JPS646003B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing hollow synthetic square timbers used for buildings etc. from a plurality of materials obtained by dividing logs into fan-shaped cross sections.

By the way, when this type of square lumber is manufactured from raw wood, the peripheral part of the raw lumber 1 is removed at four planes to form a square lumber 2 with a rectangular or square cross-sectional shape, as shown in Fig. 1. This manufacturing method is extremely uneconomical as a considerable amount of waste wood3, 3... is generated in four places around the log, and this is one of the reasons for the soaring price of this type of square lumber. Such a single piece of square lumber is easily distorted, and therefore, when used in a building, it causes problems such as deformation of the entire building over a long period of time.

The present invention was made in view of the above circumstances, and consists of dividing raw wood radially to form a large number of fan-shaped cross-section members, and removing the center and arcuate portions of each member to form parts from one side of the fan shape. forming a pentagonal cross-sectional material with the same cross-sectional shape, consisting of a bottom surface, an upper surface parallel to the bottom surface, two side surfaces perpendicular to the bottom surface consisting of one fan-shaped side, and a slope consisting of the other side of the fan-shaped shape,
By joining four pieces of this material together, a hollow synthetic square lumber can be obtained. This reduces the amount of waste wood produced during sawing as much as possible, and by making the square lumber hollow, it is possible to make effective use of logs. In this way, it is possible to reduce the price of the square timber, and to provide a square timber that is lightweight and has little distortion.

An _example of the manufacturing method of _the present invention will be described below. _First , as shown in _FIG . , eight members 11, 11, . Next, for each member, as shown in FIG.
The intersection of the corners 12, the center part 13 of the sector by the plane z perpendicular to the side a, and the plane w perpendicular to the side a.
By deleting the circular arc portions 14, the bottom surface A formed by the side a, the top surface B parallel to this, and the center side and outer side surfaces C and D perpendicular to the bottom surface A are obtained.
In addition, a material 15 having a pentagonal cross section is formed by a slope E formed by side b between the side surface C on the center side and the top surface B. After that, using four pieces of this material 15, the fourth
As shown in the figure, the side surface C on the center side of each material,
C so that the bottom surfaces A and A match, and the top surface B,
By joining B so that the outer side surfaces D and D coincide with each other, a square material 17 with a rectangular external cross section is produced, with a hollow part 16 formed in the center by slopes E, E, etc. made of sides b of each material. It will be done. Here, each material may be joined using a dowel 18 as shown in the figure, but it may also be joined using an adhesive, or a combination of a dowel and an adhesive may be used.

However, the square timber 17 manufactured in this way is
Figures 1 and 2 to 4 match the diameters of logs on the drawings.
As is clear from comparing the figures, the external dimensions are only slightly smaller than the conventional single square timber 2, and since two square timbers are obtained from one log, the yield is almost doubled. The result will be similar to that of a nearby improvement.

Next, another embodiment will be described. In the embodiment shown in FIG.
By equally dividing x' ₁ to x' ₆ , 12 members 21, 21, etc., each having a sector-shaped cross-sectional shape with a central angle of 30° are obtained, and each member is flat as in the previous embodiment.
Corner part 22, center part 23, arc part 24 at y', z', w'
is removed to form a material 25 with a pentagonal cross section, and four of the materials are used to form a hollow square timber. According to this embodiment, three square timbers can be obtained from one log. It will be done. In addition, FIG. 6 shows a material 3 with a pentagonal cross-section having a different cross-sectional shape from one member 31 with a fan-shaped cross-section obtained by dividing raw wood radially.
5, 35', etc., and by joining four pieces of the same size, an even larger number of square pieces can be obtained. Note that the corner portion 12 and center portion 1 that are deleted due to the planes y and z in FIG.
The corner portions 22, center portion 23, etc. that are removed by the planes y' and z' in FIGS. 3 and 5 can also be used as small-sized square pieces by forming the cross section into a pentagon. In addition, as shown by the chain line in FIG.
9 may be attached to make the square timber look like a real square timber. Furthermore, when dividing the log radially, it is not necessary to divide the log 40 equally on a plane passing through the diameter as shown in FIG. For example, it may be divided into four equal parts to form a member 41 with a central angle of 45 degrees, and the other half may be divided into eight equal parts to form a member 41' with a central angle of 22.5 degrees.

Since the method for manufacturing the synthetic square timber of the present invention has the above-described configuration, the raw wood is effectively used and the yield is significantly improved, thereby making it possible to reduce the price of this type of square timber, and also making it possible to produce the synthetic square timber according to the present invention. Because the square timbers are synthetic and have hollow parts, they are lightweight and have little distortion.
This has the effect that square timber suitable for construction, furniture, etc. can be provided at low cost.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the conventional method for manufacturing square timbers;
Fig. 2 is an explanatory diagram of the process of obtaining a plurality of members from logs in one embodiment of the present invention, Fig. 3 is an explanatory diagram of the process of obtaining a material with a pentagonal cross section from each member, and Fig. 4 is an explanatory diagram of the process of obtaining a material with a pentagonal cross section from each member. FIGS. 5, 6, and 7 are explanatory diagrams of the process of obtaining a square timber from a raw material, respectively, of other embodiments. 10, 20, 40 are logs, 11, 21, 31 are parts, 15, 25, 35, 35', 35'' are materials,
A is the bottom surface, B is the top surface, C is the center side, D is the outer side, E is the slope, 17 is the square timber, a...one side of the fan shape, b...the other side of the fan shape.

Claims (1)

[Claims] 1 Divide the log radially along a plane passing through the diameter or radius to form a plurality of members with a fan-shaped cross section, and for each member, a bottom surface consisting of one fan-shaped side,
A pentagonal cross-section having a slope formed by a top surface cut in a plane parallel to the bottom surface, two side surfaces cut in a plane perpendicular to the bottom surface, and the other fan-shaped side left between the center-side side surface and the top surface. One or more pieces of material with the same shape are formed, and then this material 4 with the same cross-sectional shape is formed.
Using a book, join the upper surface of each material and the side surface on the center side as well as the side surface on the center side with adhesive or thick rod or both, respectively, so that a hollow part is formed on the slope. A method for manufacturing a hollow synthetic square timber characterized by: