JPS60257203A - Method of preventing strain of 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 straightening sawn wood, and in particular, the present invention relates to a method for straightening sawn wood, and in particular, the invention aims to prevent distortion caused by moisture contained inside the wood and changes in the environment such as temperature and humidity. This invention relates to a method for preventing distortion.

In general, the cell density of wood varies depending on the state of the tree, sunlight, shade, and location conditions, and the moisture content and density also vary depending on the type of wood.

Therefore, if these woods are simply sawn, as the wood dries, as shown in Figure 1, due to the relationship between the rough density of the cells, moisture content, temperature, etc., the wood may become curved, warped, or twisted, or - as shown in Figure 1. However, due to deformation such as the formation of cracks, the value of the wood product decreases, and in extreme cases, there is no longer any usable parts and the wood becomes waste.

Until now, it has not been possible to use sawn wood as is, so most of the wood, excluding core materials, has been left to dry naturally for a certain period of time to reduce the moisture content. Currently, products are made by cutting or pressing after lowering the material and subjecting it to a predetermined deformation.

However, even in wood products, the cell density of the wood is subject to distortion due to the outside air, temperature, humidity, and other environmental conditions, and it takes 3 to 10 years for this distortion to almost completely disappear, depending on the type of wood. Therefore, as shown in Figure 2, for pillar materials such as logs and square timbers that are prone to cracking, grooves have been formed from the beginning, called back splitting, from the center. There is. However, since drying progresses gradually from the outside of the wood, there are drawbacks such as shrinkage and cracking on the outside compared to the inside, which is a problem in the industry.

This invention was made in view of the above-mentioned circumstances, and involves irradiating products such as sawn logs, square timbers, and boards with high-frequency waves for a predetermined period of time to heat the interior of the wood to a predetermined temperature, thereby causing distortion. By applying measures such as pressing on the wood and letting it cool down to normal temperature and dry naturally,
The present invention provides a method for preventing distortion of wood by causing internal hardening from the core of the wood, thereby making effective use of the wood and increasing its commercial value.

Embodiments of the present invention will be described in detail below with reference to the drawings.

First of all, in wood, moisture and molecules of glue-like materials such as cellulose are contained between the wood structures consisting of xylem fibers, tracheids, and ducts, and these are dried from near the outer surface. Deformed cracks occur over time due to wood dissipating and moving into the air, and with conventional natural drying, it takes several years to fully dry the internal composition of the wood structure. It is something that

Therefore, this method was developed based on the idea that distortion over time can be prevented by causing internal hardening in advance from the central direction of the wood structure and hardening and bonding the glue-like material components. Products such as sawn raw wood logs, square timbers, and board materials are irradiated with high frequency waves to raise the temperature inside the timber to around 90°C, thereby heating the paste-like material and hardening and bonding it.

At this time, the wood, which tends to warp and deform, is pressed using a simple device and heated for a certain period of time, then allowed to cool to normal temperature, and then left to air dry for a short period of time to create the product. climb.

Next, experimental examples conducted based on the process according to the present invention will be explained.

First, paulownia wood is 10 m thick, 520 m wide, and 9 long.
A 50-inch plate material to be treated was used as a test material. The material to be treated has a moisture content of 15 cm, and as shown in Fig. 3, the output of the high frequency generator was 12 KW, and after irradiation for 3 minutes, the high frequency generation and output of the device were stopped, and - The product was made into a product by cooling it day and night.

The paulownia wood obtained through the above process has no difference in appearance from normal paulownia wood, and there is no change in color or feel.
There was no distortion or change even if it was left in a high temperature place.

Furthermore, a zelkova material to be treated with a thickness of 20!1 m, a width of 5005 m, and a length of 4000 m was used as a test material. As a treatment, irradiation is performed from above and below for about 30 minutes at the above output, and the internal temperature of the treated material is 90° to 95°, and the external temperature is 40° to 4.
The temperature reached 5°. After that, it takes about 10 days for this treated material to completely solidify. The resulting zelkova wood had the same appearance, color and feel as paulownia wood.

There was no distortion or change even when left in a high temperature location.

In addition, in the method for preventing distortion of wood according to the present invention, when the material to be treated is irradiated with high frequency waves, it is also possible to create a special atmosphere such as a vacuum state, and in this case, the internal composition of the material Since moisture and glue-like material move and harden at around 40° C., there is no need to raise the temperature to high temperatures, making it possible to lower the output of the high-frequency generator and shorten the irradiation time.

As explained in detail above, the method for preventing distortion of wood according to the present invention does not require costly equipment unlike the conventional example, and can be used with a simple device at low cost.
The utility value of wood can be increased.

In addition, the wood treated by the method of this invention has its interior hardened and bonded without causing any change to the wood surface, and retains atmospheric respiration on the wood surface.
Distortion of the wood is prevented without affecting the interior.

Furthermore, the method according to the present invention differs depending on the type and size of each piece of wood, and can be applied to all types of wood by appropriately setting the output of the high-frequency generator, time, irradiation direction, etc., and can greatly increase the utility value of wood. It has effects such as being able to improve performance.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a modified example of wood, FIG. 2 is an explanatory diagram of a split groove state showing a conventional embodiment, and FIG. 5 is an explanatory diagram of a high frequency irradiation method showing an embodiment according to the present invention. Patent applicant Sato Kirizaiten Co., Ltd. Figure 2 Figure 3

Claims (1)

[Claims] In the straightening method for sawn wood, high frequency waves are irradiated to the wood to be treated for a predetermined period of time to heat the inside of the wood, harden and bond the glue inside the wood, and then leave to cool to normal temperature. A method for preventing distortion of wood.