Abstract
The invention is related to a method and an apparatus (1) for the fabrication of an endless band (300) containing fiber material, in particular wood, comprising at least the following method steps: providing at least one fiber material block, the fiber material block having a face side; cutting off a plate element (31) from the face side of a fiber material block, the plate element (31) having a cutting surface from the fiber material block, a main surface facing the cutting surface, and an edge surface connecting the cutting surface and the main surface; arranging in relation to each other the cutting surface of the plate element (31) and a fiber material block such that the main surface of the plate element (31) follows the face surface of the fiber material block, wherein said face surface forms the main surface of a further plate element; connecting the plate element and the further plate element by a connecting means; cutting off the further plate element from the face side of the fiber material block. The invention is further related to the endless band (300) and the fiber material block, which is the source for the fabrication of the endless band (300).
Claims
1. A method for fabrication of an endless band from a fiber material block comprising: (a) cutting off a plate element from a face side of a fiber material block, wherein the plate element comprises (i) a cutting surface from the fiber material block, (ii) a main surface facing the cutting surface, and (iii) an edge surface connecting the cutting surface and the main surface; (b) arranging the edge surface of the plate element with the fiber material block such that the edge surface abuts the fiber material block; (c) connecting the plate element and the further plate element to begin fabrication of an endless band; and (d) cutting the further plate element from the face side of the fiber material block wherein the further plate element has (i) a cutting surface from the fiber material block, (ii) a main surface facing the cutting surface, and (iii) an edge surface connecting the cutting surface and the main surface, wherein the plate element and the further plate element are connected before the further plate element is cut from the fiber material block.
2. The method according to claim 1, wherein the fiber material block is comprised of wood.
3. The method according to claim 1, wherein the connecting of (c) utilizes a connecting band.
4. The method according to claim 3, wherein the connecting band is connected to the plate elements by at least one of the following: glue, nails, hooks, screws, hook-and-loop fasteners, adhesive thread, adhesive fibers, adhesive tissue, adhesive foil, adhesive plastic, or plastic melt.
5. The method according to claim 1, wherein (b)-(d) are repeated until a desired length of the endless band is achieved.
6. The method according to claim 1, wherein the arranging of (b) results in the plate element abutting the fiber material block.
7. The method according to claim 5, wherein the arranging of (b) results in the plate element abutting the fiber material block.
8. The method according to claim 1, wherein the step of cutting the further plate element from the face side of the fiber material block further comprises automatic forwarding of the fiber material block towards a connection end of the endless band, wherein the connection end of the endless band is the end that is arranged side by side with the further plate element.
9. The method according to claim 5, wherein the step of cutting the further plate element from the face side of the fiber material block further comprises automatic forwarding of the fiber material block towards a connection end of the endless band, wherein the connection end of the endless band is the end that is arranged side by side with the further plate element.
10. The method according to claim 1, wherein the cutting is performed while the fiber material block is held stationary.
11. The method according to claim 5, wherein the cutting is performed while the fiber material block is held stationary.
12. The method according to claim 1 wherein the plate element includes an edge line at the intersection between the edge surface and the main surface of the plate element, and the fiber material block includes a second edge line at the intersection between the face side and a face surface of the fiber material block, wherein said face surface forms the main surface of a further plate element, and wherein the step of arranging the edge surface of the plate element with the fiber material block further comprises aligning the edge line of the plate element with the second edge line of the fiber material block.
Description
(1) Moreover, additional advantages, features, and applications of the present invention can be derived from the following embodiments of the apparatus and the method according to the present invention, with reference to the drawings. In the following figures, identical reference signs substantially, describe identical components.
(2) FIG. 1a is a schematic side view of a preferred embodiment of the apparatus according to the invention.
(3) FIG. 1b is a schematic side view of another preferred aspect of the apparatus according to the invention.
(4) FIG. 1c is a schematic side view of another preferred aspect of the apparatus according to the invention.
(5) FIG. 2a shows schematically a method for producing a layered block of veneers, which can be used for the method and the apparatus according to the invention, to produce a preferred embodiment of the endless band according to the invention.
