EP0376918B1 - Method and apparatus for manufacturing lamellar wood from sawn timber - Google Patents

Description

The invention relates to a method and a device for producing wooden slats from sawn timber. In the present context, wooden slats are to be understood as relatively thin wooden boards that are thicker than 2 to 3 mm and are processed into high-quality single- and multi-layered products, such as multi-layered natural wood panels, glue binders, glued plywood, window scantlings, solid wood panels and the like. Like ..

According to the prior art, such wood lamellas are usually produced by first drying the sawn timber to a relatively low level of moisture and then cutting the timber planks using band saws and the like. Like. are sawn into the individual wooden slats. Such a method has several disadvantages. On the one hand, the quality of the wood lamellae produced in this way leaves something to be desired, since the wood lamellae slightly fray or fray during the sawing process, particularly in the area of branches and edges, and the drier the sawn timber is, the more so. This results in a relatively high proportion of rejects.

Another disadvantage of the known method is the relatively poor yield, ie the proportion of waste is relatively high. This is because everyone Saw cut Waste is generated that corresponds to the thickness of the saw cut. If, for example, wood slats with a thickness of 4 mm are produced and the saw cut width is 2.5 mm, this results in a waste of about 40% of the sawn timber material.

Another disadvantage of the method according to the prior art is that a relatively large amount of energy is consumed in the production of the wood lamellae. This is due to the fact that, due to the relatively wide kerf of the saw cut, a lot of material has to be cut.

On the other hand, it is known to produce wooden lamellae in a cutting device by means of saw-less cutting. However, the results that have thus far been achieved are also unsatisfactory. Although the yield is increased here on the one hand by avoiding the saw cut, on the other hand a so-called residual lamella occurs in this method, i. H. after cutting off the maximum number of wooden slats with the required nominal thickness that can be cut out of the sawn timber plank, a remainder remains that is less thick than the nominal thickness of the wooden slats to be manufactured and therefore cannot be reused, at least not in the respective production process.

Furthermore, the quality of the wooden slats produced in this way leaves much to be desired, especially since the individual wooden slats leave the cutting device in a severely wounded condition, which can be attributed to the fact that the wooden slats cut from the timber plank are led away obliquely to their original transport direction. In the known cutting device thus the problem that has not yet been solved, to return such twisted wooden slats to their non-twisted, flat or plan state with reasonable effort.

In a method for producing lumber known from DE-A 21 24 086, a veneer is peeled off from a possibly damped tree trunk by means of a veneer lathe, then the peeled veneer roll is wound through a treatment station, in particular in the form of a salt bath, on a spool and then dried. The veneer is then cut to lengths of 2.4 by 1.2 meters in a cutting device, individual sheets are joined to form a laminate, and ultimately the laminate is sawn into individual boards, beams or the like, if necessary.

The invention is based on the object of specifying a method which delivers high-quality wood lamellae with justifiable outlay, at the same time achieving a maximum yield and furthermore keeping the required energy expenditure as low as possible. Furthermore, a device is to be created which meets the above-mentioned conditions.

This object is achieved according to the invention essentially by the combination of features according to claim 1, the method steps preferably being carried out continuously, so that the individual wooden lamellae run through the entire system automatically and continuously.

The process step of saw-chip-free cutting is preferably preceded by a process step that enables a cutting optimization in such a way that no residual lamellae occur. This preceding process step can consist in the preconditioning of the sawn timber, with a moisture of the sawn timber of about 40 to 60%, preferably about 50 %, tailored to the respective type of wood.

Alternatively or additionally, this upstream method step can consist in measuring the moisture of the sawn timber fed to the cutting station and in controlling the cutting parameters, such as in particular the contact pressure in the area of the cutting knife and / or the cutting thickness in accordance with the measured moisture. Tolerances that would otherwise lead to the appearance of residual lamellae can be compensated in this way.

