JPS643641B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the effective use of logs having a relatively small diameter, such as wood from thinning in afforestation.

As shown in Figure 1, for example, Motoguchi
If the log 1 has a diameter of about 10 cm and the length 2 is about 3 m, the diameter of the end 3 will be about 1/2 that of the main end, or about 5 cm. Items of this size are of limited use even if they are made into square timbers. There is no way that it can be used as a structural member like a pillar material. Even if you were to finish it into a shape similar to a board, there is nothing you can do if the end is 5cm long. The largest square that can be finished within a circle with a diameter of 5 cm is 3.4 cm on each side, but from logs of this size, 3.4 cm
If only one piece of square lumber is finished, the efficiency with which the remaining scraps are harvested is too low, and it is not a problem at all from the standpoint of profitability. In short, if we are to consider the effective use of such small-diameter logs, the question is how to make the ratio between the finished material and the remaining offcuts efficient.
In other words, it is necessary to consider finishing methods that minimize the amount of waste and maximize the amount of use.

In recent years, forestry projects in mountain forests have been planting trees too densely to prevent losses due to dieback, snow breakage, etc. From 10 years ago, when tree planting was particularly encouraged, to today, small-diameter trees like those mentioned above have grown to a diameter of around 10 cm, but when it comes to the ``mabiki'' or thinning period. If this is not applied, the trees that should be growing will stop growing, which is not good. In general, this type of dense planting will continue forever, but this thinning work is not an easy task, and in order to allow some trees to grow, the remaining trees must be cut and thrown away. Therefore, there is no other way than that it is a completely backward-looking work. Even if you spend money on labor for something like this, it won't immediately lead to profits;
Rather, it is a property that is added to the selling price of wood that will grow and be harvested at a later date, and people involved in afforestation projects want to keep this cost to a minimum and, if possible, think of ways to use it profitably. This is my long-cherished wish.

Thus, in the past, no method of utilizing small-diameter trees had been developed, and unprofitable thinning operations had to be carried out.

This invention aims to effectively utilize small-diameter trees cut from such mountains by finishing them as they are so that the end portions are reduced as much as possible, and to utilize them as structural members for buildings or other construction members. be.

The embodiments will be described below with reference to the drawings.

That is, as shown in Fig. 2, one side has a length l
If you were to make it by combining small-diameter square timbers, the end side would be finished to form a square 6 with each side 3.4 cm
A deformed pyramid M with a diameter of 10 cm and finished in a deformed pentagon 8 with the outer part 7 at a right angle is made, and opposing members are arranged in the same direction on the cross-sectional diagonal line of the large square piece V, and the opposite members are arranged on the opposite line. When the members are arranged facing each other in opposite directions, that is, the end side and the base side are arranged alternately, a large square piece V with one side a is formed.
is completed. If the contact surfaces of each member arranged in this manner are bonded with an adhesive or the like, it can be used as a structural member without any worries.

Now, in order to observe it more closely, let's look at the external shape of the deformed pyramid M in the above example.
As shown in FIG. 3, a deformed pentagon 9 on the mouth side,
It is connected to the square 10 on the end side by a plane, and its intermediate cross section has an approximate shape with the deformed pentagon 9 on the source side, that is, one side of the deformed pentagon 9 gradually reduces and converges to one corner of the square 10. The shape is the same as the deformed pyramid M placed opposite to the same figure.
If the outer edge lines 11 and 11' are parallel and symmetrically arranged between M' and M', the two will be in contact at the base side, but will become more open toward the distal side. Become. However, members arranged on the opposite side are exactly the opposite. That is, as shown in FIG. 4, the closer it is to the front, the more it opens. Therefore, if the four members were gathered together and only the parts that were in contact were glued together, a strange gap would be created in the center. That is, as shown in FIG. 5, four long isosceles triangular surfaces 12, 13,
A tetrahedron N surrounded by 14 and 15 is formed. The length of this tetrahedron is 3 m if the length of the completed large square material V is 3 m, and the length f of the end edge is the same as that of the deformed pentagon on the front end side shown in Figure 4. It is equal to the length of contact between comrades.

In this way, when the four deformed pyramids M are arranged so that the end side and the base side are alternated, and their contact parts are bonded with adhesive, the part that hits the center core Although a void having the shape shown in FIG. 5 is created, the effect on the structural strength of the large square timber itself is not significant. In short, it is the outer portion that greatly influences the moment of inertia of area. If the neutral axis is located at the center, the effect increases as the cube of the distance approaches the outside, so the space near the center has little to do with it.

However, when actually using the
It doesn't look very good if there are voids inside when digging, so you can fill these spaces with a filler like Styrofoam. Alternatively, a shaped member made of wood or polymeric chemical material that has been processed into the same shape as the tetrahedron N may be produced in advance, and the shaped member may be pasted together with the shaped member stuffed inside. In short, it is sufficient to consider filling this void portion with another member in some way.

Regarding the physical properties of the filler, it is preferable that the properties resemble those of wood as closely as possible. They must also be easy to adhere to each other. Once these conditions are met, the cheaper the better.

The above is an example in which the large square material obtained by gluing the deformed pyramids M in the above-mentioned arrangement is considered to have a square cross section like a column or a rectangle close to it, but it is also possible to create a square material with an even larger cross section. When the need arises, it is necessary to arrange and bond a large number of adjacent members so that the starting and distal sides are alternated and the slopes of adjacent members are in contact with each other as described above. There is. That is, as shown in Fig. 6a, the starting side is an octagon 16 and the end side is a square 17, and if one side of the octagon 16 touches each square 17 as shown in the figure, this surface will be The opposite side, that is, the other side, is just the opposite combination. However, if you look carefully, you will see that on the other side of the diagonal line 18 where the octagons 16 meet each other, a void similar to the void in the tetrahedron shown in FIG. 5 mentioned above is formed. .
There will be no particular problem in this case, considering that it is filled with the above-mentioned filler. Tazu,
When finishing a large square piece, it is undesirable to cut across the diagonal line 18, and if this part is cut, the filler material will appear on the surface. As long as the other parts are cut to create a rectangular piece, there will be no particular problem. If you pay attention to this point, it will theoretically be possible to manufacture any large square timber. Figure 6b
exemplifies a combination in which the base side is hexagonal and the distal side is triangular. In this case as well, the process of filling the gap formed with the filler is the same as described above, so the explanation will be omitted.

Next, an example will be described in which voids are completely eliminated by simply adhering without using any filler.

When making a large square piece like the one shown in Fig. 2, make four deformable members P of the same shape as shown in Fig. 7 and combine them in an arrangement such that adjacent members face in opposite directions as described above. View. The deformable member P shown in FIG.
9 and an isosceles triangular plane 20 cut as the base of the diagonal line 19 are finished parallel to the right-angled edge line 21 on the opposite side. The vertex 22 of this plane 20 is placed at the center point of this member. That is, when the member P is erected, the plane 20 is a vertical plane up to the center of the member, so when the four members are put together, all the surfaces come into contact and no gap is created. In order to understand this relationship, in Figure 8, the main end side is shown in a, the central section is shown in b, and the end side is shown in c. Since the diameter decreases proportionally, The side diameter is 10 cm, the center is 7.5 cm, and the distal end is 5 cm, so each cross section must be formed within them. 8th
When the cross sections indicated by a, b, and c are superimposed on each other, the result is as shown in FIG. 9.

In this way, by dividing the gap created in the center of a large square piece into four equal parts and having each member absorb and form each equally divided gap, a complete member can be created just by gluing it together. It is completed, but
In this method, the processing required for finishing is slightly more difficult than in the previous embodiment. This is because a separate step of finishing the plane of the above-mentioned isosceles triangle is added.

All of the methods for processing each component described here generally utilize woodworking machines. For example, each side is cut with a bandsaw or circular saw and then finished with a planer. Make a ruler that matches the angle and slope of each surface,
By moving the member along it, it is sufficient to be able to finish it in that way. All such processing and finishing should be suitable for assembly line operations, and the equipment in the factory should be arranged so that they can be carried out continuously.

As for the adhesive, a thermoplastic adhesive may be used, but since it begins to melt at 150 to 170°C, a thermosetting adhesive such as an epoxy adhesive is preferable. Adhesives have developed tremendously recently, so they are easy to handle.
You should consider using something that does not separate once it is glued, is resistant to heat, and is inexpensive.

The method of eliminating internal voids can be applied as is to the shape shown in FIG. 6a for cutting out the above-mentioned large square timber. The void formed on the other side of the diagonal line 18 in the figure is divided into four equal parts as described in the above embodiment, and each of the four equal parts is finished in a shape that allows it to be absorbed into an adjacent member. If this is done, this void will be completely eliminated. At that time, the cross sections of both ends and the center are shown in Figure 10a,
It becomes like b, c. That is, a indicates the opening side, b indicates the center, and c indicates the distal side. The diameter also decreases proportionately, and it fits inside the log.

Various arrangements can be considered using this principle, but it is best to have the proximal end in a hexagonal or octagonal shape, and the distal end in a triangular or quadrangular shape. Doing so is not a good idea as it will make finishing difficult. On the starting side and the ending side,
If the starting side becomes a polygon that is twice the size of the ending side, they should be combined well. However, it goes without saying that this invention is not limited to this.

As described above, this invention involves arranging adjacent members alternately, finishing each member in the shape of a polygonal pyramid, and filling the gaps between them with another filler.
Alternatively, divide the gap into equal parts according to the number of members in contact with the gap, and use a finish that absorbs the shape of the equally divided gaps with respect to the adjacent members, or use either method to create solid square timbers. It is a synthetic wood whose contact surfaces between each member are bonded with adhesive, and it is an economical structure that makes effective use of small-diameter wood by taking advantage of the difference between the head and end. This has effects such as being able to obtain members.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the shape of a small-diameter log. FIG. 2 is a perspective view showing the construction of a large square piece with a rectangular cross section and an internal void. FIG. 3 is a perspective view showing the arrangement of two opposing members. FIG. 4 is a perspective view similarly showing the arrangement of opposite direction members. FIG. 5 is a perspective view showing the shape of the cavity. FIGS. 6a and 6b are plan views showing the arrangement of one side when multiplexed to obtain a large square piece. FIG. 7 is a perspective view showing the shape of each member when the internal voids of the large square timber are absorbed by each member.
FIG. 8 is a cross-sectional view showing the cross-sectional shapes of both sides and the center of the member in FIG. 7. FIG. 9 is an explanatory sectional view when the respective cross sections shown in FIG. 8 are combined. FIG. 10 is a sectional view showing the cross sections of both sides and the center when internal voids are absorbed by each member when a large square timber is obtained using multiplexed members. The codes and names of the main parts are 1... Motoguchi, 3...
End, 8... deformed pentagon, M, M'... deformed pyramid, V... large square piece, N... tetrahedron, P... deformed member, etc.

Claims (1)

[Scope of Claims] 1. The same member having a polygonal pyramid shape or a shape similar to the polygonal pyramid with different numbers of angles at the end and the base is arranged with the end and base sides alternated, and A synthetic timber made by effectively utilizing small-diameter wood, characterized in that two or more inclined surfaces of a member are glued together to form a large square timber. 2. The slope where one side is the side where the Motoguchi comrades are in contact is
A synthetic wood made of effective use of small diameter wood according to claim 1, wherein the members are bonded to each other in a vertical plane up to the center. 3. A synthetic wood made of effective use of small-diameter wood according to claim 1, wherein a filler is filled in an internal void surrounded by an inclined surface whose sides are the sides where the two ends touch or the opposite sides. 4. The same member in the shape of a polygonal pyramid or a similar shape with different numbers of angles at the end and the base, so that the end and base sides are alternate, and two or more sides of the member are sloped. Manufacture of synthetic wood by effective use of small-diameter wood, characterized by cutting out square timbers or boards of a desired size or shape from large square timbers obtained by arranging a large number of square timbers so that their surfaces contact each other and gluing the contacting surfaces. Law. 5. A method for producing synthetic wood by effectively utilizing small-diameter wood according to claim 4, wherein a sloped surface having one side where the base ends are in contact with each other is a mutually perpendicular contact surface up to the vicinity of the center of the member.