22a arranged at the end of a support element 23a is pressed against the inner wall 21a by the action of the resilient force. If the carrying element 23a is offset, therefore, even in the case of a curved inner wall, the wiping element 22a can safely pass along and strip over the curved inner wall 21a to strip and clean them.

So it can, as in the example of FIG. 2D shown sufficient to form the chute 21 with a substantially circular or elliptical cross-section, with a single wall having an inner wall 21a. Through a gap between the two ends of the wall, the support member 23 a is guided into the interior of the chute 21 into it. The wall may be curved in the form of a spiral, so that the two ends of the wall overlap, thus the wall circumscribes an angle greater than 360 °. Between the ends of the gap is formed, through which the support member 23 a is guided.

The support member 23a may be formed as a resilient wall whose height substantially corresponds to the height of the stripped region of the inner wall 21a of the chute 21.

If at least two preferably narrow support elements 23a are used, at the end of which a preferably rigid stripping element 22a, such as a round rod, is arranged, it is also possible to design the fall shaft 21a as tapering from top to bottom in the fall direction of the particles, in particular in FIG Shape of an inverted truncated cone. It is preferred that for each support member 23 a separate drive (not shown) is provided, wherein the drives are controlled to offset the support members 23 a so that the stripping element 22 a with substantially constant vertical orientation along the inner wall 21 a of the chute 21 is moved. Analogous to FIG. 2A In the example, the second cleaning device is arranged separately outside the chute 21 as a stripping element 24d.

With reference to the FIGS. 3A and 3B Now, a chute assembly 30 according to a second embodiment will be described.

The chute arrangement 30 has a chute 31, which is formed from a plurality of wall elements, each having an inner wall 31a, ..., 31d, which are curved according to a substantially arcuate shape, in particular a circular arc shape or elliptical arc shape.

The total sum of angles included in the arcuate wall elements corresponds at least to an angle of 360 ° + the angle encompassed by the longest wall element.

Like in the FIG. 3A To recognize, the wall elements partially overlap, such that a wall element with an inner wall 31a an adjacent wall element with an inner wall 31 b overlaps outside, and is overlapped by another adjacent wall element with an inner wall 31 d outside.

On each wall element, a scraper element 32a, ..., 32d is arranged, in such a way, to overlap the respective outer inner wall 31a, ..., 31d of the associated, adjacent wall element.

As indicated by the arrows, each of the wall elements can be adjusted or moved, so that the wall element can be rotated in particular about a center associated with the arc. This is exemplary in the FIG. 3B shown. In this way, for example, the inner walls 31a and 31b can be offset relative to each other, so that the stripping element 32b strikes over the inner wall 31a and cleans it.

For the inner wall 31a, therefore, the wall member 31b and the scraper member 31b constitute a first cleaning means which cleans the inner wall 31a. The wall element 31c and the stripping element 32c in turn constitute a second cleaning device, which cleans the inner wall 32b and thus the first cleaning device.

In a third embodiment, in the FIG. 4 is shown, a chute assembly 40 has a chute 41 in which in a known manner at least one scraper blade or scraper 42 is arranged as a first cleaning means to strip the inner wall 41a. It can be the chute 41 relative to Scraper 42 and / or the scraper 42 moves relative to the chute 41, in particular be rotated about a rotation axis.

The chute arrangement 40 further has a second cleaning device in the form of at least one doctor blade or scraper 44, which can be adjusted by means of an electromotively, hydraulically or pneumatically actuatable feed axis as drive means 43 from a rest position along an axis substantially parallel to the scraper 42, in such strip the scraper 42 and clean in this way.

In the case of a movable scraper 42 can be provided that the scraper 42 is first moved to a cleaning position and is stopped in this, before the scraper 44 is moved from the rest position.

In addition, as in the FIG. 4 represented a hopper 45 may be provided which need not be part of the chute assembly 10 needs. The hopper 45 forms, together with the inner wall 41 a of the chute 41, a gap through which the scraper 42 can be guided into the interior of the chute 41. The hopper 45 may further provide protection against fouling by the sizing agent and / or glued particles 1. In this gap could be introduced to keep the chute 41 clean and a coat of air or no longer sticky, but already glued particles.

In a fourth embodiment, in the FIG. 5 is shown, a chute assembly 50 on a chute 51.

