JP2891910B2 - Wood molding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming wood, and more particularly to a method for compressing soft coniferous wood such as cedar and larch to produce a prism and a cylinder having a high surface hardness and a well-formed shape. The present invention relates to a method for manufacturing a semiconductor device.

[0002]

2. Description of the Related Art In order to improve the physical properties of soft wood such as cedar, there is known a method of compressing wood softened by means of wet heat treatment in the radial direction. This method is called consolidation, and there is also an example of applying this consolidation to compress a cedar log to produce a prism. According to Japanese Patent Application Laid-Open No. 3-295605, a cedar log is heated and softened and compressed by a mold to form a polygonal cross-sectional shape, and then the shape is fixed by drying or cooling and reheating. According to Japanese Patent Application Laid-Open No. Hei 3-231802, Japanese cedar wood is heated and softened in saturated steam at 5 to 25 atm, compressed between a pair of molds and formed into a polygonal cross section. And heat it at about 180 ° C. to fix the shape. In any case, the formed prism has the advantage that the surface hardness is higher than that of the cedar logs obtained by cutting, and no cutting chips are generated during processing.

[0003] However, in the above method, when heat-softened wood is loaded into a mold and compressed, if the wood is taken out of the mold immediately after the compression is completed, the wood is reduced in volume and expanded to the desired consolidation. There was a problem that conversion was difficult. To avoid this volume relaxation, for example, a method in which cooling water is circulated through the mold while holding the compressed wood in the mold, and the wood is taken out of the mold after the temperature of the wood has reached the softening point or lower, There is a method in which the temperature is raised while the compressed wood is held in the mold, and the heat treatment is performed for about 10 minutes at a high temperature of about 180 ° C. to fix the compression structure, and then the mold is cooled and the molded product is taken out. . However, in any of the methods, the time required for wood to stay in the compression device including the mold, that is, the occupation time of the compression device, is long. There is a problem of being connected.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been proposed in view of such circumstances, and is intended to economically and efficiently compress wood made of soft conifers such as cedar.
An object of the present invention is to provide a method of forming wood for producing robust wood.

[0005]

That is, a first aspect of the present invention is a free water reducing step in which coniferous wood is compressed in a softened state to release free water from the wood, and after the free water is reduced. Of the wood in a softened state into the pressure vessel,
A compression step of compressing with a liquid pressure in the pressure vessel, a shaping jig insertion step of inserting the compressed wood into a cylindrical shaping jig connected to the pressure vessel, Releasing the shaping jig and heating the wood in the shaping jig to soften and reduce the volume, thereby reducing the volume of the surface of the wood to the inner surface of the shaping jig; The present invention relates to a method for molding wood, comprising a step of taking out the wood from the shaping jig after drying the wood in the jig.

According to a second aspect of the present invention, there is provided a free water reducing step in which coniferous wood is compressed in a softened state to release free water from the wood, and the wood after the free water reduction is softened in a softened state. A compression step of leading into the pressure vessel and compressing with the liquid pressure in the pressure vessel, and reducing the temperature of the liquid until the compressed state of the wood is fixed while maintaining the pressure in the pressure vessel to reduce the temperature of the wood. After cooling, the compressed wood is removed from the pressure-resistant container, the compressed wood is removed, the compressed wood is inserted into a cylindrical shaping jig, and the wood in the shaping jig is heated. By softening and reducing the volume, a volume relaxation step of pressing the surface of the wood to the inner surface of the shaping jig, and drying the wood in the shaping jig, from the shaping jig, It is a product removal process that takes out wood It becomes possible according to the molding method of the timber according to claim.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the invention described in claim 1 will be described. The method of the present invention comprises:
It comprises a compression step, a shaping jig insertion step, a volume relaxation step, and a product removal step.

[0008] As the wood formed by the method of the present invention, a suitable conifer such as cedar or larch is selected, and a tree obtained by cutting off the branches and leaves is used. The bark may be left as it is, but preferably has no crack on the wood surface. In this embodiment, cedar is used.

The free water lowering step is for compressing the softwood wood in a softened state so that free water in the wood tissue is released from the cleave surface, whereby the wood tissue is crushed in the subsequent compression step. This makes it possible to efficiently compress the wood in the radial direction.

FIG. 1 shows a wood compression apparatus preferably used in the free water lowering step. Reference numeral 10 denotes wood, and reference numeral 20 denotes a compression device. As shown, the compression device 20
Are molds 21 and 21 having a semi-cylindrical cross section and molds 21 and
1 is attached to a base 23. The molds 21 and 21 are arranged so that their curved inner surfaces face each other to form a compression space 24 therein, and one (the upper mold in this example) is at an appropriate speed with respect to the other. It is designed to move forward and backward.

