EP0107690A1

EP0107690A1 - Method and device for transforming billets into construction wood.

Info

Publication number: EP0107690A1
Application number: EP83901367A
Authority: EP
Inventors: Peter Polaczek
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-05-04
Filing date: 1983-05-04
Publication date: 1984-05-09
Anticipated expiration: 2003-05-04
Also published as: DE3216669A1; EP0107690B1; DE3381994D1; WO1983003791A1

Abstract

Dans le procédé pour transformer des billes de bois en bois de construction avec cercles annuels de croissance verticaux ou en bois pour le contreplacage, la bille est d'abord coupée en tronçons de longueur aisée à manier, puis fraisée circulairement, ensuite le tronc est divisé en secteurs en forme de coin qui sont collés ensemble. Au moins deux secteurs (4, 4a) en forme de coin découpés dans la section du tronc sont placés l'un sur l'autre, une face (7, 8) de chaque coin étant munie d'une couche de colle, de telle manière que les autres faces (5, 6) des coins soient parallèles et que les cercles de croissance (3) soient debout. Les secteurs (4, 4a) sont ensuite collés avec application d'une pression. A cet effet, on utilise un dispositif présentant deux surfaces de butée (13, 14) disposées parallèlement entre elles à une distance Y sur lesquelles les surfaces (5, 6) de secteurs d'un bloc de secteurs (17, 27) peuvent s'appuyer. Les secteurs (4, 4a) sont parallèles aux surfaces de butée (13, 14) et peuvent être soumis à la pression à l'aide de moyens de transmission de pression.In the process of transforming wooden logs into timber with annual vertical growth circles or into wood for plywood, the log is first cut into sections of length easy to handle, then circularly milled, then the trunk is divided into wedge-shaped sectors that are glued together. At least two wedge-shaped sectors (4, 4a) cut out from the trunk section are placed one on the other, one face (7, 8) of each corner being provided with a layer of glue, such so that the other faces (5, 6) of the corners are parallel and the growth circles (3) are upright. The sectors (4, 4a) are then bonded with the application of pressure. For this purpose, a device is used having two abutment surfaces (13, 14) arranged parallel to one another at a distance Y over which the surfaces (5, 6) of sectors of a block of sectors (17, 27) can be 'to press. The sectors (4, 4a) are parallel to the abutment surfaces (13, 14) and can be subjected to the pressure using pressure transmission means.

Description

_V he _saw ren for processing of logs to Konstruktionsho with _eh forming st annual rings and apparatus for Accomplishment of the process.

The invention relates to a method for processing round wood into construction wood with standing annual rings, in which the round wood is first cut to length and the trunk is divided into wedge-shaped sector pieces which are mutually glued to one another and a device for carrying out the method.

In the production of sawn timber from logs, mainly the core area is used for the production of sawn timber, while the partially round-limited side timbers are cut for further processing into chipboard. The possibilities for the direct use of the side timbers are small because of the difficulties caused by the round cross-sectional limitation and only of a subordinate nature. It is known to profile the side timbers at the edges in such a way that they are used as planks or the like. Can find use. However, it has been shown that such processing of the side timbers is too difficult. Neither the round boundary surface nor the acute-angled and therefore imprecise side edges allow reliable guidance in planing or milling machines. For this reason, e.g. Bar planks for panel cladding mainly made from the valuable sawn wood of the core area of the trunks. The use of the timber cross-section is therefore more impaired due to the poor usability of the side timbers, the smaller the log diameter.

A particular problem in wood processing is the working of the wood, ie its change in shape due to swelling and shrinking when moisture is absorbed or released. Comes to this disadvantageous property the antisotropy of wood, which causes wood to swell or shrink to different extents in the three different anatomical directions - longitudinal, tangential, radial. The swelling or shrinkage is tangentially about twice as large as radial, the

Change in length in the axial - and thus longitudinal - direction can be neglected. This means that the stamina so important for construction timbers is directly dependent on the position of the annual rings in the wood cross-section. In the conventional way of cutting wood, boards, squared timbers or beams with always different annual ring positions are produced, the yield of timber being relatively poor. The manufacture of boards and wooden parts with standing annual rings has so far regularly led to a poorer degree of utilization or has required compromises with regard to the position of the annual rings. In order to avoid these disadvantages, a method has already been proposed in which the round-milled round wood is divided into wedge-shaped sectors, which are then dried. After drying, the wedge tip and rind are removed from the sectors and the sectors prepared in this way are then mutually placed with their wedge surfaces and glued together. This creates an endless plate in which the