(6) FIG. 2b depicts a cross section of a layered block of veneers, e.g. yielded by the method shown in FIG. 2a, which can be used for the method and the apparatus according to the invention to produce a preferred embodiment of the endless band according to the invention.
(7) FIG. 2c illustrates a cross section of a plate element, which was cut from the block shown in FIG. 2b, which can be used for the method and the apparatus according to the invention to produce a preferred embodiment of the endless band according to the invention.
(8) FIGS. 3a, 3b, 3c, 3d, 3e, and 3f show schematically the steps, which are involved to perform, in one embodiment, the method according the invention for producing an endless band according the invention, using the apparatus of FIG. 1 and using the block of FIG. 2b.
(9) FIGS. 4a, 4b, and 4c outline schematically aspects of the method according to the invention and the fabrication of a preferred embodiment of an endless band according to the invention.
(10) FIG. 5a depicts schematically a further block of fiber material, which can be used to produce another preferred embodiment of the endless band according to the invention.
(11) FIG. 5b illustrates schematically a further block of fiber material, which can be used to produce a further preferred embodiment of the endless band according to the invention.
(12) FIGS. 6a, 6b, 6c and 6d show schematically the steps of another preferred embodiment of the method and the apparatus according to the invention.
(13) FIG. 1a shows a preferred embodiment of the apparatus 1 according to the invention. While the method for producing an endless band according to the invention is also exemplarily shown in FIGS. 3a to 3e, the setup of the apparatus 1 is outlined, in particular, in FIG. 1a, with preferred embodiments of the apparatus being illustrated in FIGS. 1b and 1c.
(14) In FIG. 1a, the apparatus 1 has a block holder device 2, a block pressing means 3, and a band processing device 4.
(15) The block holder device 2 has a block forwarding device 5, 6, symbolized by the arrow-elements in FIG. 1a, which is configured to stepwise forward the block in the horizontal direction 7, by a step distance, which is equal to the desired thickness of the veneer, being cut off in a subsequent step of cutting the block 10. The block holder device comprises a fixating and guiding device 9a, 9b for guiding the block during the forwarding process in a restraint-guided manner. The guiding device can be at least intermittently movable or stationary, respectively.
(16) The block-pressing means 3 comprises two pressing members 8a and 8b, wherein the pressing member 8a is vertically movable, as indicated by the double-arrow and the pressing member 8b, which acts as a counter bearing, is stationary. The block-pressing means 3 is used for pressing the block 10 in a defined way and also for holding the block along the cutting direction 11, which is defined by the direction of a cutting device 12, namely a blade 12, which cuts off the plate elements from the face side of the block 11 in a linear motion. The use of the block-pressing means 3 enhances the precision and the quality of the cut, or cutting off the plate elements from the block.
(17) The apparatus 1 is configured to automatically repeat the following three motions, which are preferably, temporarily correlated with each other by fixed time periods: a forwarding motion by the block-forwarding device 5, 6; a pressing motion by the block-pressing means 3; a cutting motion by the cutting device 12;
(18) During said three motions, a band-processing device 4 is used substantially, to connect the plate elements with the connecting means 13, by applying the veneers and/or the plate elements, respectively, to a self-adhesive endless band 13, which is coiled up on a connecting band storage drum 15. The fabricated endless band will then exit the band processing device 4 in the direction of the arrow 14.
(19) The band processing device 4 further comprises the arranging device 16, 17, which comprises a movable frame 16 and a sliding element 17. The arranging device serves to arrange the plate elements and/or the endless band with the block, thereby helping to form the endless band of the invention. The blade 12 can also be seen as a part of the arranging device, because the veneer 30 or the endless band 100, respectively, are also held and arranged by the blade 12. This means, that at least one part of the cutting device can be considered to also be a part of the arranging device, i.e. the arranging device can comprise the cutting device at least in part.
