JP3580537B2 - Wood forming apparatus and wood forming method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wood forming apparatus and a wood forming method for obtaining decorative wood having an uneven pattern on a surface used for furniture, building materials, musical instruments, and the like.
[0002]
[Prior art]
BACKGROUND ART Wood materials made of plate-like wood or wood powder having a concavo-convex pattern on the surface are expected to be used in various applications from the viewpoint of decorativeness.
As a method of forming an uneven pattern on the surface of wood, a method of carving the surface of wood with a chisel has been known for a long time. However, when the uneven pattern is formed by the engraving, there are problems that it takes a long time for the engraving operation and that it is difficult to obtain a uniform uneven pattern.
On the other hand, if a hard board or MDF formed by bonding wood powder with a phenol resin is subjected to secondary processing by engraving or the like, in addition to the above-mentioned problems with wood, biodegradation is required. Since waste materials containing phenol having no properties are produced, it is not preferable from the viewpoint of environmental consideration.
[0003]
In view of the above circumstances, in recent years, a method has been developed in which a wood material is impregnated with a low-molecular-weight phenol resin, dried, softened, pressed, and fixed in shape to obtain molded wood having a desired shape.
Here, in the present specification, the low-molecular-weight phenol resin refers to a phenol monomethylol (salinigen), a dimethylol, a trimethylol, and a polymer of these methylol compounds. .
[0004]
[Problems to be solved by the invention]
However, the conventional method of molding a wooden material by impregnation with a phenol resin has the following problems.
[0005]
In other words, when using wood such as a plate, emphasis is placed on decorativeness, and when forming a concavo-convex pattern such that the compression ratio is greatly changed between the concave and convex portions of the pattern, the surface or inside of the molded wood, There is a problem that cracking, peeling, tearing in the fiber direction, and the like increase. Further, when the compression ratio is high, evaporation of the phenol volatile material and water is hindered, so that there is a problem that productivity is deteriorated.
On the other hand, in order to avoid the above problem by adjusting the height of the convex pattern to be formed or the depth of the concave pattern in order to reduce the defective rate at the mass production level, incomplete transfer results. Therefore, there is a problem in that it becomes impossible to form molded wood having excellent decorativeness.
[0006]
On the other hand, when wood powder is used, cracks and the like are less likely to occur than in the case of plate-like wood. In this case, there is a problem that productivity is deteriorated because evaporation of the phenol volatile material and water is prevented.
In addition, there is also a problem that physical properties such as strength, for example, of the interior after the molding are varied, and cracks are generated from a portion having a low strength, so that a product having stable quality cannot be provided.
[0007]
The present invention has been made in view of the above problems, and therefore, the present invention can significantly improve the compression depth and the limitation of the curvature of a pattern when treating a wood material using a low-molecular-weight phenol resin, and can improve the decoration. Provided is a wood forming apparatus and a wood forming method for forming formed wood which is excellent in property and can reduce cracks, peeling, tearing in the fiber direction, and the like on the material surface and inside, and can achieve stable quality at a mass production level. The purpose is to:
[0008]
[Means for Solving the Problems]
To achieve the above object, the wood forming apparatus of the present invention is a pair of press dies having an uneven pattern to be impregnated with a phenol resin and transferred to a softened wood material,A metal frame having an opening through which the pair of press dies sandwiching the wood material is inserted and into which a protruding jig for releasing can be inserted, and the pair of presses between the metal frame; A pressed portion having a spacer that sandwiches a mold, and a press portion that presses the metal frame and the spacer of the pressed portion,The pair of press dies have a concavo-convex pattern in which the concave portion of one press die and the convex portion of the other press die substantially overlap each other.
[0009]
Preferably, there is further provided a heating means for heating the wood material to a predetermined temperature to harden the wood material after compression molding to fix the shape.
[0010]
Further, in order to achieve the above object, the wood molding method of the present invention is an impregnation step of impregnating a wood material with a phenol resin, and a softening step of heating and softening the wood material impregnated with the phenol resin,A pre-compression step of compressing the wood material in a heating state and compressing the wood material in a direction different from a compression direction for forming an uneven pattern of the wood material,Compressing the wood material from at least both sides, comprising a compression step of forming an uneven pattern on both sides of the wood material, and a curing step of heating and curing the wood material in the compressed state, after shape fixing The thickness of the molded wood is substantially uniform inside thereof, and the formed wood having the inverted concave pattern is formed on the other surface opposite to the surface on which the convex pattern is formed.
[0011]
According to the present invention described above, the woody material such as plate-like wood or wood powder is heated and dried in a state where the cell wall is impregnated with the phenol resin, so that the internal temperature is increased and the wood material is softened. Become.