The chute arrangement 50 also has a first cleaning device in the form of at least one scraper blade or scraper 52, which adjusts by means of an electric motor, hydraulically or pneumatically actuable feed axis as drive means 53 from a rest position indicated by dashed lines along an axis substantially parallel to the inner wall 51 a can be, so as to strip the inner wall 51a and clean in this way.

The chute arrangement 50 also has a second cleaning device, which is preferably in the form of at least one scraper blade or scraper 54, which is moved by means of an electromotively, hydraulically or pneumatically actuatable feed axis 55 as drive means from a rest position over the scraper 52 positioned in the rest position can, in this way, strip the scraper 52 and clean in this way.

Instead of a scraper blade or a scraper 54, another suitable stripping device can be used as a cleaning device. Moreover, if the scraper 54 or the other suitable stripping device is arranged such that the scraper blade or the scraper 52 drives past it from the chute 51 when moving out of the chute 51, a drive means 55 can also be dispensed with.

In a fifth embodiment, a chute assembly 60 includes a flexible stripping member 62 as the first cleaning means, as in FIGS FIGS. 6A to 6J shown.

As in the Figures 6A and 6B shown, in this embodiment, the chute 61 may be configured rotationally symmetrical, in particular conical, with a wall defining an inner wall 61a. The wall of the chute can be arcuately curved, so that the chute 61 tapers in the direction of the particle from top to bottom.

In this embodiment, the first cleaning device may have a flexible stripping element 62, in particular an endless rope, preferably designed as a wire rope.

The endless cable is guided and held by a deflection means 63, here a deflection roller, in such a way that it encloses the wall of the chute 61 so that the cable runs both in the chute 61 adjacent to the inner wall 61a and outside the chute 61.

The pulley may be associated with a drive (not shown) to move over the pulley the rope in the direction of extension of the endless rope in motion offset. The movement may be an intermittent or continuous circumferential movement of the rope, or an oscillating reciprocation of the rope, or a combination thereof.

In order to generate a relative movement between the stripping element 62 and the chute 61 or its inner wall 61a so that the cable moves tangentially to the inner wall 61a in order to strip it, the chute 61 can be moved by suitable drive means (not shown), in particular about an axis of rotation be rotated, and / or there may be provided guide means to which the deflection means 63 are associated, as in more detail with respect to the Figures 6C and 6D will be described.

In order to prevent the glue from forming on the rope adhesions or glued particles 1 which could agglomerate, a second cleaning device with scraper element 66 is provided for cleaning the rope and arranged so that the rope passes by or passes therethrough.

This second cleaning device may be formed, for example, as a brush, doctor blade, or as a scraping edge, where the rope is moved past, or as a stripping gap or as a stripping cylinder, through which the rope passes. The second cleaning device can also be configured as a fluid bath which is filled, for example, with water and / or a cleaning agent and through which the wiping element 62 is guided in order to wash off and remove sizing agent and / or particles 1 therefrom.

On account of the curved or concave shape of the chute 61 pointing towards the interior of the chute 61, in which the wall can be cambered in particular, there is the advantageous effect of laying the rope against the inner wall 61a of the chute 61 for a particularly good support comes and adapts due to its flexibility of the shape of the inner wall 61a. As a result, a particularly secure cleaning of the inner wall 61a of the chute 61 can be achieved.

To further enhance this effect, additional clamping means 64, 65 may be provided, which in the FIG. 6A exemplified as a spring and a pinch roller to tension the rope.

The flexibility of the rope as a stripping element 62 also allows the rope to conform to different cross sections of the chute 61, such as a rectangular cross-section having a large opening width in the inlet region and a substantially smaller circular cross-section in the outlet region, such as in Figs Figures 6C and 6D shown.

As in the Figures 6C and 6D illustrated, the chute 61 may be configured in several parts, for example, with four walls that define the four inner walls 61a to 61 d. In the region of the inlet, the chute 61 has a rectangular cross section, while the chute 61 is formed in the region of the outlet with a circular cross section. The walls of the chute are arcuately curved, so that the chute 61 tapers in the direction of the particle 1 from top to bottom.