(20) The frame 16 is movable at least along the direction 11, indicated by the double-arrow 19. In the outlined embodiment, the cutting device 12 is fixated to the frame 16 of the band processing unit 4). This, is a preferred embodiment, but however, not mandatory for the present invention. The entire band processing device 4 is movable at least in the direction 11, indicated by the double-arrow 19. This, is also a preferred embodiment, but however, not mandatory for the present invention. With respect to the frame 16, the sliding element 17 is movable in the direction of the fixating force 18 and, within a certain range of tolerance, able to press the plate element against one part of the arranging device, here, against the side surface of the blade 12. The sliding element and the band processing device 4 are configured such, to press the section of the endless band not shown in FIG. 1a, which was fabricated in the previous step, against the blade 12 with a defined pressure, which allows that the endless band slides out in the direction 14 between the blade 12 and the sliding element 17 of the band processing device 4.
(21) In FIG. 1 b, a configuration detail of an apparatus 1 is shown, wherein a sliding element 17 is used to apply a pressure on the end section of a plate element 30, whichtemporarily during the fabrication processforms an end of the endless band. The pressure is sufficient for pressing and connecting the endless connecting band 13 to the plate element of the endless band. An edge of the pressing surface of the pressing member 17 is arranged in opposite to the tip of the cutting blade 12, such that the endless connecting band 13 is substantially simultaneously connected to the face surface 20b (see FIG. 2b) at the position of the blade tip, which penetrates the block 20 of layered veneer, while the further plate element 31 is cut off from the block 20. This way, the endless band is immediately stabilized by the connecting means during fabrication of the endless band.
(22) In FIG. 1 c, a configuration detail of another apparatus 1 is shown, wherein another sliding element 17 is used, which comprises a first sliding element member 17 and a second sliding element member 17. Here, the apparatus and the sliding element is used to guide the end section of the endless band along a length L of the sliding element, during a time t. Thereby, the endless band is allowed to release internal stresses during the time t, before the plate elements are connected by the connecting means, here, the endless connecting band 13. v is the speed of the endless band running along the sliding member during a fabrication step of the endless band, and it is preferably also the cutting speed of the blade 12, penetrating the block 20. The relationship v=L/t is fulfilled, in case the speed is constant. Instead of using a first and a second sliding element members 17 and 17, or additional parts, the sliding element 17 can also be made integral (not shown). In FIG. 1c, the band-processing means of the apparatus further comprises a pressing member 60, e.g. a rotatable drum, which is stationary with respect to the band-processing device, and which can be spring-loaded. Pressing member 60 serves to press and connect the endless connecting band 13 against the plate elements of the endless band. The pressing member is a part of the connecting device of the apparatus. The pressing member 60 is arranged in a distance L from the tip of the blade 12, measured along the length of the endless band. The pressing and guiding of the band elements 30 along the length L and preferably, also the pressing of the endless connecting band 13 against the plate element 30 is supported by the third sliding element member 17, which acts as a counter bearing.
(23) In FIGS. 1b and 1c, the apparatus is respectively shown in a status of operation, directly before the edge surface of the endless band is arranged onto the top of the face side of the block, abutting there. During this operation, the block 20 is pressed and fixated by block-pressing means 8a and 8b.
(24) Referring to FIG. 1a, the fiber material block 10, used for the invention, can have various configurations, which respectively implies that the resulting endless band can have various desired properties.
(25) FIGS. 2b, 4b, 5a, and 5b respectively, show examples of preferred embodiments of a fiber material block.
(26) FIG. 2b depicts an embodiment of a fiber material block and its fabrication by peeling of a wood log, as see in FIG. 2a. The layered block is used in FIGS. 3a to 3f to describe one embodiment of the method according to the invention.