In this softened state, the press mold is operated to compress the wood material, transferring the uneven pattern to the wood material, and heating while maintaining the compressed state, so that the phenol resin is in the cell wall. , And the shaping of the wood by compression is fixed, and the subsequent heating or water absorption forms stable shaped wood that does not return to the shaping.
In the above operation, as a press die for transferring a concavo-convex pattern to a wood material, a press die having a concavo-convex pattern in which the concave portion of one press die and the convex portion of the other press die substantially overlap each other. By using, because the thickness of the molded wood after transfer becomes substantially uniform, the compression ratio becomes substantially uniform, the reaction mechanism of softening, shape fixing is stabilized, and cracks, peeling, tearing in the fiber direction, etc. The disadvantage can be suppressed.
[0012]
Preferably, before the compression step, the method further comprises a pre-compression step of compressing the wood material in a heating direction and in a direction different from a compression direction for forming the uneven pattern of the wood material.
As a result, the pre-compressed wood becomes extremely easy to be compression-molded, and the subsequent compression-molding can be performed smoothly.
[0013]
Preferably, in the impregnation step, the wood material is impregnated with a low-molecular-weight phenol resin having an average molecular weight of 200 to 500.
This means that if the average molecular weight is less than 200, the number of methylol groups contained per unit phenol skeleton is small, so that the crosslink density is small, the effect of hardening the molded wood is small, and the molded wood having a stable shape is provided. It becomes difficult to do so.
On the other hand, when the average molecular weight is larger than 500, the amount of the phenol resin retained on the cell wall of the woody material is reduced, and the effect of softening and hardening the woody material is small, and it is difficult to provide molded wood having a stable shape. Because.
[0014]
Preferably, in the impregnation step, the wood material is immersed in an aqueous solution having a low molecular weight phenol resin concentration of 3 to 15% by weight to impregnate the phenol resin.
Further, the concentration of the low molecular weight phenol resin in the phenol resin solution is more preferably 5 to 10% by weight.
This is because, when the concentration of the phenolic resin is lower than 3% by weight, the amount of the phenolic resin retained on the cell wall of the woody material is reduced, and the shape of the molded wood is less fixed in the subsequent curing step, and has a stable shape. This is because it becomes difficult to provide molded wood.
On the other hand, if it is higher than 15% by weight, the specific gravity of the obtained molded wood becomes too large.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of a wood forming apparatus and a wood forming method according to the present invention will be described with reference to the drawings.
[0016]
First embodiment
FIG. 1A is a perspective view showing an example of molded wood formed by the wood molding apparatus of the present invention, and FIG. 1B is a schematic enlarged cross section taken along line AA of FIG. 1A. FIG.
[0017]
As shown in FIG. 1, a molded wood 10 is formed by compressing a plate-like wood impregnated with a phenolic resin or a woody material such as wood powder to form a predetermined surface on a flat surface 11 having a substantially smooth surface. The protruding pattern 12 protruding in a protruding shape is formed clearly and beautifully in appearance.
[0018]
The molded wood 10 is compressed in a direction substantially perpendicular to the fiber direction (radial direction or tangential direction) when, for example, plate-shaped wood is used.
Here, the fiber (Textile) direction L is a direction along the grain, and the radiation direction R is orthogonal to the fiber direction L and refers to a direction from the center of the tree to the outside or from the outside to the center. Tangential direction T means the direction of the tangent to the annual ring.
[0019]
For example, a convex pattern is formed on the surface of the molded wood 10, and a concave pattern that is the reverse of the convex pattern on the surface is formed on the back surface of the molded wood 10.
That is, as shown in FIG. 1 (b), for example, a convex pattern 12a having a height a is formed on the surface of the molded wood 10, and a concave pattern 13a having a depth a is formed on the rear surface immediately below the same. ing. Accordingly, the convex pattern 12a on the front surface and the concave pattern 13a on the rear surface have inverted shapes.
[0020]
As described above, for example, the convex pattern 12a is formed on one surface of the molded wood 10 and the concave pattern 13a having an inverted shape of the convex pattern is formed on the other surface, so that the thickness in the molded wood 10 is reduced. Almost constant (t_b1= T_b2= T_b3).
Here, the thickness of the woody material before compression molding is t_a  The thickness of the molded wood after compression molding is t_b  Then, the compression ratio c is expressed by the following equation (1).
[0021]
(Equation 1)
c (%) = ((t_a  -T_b  ) / T_a  ) × 100 (1)
[0022]
Therefore, the thickness in the molded wood after compression molding is substantially constant (t_b1= T_b2= T_b3), The compression ratio is substantially uniform in the molded wood.
[0023]
Next, a wood forming apparatus and a wood forming method of the present embodiment for forming the above-described formed wood will be described.
