JPH0342167B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION In the present invention, each layer constituting the laminated plywood is composed of a plurality of veneer veneer groups (hereinafter referred to as veneer veneers), and the veneer groups are moved in a certain direction to a predetermined dimension. This relates to plywood that is made by shifting one layer at a time and laminating and bonding.

In Japanese Patent Application Laid-Open No. 58-98202, the applicant has
Alternatively, plywood is made by laminating and bonding a plurality of veneers shifted by a predetermined dimension in the direction of their fibers, and in JP-A-58-151201, all or a plurality of veneers are shifted by a predetermined dimension in the direction perpendicular to their fibers. We proposed plywood that is made by laminating and gluing the sheets one by one.

However, with any of the above plywoods, most of the veneers have their fibers aligned in the same direction, so it is not possible to obtain sufficient strength in the direction perpendicular to the fibers, and the strength deteriorates over time. It had a tendency to warp easily due to drying, moisture absorption, etc.

The purpose of the present invention is to improve the plywood that the applicant previously proposed and applied for, and which improves the strength of the plywood in a well-balanced manner in the direction orthogonal to the fibers, and which can prevent warping during drying and moisture absorption. Our goal is to provide the following.

The present invention will be described below with reference to Examples.

1A and 1B are perspective views showing groups of veneers constituting each layer of plywood according to the present invention, and FIG. 2 is a perspective view showing the plywood. In the figure, 1 indicates two veneers 2a and 2b This is a bonded veneer as a group of veneers formed by joining the veneers 2a so that their fiber directions are perpendicular to each other, and the width of the veneer 2a in the fiber direction and the width of the veneer 2b in the direction perpendicular to the fibers are a predetermined dimension l1 described later.
longer, preferably at least 5 times the thickness of the veneer, and even
The length is about 15 to 150 times longer, and scarf cut surfaces having an appropriate scarf cut length are formed at the ends 1a and 1b of the bonded veneer 1.

In addition, 3 in the figure indicates 2 veneers 2a and 2b whose fiber directions are perpendicular to each other with respect to the veneers 2a and 2b constituting the bonded veneer 1 described above.
It is a joined veneer formed by joining two veneers 4a and 4b, and the width of the veneer 4a in the direction perpendicular to the fibers and the width of the veneer 4b
The width in the fiber direction is longer than a predetermined dimension l1 described later,
Desirably 5 times or more the thickness of the veneer, more preferably 15 or more.
In addition to making the bonded veneer 3 about 150 times longer, a scarf cut surface having an appropriate scarf cut length is formed at the ends 3a and 3b of the bonded veneer 3.

The plywood 5 is made by shifting the bonded veneers 1 and rows 3 by a predetermined distance l1 to be described later in a certain direction at a ratio of one bonded veneer 3 to each bonded veneer 1 described above, and Exposed end 1a or end 3a
and the end portion 3b exposed on the other surface, or the end portion 1b, are positioned so as to substantially face each other, and are bent in the thickness direction of the plywood 5 every predetermined dimension l1, extending parallel to the front and back surfaces thereof. In this state, a desired number of veneers on the front and back sides are laminated and bonded to another veneer with the fiber directions perpendicular to each other, and cut to a desired size including the bent portion. The figure shows an example of the 5-ply plywood.

The above-mentioned predetermined dimension l1 is set to approximately l1=L/N, where L is the length of the bonded veneers 1 and 3 in the horizontal direction in the drawing, and N is the number of stacked layers.

Note that the plywood 5 shown in FIG. 3 is obtained by laminating the respective bonded veneers 1 and 3 in the same manner as described above, without scarf cutting the ends 1a, 1b, 3a, and 3b of the bonded veneers 1 and 3. It is made by gluing, and there are some recesses on both sides compared to the plywood 5 shown in Fig. 2, but its flatness is generally good, and aesthetics can be sought for there, so there is no problem in practical use. Something,
Further, if necessary, it is also possible to easily seal the recessed portion or form a groove in an arbitrary shape.

Furthermore, compared to the plywood 5 shown in FIGS. 2 and 3, the plywood 5 illustrated in FIG. 5, which is laminated and bonded in such a way that they overlap, and has small convex portions on both sides.
It is made of ply plywood, and if necessary, the small protrusions can be left as is to create an aesthetic appearance, or the small protrusions can be processed into a protrusion of a desired shape, or the two-dot chain line in the figure As shown, it can be easily removed by sanding, cutting, etc., and it is also possible to obtain excellent flatness like the plywood shown in FIG. 2.

Although not shown, the end 1a of the bonded veneer 1 and the end 3 of the bonded veneer 3 are located at other positions on the plywood 5.
The same is true when there is an overlap with b.
When the small convex portion is removed, the end of the edge 1a of the bonded veneer 1 is exposed on the upper surface shown in FIG. It is also possible to obtain plywood 5 in which the end of the end portion 1a is exposed on the upper surface by laminating and bonding the cut surfaces facing outward.