The combination according to the invention of saw-less cutting / drying / machining post-processing, including, if appropriate, the process step preceding the cutting leads to the following advantages:
Wooden slats of the highest quality are produced. The visible surfaces of the board lamellae treated by grinding have a high surface quality, since fraying in the branch area, as in the case of the prior art, does not even occur to this extent here and is largely eliminated by the grinding process. Since the lumber is not dried down to a low level of moisture before processing, as in the known prior art, the wood remains intact in the branch areas when cutting.

The energy required to produce the wooden slats is lower than in the prior art. While in the prior art wood is cut to the width of the saw cut for each cut, in the case of the method according to the invention, material is only removed in a fraction of a millimeter due to the grinding process; there is no material in the cutting device itself machined. The sum of the energy required for cutting and subsequent post-treatment (grinding) is less than the energy required for sawing.

Due to the saw-less cutting of the wooden slats, practically no waste occurs in the cutting device. Since there is also only a comparatively small amount of waste when reworking the cut wood lamellae, the process according to the invention gives an excellent yield. This is further improved by the fact that such a cutting optimization is possible so that the so-called residual lamellae, which have the same tolerances as the other wooden lamellae and can therefore be used as well, can remain in the production process; or, in other words, residual lamellae can be completely avoided in the method according to the invention.

In the case of the method according to the invention, the use of materials compared to conventional methods is therefore decisive; this results in about 50% to 80% less waste, so that a correspondingly higher yield of the starting material takes place.

The method according to the invention permits lamella production that is much more gentle on the wood than conventional methods. For example, the otherwise occurring drying and. Machining cracks, particularly in the branches, have been largely eliminated or nonexistent.

With the method according to the invention, in which the wood lamellae are dried after the cutting, particularly uniform drying results are achieved down to achieved about 6% wood moisture and possibly even less. With the conventional technology, in which the wood is dried before cutting or sawing, further processing of the material with such low wood moisture is no longer possible in practice or only to a limited extent, ie with corresponding losses in quality. The drying of the wooden slats after cutting the sawn planks has the further advantage that less energy is consumed during the drying process, since on the one hand the waste generated in the prior art during sawing, such as sawdust and residual slats, is not co-dried and furthermore the thinner, already cut material is easier to dry than the much thicker starting material.

A further, decisive advantage of the drying process downstream of the cutting process is that in the temperature-controlled drying process, in which drying is carried out at a temperature of the order of about 160 °, the twisting of the wooden lamellae, which has arisen during the cutting process, can be reversed. so that completely flat, non-twisted board lamellae leave the dryer. This is the only prerequisite for economically viable uses of the known method of producing the wooden slats by means of a knife cut.

A further feature of the invention is based on the knowledge that when sawn-free cutting of the sawn timber by means of cutting knives, one of the two side surfaces of the wood lamella, namely that on the cutting side, has a lower surface quality than the other, after this side is evident on the surface in the cutting station Fibers are destroyed, which causes these in the following called "open" slat sides small cracks and the like. which reduce the surface quality of this open slat side. After a further process step according to the invention, the wood lamellae are therefore marked after the cutting process with regard to their underside facing the cutting knife and / or their top side facing away from the cutting knife, for example by means of an optical marking, so that it can be determined until the final processing of the wood lamellae into the end product. which side of the wooden slat is the open and which is the closed slat side. After this marking can be lost in the postprocessing process, the marking may have to be repeated after the postprocessing process. The marking on the wooden slats makes it possible to ensure that the visible surface or surfaces of the end product is always formed by the closed slat sides. This ensures a constant quality of the end products.

The post-processing device downstream of the drying device preferably comprises individually switchable components for the selective post-processing of the maximum of four side surfaces of the wooden slats running parallel to the feed direction. Such components are preferably formed by high-speed grinding machines, although in particular the narrow sides of the wooden lamellae can alternatively also be leveled and processed using high-speed milling units. If required, several components can also be connected in series. The components can be used for grinding, planing, milling and possibly also for profiling the wooden slats, for example for removing the edges. The individual connectivity of the individual components ensures that only those sides of the wooden slats are treated where this is technically necessary; For example, in the case of a multi-layer board, the inner surfaces of the wooden slats do not of course have to be sanded or only to a limited extent. The entire processing in the area of post-processing is tailored to the later use of the wooden slats, ie the processing machines are designed so that different surfaces or edges, depending on the setting, cannot be processed or can be processed several times within one pass.

• Fig.1 eine Draufsicht einer nach dem erfindungsgemäßen Verfahren arbeitenden Vorrichtung zur Herstellung von Holzlamellen aus Schnittholz,
• Fig. 2 eine schematische Seitenansicht der Sortiereinrichtung der Vorrichtung nach Figur 1,
• Fig. 3 eine Draufsicht auf einen Teil einer weiteren Ausführungsform einer erfindungsgemäßen Vorrichtung, und
• Fig. 4 eine teilweise schematisierte Seitenansicht der Konditioniereinrichtung der erfindungsgemäßen Vorrichtung.

Further advantageous features of the invention emerge from the remaining subclaims in connection with the following description, in which several exemplary embodiments of the invention are shown in more detail with reference to the drawing. The drawing shows in a schematic representation:

• 1 is a plan view of an apparatus for producing wooden lamellae from sawn timber, which works according to the method according to the invention,
• 2 shows a schematic side view of the sorting device of the device according to FIG. 1,
• 3 shows a plan view of part of a further embodiment of a device according to the invention, and
• Fig. 4 is a partially schematic side view of the conditioning device of the device according to the invention.

As shown in Fig. 1, in the case of the embodiment described here in the form of sawn timber, for. B. square timbers, boards, planks 2 etc. present cut goods first pre-dried or preconditioned in a conditioning device 4 in which the planks 2 are arranged in a stationary manner. The conditioning device 4 can be a lumber dryer, which has the possibility that in certain areas within the lumber dryer the wood moisture can be increased if necessary, for example by spraying or steaming. The conditioning device 4 ensures that the screeds leaving the conditioning device have a very uniform initial moisture, whereby particularly good and precise cutting results are achieved. The wood moisture content of the screeds 2 leaving the conditioning device 4 is approximately 50%.

After the wooden planks have been conditioned, they are separated and fed to the cutting device, designated overall by reference number 6, in which the aligned wooden planks are guided past one or more cutting stations 8 arranged one behind the other. Each time the screed is moved past a cutting station, a wooden lamella 10 is cut off, the screeds 2 being circulated within the cutting device 6 (indicated by the dashed line 12) until the screed is completely cut into the individual wooden lamellae. The cutting device 6 as such is essentially known in the art and therefore requires no further explanation.

From the cutting device 6, the wooden lamella 10 cut from the planks 2 are automatically transported to a conveyor 14, on which they are arranged parallel to one another and are conveyed through a drying device 16. At the output of the cutting device 6, a marking device 18 is arranged, which marks the upward-facing side of the wooden slats 10 leaving the cutting device 6. This upward-facing side is the closed side of the board lamella, which is suitable for later use as a visible surface.

The uniformly dimensioned, marked, arranged side by side wooden slats 10 then continuously run through the drying device 16, which is designed as a drying tunnel. This drying tunnel is equipped with a temperature control, which enables exact temperature control within the dryer. The wood slats 10 leaving the drying device 16 are dried very evenly on wood moisture up to about 6%.

In the case of the exemplary embodiment according to FIG. 1, the throughput speed of the wooden slats 10 through the drying tunnel is 2.5 m per minute, the drying temperature being approximately 165 ° C. in the case of spruce slats with a thickness of 8 mm. The dryer volume is approximately 1000 m³ and the amount of exhaust air is approximately 15000 m³ per hour. The drying tunnel is divided into several, for example three, temperature zones, as seen in the conveying direction of the wooden slats. The wooden slats to be dried can be arranged one above the other within the drying tunnel 16 on one or more floors.

The wood fins 10 leaving the drying device 16 then pass through a cooling or air-conditioning device 20 in which the cooling of the wood fins is accelerated in order to have the optimum material temperature available for further processing in the post-processing device 24.

Furthermore, a moisture measuring station 22 is provided behind the cooling device 20, in which the drying data of the wooden lamellae 10 are measured in order to be able to monitor and control the proper operation of the drying device 16. For this purpose, the data measured in the moisture measuring station 22 are fed to a data acquisition and storage device 23, from which the data can be printed out on request or can be used for temperature control of the drying device 16.

From the drying device 16 or the moisture measuring station 22, the dried wooden lamellae 10, the twisting of which has been reversed by the heat treatment in the drying device 16 and which are thus completely flat, are fed to the post-processing device 24 by means of suitable conveying means. In the case of the exemplary embodiment described, this post-processing device 24 comprises a maximum of four-sided high-speed grinding machines which enable the dried lamellae to be continuously processed at feed speeds of up to 150 m per minute. The individual units of the high-speed grinding machines known per se can be switched on individually, so that only those sides of the wooden slats are always processed for which such post-processing is necessary, taking into account the later intended use. In the post-processing device 24, the wooden slats are machined to the tightest tolerances in the order of magnitude of a total of 1/10 mm. As already mentioned above, high-speed milling units can be used, for example, for the edge processing of the wooden slats, which work in conjunction with high-speed grinding machines for processing the upper and lower surfaces of the wooden slats.

After the wood slats have been processed in the post-processing device 24, the wood slats, which may be marked again in the further marking station 18 'connected downstream of the post-processing device 24, are fed to a sorting device, designated overall by reference number 26, in which the wood slats are classified according to their quality and corresponding different transport routes. The structure of the sorting device 26 can also be seen from FIG. 2.

The wood lamellas 10 coming from the post-processing device 24 are first continuously fed to a sorting line 28, in which they are classified in terms of their quality, for example according to three quality classes A, B and C. This classification can be done automatically or by appropriately trained personnel. The individual wooden slats 10 are shifted in depth according to the quality class assigned to them, it being possible, for example, to proceed in such a way that the wooden slats of quality class A, i.e. H. of the highest quality class, are not moved, the wooden slats of quality classes B and C are moved backwards, the wooden slats of quality class C being moved lower than those of quality class B. At the end of the sorting line 28, light barrier devices 30 are provided, which correspond to the respective positions Scan the wooden slats 10 passing underneath them and thereby record the classification of the respective wooden slats 10 and, if necessary, register them.

Subsequently to the sorting line 28, the wooden lamellas 10 are transferred to a revolving elevator 32, which feeds the individual wooden lamellas 10 to different sorting sections 34, 36, 38 according to their respective quality class. The sorting lines 34, 36, 38 are each corresponding Assigned flaps 40, which are controlled via a control device 42 connected to the light barrier device 30. The control device 42 has the effect that, depending on the determined quality class of the individual wooden lamellas 10, the flaps 40 of the respective sorting section assigned to the respective quality class are activated with a corresponding delay.

Furthermore, a further processing line 44 is provided below the further processing lines 34 to 38, which can optionally also be controlled, so that the wooden slats deposited thereon can be fed directly to a further processing machine, for example a continuously operating side gluing press or the like. In contrast, the further processing lines 34 to 38 are fed to the further processing lines Wooden slats stacked in the stacking stations 36, a counting device (not shown in more detail) being present, which counts the wooden slats deposited on the stack and triggers the forwarding of a complete stack to a further elevator 48, which feeds the wooden slat stacks 50 to a conveyor device 52, which feeds the individual stacks transported to the final stacking locations 54, where the wooden slats are stacked according to their grade. The pre-sorted and stacked wooden slats are then transported to further processing lines, such as a fully automatic press line, with the help of suitable transport equipment.

3 shows an alternative embodiment of a device according to the invention in the area of the cutting device and the unit connected upstream thereof. In the case of this exemplary embodiment, a measuring station 60 is arranged in front of the cutting device 6 in the transport path of the planks to be fed to this cutting device, which measuring station 60 detects the moisture the timber plank measures and generates a corresponding electrical output signal. This electrical output signal is fed to a control device 62 which controls one or more cutting parameters of the cutting device 6 as a function of the measured moisture; Suitable pressure parameters are in particular the contact pressure of the planks to be cut against the cutting knife or the cutting thickness. In this way, tolerances resulting from different wood moisture levels can be eliminated, whereby the desired cut optimization can be achieved without the occurrence of residual lamellae.

In the exemplary embodiment described above, the method steps are carried out continuously. Alternatively, however, they could also be carried out with suitable intermediate storage between certain process steps with subsequent loading.

The above-mentioned conditioning device upstream of the cutting device 6 can, according to a preferred exemplary embodiment of the invention, be designed in such a way that the sawn timber is first pre-dried in a drying chamber to a predetermined wood moisture content, depending on the wood thickness, for about one to two days. From there, the sawn timber is then brought into a steaming chamber by means of a forklift, and here the wood surface is specially steamed up. The sawn timber packages are then individually conveyed to a tilting table, where the sawn timber is unstacked in layers. The tilting table is located in a climate chamber in which the wood temperature is kept at around 70 to 80 ° Celsius. From here, the separated sawn timber is passed through a hot water bath and then it is fed to the cutting station 8.

4 shows an exemplary embodiment of a system for carrying out the aforementioned method steps (damping, separation in the climatic chamber, water bath). The steaming chamber is designated by the reference number 64, the air conditioning chamber by the reference number 66, the tilting table by the reference number 68 and the water bath by the reference number 70.

In the steaming chamber 64, the wood dried in the drying chamber (not shown) is heated by means of steam and in particular the drying that takes place in the outer regions of the raw wood is raised to the average moisture content of the entire wood. Steaming also has the task of uniformly heating the raw wood and achieving uniform wood temperatures in the entire raw wood stack. The residence time within the steaming chamber can be approximately 30 to 200 minutes, depending on the requirements.

In the air conditioning chamber 66 downstream of the steaming chamber 64, the previously reached uniform humidity and the heat in the individual woods are maintained and the air conditioning chamber simultaneously forms a buffer zone in which the planks of the plank stack 82 are separated and fed to the water bath 70.

The woods that are now separated and lying next to one another are transported through a tempered water bath 70 via suitable conveying devices. This water bath has the task of making the individual boards in their structure shortly before they are cut open again in the cutting station 8, in order to thereby substantially reduce the risk of tears or other damage to the wood on the wood slats 10. Furthermore, it has been shown that the wood pretreated in this way results in wood lamellae, which emerge from the Cutting station 8 are significantly less twisted.

The individual woods have a residence time in the water bath 70 of about 2 to 5 minutes. The water bath has a temperature of up to 95 ° Celsius, as a result of which a temperature at the kerf up to 70 ° Celsius can be reached at the cutting devices of the subsequent cutting station 8.

The pretreatment of the planks described in connection with FIG. 4 has a number of advantages. First of all, there is a much better cut quality, especially in the area of branches. Furthermore, there is a much gentler wood treatment during cutting in the cutting device. Ultimately, there are optimal cutting results and very good parallelism of the slats, especially when the raw material is too dry and not optimal.

The above-mentioned pretreatment considerably reduces the unevenness in the cut on the lamella surfaces, so that the cut and then dried lamellae are largely flat and no longer have to be worked on, or only slightly.

In a further exemplary embodiment of the invention, the cutting bolt can be preconditioned in whole or in part by irradiation by means of microwaves. In this way, a uniform moisture and temperature distribution in the sawn timber to be cut can be achieved in a comparatively simple and effective manner.