The wood molding method of the present invention is roughly divided into four steps: a phenol resin impregnation step, a drying and softening step, a compression and curing step, and a removal step. Hereinafter, each step will be described together with an apparatus to be used.
[0024]
Here, in the wood forming method of the present invention, it is preferable to use an air-dried wood material. Here, the air-dry state refers to a water-containing state when dried in the air, and is a state that contains moisture inside. The moisture content in the air-dried state varies depending on the method of drying wood and humidity, but is on average about 8 to 15%.
Air-dried wood materials are used because they are generally readily available.
The air-dried woody material is formed by an appropriate method such as natural drying and artificial drying using a dryer with controlled temperature and humidity.
[0025]
Phenolic resin impregnation process
FIG. 2A is a schematic configuration diagram of an impregnation device used in this step.
The impregnating device shown in FIG. 2A includes a pressure vessel 1, a water tank 3, a control device 20, a compressor 30, and the like.
[0026]
The pressure vessel 1 is made of a bottomed cylindrical body made of, for example, high-strength steel or stainless steel so as to withstand low pressure and high pressure, and a lid 1a is attached to the opening thereof so as to be openable and closable. In the pressure vessel 1, the pressure in the pressure vessel 1 is controlled through a pipe 21, the inside of the pressure vessel 1 is exhausted through a pipe 22, and an aqueous solution or the like remaining in the pressure vessel 1 is discharged outside through a pipe 23. Is done.
[0027]
The control device 20 performs various controls, and controls each valve (22a, 23a) by air pressure from a compressor (compressor) 30. Specifically, while monitoring the pressure through a pressure gauge (not shown) provided in the pressure vessel 1, the pressure in the pressure vessel 1 is reduced through a pipe 21 through a vacuum pump (not shown) while monitoring the pressure. , And pressurized through a compressor 30.
Further, the pressure in the pressure vessel 1 that has been reduced or increased is returned to the normal pressure by adjusting the exhaust valve 22a of the pipe 22 that communicates with the external atmosphere.
Further, the discharge control of the aqueous solution in the pressure vessel 1 generated by the decompression or pressurization is performed by adjusting the drain valve 23a.
Also, it is electrically connected to the lid 1a, and controls opening and closing of the door.
The time in each step can be monitored via a clock (not shown).
[0028]
FIG. 2B is a schematic enlarged sectional view of the water tank 3.
As shown in FIG. 2 (b), for example, a plate-like wood 10a sinks in a water tank 3 having an aqueous phenol resin solution 31, and is coated with wood to prevent the wood 10a from floating, and a net 32 is formed. And a weight 33 are provided.
[0029]
The low molecular weight phenol resin used in the present invention preferably contains as many methylol groups as possible per unit phenol skeleton in order to increase the crosslink density contributing to curing.
That is, the average molecular weight of the phenol resin impregnated in the phenol resin impregnation step is preferably 200 to 500.
This means that if the average molecular weight is less than 200, the number of methylol groups contained per unit phenol skeleton is small, so that the crosslink density is small, the effect of hardening the molded wood is small, and the molded wood having a stable shape is provided. It becomes difficult to do so.
On the other hand, when the average molecular weight is larger than 500, the amount of the phenol resin retained on the cell wall of the woody material is reduced, and the effect of softening and hardening the woody material is small, and it is difficult to provide molded wood having a stable shape. Because.
[0030]
The concentration of the low-molecular-weight phenol resin in the aqueous phenol resin solution 31 is preferably 3 to 15% by weight, and more preferably 5 to 10% by weight. This is because, when the concentration of the phenolic resin is lower than 3% by weight, the amount of the phenolic resin retained on the cell wall of the woody material is reduced, and the shape of the molded wood is less fixed in the subsequent curing step, and has a stable shape. This is because it becomes difficult to form molded wood.
On the other hand, if it is higher than 15% by weight, the specific gravity of the obtained molded wood becomes too large.
[0031]
A method of impregnating wood material of phenol resin using the above impregnating apparatus will be described.
First, the lid 1a at the opening of the pressure vessel 1 is opened, the pressure vessel 1 is opened, and the water tank 3 is carried into the pressure vessel 1 and placed on the gantry 2.
Next, after closing the lid of the pressure vessel 1 and sealing the pressure vessel 1, the inside of the pressure vessel 1 is evacuated through the pipe 21 to reduce the pressure to, for example, about -740 mmHg on the basis of the atmospheric pressure. The depressurized state is maintained for 60 minutes, after which the exhaust valve 22a is adjusted to return to normal pressure by the pipe 22, and then the pressure inside the pressure vessel 1 is set to, for example, +8 kg / cm based on the atmospheric pressure.²  The phenolic resin is impregnated into the cell wall of the wood 10a by maintaining the pressurized state for about 10 minutes.