In addition to the lamination ratios of the bonded veneers 1 and 3, it is also possible to alternately laminate the bonded veneers 1 and 3 one or more times, or to stack the bonded veneers 1 and 3 alternately, for example. It is possible to construct the plywood 5 even with a desired lamination ratio (arrangement state) of laminating three sheets and then one or any plurality of bonded veneers 3.

Further, FIGS. 5 to 8 illustrate various laminated states before being laminated and bonded to the 5-ply plywood 5, and the plywood 5
The illustrations illustrate the facing relationship of the end portions 1a and 1b of the bonded veneer 1 on the front and back surfaces of the board, and examples of processing aspects of the end portions 1a and 1b, and in any case, the plywood according to the present invention This can be implemented as 5.

FIG. 9 illustrates the basic manufacturing method of plywood 5 according to the present invention. The ends 3b of the veneers 3 are overlapped as shown in the figure, and the adhesive is applied by the spreader 6.

The application of the adhesive is carried out by leaving a non-adhesive area on one side of the bonded veneers 1 and 3, and in the next lamination process B, the bonded veneers are bonded with the non-adhesive area exposed. 1 and 3 are stacked one on top of the other, shifting them as shown in the figure.

The laminated bonded veneers 1 are transported to a temporary bonding process C which has an intermittent or continuous cold press (not shown) or a device that temporarily fixes the relative positions of the bonded veneer layers by appropriate means. Then, in the next cutting process D, it is cut to a predetermined size.

Then, in a bonding process E using an adhesive curing device (not shown) such as a hot press, the bonded veneers are bent in stages in the thickness direction of the plywood and extended parallel to the front and back surfaces of the plywood. The bent parts are bonded together to produce plywood having the laminated state described above.

Regarding the adhesive application step A,
As in the process example described above, bonded veneer lamination process B
In the case where the adhesive applied to the bonded veneers is to be laminated while being shifted one after another without exposing the adhesive at all or almost, the adhesive application step A has an appropriate width. It is necessary to apply the adhesive while ensuring areas where the adhesive is not applied.

Incidentally, FIG. 10 shows a partially enlarged view of the laminated state of bonded veneers 1 and 3 in lamination process B.
In this way, the edge of the end 1a of the top-layer bonded veneer and the edge of the end 1b of the bottom-layer bonded veneer are placed in a facing relationship as shown in the figure (in this case, the opposing dimension is referred to as 0). In the lamination step B, in which the bonded veneers 1 are laminated together, each bonded veneer 1 is sequentially exposed from the edge by a dimension of L/N (in the case shown, N is 4), and the bonded veneers 1 to be used are , as well as the presence or absence of end processing in step 3, the extent of the processing, and other reasons. (approximately 15 times or less than the thickness of the veneer).
As a result, the exposed dimensions also increase or decrease, and in order to avoid applying adhesive to these exposed surfaces, it is necessary to secure areas where adhesive is not applied.

Securing such adhesive-unapplied areas can also be achieved by controlling an adhesive application device such as a spreader, curtain coater, or film adhesive supply device (when using a film adhesive).
In practical terms, it is very practical to place the end 1b of the bonded veneer 1 and the end 3a of the bonded veneer 3 in an overlapping state as shown in Fig. 11, and then apply the adhesive using various types of ordinary adhesive applicators. It's very convenient.

In this case, the overlapping length of the bonded veneers is set based on the exposed surface dimensions in the lamination process B described above,
11 shown in the figure is the overlapping length when the L/N is exposed, and when arbitrary facing dimensions S and S' are set, the overlapping length will increase or decrease accordingly as shown by the two-dot chain line in the figure. Set.

Of course, it is basic that the dimensions of the non-adhesive part and the dimensions of the exposed surface completely match, but in practice, the former should be slightly smaller or larger to reduce errors in each process or between the two processes. deal with.

In any case, the lamination work in the lamination process is the same, but the work of overlapping this type of bonded veneer is the 12th work.
If the work is carried out automatically, semi-automatically, or manually on a conveyor with a positioning member, such as the conveyor belt 8 having the stopper 7 illustrated in FIGS. It can be implemented by

Furthermore, as illustrated in FIG. 14, the drive source 9 drives a conveyor such as the one prepared for the adhesive application process A, and furthermore, the same drive source 9 drives the conveyor such as the one prepared for the lamination process B via the deceleration mechanism 10. If such a configuration is adopted to drive the conveyance body, the relationship between each process is extremely stable with the uniform setting of the speed reduction mechanism 10, and the error between the two processes becomes a fixed value.

In this case, there is no particular problem even if the drive source 9 is turned on and off and driven intermittently, so it is easy to provide an intermittent cold press in the temporary bonding process C in the process shown in FIG.

In addition, if the drive source applied to the bonded veneers is allowed to be exposed in the bonded veneer lamination step B, or if it is assumed that the drive source is actively exposed, the adhesive application step is not particularly detailed. Adhesive is applied without properly securing the non-adhesive area.

For example, in the example shown in FIG. 9, an adhesive application process is configured in which the bonded veneers 1 and 3 are sequentially supplied to the spreader 6 without overlapping them and the adhesive is applied to the entire surface of one side.

In this case, in the process B of laminating the bonded veneers, the adhesive will be exposed almost continuously on the bonded veneers exposed on one side, but this is not acceptable for the plywood to be manufactured. Alternatively, it is also possible to use the exposed adhesive to bond other veneers such as so-called original boards, decorative boards, boards, etc., for example, in order to wipe away unevenness on the plywood surface. Of course, desired laminated materials can be laminated and bonded not only to one side of the plywood but also to both sides.

Therefore, the adhesive application step A is carried out, and the desired exposure of such adhesive is carried out in the lamination step B, and other laminated materials are further laminated in the lamination step. It is also possible to proceed to the next step.

As described above, the specific structure of the adhesive application process that embodies the plywood manufacturing method according to the present invention is determined based on the relationship with the next lamination process, and there are various examples other than the above-mentioned example. It is composed of the following form.

In addition, the adhesive application process and the lamination process are on the same plane other than being connected as shown in FIG.
The adhesive application process may be arranged at the upper part in the conveyance direction, and the lamination process is arranged at the lower part in the conveyance direction, and the two processes may be connected in a desired form if necessary.

Furthermore, in the example of FIG. 9, if instead of the temporary bonding process C, the bonding process E having a continuous hot press is connected to the laminating process B, the production of plywood according to the present invention can be carried out continuously, and the process can be carried out as desired. When the length is increased, cutting is performed in cutting step D.

As explained above, the present invention provides a plywood that improves the strength in a well-balanced manner in the direction perpendicular to the fibers and prevents warping.

In addition, the wood species, thickness, size of the veneer to be used,
Changes in general matters related to plywood, such as the positioning of cracks on the back of laminated veneers, the number of plies, the adhesive used, and the moisture content of veneers, should be made in accordance with common practice, but there are no particular restrictions. It's not something you do.

In addition, in the embodiment, the manufacturing process etc. of the veneer group of each layer constituting the plywood has been described by illustrating the bonded veneer 1, but it is not limited to the group of veneers that have been bonded in advance, and multiple veneers A group of veneers is formed by arranging the veneers in an unbonded state and with the fiber directions of the veneers located at one end and the other end in a predetermined direction perpendicular to each other, and It is also possible to use a process of manufacturing plywood by laminating a plurality of veneer groups, and it is of course possible to create a so-called tunnel when arranging each veneer.

Furthermore, in the embodiment, the plywood 5 is a bonded veneer 1 formed by bonding two veneers whose fiber directions are orthogonal to each other;
and 3 were laminated and bonded, but by using a veneer group consisting of three or more veneers arranged so that the fiber directions of the veneers located at both ends are perpendicular to each other,
Even plywood formed by laminating and bonding an arbitrary number of veneers on the front and back surfaces of the plywood with respect to other veneers in a relationship perpendicular to the fiber direction can be implemented as the plywood according to the present invention.

[Brief explanation of drawings]

1A and B are perspective views showing bonded veneers constituting the plywood according to the present invention, FIG. 2 is a perspective view showing the plywood, and FIG. 3 is a perspective view showing a modified example plywood of the present invention, FIG. 4 is an explanatory diagram showing a part of another embodiment of plywood, FIGS. 5 to 8 are explanatory diagrams showing the laminated state of bonded veneers, FIG. Figure 10 is an explanatory diagram partially enlarged to show the laminated state of the bonded veneers, Figure 11 is an explanatory diagram showing the state of adhesive application, and Figures 12 and 13 are for stacking the bonded veneers together. FIG. 14 is an explanatory diagram showing a state in which the adhesive application process and the lamination process are driven by the same drive source. In the figure, 1 is a bonded veneer as a group of veneers, 1a・1b
2a and 2b are the ends of the joined veneers, 3 is the joined veneers as a group of veneers, 5 is the plywood, and l1 is a predetermined dimension.

Claims (1)

[Scope of Claims] 1 Each layer constituting the plywood includes a plurality of veneer veneers arranged in a predetermined direction, and a veneer veneer at one end and a veneer at the other end of each layer in the predetermined direction. The veneers are arranged perpendicularly to each other, and the veneer veneers in each layer are shifted by a predetermined dimension in the predetermined direction with respect to the veneer veneers in the other layers, and Each plywood is bent in the thickness direction and extends substantially parallel to both sides of the plywood, and an arbitrary number of veneer veneers at the end of the plywood are bent into veneer veneers at the other ends of the plywood. A plywood board characterized in that it is laminated and bonded with the fiber directions orthogonal to each other, and cut to any size including the bent portion.