JPH0397503A - Lumber treating method - Google Patents

Abstract

PURPOSE:To increase mechanical strength while keeping a grain as original in a simple work-treatment by making lumbers absorb, after that, softening them through high frequency dielectric heating and then pressing them. CONSTITUTION:After lumbers are made to absorb water, they are swelled by high frequency dielectric heating and pressed thereafter. The kind of lumbers used in the treatment is not limited particularly, however, it is preferred to employ a soft-low density material such as cedar or cedar from thinning because they are easily to be treated by this method. At first, lumbers are steeped into water and made to absorb water. Although the amount of water absorption is not limited in particular, it is preferable that the water-absorb part has a fiber saturated point (the percentage of water content is about 28% ; abbreviate as F S P hereinafter) or higher. The heating is conducted by high fequency dielectric heating. It is generally carried out by micro-wave heating among methods of high frequency dielectric heating. The conditions of pressing are not particularly limited but it is sufficient that the pressure is of the order of 20 - 30 kg/cm<2> or more, and the lumber can be compressed approximately one fourth as compared with its original dimensions.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a processing method for expanding the range of uses of wood.

[Conventional technology]

Currently, thinned cedar wood is left unused or discarded without being used effectively. This is because soft, low-density materials such as cedar have a limited range of uses. Therefore, in order to increase the density of soft low-density materials such as cedar wood and expand its range of use, the wood is first crushed into mJll shapes, mixed with an appropriate adhesive, etc., and then heated and compressed to give it an impressive shape. It is common to use it as a fiberboard or particle board obtained by doing this.

[Problem to be solved by the invention]

However, when processed into 77 Ibarboard or particle board, etc., there is a problem that the processing process becomes complicated and the processing cost increases, and the appearance of the grain that is unique to wood is lost, so it is difficult to use it. There was also the problem that the scope would be limited. The present invention has been made in view of the above points, and an object of the present invention is to provide a method for processing wood that can expand the range of uses of wood by using simple processing and making use of the wood grain as it is. It is something.

[Means to solve the problem]

The first method of treating wood according to the present invention is characterized in that after the wood absorbs water, it is heated with high-frequency electricity to swell, and then pressurized. The second method is characterized by making the wood that has been treated and pressurized absorb water, and then subjecting it to high-frequency dielectric heating to cause it to swell. The present invention will be explained in detail below. The species of wood used for the treatment is not particularly limited, but soft low-density materials such as cedar wood and thinned cedar wood are preferred because they can be easily treated according to the present invention. First, the wood is soaked in water to absorb water. Although the amount of water absorption is not particularly limited,
The area where water is absorbed is the fiber saturation point (water content approximately 28%; hereinafter F
(abbreviated as SP) or more, it is preferable that the water content be saturated with water. Next, this water-absorbed wood is heated. Heating softens the parts of the wood that have absorbed water. This heating is performed by high-frequency electronic heating. Wood is a poor conductor of heat, so if you heat it from the outside, it will take time to reach a uniform high temperature inside, but with high-frequency dielectric heating, you can heat the wood evenly from the inside. This allows the wood to be heated quickly and evenly. Among high-frequency dielectric heating methods, micro dielectric heating is commonly used. Microwave heating conditions vary depending on the TH type, volume, moisture content of the wood, frequency and output of the microwave, etc.
It is preferable to set conditions so that the wood can be heated to 100°C or higher. When wood is heated rapidly using microwave heating in this way, the water contained in the wood is rapidly heated, increasing the pressure inside the wood and causing moisture to move through the wood. The location can be made flexible. After softening the wood in this way, when the wood is pressurized, the softened wood is easily compressed and becomes denser. The conditions for pressurization are not particularly limited, but a pressure of about 20 to 30 kg/am” or higher is sufficient, and the wood can be compressed to about 174 mm of its original size. The time of pressure is not particularly limited, but it is necessary to maintain pressure until the moisture content of the wood is about 15% or less.In this way, by increasing the density of wood, the mechanical It increases the strength and can expand the range of uses, especially in soft low-density materials such as cedar wood and cedar cutting wood. It is also possible to deform the wood by bending it. Using the wood that has been densified by the first method according to the present invention as described above, it is possible to perform the second method. In other words, first, this densified wood is immersed in water to absorb water.The amount of water absorbed is not particularly limited, but as with the first method, it is preferable to make it equal to or higher than FSP. When wood is heated with microwaves, the water contained in the wood is rapidly heated, increasing the pressure inside the wood, causing the compressed and densified wood to swell and return to its original shape and dimensions. Generally, it can be restored to about 85 to 95% of its original dimensions. *If the wood is bent by applying pressure, it will be restored to its original state. The wave heating conditions are not limited either, but may be set to the same degree as in the first method.After the first method has been performed and the wood has been compressed, the second method is applied. Because it is possible to restore the original state by processing the method, by combining the processing of the first method and the processing of the second method, the properties of shape memory wood, such as shape memory alloy, can be restored. By using this, it becomes possible to process wood for various purposes.

【Example】

The present invention will be specifically explained below using examples. A cedar wood with a size of 6cm x 30e and a thickness of 2e is immersed in water and absorbed until the water content reaches FSP or higher, and then heated using a home microwave oven with a frequency of 2450MHz and an output of 600W. Microheated for 1 minute. Next, this cedar material was compressed at a pressure of 20 kg/a1 for 3 hours until the temperature of the cedar material cooled to room temperature, thereby compressing the thickness of the cedar material from 2C-1 to 1C-1. Densified. "Cold 11" - The cedar wood that was made highly dense in Example 1 was immersed in water to absorb water until the water content reached FSP or higher, and this was carried out at a frequency of 2450M.
Microheated for 2 minutes using a household microwave oven with an output of 600 W and Hz. By heating with microwaves in this way, the cedar wood expands, and the thickness increases from the IC ring to 1.9cm.
It was restored to . X-hen 1'11a = 30cm, width b = 6cm, thickness c = 2cm
5c++ from the end as shown in Figure 1.
Concave portions 2 were cut out on both sides of the + point, and a portion 5 cq from this end was flooded with water until the water content in this portion reached FSP or higher (water absorption points are shown in Figure 1 (a)). (Illustrated with diagonal lines). Next, the parts of this cedar wood 1 other than the four areas where the water had been absorbed were wrapped in aluminum foil, and heated in a household microwave oven with a frequency of 2450 MHz and an output of 600 W for 1 minute. Immediately after this, the above-mentioned area where water was absorbed and heated was compressed by applying a pressure of 20 kg/am2 as shown by the arrow in Fig. 2(a) (the compressed area 3 is shown as dots). Next, we cut the round bar including the compressed parts as shown in Figure 3.
A round bar part 4 and a fletching part 5 at the rear end are shaped. On the other hand, a heart plate 7 with a hole 6 in the center and a heart-shaped outer shape was made using another cedar material, and the holes 6 of the heart plate 7 were inserted into the nine-bar part 4 as shown in FIG. was inserted into the Then, the compressed part 3 is immersed in water to absorb water until the water content in this area reaches FSP or higher (the water absorption area is shown with diagonal lines in Figure 4 (.)), and after removing this water absorption area and wrapping it in aluminum foil, By placing it in a household microwave oven and heating it in the microwave for 1 minute, the compressed part was expanded and restored as shown in Figure 5. Finally, by cutting this swollen part into an arrowhead shape, you can create a mochichu that looks like an arrow shot through a heart, as shown in Figure 6. In this item, both the arrowhead part 8 and the arrow feather part 5 are larger than the diameter of the hole 6 in the heart plate 7, so it is unclear from the appearance how they were passed through the heart @ 7, and it is sold as a mysterious toy. can do. In this way, by combining the processing of the first method and the processing of the second method, it is possible to make such toys, but of course it is also possible to make other crafts, practical furniture, etc. It can also be applied to manufacturing.

【Effect of the invention】

As mentioned above, in the present invention, after the wood absorbs water, it is softened by high-frequency dielectric heating, and then pressurized, so that the wood can be made high with only the steps of water absorption, high-frequency groove electric heating, and pressurization. It can be densified, and since it is only compressed by applying pressure, the wood grain of the wood can be preserved as it is for its appearance. It is possible to expand the In addition, since the first method was used to make the compressed wood absorb water and then subjected to high-frequency dielectric heating to cause it to swell, the second method was used to return the compressed wood to its original state. By combining the first method and the second method, it is possible to process wood for various purposes.

[Brief explanation of drawings]

Figures 1 to 5 show each step of an embodiment of the process according to the present invention, in which (.) in each figure is a front view, (b) is a side view, and Figure 6 is the process obtained by the same process. FIG. 2 is a perspective view of the toy. 1 is the cedar wood and 3 is the compressed part.

Claims (2)

[Claims] (1) A method for treating wood, which comprises making the wood absorb water, softening it by high-frequency dielectric heating, and then applying pressure. (2) A method for treating wood according to claim 1, which comprises making the pressurized wood absorb water and then subjecting it to high-frequency dielectric heating to cause it to swell.