JPH0231646B2 - MOKUZAINOSOSEIKAKOSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for plastically working wood by heating it to 100° C. or higher under pressure.

A. Prior Art A technique has already been developed in which wet or water-saturated wood is heated and plasticized by irradiation with microwaves, and this technique is disclosed in Japanese Patent Laid-Open Publication No. 154106/1983. As described in this publication, the glass transition temperature of lignin, hemicellulose, and cellulose, which are the main components of wood, is approximately 130 to 250°C in a dry state, but 80°C in a wet state.
Drops to ~250℃. For this reason, conventional wood deformation methods involve heating the wood in a sufficiently wet state to plastically process it. However, in actual wood processing, no matter how moist the wood is and the wood is heated with microwaves, the wood is not plasticized enough to be easily plasticized. This is because when the temperature of wood exceeds 100°C, the moisture contained in the wood almost completely evaporates, resulting in an overdry state, which increases the glass transition temperature during deformation.

In order to sufficiently plasticize wood, it is necessary to heat the wood above its glass transition temperature while it contains moisture. However, no matter what heating method you use, water boils at 100°C under 1 atm, so it is theoretically impossible to heat wood to 100°C in a water-saturated state unless you heat it under pressure. It is.

If wood is heated in a pressurized sealed tank, it can be heated to over 100 degrees Celsius when saturated with water. However, the wood heated in this state undergoes plastic deformation, so if it is removed from the sealed tank and placed under atmospheric pressure, the moisture evaporates and the wood becomes over-dry.
Also, when the temperature of the wood drops to 100°C, it becomes plasticized and becomes difficult to deform.

The wood is sufficiently plasticized in a closed tank, but the device that deforms the wood inside a closed tank is a high-pressure tank that is larger.
In addition, the device itself becomes extremely complicated and expensive, and running costs also soar, making it completely impossible to put it into practical use.

B Structure and purpose of the present invention The present invention press-fits wood into a passage, closes the passage with the press-fitted wood, heats the wood in the closed state to heat the wood under pressure, and then closes the passage. The wood is press-fitted at the end to deform the wood.An important objective of the present invention is that the wood heated under pressure has a boiling point of water of 100℃ or higher, and the boiling point of water reaches 100℃ in a saturated state. To provide a plastic processing device for wood that can be heated to a high degree and easily deformed to a large extent without cracking.

Another important object of the present invention is to provide a wood plastic processing apparatus that can process wood continuously and efficiently in large quantities because the wood is plastically deformed at the end of the heating path.

C. Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings.

The apparatus for plasticizing wood using microwaves shown in FIG. A heating source for heating the wood 3 is provided.

The passage 1 is somewhat narrowed at the entrance and three places in the middle so that the wood 3 press-fitted therein is heated in a closed state. When the wood 3 is press-fitted into the passage 1, as shown in FIGS. 2 and 3, the wood 3 comes into close contact with the inner surface of the passage 1, and the passage 1 is closed.

Since the passage 1 is for heating and deforming the wood 3 under pressure, it is preferable that the entrance of the passage 1, the middle of the passage 1, and the vicinity of the exit be formed as shown in FIG. The pieces of wood 3 are tightly squeezed together.

However, it is also possible to narrow the passage 1 to two places, near the entrance and exit of the passage.

As shown in FIGS. 2 and 3, the cross-sectional shape of the passage 1 is determined to be rectangular when processing a square material, and circular, oval, or equiangular (not shown) when processing a round bar. .

The passage 1 is closed with a piece of wood 3 press-fitted therein, but cannot be completely hermetically sealed. This is because the wood 3 that blocks the passage 1 cannot completely prevent water vapor from penetrating it. The conditions under which water vapor passes through the wood vary depending on the type of wood, the ratio of the external size of the wood to the internal size of the passage, ie, how tightly the wood is pressed into the passage. Wood that is difficult for water vapor to pass through can be heated to a high temperature by pressurizing the inside of the passageway to a higher pressure. Wood, which allows little water vapor to pass through, is dense and requires strong force to resist deformation. Therefore, it is advantageous that this type of wood can be heated to a higher temperature because even hard wood can be easily deformed by heating.

It is very advantageous for the invention that some water vapor passes through the wood 3. this is,
This is because the moisture passing through the wood can remove the resin components within the wood. Wood whose resin components have been removed at the same time as the wood is deformed has the advantage of being able to be dried easily and quickly after molding, as well as reducing discoloration during heating.

To more effectively remove resin components from wood,
As shown in FIG.
A small amount of water or steam may be forced into the closed part of the container. The moisture forced into the passage 1 increases the pressure within the closed passage 1, passes through the wood 3, and is discharged from the exit or inlet side of the passage 1. When this water passes through the wood 3, it washes away the resin component contained inside the wood. Therefore, the greater the amount of water injected, the more resin components in the wood will be removed.

The pressure inside the passage 1 closed by the wood 3 is
It is dense and difficult for water vapor to pass through, so the wood 3 is rapidly heated in the passage 1, and the higher the amount of water injected, the higher the temperature.

As shown by the chain line in FIG. 1, if the entrance side of the passageway 1 is sealed with the opening/closing lid 9, the amount of moisture that passes through the wood 3 and leaks to the entrance side can be reduced. The opening/closing lid 9 is
When the wood 3 is guided to the entrance of the passage 1, it is opened, and when the wood 3 is press-fitted into the passage 1, the passage 1 is opened.
Close the entrance side. The rod of the cylinder 2 is slidably inserted into the opening/closing lid 9 in an airtight manner.