(27) In FIG. 2a, the devices used for fabricating a layered veneer block 20 are not part of the apparatus according to the invention, but could be part of an automatic or semi-automatic station for fabricating an endless band. A tree log 22, is rotated around its length axis, and thereby, an endless veneer 25 is peeled off from the tree log 22 by means of a pressing and sliding member 23 and a peeling blade 24. The endless veneer 25 exits the peeling station in the direction of the arrow 28 and is subsequently clipped by a clipping station 26 into pieces of veneer 27, which are then stored. The veneer pieces 27 are selected, sorted by quality, and cut in the appropriate dimensions. The veneer pieces 27 are aligned and stapled to a stack of veneers, such that the direction of the wood fibers is in parallel, namely parallel to the main surfaces and the long side edges of the stack. The direction of the fibers is perpendicular to the surface of the drawing page, symbolized by the symbols 21. The veneers in the stack, which can be laminated, are pressed together. The stack can be cut again to create a precise rectangular block 20 of stacked veneers. Thereby, the block and the resulting endless band have a texture similar to the natural texture of the cutting surface of a tree log, which was halved along its length. Such a texture is most often desired for aesthetic values.
(28) In FIG. 2c, a plate element 30, 31 is shown, which was produced from the block 20 as outlined in FIG. 2b, thereby, resulting into a plate element, which is constituted of strip elements, which are arranged side-by-side. Generally, a plate element has a cutting surface 30c resulting from the fiber material block, a main surface 30b, facing the cutting surface, and an edge surface 30a connecting the cutting surface and the main surface.
(29) FIGS. 3a, 3b, 3c, 3d, 3e, and 3f outline schematically the steps, which are involved to perform in one embodiment the method according the invention for producing an endless band according the invention, using the apparatus of FIG. 1 and the block of FIG. 2b. In the embodiment depicting the apparatus 1, the only stationary part is the pressing member 8b, while the block holder device 2 with the block 20, the pressing member 8a, and the band-processing device 4 are movable with respect to the pressing member 8b.
(30) In FIG. 3a, the block 20 is the basic material for producing the endless veneer band 100. In FIG. 3a, the block holder device 2, in particular, the fixating and guiding means 9a, 9b, and the block 20 are in their starting position, which represents the position after cutting off a plate element 30, namely a veneer 30, from the face side 20a (see FIG. 2) of the block 20. The veneer 30 has the cutting surface from the fiber material block, which is in FIG. 3a pressed to the blade, and a main surface, facing the cutting surface. This main surface is pressed against the plane sliding surface of the sliding element 17, whereby the main surface is also pressed against the endless connecting band 13, which is positioned between the main surface, and the sliding surface. The edge surface is connecting the cutting surface and the main surface of the veneer 30.
(31) The face surface 20b of the block is positioned within the plane, which is defined by the side surface 8c of the pressing member 8a or the opposing vertical side surface of the blade 12, respectively. The surface 8c acts also as a guiding surface for guiding the blade 12 during the cutting motion, thereby achieving a precise cut from the block. In FIG. 3a, the block 20 is fixated by the movable holder device 2. In FIG. 3a, the block-pressing means 8a and 8b are released once the blade 12 reaches its upper turning position (shown in FIG. 3a). Due to this, the block 20 can be moved by the forwarding device. FIG. 3b shows how the forwarding device of the block holder device 2 forwarded the block 20 with the help of the fixating and the guiding means 9a, 9b in a horizontal direction of the arrow 37 to the right, towards the blade 12. The forwarding is done in a distance, which is equal to the thickness of the veneer 30 and of the endless band 100. Said direction is perpendicular to the direction of the parallel fibers of the block 20. During the fabrication of the endless band, the block is always by precisely the same distance and automatically forwarded in said direction. The position of the band-processing device 4 did not change with respect to FIG. 3a. The operation of the forwarding device of the apparatus 1 is fully automatic.
(32) In FIG. 3c, the block-pressing means 8a and 8b have been approached in the direction of the arrow 38, consequently, the block is pressed (compressed) along said direction and fixated such that a precise cut can be performed.
(33) After fixating and pressing the block as depicted in FIG. 3c, the arranging device 16, 17, which comprises the movable frame 16 and the sliding element 17, will arrange the cutting surface 30c of the veneer 30 from the block 20 such that the main surface 30b of the veneer follows the face surface 20b of the block 20, and wherein said face surface forms the main surface of a further plate element 31.
