FI73163C - FOERFARANDE OCH ANORDNING FOER STAPLING AV SKIKTHALVFABRIKAT AV TRAE. - Google Patents

Description

! 73163

The present invention relates to a method and an apparatus for stacking a multi-blank, which method is of the type given in the preamble of claim 1 and which device is of the type given in the preamble of claim 5.

The currently commonly used multi-layered wood is made by extending the turned wood veneers in the middle of the multi-layered wood, about 3 mm thick, with a butt extension, as described in Finnish patent application 2889/72. The outermost veneers, about 1 1/2 mm thick, are in turn extended with a glue joint.

Plywood has been manufactured for a long time in such a way that the veneers are first glued to a continuous web by joining suitable pieces together in a separate splice press, after which the webs are glued on top of each other in a separate working step. The extension takes place by beveling the ends of the veneers at an angle of inclination of 1:20 to 1:10, applying glue to the inclined joint surface and passing the thus joined joint through a press which presses the joint of the joint over its entire width and slightly over it in the longitudinal direction. A thermosetting plywood adhesive is used as the adhesive, whereby the pressure of the press is quite high and the temperature is also high. Such an extension corresponds to the normal plywood manufacturing process and is described in FI patent application 21/66.

Another known multi-ply structure is one in which all veneers of the same thickness are extended by an adhesive joint as described in FT patent publication 59547. This product is sold under the trademark "Micro-Lam".

2,731,631 DE 905 666 describes a method for producing plywood, for example, by stacking veneers in a completely undefined manner, but thus apparently by hand, layer by layer first the lowest layer, to which joints are also made in oblique joints if necessary, and then other layers way. The result is a single piece of plywood that is transferred as such to a press to cure my glue.

Furthermore, the possibility of producing multi-layered wood with chamfered joints is mentioned in FI patent publication 59,547. The veneers must be more than 2.5 m ("a little over eight feet") long and be placed and aligned at the same time on a reciprocating conveyor with a stroke corresponding to the length of the veneers.

The object of the present invention is to simplify the continuous production process of multi-layer wood so that the initial gluing of the veneers at the ends takes place during the atomic process. An obliquely sawn joint surface is used for connection.

The product of the desired length according to the invention can be made of veneers of varying lengths, however, so that the veneers are of equal length in each stage of the manufacture of the same product. Among other things, "Micro-Lam" must be made of veneers at least 2.5 m long, as otherwise the method cannot be controlled. This possibility to vary the length of the veneers according to either the product requirements or the raw material quickly and within wide limits is based on the method and device according to the invention, and is not possible e.g. in the method of FI-59 547.

The above-mentioned advantages are achieved by means of a method and a device, the characteristic features of which are given in the appended claims.

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The invention will now be described in more detail with reference to the accompanying drawings, in which Figure 1 shows a manufacturing method and an apparatus according to the invention in a schematic and greatly simplified side view, and Figure 2 also shows a product according to the invention in a side view.

In Fig. 1, reference numeral 1 denotes a violin warehouse. From this warehouse, the veneer is transferred via a conveyor and an alignment device to a miter saw table 2 with a miter saw blade 3, which performs sawing transversely to the autumn direction of the veneer.

From this the sawn veneer continues to calibrate the length to the table 4, where the so-called the drawing blades 15 perform a length calibration to a certain extent and at the same time remove the very thin and usually uneven oblique cut resulting from the oblique sawing from both ends of the veneer. Thereafter, the veneer continues to the gluing table 5, where the glue is applied to the upper surface of the veneer and also to the upwardly open surface. Although the imina is shown in the figure as a nozzle from which the glue is sprayed on the surface, by any other known method. After applying the glue, the veneer continues its journey to a series of three conveyors 7, 8, 9, which conveyors are successively and overlapping under each other, however, so that the first conveyor 7 is fixed. Reference numeral 10 denotes a barn table on which a multi-layered blank is stacked before it is hot-pressed.

Stacking is performed as follows. The veneer, which comes from the glue application, arrives at the conveyor 7, from where it continues its journey to the conveyor 8 and further to the conveyor 9. The stacking of the Kerto wood blank starts at the far right edge of the product. Two lengths of veneer are stacked on the lowest layer, 73163 4 after which the second layer is started with one veneer and then a third veneer is stacked on the first layer, a second veneer on the second layer and a first veneer on the third layer. This is continued until the entire thickness of the multi-layered blank is reached. So, in the end, the multi-threaded blank will be on the far left edge, where even the last veneer is stacked in place. It is clear that the upper surface of the top layer must not contain glue, therefore the glue applicator 6 applies the glue only to the gluing surface of the top violin layer or the glue is applied to the gluing surface in a separate device.