The end portion of the passageway 1 is formed from plasticized wood 3 into the desired shape. The end of the passage in FIG. 1 is curved to form the wood 3 into a curve. Passage 1 shown in Figure 4
The terminal end is formed to have a narrow cross section, and the wood 3 is compressed into a thin shape and processed into a fine piece.

As shown in FIG. 4, it is difficult for the wood 3 to be smoothly press-fitted into the end portion of the passage 1 through which the wood 3 is compression-molded. In this case, as shown in FIG. 5, it is preferable to clamp the wood 3 with rollers 10 and guide it to the end of the path. The roller 10 is rotationally driven by a motor or the like. Also, as shown in Fig. 6, three rollers 1
It is also possible to curve the wood 3 by clamping it at 0. Any one or all of these three rollers 10 are rotationally driven by a motor or the like.

In FIGS. 5 and 6, roller 10 is disposed within the passageway.

As the cylinder 2 for press-fitting the wood 3 into the passageway, any type of cylinder that can press-fit rod-shaped wood having the same cross-sectional shape one after another can be used.

The heat source consists of a heater 11 on the outer periphery of the passage and a microwave means 4 that irradiates microwaves to the wood inside the passage.

The microwave means 4 includes a high frequency power source 5 that oscillates microwaves of a required power, and a microwave passage 1.
It consists of a waveguide 6 that guides the waveguide 6, and a shielding member 7 that seals the exit of the waveguide 6.

As the high frequency power source 5, a magnetron with a high frequency output of several hundred watts to several kilowatts is used, which is the power necessary for heating wood. If one microwave means is insufficient in output, it is preferable to connect several stages of microwave means at predetermined intervals as shown in FIGS. 1 and 4.

The waveguide 6 is preferably connected at an angle with respect to the passage 1 so that there is no adverse effect due to reflection of radio waves shielded within the passage 1.

The shielding member 7 is made of, for example, a synthetic resin such as polyethylene or ceramic, which allows microwaves to pass through but not gases. This shielding member 7 prevents water vapor in the passage 1 from flowing into the waveguide 6, keeps the wood in the passage 1 airtight, and shields microwaves.

The heater 11 is fixed to the outer periphery of the passage 1 and heats the wood 3 from the outside via the passage 1. In this way, the device in which the wood 3 in the passage 1 is heated from the outer periphery of the passage by the heater 11 and from the inside by microwaves has the advantage of being able to uniformly heat the entire wood 3.

As the heater 11, a nichrome wire heater heated by electricity, a heat exchange heater pipe through which high-temperature steam or combustion gas is passed, or the like can be used.

Also, although not shown, the wood to be press-fitted into the passage,
It is also possible to preheat the material in advance, for example, by immersing it in hot water or by spraying it with steam.

D Conditions of Use The wood plastic processing apparatus configured as described above is
Wood 3 is press-fitted into the passage 1 one after another using the cylinder 2. The wood 3 itself closes the opening of the passage 1 at the narrowed point of the passage 1. In this state, the wood 3 is heated, some of the water contained in the wood evaporates, the pressure inside the passage 1 is increased, and the wood 3 is heated.
is heated under pressure to be sufficiently plasticized. The plasticized wood 3 is fed into the end of the passage 1 and shaped into the desired shape, such as by bending or compressing.

E Effects The wood plastic processing apparatus of the present invention is configured so that the passage into which wood is continuously press-fitted is closed by the wood itself, and the wood in the closed state is heated. For this purpose, the wood is heated under pressure and plasticized to a state where it is easily deformed, and this wood is further press-fitted into the end of the passage and formed into the desired shape. For this reason, just by press-fitting the wood into the passage, the wood can be easily and reliably removed.
In addition, the wood can be deformed significantly with minimal cracking, and the processing efficiency is high, allowing a large amount of wood to be processed in a short period of time, making it possible to achieve truly ideal wood processing.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of a wood plastic processing apparatus showing one embodiment of the present invention, and FIGS.
- line sectional view and - line sectional view of figure 4
The figure is a schematic sectional view of a wood plastic processing apparatus showing another embodiment, and FIGS. 5 and 6 are sectional views showing the end portion of the passage. 1... Passage, 2... Cylinder, 3... Wood, 4
...Microwave means, 5...High frequency power supply, 6...
Waveguide, 7... Shielding member, 8... Water injection means, 9...
...Opening/closing lid, 10...Roller, 11...Heater.

Claims (1)

[Claims] 1. A wood processing device that heats and plasticizes wood, which includes a passage into which a rod-shaped piece of wood having a constant cross-sectional shape in the longitudinal direction is inserted, and a piece of wood that is press-fitted into the passage. and a heating source for heating the wood in the passage, the passage of wood having at least two
The passage is formed in a cross-sectional shape that is closed by the wood that is press-fitted here, and the end is formed in a shape that deforms the wood into the desired shape. It closes a part of the passage by itself, and the heating source heats the wood in the closed state and the moisture contained in the wood, and the wood is heated under pressure by the generated water vapor, and the boiling point of water is raised under pressure. The temperature rises to over 100℃,
A wood plastic processing apparatus characterized in that the wood is press-fitted into the end of the passage in this state and deformed into a desired shape. 2. The wood plastic processing apparatus according to claim 1, wherein the heating source includes microwave means for irradiating the wood with microwaves. 3. The wood plastic processing apparatus according to claim 1, wherein the end of the passage is curved and the wood is curved. 4. The wood plastic processing apparatus according to claim 1, wherein the end of the passage is narrowed and the wood is compressed and shaped.