(34) Generally, it is also possible that the band-processing device 4 (and/or the cutting device 12) is/are stationary and that an additional arranging device is configured to arrange the block to the plate element. Furthermore, it is possible, that the block-holder device comprises lifting means to lift the block towards the possibly stationary cutting device 12. In the embodiment of FIGS. 3a to 3f, the arranging device 16, 17, 12 arranges the veneer 30, which can also be the previously cut plate element (veneer section of the endless band), at the block 20, subsequent to the step depicted in FIG. 3c, such that at least one or otherwise all of the following conditions are fulfilled: i) an edge surface of the plate element 30 approaches the face side 20a of the block 20, following the direction of the arrow 39 shown in FIG. 3d, ii) the plate element 30 abuts on the top side of the face side 20a of the block 20 (shown in FIG. 3d), iii) an edge line of the edge surface of the plate element 30 is aligned with an edge line of the top side of the face side 20a of the block 20 (shown in FIG. 3d), iv) a glue is applied to an area of the top side of the face side 20a of the block 20, before cutting off a further plate element 31; v) the pressure, which is exerted by the sliding element 17 and the surface of the blade 12 to fixate the plate element 30, is reduced, when the plate element 30 abuts on the top side of the face side 20a of the block 20, or shortly after, but preferably, before the arranging device is moved to perform the cutting motion of the cutting device 12, which is fixated to the arranging device; alternatively said pressure remains substantially constant during the fabrication of the endless band.
(35) In FIG. 3e, the face side 20a of the block 20 from FIG. 3a-3d was cut off, and was added as the new plate element 31 to the plate element 30, thereby starting or continuing the fabrication of the endless band, followed by the return of the band-processing device to its starting position (see FIG. 3f). Thereby, the only difference of FIG. 3f compared to FIG. 3a is, that the veneer 30 is replaced by the connected veneers 30 and 31.
(36) During the cutting motion, the face surface 20b of the face side 20a, which will become the main surface of the newly cut off plate element 31, is continuously connected to the endless connecting band 13, which is automatically uncoiled from the drum 15, while the band-processing device 4 is lowered. It is possible and preferred that the cutting process of cutting off the plate element from the block and the action of connecting the connecting means to the face surface of the block start substantially, at the same time, in accordance with the embodiment of the apparatus 1 shown in FIG. 1b. However, it is also possible and preferred that the connecting means is connected with the face surface of the block before or after the cutting process has started, the latter case being in accordance with the embodiment of the apparatus 1 shown in FIG. 1c. It is preferred that the connecting means is connected with the main surface of the previously cut off plate element 30, after having cut off the new plate element 31, and, in particular, that the connecting means is not connected to the block, but is preferably, connected the endless band while the endless band is passing the arranging device (FIG. 1c).
(37) The connecting means is step wise and/or in part continuously applied to the block and/or to the plate element. The sliding element 17 or 17, preferably, causes a defined status of friction of the endless band passing the arranging device. The status of friction is adjusted such that the specific compressibility of the block material is recognized and that all endless band are of equal quality, in particular, without substantial variations of the inner stress of the endless band.
(38) Preferably, the synchronization of the forwarding motion, of the arrangement motion, and of the cutting motion is automatically performed by the apparatus according to the invention. The apparatus is configured such that the forwarding device and/or the arranging device, and/or the cutting device are working synchronized, which allows for a substantially, continuous operation of the apparatus, preferably, fabricating an endless band with seamless connected plate elements.
(39) FIGS. 6a to 6d show the steps of a preferred embodiment of the method according to the invention, using a preferred embodiment of the apparatus according to the invention. Compared to the embodiments in FIGS. 1a, 1b and 1c, the embodiment in FIGS. 6a to 6d uses a different time for connecting two adjacent plate elements of the endless band with the connecting means, with respect to the time of starting and ending the cutting process:
(40) In the embodiment of FIGS. 6a to 6d, the connecting means, namely the endless connecting band 113, which is already connected to the endless band 300, is connected to the face surface of the fiber material block 20, before the further plate element is cut off from the block. In detail: In FIG. 6a, the endless band 300 is already provided with the endless connecting band 113. The arrangement device of the apparatus is not shown in FIGS. 6a to 6d.