As in the example of Figures 6A and 6B is also in the example of Figures 6C and 6D the stripping element 62 is guided and held as a cable via a deflecting means 63 so that it encloses a wall of the chute, so that the cable extends both in the chute 61 adjacent to an inner wall 61 d and outside of the chute 61. Different for example from the FIG. 6A are in the example of FIG. 6C in the lower end region of the chute 61, the walls are each formed with a bead or arc portion as a deflection means 67 for the rope, which serves to deflect the rope and hold. The bead can therefore be considered as a guide device and as a deflection device.

The deflecting means 63 is associated with a guide means comprising an endless guide member 69, such as a chain, and guide means 68, such as gears. As in particular in FIG. 6D shown, the guide means 68 are arranged so that they span the circulating chain so that it rotates the chute 61.

The examples mentioned are not restrictive and it can be used as a guide element 69, a rope, in particular a steel cable, a band, a wire or the like. As guide means 68 and rollers, slides or other elements can be used, which are adapted to hold the corresponding guide means and to guide accordingly and to redirect as needed.

A motor (not shown) may be connected to one of the guide means 68 for driving and moving the chain as a guide member 69. Since the pulley is connected to the chain 62 of the guide means, the flexible, endless scraper or rope is thus caused to move in a direction tangential to the surface of the inner wall 61 d. In this way, the rope, the inner wall 61d, or all the inner walls 61a, ..., 61 d of the chute 61 to overlap and clean them by any binder, or glued particles 1, which on the inner walls 61a, ..., 61 d attached, be stripped off.

The second cleaning device as a stripping element 66 may be installed in a predetermined, fixed location to clean the rope when it is moved by the guide means and associated drive means in a corresponding cleaning position. The cleaning device may also be associated with a guide device and move along in order to follow the movement of the cable via the inner walls 61a to 61d of the chute 61.

While in the FIGS. 6A to 6D the endless rope enclosing a wall, it is in an in FIG. 6E illustrated modification also possible to guide the endless rope over a deflection 72 so that the endless rope as stripping element 62 extends within the chute 61, so that the leading and returning portion of the rope both come into contact against the inner wall 61 d of the chute 61 , Such guidance of the rope has the advantageous effect of a smaller space requirement, since no clearance for the outside of the chute 61 extending portion of the rope is required. In addition, the inner wall 61 d is twice scrapped by the double-running rope, resulting in a better cleaning performance.

The second cleaning device is in the example of FIG. 6E executed as a scraper edge 71, at which the rope is passed to strip this.

In one in the FIGS. 6E and 6F 2, the second cleaning device may be designed as an obstacle 75 that can be introduced as a stripping element 62 in the travel path 74 of the cable, which is preferably arranged in a wall of the chute 61 having at least one inner wall 61 a... 61 d, wherein the insertable obstacle 75 between a first position in which the obstacle protrudes from the inner wall 61a ... 61d toward the interior of the chute 61, and a second position in which the obstacle does not project beyond the inner wall 61a ... 61d can be. The insertable obstacle 75 can be adjusted, for example pneumatically, hydraulically or by electric motor and can be formed for example as a mandrel or cone. In this aspect, the travel path 74 is for better understanding Fig. 6E illustrated.

When the insertable obstacle 75 is introduced, it opposes the movement of the rope. The rope is thereby tensioned until it "snaps past" the obstacle 75 or until the rope is released by adjusting the obstacle 75. The thus tensioned rope relaxes in a sudden movement which can cause the rope to vibrate and "shake" and / or strike the inner wall 61a, ..., 61d, causing gluing agents and / or particles 1 deposited on the rope Rope dropped, can be shaken off. It is preferred that the direction of movement of the rope can be reversed to move the rope from both directions against the adjustable obstacle 75.

The Figures 6G and 6H show a further variant in which a rope is attached to two winding devices 73, which can wind up and unwind the rope. By appropriate control of a drive (not shown) of the winding devices 73, the rope can be offset in a reciprocating motion in the longitudinal direction of the rope.

The Figures 6G and 6H further show guide means, which may be formed, for example, as Zustellachsen or rails 76, to which the winding means 73 are attached, for example by means of a carriage or a slider (not shown) traveling in the track rail 76. In the FIG. 6H By way of example, rails 76 are shown which guide and hold the winding devices 73 and, via the winding devices 73, the cable which circulates around them. By means of the rails 76, therefore, the cable can be moved over the surface of the inner wall 61d away.