The wood 10 has an end diameter of about 11 to 13 c.
After being lumbered to a length of about 1.2 m and subjected to a wet heat treatment in steam at 100 ° C. for 18 hours, an appropriate number of them are arranged in the compression space 24 of the compression device 20. The compression device 20
Is adjusted to 100 ° C., and the upper mold 21 is
By advancing toward the lower mold at a speed of cm / min, the wood 10 in the compression space 24 is compressed to release free water inside the wood. As described above, by preliminarily softening the wood 10 by the wet heat treatment, the wood is easily compressed. Further, by this step, the cross-sectional area in the wood 10 is reduced to about 1/3 before compression. Then, immediately after the compression is completed, the mold 21 is retracted. With the retreat of the mold 21, the compressed wood recovers its volume almost before compression. Subsequently, the recovered wood 10
From the compression device 20.

Here, softening of wood will be described. That is, in order to soften wood, it is necessary to heat wood at a temperature higher than the glass transition temperature (Tg) of lignin contained in the wood. Lignin binds crystalline cellulose fibrils, which are the main components of wood, to maintain the physical strength of wood, and is itself a non-crystalline polymer. The glass transition temperature of this lignin is around 200 ° C. in a dry state, but drops to around 100 ° C. at a moisture content that removes all free water. Therefore, generally, wood in an undried state is softened when heated to about 100 ° C., and its shape can be reversibly changed by an external force.

Wood 1 taken out of the compression device 20
If 0, then the compression step is performed. At this time, since the wood 10 taken out of the compression device 20 is in a softened state, all the wood 10 is temporarily stored in hot air of about 100 ° C. to keep the softened state, and one piece of wood is removed from the wood 10 as necessary. It is preferable to take them out one by one and proceed to the next compression step.

By the way, the wood 10 which has been compressed and the free water has been released as described above has a state in which mass transfer in the axial direction is easy because the partition wall in the tracheid is broken. Therefore, at the time of hydraulic compression performed in this compression step, the liquid penetrates into the wood through the lip surface,
May interfere with effective compression. To prevent that,
It is desirable to prevent the intrusion of moisture by coating the cleave surface with a polymer having low permeability to liquid or covering it with a stretchable sheet or film such as rubber. Further, in this case, it is preferable that the corners of the opening edge be dropped with a plane or the like without breaking the film or the like. In this embodiment, after the wood 10 is taken out from the compression device, the edges of both ends of the wood 10 have a thickness of 0.5 mm.
Was covered with a silicone rubber sheet, and a rubber string was wound several times and tightened and fixed.

FIG. 2 shows a compression device 30 preferably used in this compression step. As shown, the compression device 30 includes a pressure vessel 31 and an insertion member 32, and includes a water tank 33 and a pump.

The pressure-resistant container 31 is formed in a substantially cylindrical shape having a diameter into which the wood 10 after the free water lowering step can be inserted. One end is a wood insertion portion 35, and the other end is a cylindrical shaping jig 40 described later. Of the connecting part 36 of FIG. This pressure-resistant container 31 compresses the wood 10 in the container by sealing the wood insertion portion 35 and the connection portion 36 with lids 37 and 38 and pressing a predetermined amount of liquid into the inside. It is desirable for the structure to withstand a pressure of about the atmospheric pressure. The wood insertion portion 35 has the wood 1 compressed in the pressure vessel 31.
An insertion member 32 that inserts 0 into the cylindrical shaping jig 40 is attached.

The connecting portion 36 is formed in a cylindrical shape having an inner diameter smaller than that of the pressure-resistant container 31, and is provided continuously with the pressure-resistant container 31. Inside the connecting portion 36, a cylindrical shaping jig 40 is detachably mounted. In this embodiment, the cylindrical shaping jig 40 is accommodated in the connecting portion 36 of the pressure-resistant container 31. However, the structure of the connecting portion 36 is not limited to this.

The water tank 33 is filled with a liquid L such as water or oil, and a predetermined amount is continuously or intermittently introduced or discharged into the pressure vessel 31 by a pump 34. The fluid pressure can be increased or decreased.

The cylindrical shaping jig 40 is for inserting the wood 10 compressed by the liquid pressure of the pressure-resistant container 31 and giving a predetermined shape to the wood by volume reduction described later. The shape should conform to the required shape of the wood, such as the shape or the shape of a square tube. In this embodiment, it is formed in a cylindrical shape with an inner diameter of 10 cm from a stainless steel plate having a thickness of 2 mm.