Annual rings have largely the same direction. By means of separating cuts arranged perpendicular to the sectors, structural timber with standing annual rings is then formed from the continuous panels. The disadvantage of this known method is that sectors of a round timber cannot be used for the production of construction timbers of different thicknesses. Furthermore, as with all other processes, only a dome production is possible according to this process, ie in addition to the desired main product such as. B. construction wood, by-products such as rinds and side boards. Should follow this procedure if possible It is necessary to divide the log cross-section into sectors with small wedge angles, but this would lead to narrow, unusable rinds. The same effect occurs with this known method when machining small log diameters. The work processes in these known processes are controlled by the desired end product, which makes an individual and therefore complex and expensive production necessary.

The object of the invention is to demonstrate a method in which board-like structural timber with only standing annual rings can be produced from logs, which does not require any dome production compared to known methods and thus ensures a high timber yield with uniform quality at any log diameter, whereby from the Diversity of the intermediate products that can be produced by the process and that can be selected in each case for the further processing. Another object of the invention is to show an apparatus for carrying out the method.

»

According to the invention, the object is achieved in that at least two of the branches are made from a circular one

Trunk cross-section of the wedge-shaped sectors, each with a sector area provided with a layer of glue, are placed on top of one another in such a way that the respective other sector areas are arranged parallel to one another and the annual rings are upright and then the

Sectors are glued together with a pressure to form a sector block.

According to a further embodiment of the invention, the device for carrying out the method consists of a sawing device, a drying device which can be loaded with sectors with a drying basket and a pressing device. Further features of the invention are described in the subclaims and explained in more detail below with reference to the drawings.

It shows

1 is a schematic representation of the construction of a construction part according to the invention from sectors of a log in a side view in section,

2 shows a longitudinal connection of two structural members in a schematic side view in section,

3 possible embodiments of cross connections and 3 of construction timber in a schematic cross view in section,

4a a construction part required for veneer production and 4b in cross-section in section,

5a shows the veneer image in the case of separating cuts carried out on a structural part in and 5b in different directions,

6a embodiments of an inventive and 6b sawing and drying device in table views,

Fig. 7a, the pressing device for producing sector blocks and 7b in a schematic cross section.

As shown in Fig. 1, the

Rundholz 1 by mirror cuts wedge-shaped sectors

4,4a. At least two wedge-shaped sectors placed that the sector surfaces 7,8 touch and the outer sector surfaces 5,6 are arranged parallel to each other. A glue layer is provided between the sector surfaces 7, 8, which serves to connect the sectors 4, 4, 5 to a sector block 117.

If extended construction timbers are desired, it is possible to construct construction timbers 9 formed from the sectors 4, 4a on the end faces 18, 19 with one another

10 to connect. For example, the

End faces 18, 19 may be formed in a manner known per se (FIG. 2), the surfaces of which are coated with a layer of glue. By compressing the structural parts 9 in a longitudinal direction

15 direction is then their dimensionally stable connection. With a connection by means of finger joints 10, however, a slight loss of material must be accepted.

20 It is also possible to produce 17 construction parts of greater width from sector blocks. For this purpose, it is only necessary to form on the longitudinal sides 20, 21 of the segment to be joined blocks 17, for example, also Keilverzinkungen 10, the gearing surfaces to press ^• 2.5 with glue to be coated and then the individual Sektor¬ blocks by lateral pressure on each other. It is also possible to remove the round end section 22 of each sector block 17 by means of a separating cut and then to remove the sector blocks 17 from theirs

30 butt-glued smooth milled edge surfaces 23 to one another (FIG. 3a). By milling the round end section 22, an oblique edge surface 23 is achieved, but is no longer perceptible after the gluing. Another possibility is shown in FIG. 3b

