JPS5845006A - Method of bonding and molding small-diameter wood - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a method for bonding and forming small diameter wood.

Conventionally, in order to make effective use of small-diameter trees, a technique 1 for increasing the diameter of a large number of small-diameter trees by making the fiber direction the same is disclosed in Japanese Patent Application Laid-Open No. 56-70902 (title of invention:
There is a method for manufacturing veneer for plywood.

However, the above technology has the following drawbacks. In other words, when filling and gluing a filler into the gap between two pieces of small-diameter wood in one bundle, it is practically difficult to match the shape of the filler to the gap, and as a result, the shape of the filler and the small-diameter The strength of the bond with the tree and the strength of the large-diameter log itself after bonding become unstable.

The present invention fundamentally solves these difficulties and provides a technology for increasing the diameter of small-diameter wood that can ensure more stable adhesive strength.3 The details thereof are as follows.

What is shown in FIGS. 1 and 2 is an example of a method for making a small-diameter tree 1 into a cylindrical shape with a large diameter.
As is clear from the figure.

First, a large number of small-diameter trees 1 are bundled together in a formwork consisting of a lower formwork 2 and an upper formwork 3, with adhesive applied to their outer peripheral surfaces, and with the fibers generally in the same direction (first state).

Next, the internal volume of the formwork is reduced using a hydraulic press 4 to cause deformation of each small-diameter wood 1, and the gaps between the small-diameter wood are filled, and this state is maintained at least until the curing of the adhesive is completed using a stopper 5. 2) and adhesively mold.

In this example, we used stripped core of larch generated from veneer lace as the small diameter tree, so the cross section is shown as an equal circle in Figure 1, but if thinned wood is used, the cross section will be irregular. becomes. In both cases, after the compression process, as shown in Figure 2,
The cross-sectional shape changes to some extent, taking on a hexagonal shape, and the adhesion area between each small-diameter piece of wood increases. Incidentally, in the case of 9 cases, paying attention to the cross-sectional area, the initial internal volume of the formwork was set to 10
If it is set to 0, then cores having a volume of 75% are bundled together in the mold, and then the volume inside the mold is reduced to 60% and adhesive molded, so in reality the core itself is 20%. It has a tortoise shell shape with its volume reduced by 50% due to compression. Of course, since it is made of wood, the volume should be reduced to about 50 inches (although it is possible to do so, pointless and excessive compression will result in large losses, and in this example, the voids between the cores are This is carried out with the aim of deformation to the extent that it will eliminate the damage.

When carrying out the present invention as an adhesive molding with almost eliminating the gaps between the small diameter trees in order to reach the maximum bonding area between the small diameter trees as in B, the species of the small diameter trees may also have some effect. However, the initial filling of small diameter wood bundled into the formwork 1
Assuming that the rate is A (75% in the case of the above example), the internal volume of the formwork is approximately the square of A (approximately 56% in the case of the above example) or less (approximately 56% in the case of the above example). As a general guideline, it is recommended that the diameter of the small-diameter wood in the formwork is reduced to 1 or less, causing deformation of the small-diameter wood within the formwork. In addition, when adhesive molding is performed to such an extent that some voids 11 remain between the small-diameter trees 1 as shown in FIG. It is desirable to reduce the internal volume and thereby ensure a sufficient adhesion area between the small-diameter trees for practical purposes. Note that the above guideline is for the case where a large number of small-diameter trees are enlarged to a simple shape such as a cylinder or a prism. In any case, 8 in Figure 1
As instructed in , the cross section is triangular in the space between each small diameter tree.

Replenishment material 7 of an appropriate shape such as a square 9 circle, such as tree branches, sawn timber products, sawn waste, veneer, veneer waste, etc., or appropriately distribute small diameter trees of various sizes and shapes. Then, bundle them together, or furthermore.

The filling rate A can be increased by pre-processing small-diameter wood into an appropriate shape and then performing thorough bundling.

It is possible to further reduce the extent to which the internal volume of the formwork is reduced, and to reduce substantial loss due to compression.