In the compression step, first, the wood 10 having passed through the free water lowering step is transferred from the wood insertion portion 35 to the pressure vessel 3.
Guided into 1. Thereafter, the pump 34 is placed in the pressure vessel 31.
A liquid L such as water, and press the wood 1
Compress 0. In this embodiment, the wood 10 is introduced and the container 3
1 is sealed, and the liquid L is introduced into the container 31 by the pump 34.
(50 ° C. hot water) was introduced to raise the liquid pressure to 12 atm.

In the subsequent shaping jig insertion step, the wood 10 compressed by the hydraulic pressure is cylindrically shaped via the connecting portion 36 by the inserting member 32 while the hydraulic pressure in the container 31 is maintained. It is inserted into the jig 40. At that time, the cylindrical shaping jig 4
The inner diameter of 0 is 90 times the end diameter of the wood after the free water lowering step.
%, So if you do enough compression,
The compressed wood 10 can be easily inserted into the cylindrical shaping jig 40.

In the subsequent volume relaxation step, when the wood 10 is completely inserted into the cylindrical shaping jig 40, the pump 34 is stopped and the pressure-resistant container 31 is stopped.
Then, the liquid L in the cylindrical shaping jig 40 is discharged, and the pressure inside the container is returned to normal pressure. Then, the pressure vessel 31
Timber 10 together with the cylindrical shaping jig 40 from
Heated in saturated steam at 10 ° C. for 2 hours. By this treatment, the wood 10 is sufficiently softened, and is pressed against the inner surface of the cylindrical shaping jig by the volume relaxation force to be shaped, and at the same time, the internal stress of the wood 10 is also reduced. As described above, since the volume of the wood 10 is reduced in the cylindrical shaping jig 40, the product wood removed from the cylindrical shaping jig 40 in the subsequent product removal process hardly further reduces the volume. There is no danger that the shape of the wood will return to its original shape.

The reason for using the saturated steam in the heating is as follows. That is, since the wood in the above step was compressed in the liquid, at least the surface layer portion contains water at or above the fiber saturation point. The temperature at which wood softens (softening temperature) depends on the moisture content of the wood,
100 if the wood contains water above the fiber saturation point
It is known that the softening temperature rises as the water content decreases (drys), although it is around ℃. Furthermore, when softening and molding thick wood as in this example,
Prolonged heating is required. Therefore, by heating the wood in the atmosphere of saturated steam as described above, it is possible to prevent the surface layer of the wood from being excessively dried and to prevent the softening temperature from becoming high, thereby shortening the time and economically. It was made possible to reduce the volume.

Subsequently, a product take-out step is performed. In this step, first, the wood 10 is placed in the cylindrical shaping jig 40.
In a state where it is inserted in the inside, it is put into a drier or the like and heated and dried. Due to this drying, the wood 10 in the cylindrical shaping jig 40 slightly shrinks in the radial direction,
It can be easily taken out from the cylindrical shaping tool 40. In the present example, the wood 10 was taken out from the cylindrical shaping jig 40 after being exposed in an air bath at 110 ° C. for 5 hours, further dried at 80 ° C. under a reduced pressure of 20 mmHg.
In addition, the rubber sheet covering the front end of the wood was removed from the wood 10 before entering the volume relaxation step. The obtained product wood was formed in a cylindrical shape having a diameter of 10 cm and high roundness, and the surface hardness was much improved as compared with the cedar log.

Next, a molding method according to a second aspect will be described. The molding method of the present invention includes a free water lowering step, a compression step, a compressed wood removal step, a shaping jig insertion step, a volume relaxation step, and a product removal step. This free water lowering step is the same as the free water lowering step performed by the molding method described in claim 1, and therefore the description is omitted.

That is, in the compression step of this method, the wood that has passed through the free water reduction step is introduced into a pressure-resistant container in a softened state, and the liquid is pressed into the pressure-resistant container by a pressure pump and compressed at once. For economy of the process, it is desirable to determine the shape of the pressure vessel to a size that can process a large number of woods simultaneously. In this embodiment, the apparatus was compressed with hot water at 50 ° C. using the apparatus shown in FIG. 2 in which a pressure regulating valve was connected to the pressure vessel.