Reference list

2nd

Planks

4th

Conditioning device

6

Cutting device

8th

Cutting station

10th

Wooden slat

12th

Circulation

14

Sponsor

16

Drying facility

18th

Marking device

20th

Cooling device

22

Moisture measuring station

23

Data acquisition and storage facility

24th

Post-processing facility

26

Sorting device

28

Sorting line

30th

Light barrier device

32

Elevator

34

Sorting line

36

Sorting line

38

Sorting line

40

Valves

42

Control device

44

Processing line

46

Stacking stations

48

Elevator

50

Stack of wooden slats

52

Conveyor

54

Stacking places

60

Measuring device

62

Control device

64

Steam chamber

66

Air conditioning chamber

68

Tilting table

70

water bath

82

Pile of planks

Claims (34)

1. A method for the production of wood sheets from cut wood, characterised by the combination of the following method steps:

   A) Sawdust-free cutting of the cut wood (2) into the individual wood sheets (10),

   B) controlled drying of the wood sheets (10), and

   C) subsequent machine working of one or more sides of the dried wood sheets (10) in particular by grinding,

   wherein before method step A) the cut wood (2) is preconditioned with regard to humidity to achieve a uniform initial humidity.
2. A method according to claim 1, characterized in that the method steps A) to C) are carried out continuously.
3. A method according to claim 1, characterized in that before method step A) the cut wood (2) is pre-dried to achieve a uniform initial humidity.
4. A method according to claim 3, characterized in that the cut wood (2) is preconditioned to 40 to 60%, preferably to approximately 50% humidity.
5. A method according to claim 1, characterized in that before the method step A), the humidity of the cut wood (2) is measured and in step A) the cutting parameters are controlled according to the measured humidity.
6. A method according to claim 5, characterized in that the contact pressure in the region of the cutting blade and/or the cutting thickness are controlled as cutting parameters.
7. A method according to one of the preceding claims, characterized in that the individual cut wood planks (2), which are to be cut up into wood sheets (10) are carried in a circuit in a manner known per se past cutting blades until the cut wood planks (2) are completely divided up into the individual wood sheets (10).
8. A method according to one of the preceding claims, characterized in that the thickness of the cut wood (2) is adapted to the thickness of the wood sheets (10) which are to be produced, such that in method step A) no residual sheet arises which is of a different, in particular smaller, thickness than the nominal thickness of the wood sheets (10).
9. A method according to one of the preceding claims, characterized in that the cut wood sheets (10) in method step B) are dried to a wood humidity of approximately 4 to 8%.
10. A method according to one of the preceding claims, characterized in that following the method step A) and, if required, additionally also following the method step B), the wood sheets (10) are marked with respect to their underside facing the cutting blade of the cutting apparatus and/or their upper side facing away from the cutting blade.
11. A method according to one of the preceding claims, characterized in that the wood sheets (10) are cooled following the method step B).
12. A method according to one of the preceding claims, characterized in that the wood sheets (10) are monitored with regard to their humidity between the method steps B) and C) and are marked if required, whereby the measurement data are picked up and are stored so as to be able to be recalled.
13. A method according to one of the preceding claims, characterized in that the wood sheets (10) following method step C) are carried continuously over a sorting line (28), are classified with regard to their qualities and are subsequently sorted accordingly.
14. A method according to claim 13, characterized in that the sorted wood sheets (10) are stacked.
15. A method according to claim 13 or 14, characterized in that the sorted wood sheets (10) are passed to the further processing stations such as side glueing press, assembly machine or the like.
16. A method for the production of products made up in several layers from wood sheets (10), such as glue binders, glued laminated wood, three-ply boards and the like, according to one of the preceding claims, in which cut wood (2) is cut in a sawdust-free manner into wood sheets (10), characterized in that the visible side(s) of the product are formed exclusively by the closed sides of the wood sheets facing away from the cutting blade in the cutting process of the wood sheets.
17. A device for the production of wood sheets (10) from cut wood (2), with a cutting apparatus (6) for sawdust-free cutting of the cut wood into the individual wood sheets,
    characterized in that
    before the cutting apparatus (16) a humidity-conditioning apparatus (4) for the cut wood (2) is arranged,