In addition, in carrying out the present invention, it is important to cause some deformation to the small-diameter wood to ensure an enlarged bonding area.
It is effective to soften small-diameter wood in advance, and if necessary, perform preliminary treatments such as boiling, steaming, and microwave heating. Such small-diameter wood is considerably easier to compress and deform. Yet again. When compressing small-diameter wood after bundling it into a formwork, it is also effective to include an overcompression process in which the internal volume of the formwork is temporarily reduced excessively, and then restored and maintained at a predetermined compressed state. It is. For example, in the embodiment described above, during the transition from FIG. 1 to FIG. If this operation is performed once or an appropriate number of times, the deformation of the small-diameter wood changes from an elastic state to a considerable plasticity, and it not only maintains a stable shape even after adhesive forming. , the bond between small-diameter trees is also stabilized.

However, after being removed from the formwork, the large-diameter glue-molded logs obtained by the present invention maintain a predetermined state due to the strength of the adhesive, but each small-diameter log is deformed to some extent. Because of this, materials made from relatively hard wood species have a tendency to disintegrate due to elastic recovery. However, since the elastic recovery of wood occurs quite slowly, it is difficult to use adhesives that have sufficiently hardened. After molding.

In many cases, if the desired processing is carried out using a veneer lace, a slicer, a saw, etc., no particular problem will occur. In addition, if there is a problem, in order to make the wood plastic in the formwork,
The compressed state may be maintained for the necessary curing time, or the wood may be subjected to a wood softening treatment such as boiling, steaming, or microwave heating while being compressed and held using a mold or other holding member. Long-term shape stabilization can be achieved.

On the other hand, regarding the adhesive used in the present invention, it is common practice to select the adhesive and determine the bonding conditions depending on the moisture content of the small-diameter wood used, and in particular, the use of heat treatment such as boiling as described above In some cases, wet curing adhesives with high heat resistance are suitable. Furthermore, regarding the application of the adhesive, it is not necessarily necessary to apply it to all of the small diameter trees to be used, and it may be applied only to the adjacent small diameter trees. If it is not necessary to coat the entire outer circumferential surface of a small-diameter tree, coat only one portion. Of course, the same applies to the refill material.

In addition, the design of the formwork can be changed arbitrarily,
In addition to the batch type formwork as in the above embodiments.

Continuous molding meshes may also be used. For example, arrange a pair of rolls in a row, and gradually move from the first move to the bottom.
This method compresses small-diameter wood, and the large-diameter log 9, which is made into a desired shape with each pair of rolls, is roughly shaped into a predetermined shape as shown in FIG. Although the small-diameter trees 1 are formed, short pieces of each small-diameter tree 1 can be butted against each other if necessary. In such a case, you can apply adhesive to the butt part +01 and glue it.
There is a case where the butting points 1o are simply aligned to the butts, but in both cases it is better to shift the butting points 1o sequentially as shown in FIG. In addition, the tortoiseshell-shaped end pattern as shown in Figures 2 and 4 is
It has high commercial value, and in order to take advantage of the pattern, the end of the wood can be successively sliced thinly into decorative veneers and decorative boards.In this way, the large-diameter technology of the present invention creates new value. It is also something that creates.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 illustrate an embodiment of the method of the present invention, and both FIG. 1 and FIG. 2 show a cross-sectional view of a small diameter tree within a formwork. Cross section. FIG. 8 is a perspective view of the log having a larger diameter, and FIG. 4 is a cross-sectional view. In the figure, 1 is a small diameter tree, and '2 is a lower formwork. 8 is the upper formwork, 5 is the stopper, 9 is the log with a larger diameter,
10 is a butting point, and 11 is a gap. Patent applicant: Meinan Seisakusho Co., Ltd. 1 [-1 Figure 2 Procedural amendment (white sheet) October 20, 1981 1, Indication of case 1981 Patent Application No. 144202 2, Name of the invention 11. 94 ATs into the ball 8 Relationship with the case of the person making the amendment Patent applicant

Claims (1)

[Claims] A large number of small-diameter trees are bundled together in a predetermined formwork with the fibers in the same direction with adhesive applied to their outer circumferential surfaces, and the internal volume of the formwork is reduced to cause deformation of each small-diameter wood. A method for adhering and forming small-diameter trees, characterized in that the bonding area between the small-diameter trees is expanded, and this state is maintained at least until the curing of the adhesive is completed to bond and mold the small-diameter trees.