In the subsequent step of removing the compressed wood, first, while maintaining the liquid pressure in the pressure vessel, the liquid temperature in the pressure vessel is reduced until the compressed state of the wood is temporarily fixed. Cool the wood. Specifically, while continuously feeding cold water into the pressure-resistant container by another pump, the liquid is discharged from the container via a pressure regulating valve or the like to cool the wood to a temperature lower than the softening temperature. In this embodiment,
Cooled using cold water at 20 ° C. By this cooling, the wood is fixed in a compressed state in the pressure vessel. Thereafter, the pressurized state in the pressure-resistant container is released, and the wood is taken out of the container. The taken out wood is maintained in the same compressed state as in the pressure vessel.

In the shaping jig insertion step to be performed next, the compressed wood taken out of the pressure-resistant container in the previous step is quickly inserted into the cylindrical shaping jig. As the cylindrical shaping jig, the same one as the cylindrical shaping jig 40 shown in FIG. 2 can be used.

Next, a volume relaxation step is performed. In this step, the wood is heated while being inserted into the cylindrical shaping jig to be in a softened state. As a result, the wood is reduced in volume and expands radially, and its surface is pressed against the inner surface of the cylindrical shaping jig. The heating temperature at that time was set to a temperature higher than the temperature at which the wood was softened. In this embodiment, the heating was performed in saturated steam at about 100 ° C. for 2 hours. By this volume relaxing step, the wood is shaped into the shape of the inner surface of the cylindrical shaping jig.

In the subsequent product removal step, first, the wood is dried while being inserted into the cylindrical shaping jig, and slightly shrunk in the radial direction so that the wood can be easily removed from the cylindrical shaping jig. I do. Then, the dried and shrunk product wood is taken out of the cylindrical shaping jig. In this example, the product wood was dried in an air bath at 110 ° C. for 5 hours, and further dried at 80 ° C. under a reduced pressure of 20 mmHg for 4 hours. The obtained product wood was formed in a columnar shape with high roundness, and the surface hardness was much improved as compared with the cedar log.

[0031]

As shown and described above, according to the method for molding wood of the present invention, the free water is reduced and the softened wood is compressed by the liquid pressure in the pressure vessel.
Compression is easy and reliable.

According to the method of molding wood of the present invention, the wood compressed in the pressure vessel as described above is inserted into the cylindrical shaping jig, and the wood in the cylindrical shaping jig is removed. Since the volume is alleviated outside the pressure vessel, the occupancy time of the compression device including the pressure vessel and the pump and the like connected thereto can be shortened, and the wood can be formed efficiently and economically. Therefore, even when processing a large amount of wood,
A compression device composed of a pressure-resistant container or the like can be used efficiently and becomes economical. In addition, since a large number of cylindrical shaping jigs can be used and the volume of the wood inserted into the cylindrical shaping jig can be reduced as a whole, the working efficiency can be improved. Furthermore, the obtained wood is formed with high rigidity and high precision, and is of extremely high practical value.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a compression device for reducing free water used in a method of the present invention.

FIG. 2 is a cross-sectional view illustrating an example of a pressure-resistant container used in the method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Wood 20 Compressor for reducing free water 21 Mold 30 Compressor 31 Pressure vessel 40 Cylindrical shaping jig

Claims (2)

(57) [Claims] 1. A free water lowering step of compressing wood made of softwood in a softened state and releasing free water from the wood; and guiding the wood after the free water reduction in a softened state into a pressure-resistant container. A compression step of compressing with the liquid pressure in the inside; a shaping jig inserting step of inserting the compressed wood into a cylindrical shaping jig connected to the pressure-resistant container; and a shaping jig from the pressure-resistant container. Releasing the tool and heating the wood in the shaping jig to a softened state to relax the volume, thereby reducing the volume of the surface of the wood to the inner surface of the shaping jig; Drying the wood and then removing the product from the shaping jig. 2. A free water lowering step of compressing wood made of softwood in a softened state and releasing free water from the wood; and guiding the wood after free water reduction in a softened state into a pressure-resistant container. A compression step of compressing with the liquid pressure in the vessel, and cooling the wood by lowering the temperature of the liquid until the compressed state of the wood is fixed while maintaining the pressure in the pressure vessel, and then compressing from the pressure vessel. A compressed wood removing step of removing the wood, a shaping jig inserting step of inserting the compressed wood into a cylindrical shaping jig, and heating the wood in the shaping jig to a softened state to relax the volume. A volume relaxation step of pressing the surface of the wood to the inner surface of the shaping jig, and a product removing step of removing the product from the shaping jig after drying the wood in the shaping jig. Characterized by the fact that Method.