The basic idea of the invention is the realization of how to make the oblique joint settle in place so that the alignment is accurate. Thus, it was realized that the incoming veneers are driven against the stacking stop 12, which stop automatically moves to its correct position, which is directly below and above the beginning of the oblique start of the previous edge of the previous veneer; i.e., so that the corresponding chamfers of the veneers at the front and rear come into vertical alignment. At this point, the veneer gripping members 11, which press the incoming veneer into place on top of the previous veneer, have their chamfered surfaces facing each other, while aligning the veneer stacking response 12 at a designated location. The preform is then compressed into a pile by a pre-press 13, which follows the stacking response a short distance therefrom and thus ensures that the preform remains immediately in place, leaving each veneer in place.

Once the last veneer has been cold-pressed into place, the multi-layer blank is transferred to a hot press 14, which cures the adhesive and thus the finished product. The product is cut to size only after it is ready.

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According to the invention, the joints of the veneers can be placed, for example, about 10 cm apart. The method and apparatus according to the invention are automated so that the response automatically moves in the desired direction to wait for the next incoming veneer at the point where it is to be placed.

The whole process also works automatically, so that it only needs to be intervened when there is a disturbance in it. By using veneers of uniform length and precisely calibrated to their own length, it is possible to obtain such that the joints in the nearby layers of violin are not very close to each other. So the multiplication tree becomes strong.

Although the basic idea of the invention has been described above in a very simplified form, omitting all such parts which are not of primary importance for understanding the invention, the invention must nevertheless be understood to the extent provided by the scope of the claims. Thus, for example, all conveyor units are missing from Figure 1 and the various process steps are indicated only by lines, but the essential features are nevertheless shown schematically in the figure. Of particular note is the schematic representation of the attachment response 12 and the gripping member 11. These bodies can be constructed in a manner obvious to those skilled in the art, which is not further elaborated in this presentation.

The slope of the bevel joint is affected by many factors, such as the quality of the wood used, the thickness of the veneer, the beveling technique and other practical conditions. It is therefore difficult to give any absolute values for the slope. However, the extremes could be considered to be about 1: 1 at the steepest end and about 1:30 at the gentlest end. However, in the most common cases, the oblique used is about 1:10 to 1:20, i.e., approximately the same oblique used to make plywood, with the veneers joined together in a separate step.

Claims (7)

1. Multi-ply wood is a stacking method in which the ends of equally long veneer pieces to be stacked one on top of the other are chamfered to provide an oblique extension between successive veneer pieces in the pile, and the chamfered upward extension surfaces are later in the next hot pressing step, characterized in that the veneer piece arriving at the stacking table is stopped by driving its leading edge against the stop placed at the top of the chamfered surface of the previous veneer piece in the stack a, whereby an oblique joint is formed with the above veneer and the pressing point is attached to the veneer below. A method according to claim 1, characterized in that the stop is automatically adapted to stop the incoming veneer at the next joint, and in that the pre-press is adapted to move together with the stop. Method according to Claim 1 or 2, characterized in that the veneer has been length-calibrated and the uneven extreme parts of the so-called using drawing blades. A method according to claim 1, characterized in that the ends of the veneers to be joined are chamfered to a chamfer of about 1: 1 to 1:30, preferably about 1:10 to 1:20. 5. A multi-layered wood blanket is a stacking device in which a sufficiently large number of suitably chamfered pieces of veneer is stacked one on top of the other on top of a fixed stacking table so that the upper surface of the veneers for gripping it on the lower surface of the next veneer layer, characterized by a stop (12) which stops the incoming veneer at the upper edge of the chamfered part of the previous veneer in the pile and presser or gripping members (11) pressing the chamfered end of the veneer into the stop. Device according to Claim 5, characterized by a bite of a line (13) which presses the bevelled ends of the veneers then pressed against their base, the veneers adhering to one another and their joint being adhered to the underlying veneer. 6 73163 Patent Requirements Device according to Claim 5 or 6, characterized by drawing blades (15) which make the veneers fixed in size and remove the extreme ends of the oblique cutting surfaces of the veneers 1.