35 shows the connection of two sector blocks 17. Finger tines 24 are formed on the round end sections 22 of the sector blocks 17 to be connected to one another in such a way that the finger tines 24 of the one Sektoj? -. ^"~ block 17 can be inserted into the grooves 25 between the finger tines 24 of the other sector block 17. The finger tines 24 can be held in the grooves 25 both by clamping action and by gluing. 5 This toothing shown in Fig. 3b has the

Advantage that no material loss occurs in the area of the round end sections 22. In addition, the effective glue surface is increased and guidance is achieved by the finger tines '24 and grooves 25. For special ones

10 use cases such as for floor boards or shuttering boards, sector blocks 17 provided with finger tines 24 and grooves 25 can therefore also be joined together without glue, such as tongue and groove boards. If several sectors and sector blocks 17 form a large sector block

15 27 to be joined together, devices 12d, 12e can be used (FIGS. 7a and 7b). Both devices have a stop 28, which is arranged on the lateral end section 26 of the stop surfaces 13, 14 and on which the side stop facing it

20 end sections 26 can be brought into contact. In the

In the region of the other lateral end section 30, device 12d acts on stamps 16 on the sectors 4, 4a and sector blocks 17 -25 arranged between the stop surfaces 13, 14

It is also possible to use, for example, elastic pressure-resistant hoses 32 instead of the pressure stamp 16 (FIG. 7b). In this case, a stop 31 is formed on the lateral end section 30

30 which the elastic pressure-resistant hoses 32 can be fixed in their position. In the device 12e, elastic pressure-resistant hoses 32 are arranged alternately between the round end sections 22 of the sectors 4, 4a and the stops 28, 31. The holding means

35 for fixing the position of the elastic pressure-resistant hoses 32 are not shown in detail. The formation of veneer strips expediently takes place in such a way that a sector block 27 is first produced, then vti-.r " A separating cut is carried out parallel to the sector area 6 below the sector area 5 in the direction X. It is also possible to make this separating cut in the direction X '(FIGS. 4a and 4b).

In the case of a separating cut in the direction X, the veneer has a stripe pattern, as is shown schematically in FIG. 5a. With a separating cut in the direction X ', a flat image is achieved for the veneer. For veneer production, it is necessary that the sector blocks 27 have to be moist before the separating cuts. In contrast to the production of construction timber, it is expedient and, in the case of certain woods, also necessary for the sectors 4, 4a to be glued with moisture. Since it is only in the manufacture of veneers

Veneer image arrives and not on the stamina, the annual rings 3 need not be very straight. Furthermore, it is possible to use sectors 4, 4a with a larger wedge angle than is the case for the production of construction timber. The sectors 4, 4a of a trunk are expediently glued to form a large sector block 27, since this avoids frequent clamping in the veneer knife machine and better material utilization is achieved.

In order to be able to make optimum use of the trunk cross-section of the round timber 1, it is expedient to use two sectors 4, 4a with a wedge angle of 22.5 ° and seven segments with a wedge angle of 45 ° for a large sector block 27.

By using the method described, it is possible to achieve a uniform and high-quality product with very high material utilization. A dome production is not necessary. Rather, tree trunks of different diameters can be processed. In addition, different wedge angles of the sectors 4, 4a are possible, so that the quality gr is controllable. When the method according to the invention is carried out, the best possible material utilization results compared to known methods. Sorting boards during further processing, for example on the right or left side, is not necessary, since such boards no longer occur due to the arrangement of the annual rings 3. Conditions previously taken into account when carrying out wooden constructions, such as warping, changes in angle, uneven addition of shrinkage and the like. The like. need not be observed. This simplifies the calculation and standardization of construction parts 9. These can be used wherever so-called rift boards have previously been required. In addition, an application is possible where previously boards with changing annual ring course and all the disadvantages associated therewith had to be used, since these were predominantly incurred during the incision. The sector blocks 17 can also be used for the production of the middle layers for plywood panels, the quality of which then

Correspond to the stamina of the so-called stick middle layers with standing annual rings.

Considerable advantages also arise in the case of artificial wood drying in particular. When drying normally cut wood, shrinkage cracks first appear in the radial direction. In order to avoid this, it has previously been necessary to carry out the drying processes carefully and very slowly, which results in high time and energy requirements. As a result of the type of incisions, the radial drying cracks are anticipated when the method according to the invention is carried out. The wedge-shaped sectors 4, 4a shrink like any other wood, but do not warp in the process. Post-processing such as leveling by planing after drying and the associated Loss of material is thus largely avoided. Due to the much lower risk of cracks, drying can also be done faster and cheaper.

It is particularly advantageous to use sectors 4, 4a or

Produce sector blocks 27 by means of a device which consists of a saw assembly 33 _"a can be charged with a drying basket 41 Trockeinrichtung 34 and a pressing device 35th The sawing device 33 and the drying device 34 are shown schematically in FIGS. 6a and 6b. The log 1 to be processed is first sawn into handy lengths and then milled into a circular cylinder. This cylindrical log 1 is then introduced into the sawing device 33. This consists of sawing units 36 arranged one behind the other in the feed direction Z of the roundwood 1, which can be pivoted about an axis of rotation coaxial to the central axis 37 of the roundwood 1 located in the sawing device 33. By appropriate adjustment of the sawing units 36, it is possible for them to make longitudinal cuts in the round timber 1, which are adjusted according to the center angle of the desired sectors 4, 4a. By means of this sawing device 33, it is thus possible to achieve a desirable high level of quality, ie to cut out a maximum number of sectors 4, 4a per log 1. As a result, the annual rings 3 are all the more straight in the glued end product, as a result of which the corresponding properties such as stamina, resistance to warping, etc. are particularly good. The saw units 36 are designed so that they can be moved out laterally when not in use, for maintenance, for adjusting or for changing the saw blade. The sawing units 3 can expediently be designed as band saws. For the advancement of the round timber 1 through the sawing device 33, a conveying device 38 is provided, which has circularly arranged adjustable conveying rollers 39. The conveyor rollers 39 can the respective diameter of the log 1 to be cut can be adapted so that the log 1 is always arranged centrally in the sawing device 33. A drying device 3 is arranged at the exit of the sawing device 33. The sectors 4, 4a produced in the sawing device 33 are first inserted into a drying basket 41 at the exit of the sawing device 33. In the drying basket 41, the sectors 4, 4a are arranged in a circular cross-section and are held between radially extending holding webs 45. By means of a pressing device 3 the z. B. may consist of compression springs 46, the sectors 4, 4a are pressed into the drying basket 1 until they lie flat against the retaining webs 45.

The drying basket 41, which can also be designed as a drying drum, is pushed into the drying device 3 with the wedge-shaped sectors 4, 4a and can be rotated therein. Nozzles 47 are formed in the wall 44 of the hollow chamber 42 of the drying device 34, through which drying air is blown into the hollow chamber 42. Exhaust air openings (not shown in more detail) are provided diametrically to the nozzles 47, so that full-area transverse ventilation in the drying device 34 is achieved. It is possible to use suitable air guiding means to design the air flow in such a way that either the entire lateral surface or only part of it is acted upon. By appropriate design of the nozzles 47, it is possible that when the

Drying basket 41 in each case only the space between two sectors 4, 4a is intensively flowed through with the drying air. For this reason, the holding webs 45 are formed such that a free space through which drying air can flow is formed between the sectors 4, 4a. The drying device 3 is for all conventional drying processes that work with air movement such as B. warm air, hot air, hot steam, condensation drying u. Like applicable.

5 By using the drying basket 41, otherwise usual stacking work for the goods to be dried is avoided. With regard to the wedge-shaped design of the sectors 4, 4a, an extremely favorable use of space is achieved by the star-shaped arrangement. If the

10 drying basket 41 is filled with the sectors of a round timber 1, there are advantages for the further processing stages, since z. B. sorting of individual sectors 4, 4a is no longer required. In addition, the training of the drying

15 direction 3 prevents a different air speed over the material to be dried, which provides additional protection against warping.