(41) In FIG. 6b, the block 20 has been forwarded by the distance to be cut off from the block 20. The endless band 300 with the endless connecting band 113 is arranged at the block 20 such that the edge surface of the endless band 300 is moved to the top surface of the face side 20a of the block. This movement is indicated in FIG. 6b by the arrow pointing downwards. During this movement, the endless connecting band 113 is not yet connected to the face surface 20b of the block.
(42) In FIG. 6c, the edge surface of the endless band 300 has abut on the block, and the connecting band 113 is pressed and thereby connected to the face surface 20b of the block by the pressing means 117, which acts as the connecting device. The pressing means can be heated to apply heat to the connecting means. This way, the endless band 300 is temporarily connected to the block 20, before the further plate element is cut off from the block in FIG. 6d.
(43) FIGS. 4a, 4b, and 4c show a preferred embodiment of the endless band, wherein the sequence of the plate elements 41, 42, 43 within the block 40 is predetermined such that a predetermined sequence is also achieved in the endless band, which is fabricated from said block 40. Three types of veneers are shown in FIG. 4a, namely a first veneer 41, which is five times in stock, a second veneer 42, which is three times in stock, and a third veneer 43, which is twice in stock. The object of this embodiment is to form an endless band with homogeneous properties from the veneers in stock such that a minimum of refuse material of veneer is produced, while at the same time a maximum length of the endless band is achieved. In the endless band 200 according to the invention, which preferably was fabricated according to the method according to the invention, preferably using the apparatus according to the invention, a homogeneous distribution of the veneers in stock is achieved, resulting in an endless band of homogeneous properties. These properties can, for example, be the visual appearance, which is created by a periodic arrangement of the sequences of the veneers 41, 42, 43 in the block 40. Said sequences of the block 40 are specifically calculated to optimize, e.g., the distribution of brightness of the surface of the endless band 200 with respect to its homogeneity. An additional property could be mechanical property, for instance if some veneers 41 have a higher compressibility than other veneers 41 and 42, resulting in a uniform mechanical load capacity of the endless band.
(44) Method for Forming a Fiber Material Block, in Particular, an Endless Fiber Material Block 50 from Fragments
(45) FIG. 5a shows schematically a section of an additional block of fiber material, which can also be used to produce another preferred embodiment of the endless band according to the invention. Block 50 contains fragments of fiber material: therefore, veneer strips and/or plates 51 (and/or otherwise shaped fragments) are arranged in a staple block 50, which is supported onto a support platform 52. The fragments within the block 50 are stacked and distributed randomly, and are overlapping each other. The number of fragments within each cross section of the block 50 is substantially, the same, within a range of tolerance of less than 10%, 5%, 2%, or 1% or different.
(46) In FIG. 5b, the block 50 of FIG. 5b was compressed, such that within the overlapping regions of the fragments, and within the positions of reduced density of fragments substantially, no material defects of the block 50 exist. Such a fiber material block 50 can be produced endlessly (hence, endless), because the steps of adding and compressing fragments can be performed continuously. Therefore, an endless band of extended length can be produced easily by using a blocklike block 50and the apparatus according to the invention. The resulting endless band has substantially homogeneous properties along the width and the length of the endless band, in particular it has a homogeneous visual appearance, corresponding to the spectrum of fragments used for forming the block 50.