    following the cutting apparatus (6) a drying apparatus (16) is arranged, to which the wood sheets produced in the cutting apparatus are continuously passed from the apparatus automatically, whereby the wood sheets run continuously through the drying apparatus, and that following the drying apparatus (16) a subsequent machining working apparatus (24) is arranged, to which the wood sheets dried in the drying apparatus (16) are continuously fed from the drying apparatus, whereby the wood sheets run continuously through the subsequent working apparatus.
18. A device according to claim 17, characterized in that before the cutting apparatus a humidity-measuring apparatus (60) for the cut wood (2) is arranged, the output signal of which is able to be fed to a control apparatus (62) to control one or more cutting parameters of the cutting apparatus (6), such as in particular contact pressure in the region of the cutting blades and/or cutting thickness.
19. A device according to claim 17 or 18, characterized in that the drying apparatus (16) is a temperature-controlled drying oven.
20. A device according to one of claims 17 to 19, characterized in that between the cutting apparatus (6) and the drying apparatus (16) and also, if applicable, additionally following the subsequent working apparatus (24), a marking apparatus (18) is arranged for the preferably visual marking in each case of a particular side of each wood sheet (10).
21. A device according to one of claims 17 to 20, characterized in that following the drying apparatus (16) a cooling apparatus (20) is arranged, in particular in the form of a fan.
22. A device according to one of claims 17 to 21, characterized in that following the drying apparatus (16) - if applicable, behind the cooling apparatus (20) - a humidity measuring apparatus (22) for the wood sheets is arranged, which communicates, if required, with a data pick-up and memory apparatus (23).
23. A device according to one of claims 17 to 22, characterized in that the subsequent working apparatus (24) comprises individually connectable components for the selective subsequent working of the side faces or respectively edges of the wood sheets (10) running parallel to the direction of advance.
24. A device according to claim 23, characterized in that the components comprise high speed grinding machines.
25. A device according to claim 23 or 24, characterized in that the components comprise high speed milling machines, in particular for working the edges of the wood sheets.
26. A device according to one of claims 17 to 25, characterized by a sorting apparatus (26), arranged following the subsequent working apparatus (24), to which sorting apparatus the subsequently-worked wood sheets (10) are fed continuously and which the wood sheets run through continuously, whereby the sorting apparatus comprises a sorting line (28) for the classification of the wood sheets according to particular quality criteria (A,B,C), an optical recognition apparatus (30) to recognize the different classifications, a distributor apparatus (32, 40) to distribute the wood sheets to different transport paths (34, 36, 38, 40) according to the different quality criteria, and also a control apparatus (42) to control the distributor apparatus as a function of the output signals of the recognition apparatus (30).
27. A device according to claim 26, characterized in that the classification takes place by different changes in position of the wood sheets (10) on the sorting line (28) and that the optical recognition apparatus is a light barrier apparatus (30) indicating the different positions.
28. A device according to claim 26 or 27, characterized in that an elevator (32) is arranged after the sorting line (28), which elevator feeds the wood sheets (10) according to their classification (A,B,C) to further transport paths (34, 36, 38, 44) via deflectors or flaps (40) controlled by the control apparatus (42).
29. A method according to one of claims 1 to 16, characterized in that the cut wood (2) is predried and then steamed.
30. A method according to claim 29, characterized in that the cut wood (2) is conveyed to a water bath (70), which is preferably heated, after having been steamed.
31. A method according to claim 1, characterized in that the cut wood (2) is conveyed to a heated water bath (70) and, immediately after that, is conveyed further to be cut.
32. A method according to claims 29 and 30, characterized in that the cut wood (2) is conveyed through an air-conditioning zone (66) arranged between the steaming zone and the water bath (70).
33. A method according to one of claims 1 to 16 and 29 to 32, characterized in that pre-conditioning comprises the step of treating the cut wood (2) by means of microwaves.
34. A device according to claim 17, characterized in that it comprises a steaming chamber (64), a water bath (70) and, if necessary, an air-conditioning chamber (66) arranged between said steaming chamber and said water bath (70).

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