For the other inner walls of the chute 61 each slide rails 76 may also be provided on which winding devices are arranged, which corresponding ropes are assigned; Because of the clarity of the presentation was in the Figures 6G and 6H waived their representation. Alternatively, the running rail 76 corresponding to the chute 61 arcuate and circumferential running.

With reference to the FIGS. 6A to 6H Examples have been given in which a flexible stripping element 62, like a rope, extends in a substantially vertical direction in the region of an inner wall 61a, ..., 61d. However, this is not limiting, and as in the Figures 6I and 6J shown example, the chute assembly 60 may also be formed so that a flexible stripping element 62 adjacent to an inner wall 61a, ..., 61 d of the chute 61 extends in a substantially horizontal direction, for example as an endless rope, the deflection means 63rd to be led.

For each inner wall 61a, ..., 61d of the chute 61, a flexible stripping element 62 is preferably provided, which can be designed, for example, as an endless cable, which is arranged in such a way, the respective inner wall 61a, ..., 61d include, as in the FIG. 6I is shown on the example of the inner wall 61d.

The inner walls 61a, ..., 61d of the chute 61 may extend in a substantially rectilinear manner in the horizontal direction, or may be concave, in particular cambered, so that they are bent in the direction of the interior of the chute 61, as in FIG FIG. 6I shown on the example of the inner wall 61 b.

The deflection means 63 are associated with respective guide means (not shown) which may be arranged to turn the deflection means 63 in one in the To move essentially vertical direction, as indicated by the arrows of the FIG. 6J indicated, so that the stripping element 62 of the extension of the inner wall 61 d of the chute is moved in a substantially vertical direction tangential to the surface of the inner wall 61 d and strips it in a substantially vertical direction. In this case, the movement axis can be aligned in a suitable manner substantially perpendicularly, essentially following the course of the lateral edge of the inner wall 61 d, or in another suitable manner.

As guide means band or cables may be provided, similar to those with respect to the FIGS. 6A to 6H described.

It is also possible, the guide means as Zustellachsen or as guides, in particular linear guides to design, the Umlenmittel 63 are each attached to a running in the guide carriage (not shown), which is actuated by electric motor, pneumatic or hydraulic.

While the invention has been described by way of example of preferred embodiments, these are not limiting. Thus, various aspects of the various embodiments may be combined or interchanged. In particular, different forms of first and / or second cleaning devices can be combined in a chute arrangement. Likewise, various types of stripping members 62 or guide means may be combined.

Also, the guide means are not limited to the examples described. Thus, instead of the guide means described, for example, as guides, in particular linear guides, designed guide means are provided which have a running in the guide carriage (not shown), which is actuated by electric motor, pneumatic or hydraulic.

Also, guide means may be used which are in the form of a slide rail on which a scraper member is slidably held by, for example, a sliding member or roller disposed in the rail. While examples have been given in which the stripping element 62 is moved relative to an inner wall 61a, ..., 61d of the chute 61 by means of the first and second guide means, this is not limitative, and it is also possible to fit the chute itself by suitable means Drive means to move. Thus, for example, the chute 61 may be designed rotationally symmetrical and be offset by corresponding drive means in a rotational movement, so that the inner wall of the chute 61 moves with respect to the stripping element 62. The stripping element 62 can be held stationary by corresponding first and second guide means while the inner wall moves past the stripping element 62. It is also possible to combine a movable stripping element 62 with a movable chute 61.

The guide devices can be arranged both outside and inside the space defined by the chute 61. Preferably, when the guide means are disposed within the chute 61, covers may be provided to protect the guide means from fouling and / or additional stripping means which may be disposed on the flexible stripping member, for example, to straddle the guide means located within the chute and to clean so.