(47) A particular advantage of the block 50 and of the method for forming the block 50 is, that small fragments of arbitrary format and arbitrary thickness can be used, which preferably, do not comprise a cutting surface or any glue joining the layers of the block, which is usually required by layered blocks like the block 20. Therefore, the fragments can be of refuse material or of residual material, which can be chipped or otherwise treated before forming the block 50. This way, also a solution was found to exploit or recycle wood and veneer refuse material. Generally, fragments are not restricted to parts which are generated by separating larger parts, however, it is preferred, that this would be the case. Preferably, a fragment is a small part, preferably, smaller than the height HB (or HB*0.5 or HB*0.25 or HB*0.1) of the block to be fabricated, preferably smaller than the following preferred ranges of its dimensions height H, width W, and length L:
{0.1;0.5;1;2;3;4;5} mm<=H;W;L<={1;5;10;15;20;30;50;100;150;200;300;500} mm;
(48) The method for forming a fiber material block, in particular, an endless fiber material block 50 from fragments, in particular, sheet fragments of fiber material, in particular, wood, comprises the step of the manual or automatic laying of fragments, or packages, or fills of fragments. Known density-sensing methods and thickness sensors can be used to monitor and control the number of fragments. The fragments can also be processed to have a uniform shape and/or size, and/or mass. Moreover, it is also possible to use position sensors, e.g. optical sensors, and/or electrical control devices, and/or manipulation means for manipulating the position, and/or the orientation of the fragments within the bed of fragments, wherein the manipulation means can be arranged downstream after the laying of the fragments. Said manipulation means can also be found within the generally known production of OSB-boards. Here, strips of wood, which are sifted and then, oriented on a belt or on wire cauls, to form a mat, are used. An example for an OSB-board fabrication process can be found in WO 1999/047321 A1. For creating the block 50, stapled or laid fragments can be pressed. A glue, a water-comprising adhesive, or any other glue can be used respectively, to connect the fragments with each other. One advantage of this method is the high homogeneity of the resulting block 50, which increases with decreasing format, size, or volume of the fragments. Said method is strongly applicable for automation.
(49) Instead of using veneer fragments, it is rather preferred that the block comprises veneer-like chips, similar or equal to the chips, which are used for OSB-production. A further advantage of this method is that the known, OSB-manufacturing technology can be used, at least in part, to form blocks 50, using wood chips (OSB-chips) and the known OSB-system engineering.
(50) According to a further embodiment of the block 50, instead of using a closed structure of fragments within the block, e.g. instead of using a compressed structure substantially without gaps and material defects, the fragments can be arranged such that hollow spaces are provided between a substantial fraction of or substantially, between all of the fragments. Said hollow spaces can be randomly distributed over the entire block volume, which would be easier for fabrication, or they could be positioned in a substantially, defined manner over the block volume, which would make designing and predicting the properties of the resulting block and the endless band, easier. Even in this case, the block can still be compressed. Also, a glue could be provided to connect the fragments with each other. The block with hollow spaces has a reduced density, and is preferably, used to fabricate a lightweight-endless band, using the method according to the present invention. Such a lightweight-endless band can be used to produce lightweight-building parts, e.g. the core elements of lightweight-plates. Combining at least one endless veneer band as an endless cover band with at least one lightweight-endless band to form a layered endless band, can then result in a layered endless-lightweight band.
(51) In one example of producing a block 50 from fragments: the veneer fragments can have a length of 50 mm, a width of 20 mm, and a thickness of 1.8 mm. In a glue drum, the veneer fragments are then provided with a dispersion adhesive. Using a belt, said treated veneer fragments pass through a manipulation device to align the orientation of said veneer fragments. Additionally, they pass through a mat-forming device, in which a mat of 300 mm height and width of equally oriented veneer fragments, is put out. Said mat is then compressed by a pressing means to a height of 240 mm, and provided with water vapor, to reactivate the dispersion adhesive and to cause hardening of the mat. Simultaneously, the veneer fragments become plasticized by the vapor and in cooperation with the glue such that the compression becomes fixated. The block, fabricated this way, is immediately used, while the block is still hot, to generate an endless band of 3 mm thickness. Preferably the block has still a temperature of 30-95 C. or 50-85 C. during fabrication of the endless band. The resulting endless band has a fraction of 45 vol % of hollow spaces between the veneer strips (similar to FIG. 5a) and is then used to form a core layer for the fabrication of a lightweight-sandwich elements.