In addition to the 20 pressing device 35 already shown in FIGS. 7a and 7b, such a pressing device can also be used in which the stop 28 is arranged horizontally and the stop surfaces 13, 14 are horizontally displaceable relative to one another. With such a configuration of the pressing device 35, the segments and tips of the sectors 4, 4a, which face away from the '2-5 stop 28, of the sectors 4, 4a mounted between the stop surfaces 13, 14 can be pressurized by means of a pressure plate or pressure rail which extends over the entire sector block 27 will. This design of a 30 press device 35 is extremely advantageous in handling. To produce a sector block 27, the first four sectors 4 are first placed on the stop 28 so that their wide edges touch and the lower right edge of the right sector 35 4 touches approximately the stop surface 14. Since the focus of the sectors 4, 4a is relatively far below, the sectors 4, 4a remain with their peaks pointing upwards. Then the left stop surface 13 becomes careful moved up until it approximately touches the lower edge of the left sector 4, 4a. Now the remaining sectors 4, 4a or the outer halves of sectors can be placed between them from above. To ensure that all sector surfaces touch during pressing, the movable left stop surface 13 or right stop surface 14 is now somewhat withdrawn, so that the sectors 4, 4a lying above can be pressed down a small way until their tips are in each case protrude slightly between the wide edges of the adjacent sectors 4, 4a. Then the upper pressure plate is fixed and the sector block 27 is pressed under pressure by means of the stop surface 13 or both stop surfaces 13, 1.

The method according to the invention and the device described are suitable for various fields of woodworking. The use in the production of plywood is advantageous since a high wood yield is achieved in connection with an excellent technological quality of the finished panels. Use in the manufacture of veneers is also advantageous, since round timber 1 of small dimensions can also be used according to the method described. This has the advantage that rotten kernels occur relatively rarely and the wood yield is very good. In finished plywood panels, the veneers have standing annual rings. As a result, the swelling / shrinkage potential in the board plane is only about half as large as in the known plywood boards. Due to the uniform structure, the internal tensions are so low that the plates also have very good stamina.

Claims

PATENT CLAIMS

1. Process for processing logs into construction timber with standing annual rings, in which the logs are first cut into lengths and the trunk is divided into wedge-shaped sector pieces which are mutually glued to one another, characterized in that at least two of the logs are milled from a circular cross-section separated wedge-shaped sectors, each with a sector surface provided with a glue layer, arranged parallel to one another and the annual rings arranged upright, and then the sectors are glued to one another with application of a pressing pressure to form a sector block.

2. The method according to claim 1, characterized in that the log is first sawn into handy lengths and then milled into a circular cylinder, then the cylinder is separated into sectors with the same central angle, which are then dried, smoothed on the radial surfaces, then glued on one side and in pairs so that the outer sector surfaces are parallel to each other, and then the sectors are joined together under pressure.

3. The method according to claim 1 and 2, characterized in that to increase the length and / or width of the

Construction wood, the sector blocks consisting of wedge-shaped glued sectors are connected to one another at the end faces and / or the long sides by means of a spline or the like known per se and / or by gluing.

4. The method according to claim 1 to 3, characterized gekennzeich¬ net that in order to produce an endlessly long board-like construction wood in a repetitive manner two sectors with parallel to each other on e- ordered outer sector surfaces collapsed, pressed together at their ends and secured against displacement and then milled at the front edges of the sectors finger joints or the like, then the finger joints are coated with glue 5 and then the sectors are unfolded and coated on their radial surfaces with glue and then the sectors are offset in length again with mutually parallel outer sector surfaces and are pressed together and then the next two sectors are joined by gluing at the 10 end edges.

5. The method according to claim 1 and 2, characterized gekennzeich¬ net that for the production of construction wood with

15 standing annual rings and small thickness of the circular cylinder halved on the long side and then boiled or subjected to vapors, then the cylinder rotatably clamped about its central axis and wedge-shaped veneers from the flat surface of the cylinder

20 are cut off with a knife, dried and glued to each other with mutually parallel outer surfaces.

6. The method according to claim 1 and 2, characterized in -25 net that for the production of veneers with flat or

Streak grain the sectors separated from a cylindrical log and a sector halved by longitudinal section are kept moist by steam or hot water and then the radial surfaces are smoothed,

30 then provide the sectors in the area of the smoothly machined surfaces with glue and mutually combine them so that the two halves of the halved sector each achieve a generally rectangular cross section of the sector block

35 form its outer end, then the sectors pressed into a fixed sector block and then through radial or tangential cuts aligned parallel to the annual rings of the sectors are cut out of the sector block veneer strips.

5 7. The method according to claim 6, characterized in that the sectors intended for veneer production are glued wet to a sector block.