Furthermore, the chute arrangement can have a tempering device for tempering one or more inner walls to a temperature which is below a threshold for the curing of the binder, preferably below 70 ° C. (1443) List of Reference P1443: 1 particle 44 scraper 2 metering 45 hopper 3 dissolver 4 chute 50 Chute arrangement 5 particle curtain 51 chute 6 jet 51 a inner wall 7 mixing device 52 scraper 8th Mixing tools 53 drive means 9 wave 54 scraper 10 Chute arrangement 55 drive means 20 Chute arrangement 60 Chute arrangement 21 chute 61 chute 21x, a, b, c, d inner wall 61x, a, b, c, d inner wall 22 stripping element 62 stripping element 23 supporting member 63 deflecting 24 guide element 64 clamping means 65 clamping means 30 Chute arrangement 66 stripping element 31 chute 67 deflecting 31x, a, b, c, d inner wall 68 guide means 32 stripping element 69 guide element 71 stripping 40 Chute arrangement 72 deflecting 41 chute 73 winding device 41x, a, b, c, d inner wall 74 traverse 42 scraper 75 obstacle 43 drive means 76 runner

Claims (23)

1. A free-fall shaft arrangement (10; 20; 30; 40; 50; 60), especially for an apparatus for gluing particles (1) which at least to some extent consist of fibres and/or chips suitable for producing material boards, wherein the free-fall shaft arrangement (10; 20; 30; 40; 50; 60) comprises a free-fall shaft (21; 31; 41; 51; 61) having an inlet for the feed of the particles (1) and an outlet for the discharge of the particles (1), and at least one first cleaning device for cleaning at least one inner wall (21 a ... 21 d) of the free-fall shaft (21; 31; 41; 51; 61), characterized in that the free-fall shaft arrangement (10; 20; 30; 40; 50; 60) further comprises at least one second cleaning device for cleaning the at least one first cleaning device.
2. A free-fall shaft arrangement (20; 30) according to claim 1, characterized in that the first cleaning device is formed as at least one movable support element (23x; 31x), which is movably arranged relative and especially parallel to an associated first inner wall (21x; 31x) of the free-fall shaft (21; 31), wherein at least one first stripping element (22x; 32x) is arranged or formed on the movable support element (23x; 31 x), such that the associated inner wall (21x; 31x) is stripped off when the movable support element (23x; 31x) is displaced.
3. A free-fall shaft arrangement (20; 30) according to claim 2, characterized in that the movable support element (23x; 31x) is arranged to pass through a gap which is formed between two adjoining inner walls (21x) or between two ends of an inner wall (21 x).
4. A free-fall shaft arrangement (20; 30) according to one of the claims 2 to 3, characterized in that the movable support element (23x; 31 x) is formed as a wall having a height which corresponds to the height of the associated inner wall (21x; 31 x) to be stripped, wherein the movable support element (23x; 31 x) is preferably formed in a resilient manner.
5. A free-fall shaft arrangement (20) according to one of the claims 2 to 4, characterized in that the second cleaning device comprises at least one second stripping element (24x), wherein especially the second stripping element (24x) is arranged on a wall or a support element (23x).
6. A free-fall shaft arrangement (30) according to one of the claims 2 to 4, characterized in that the movable support element is formed as a wall element of the free-fall shaft (31) which forms an inner wall (31 x) of the free-fall shaft (31).
7. A free-fall shaft arrangement (30) according to claim 6, characterized in that the free-fall shaft (31) comprises several wall elements which are each formed in a curved manner, wherein each wall element partly overlaps another wall element on its exterior side.
8. A free-fall shaft arrangement (40) according to claim 1, characterized in that the first cleaning device comprises at least one first scraper (42) which is associated with the at least one inner wall (41 a), and the second cleaning device comprises at least one second scraper (44) and drive means (43) for moving the second scraper (44) from an idle position along an axis substantially parallel to the first scraper (42), such that the first scraper (42) is stripped off.
9. A free-fall shaft arrangement (50) according to claim 1, characterized in that the first cleaning device comprises at least one first scraper (52) and drive means (53) for moving the first scraper (52) from an idle position along an axis which is substantially parallel to the at least one inner wall (51 a), such that the first inner wall (51 a) is stripped off, and the second cleaning device comprises at least one second scraper (54) and drive means (55) for moving the second scraper (44) from an idle position over the first scraper (52) positioned in the idle position, such that the first scraper (52) is stripped off.
10. A free-fall shaft arrangement (60) according to claim 1, characterized in that the first cleaning device comprises at least one flexible stripping element (62), especially an endless stripping element (62), for cleaning the at least one inner wall (61x).
11. A free-fall shaft arrangement (60) according to claim 10, characterized in that the free-fall shaft arrangement (60) further comprises a first guide device and a second guide device, wherein the first guide device and the second guide device are designed to retain and guide the at least one stripping element (62), such that a relative movement is allowed in the tangential direction to the at least one inner wall (61x) between the stripping element (62) and the at least one inner wall (61 x) of the free-fall shaft (61), wherein further drive means are provided which are set up to act on the free-fall shaft (61), the first guide device, the second guide device and/or the at least one stripping element (62) for generating the relative movement.
12. A free-fall shaft arrangement (60) according to claim 11, characterized in that the first and/or the second guide device comprises:

    a plurality of guide means (68), especially guide rollers or guide gearwheels, and

    an endless guide element (69), especially an endless guide cable, an endless guide belt, an endless guide wire or an endless guide chain, which extend around the guide means (68), wherein the at least one flexible stripping element (62) is fastened to the endless guide element (69) directly or via holding means and/or deflecting means (63, 72).
13. A free-fall shaft arrangement (60) according to one of the claims 10 to 12, characterized in that the endless stripping element (62) is arranged by means of deflecting means (63, 67) in such a way that it encloses a wall element of the free-fall shaft (61) having the at least one inner wall (61 x), wherein especially the endless stripping element (62) is arranged in such a way that it is arranged to extend in the region of the inner wall (61 x) within the free-fall shaft (61).
14. A free-fall shaft arrangement (60) according to one of the claims 10 to 13, characterized in that drive means are provided which are designed to set the at least one flexible stripping element (62) into a reciprocating motion in the direction of the longitudinal extension of the stripping element (62).
15. A free-fall shaft arrangement (60) according to one of the claims 10 to 14, characterized in that two winding devices (73) are provided, wherein the flexible stripping element (62) is connected to the winding devices (73) in order to allow being wound up on the winding devices (73) or unwound therefrom.
16. A free-fall shaft arrangement (60) according to one of the claims 10 to 14, characterized in that drive means are provided which are designed to set the endless stripping element (62) into a revolving motion.
17. A free-fall shaft arrangement (60) according to one of the claims 10 to 16, characterized in that the at least one endless stripping element (62) extends adjacent to the at least one inner wall (61 x) of the free-fall shaft (61) in a substantially horizontal direction.
18. A free-fall shaft arrangement (60) according to one of the claims 10 to 17, characterized in that the at least one endless stripping element (62) extends adjacent to the at least one inner wall (61 x) of the free-fall shaft (61) in a substantially vertical direction and/or in a vertical direction according to a shape of the free-fall shaft (21; 31; 41; 51; 61).
19. A free-fall shaft arrangement (60) according to one of the preceding claims, characterized in that further tensioning means (64, 65) are provided, which are designed to act on the first guide device and/or the second guide device and/or the at least one stripping element (62) in such a way that the at least one stripping element (62) is held under tension.
20. A free-fall shaft arrangement (60) according to one of the claims 10 to 19, characterized in that the stripping element (62) is guided to extend past the second cleaning device or through the cleaning device.
21. A free-fall shaft arrangement (60) according to claim 20, characterized in that the second cleaning device is formed as a fluid bath, a brush, a stripping edge, or a stripping cylinder, or as an obstruction (75) which is arranged in or can be introduced into the path of displacement (74) of the at least one stripping element (62), wherein the introducible obstruction is arranged in an especially preferred manner in a wall of the free-fall shaft (61) which comprises an inner wall (61x), wherein the introducible obstruction (75) is adjustable between a first position in which the obstruction protrudes from the inner wall (61 x) in the direction of the interior of the free-fall shaft (61) and a second position in which the obstruction (75) does not protrude beyond the inner wall (61x) in the direction of the interior of the free-fall shaft (61).
22. A free-fall shaft arrangement (10; 20; 30; 40; 50; 60) according to one of the claims 2 to 21, characterized in that the first stripping element (22x; 32x) and/or the second stripping element (24x; 32x) and/or the scraper (42, 44) is formed as a spatula blade, a spatula or a rod, especially a round rod.
23. A free-fall shaft arrangement (10; 20; 30; 40; 50; 60) according to one of the claims 2 to 21, characterized in that the first stripping element (22x; 32x) and/or the second stripping element (24x; 32x) and/or the flexible stripping element (62) is formed as a cable, especially a wire cable, as a wire, a belt or a chain.

Images