8. The method according to claim 6 and 7, characterized gekennzeich- 10 that moist warm to moist hot sector blocks are used for veneer production.

9. The method according to claim 3, characterized in that at the round end portions of each other

15 connecting sector blocks finger tines or the like. are designed such that the finger tines of one sector block can be inserted into the grooves between the finger tines of the other sector block.

20 10. The method according to claim 9, characterized in that the finger prongs are held by clamping action in the grooves.

11. The method according to claim 9, characterized in that 25 the finger prongs are glued in the grooves.

12. The method according to claim 3, characterized in that profiles are formed in the outer surfaces of the round segments of the sectors so that two radially 0 successive sectors in the area of their segments inserted into each other and gfls. can be glued.

13. The method according to claim 1 to 13, characterized gekennzeich¬ net that the surfaces to be glued to the sectors 5 in the area of penetration of the glue in wet sectors by contact heat, infrared radiators or the like. dried briefly, then provided with a moisture-resistant glue and pressed together at elevated temperature.

14. Device for carrying out the method

Claims 1 to 13, characterized by a sawing device (33), a drying device (34) which can be loaded with a drying basket (41) and a pressing device (35).

15. The apparatus according to claim 14, characterized in that in the sawing device (33) in the feed direction of the round timber (1) one behind the other sawing units (36) are arranged around a central axis (37) of the round timber (37) in the sawing device (33) 1) the coaxial axis of rotation can be rotated so that each saw unit (36) can be adjusted according to the central angle of the sector (4, 4a).

16. The apparatus according to claim 15, characterized in that the round timber (1) by the sawing device (33) by means of a conveyor (38) with circular arranged adjustable feed rollers (39) is movable.

17. The apparatus according to claim 14, characterized in that the drying device (34) consists of a hollow chamber (42) into which the drying basket (41) loaded with the sectors (4, 4a) at the output of the sawing device (36) can be inserted and can be supplied with drying air through cross ventilation.

18. The apparatus according to claim 17, characterized in that the sectors (4, 4a) in the drying basket (41) are arranged in a circular cross section and are held in a variable position in the drying basket (41) by means of a pressing device (43).

19- Device according to claim 17 and 18, characterized gekenn¬ characterized in that the drying basket (41) in the drying device (34) is rotatable.

5 20. Apparatus according to claim 17 to 19, characterized gekenn¬ characterized in that in the wall (44) of the hollow chamber (42) nozzles (45) are formed for supplying drying air and diametrically to these exhaust openings.

10. The device according to claim 14, characterized in that the pressing device (35) consists of two stop surfaces (13, 14) arranged at a distance Y parallel to one another, on which the sector surfaces (5, 6) of a sector block (27) can be brought into contact are whose

15 sectors (4, 4a) parallel to the stop surfaces (13, 14) can be pressurized on the segment side by means of pressure transmission means.

22. The apparatus according to claim 21, characterized in 20 that the stop surfaces (13, 14) are designed to be perpendicular to one another.

23- Device according to claim 2.1, characterized gekenn¬ characterized in that the pressure transmission means are designed as pressure "25 stamps (16).

24. The device according to claim 21, characterized in that the pressure transmission means as an elastic bellows-like pressure body which can be filled with a pressure medium

30 (29) is formed, the one on the other

End section (30) of the stop surface (13, 14) arranged stop (31) can be supported.

25. The device according to claim 24, characterized in that 35 in a sector block (27), the pressure body (29) are arranged alternately between the round end portions (22) of the sectors (4, 4a) and the stops (28, 31). ^y oMK.

26. The apparatus of claim 24 and 25, characterized gekenn¬ characterized in that the pressure body (29) are formed as extending over the length of the sectors (4, 4a) against these pressure-resistant hoses (32).

27. The apparatus of claim 24 to 26, characterized gekenn¬ characterized in that on the stops (28, 31) holding means for fixing the position of the bellows-shaped pressure body (29) are formed.

28. The apparatus according to claim 21, characterized in that the stop (28) is arranged horizontally and the stop surfaces (13, 14) are horizontally displaceable to one another and that the segments and tips facing away from the stop (28) between the stop ¬ surfaces (13, 14) mounted sectors (4, 4a) can be pressurized by means of a pressure plate or pressure rail extending over the sector block (27).