[0032]
In the case where wood powder is used, the phenol resin can be impregnated by omitting the steps of reducing pressure and increasing pressure in the above steps.
[0033]
Drying / softening process
FIG. 3 is a cross-sectional view of a blow dryer used in the drying and softening process.
The wood 10a after the phenol resin impregnation step is carried into a blow dryer so that the woods 10a do not contact each other, and blow drying is performed.
[0034]
In the present embodiment, drying is performed in the following three steps.
First, blast drying is performed at 30 ° C. The time for performing the blast drying is appropriately determined according to the size of the wood, and is about 24 hours. In addition, it is preferable that this blast drying step be as long as possible in order to prevent deformation or depression of wood due to rapid drying in the subsequent blast drying.
Next, blast drying is performed at 60 ° C. The time for performing the blast drying is also appropriately determined according to the size of the wood, but is about 48 hours.
Next, blast drying is performed at 80 ° C. The time for performing the blast drying is also appropriately determined according to the size of the wood, but is about 72 hours.
In addition, it is also possible to perform natural drying instead of the air drying at 30 ° C.
Further, if the drying is performed too rapidly at an excessively high temperature, the drying speed becomes too fast, and deformation such as warping or twisting of the wood or depression occurs, which is not preferable.
[0035]
Compression and curing process
FIG. 4A is a front view of the wood forming apparatus according to the present embodiment, and FIG. 4B is a side view of the wood forming apparatus.
The wood forming apparatus shown in FIG. 4 includes a press cylinder 41 attached and fixed to the upper outside of the forming chamber 40 by appropriate means, a piston rod 42 penetrating the peripheral wall of the forming chamber 40, and a tip end of the piston rod 42. A movable heater press plate 43 having a built-in heater 43a is provided.
In addition, a fixed heater press plate 45 having a built-in heater 45 a fixed to the gantry 44 is provided at a lower portion in the molding chamber 40.
[0036]
The control device 46 is connected to the press cylinder 41, the heater 43a built in the movable heater press plate 43, and the heater 45a built in the fixed heater press plate 45, and controls the press of the movable heater press plate 43 (for example, force). , Speed) and the temperature of the movable and fixed heater press plates (43, 45) via the heaters (43a, 45a).
[0037]
The compression molding is performed by sandwiching the dried and softened woody material 10a with a mold to form a pressed portion to be molded, and carrying the pressed portion to be molded into the above-described wood forming apparatus.
FIG. 5 is a perspective view showing a configuration of a pressed portion to be formed.
As shown in FIG. 5A, the lower mold 7, the wood material 10a, the upper mold 8, and the spacer 9 are set in a metal frame 6 having a U-shaped groove, as shown in FIG. 5B. The pressed part 4 to be formed as described above is constituted.
On the opposing surface of the press die composed of the upper die 8 and the lower die 7, an uneven pattern (not shown) for transfer to a wood material is formed. The concavo-convex pattern of the upper mold 8 and the lower mold 7 has a concavo-convex pattern of an inverted shape. Therefore, when the opposing surfaces of the upper mold 8 and the lower mold 7 are combined, for example, the convex pattern of the upper mold 8 becomes lower. For example, it is formed so as to be fitted in a concave pattern.
The spacer 9 is for determining the thickness of the molded wood 10, and can be appropriately replaced according to the desired thickness of the molded wood 10.
[0038]
Next, a method of performing compression molding using the wood molding apparatus according to the present embodiment and curing the phenol resin to fix the shape of the molded wood will be described.
FIG. 6 is an enlarged view of a portion F in FIG.
First, as shown in FIG. 6A, a mold in which the wood 10a is not set is placed on the fixed heater press plate 45, and the movable heater press plate 43 is brought into contact with the mold. The mold is heated to, for example, about 160 ° C.
[0039]
Next, the mold is taken out of the wood forming apparatus, and the wood 10a of about 80 ° C. after heating and drying is set to form a pressed part 4 to be formed. As shown in FIG. The press-formed portion 4 is placed on the fixed heater press plate 45 thus set, and the wood 10a is heated.
[0040]
Next, as shown in FIG. 6 (c), the movable heater press plate 43 is lowered to press the spacer 9 of the press-formed part 4, and the movable and fixed heater press plates (43) are kept in the pressed state. , 45) is maintained at, for example, 160 ° C., and the wood 10a is heated, for example, for about 30 minutes.
[0041]
Through the above steps, the phenol resin impregnated in the cell walls of the wood 10a is cured, and the shape of the compression-molded wood 10a is fixed.
[0042]
Removal process
Next, the molded wood is taken out to reach the molded wood shown in FIG.
[0043]
The wood forming apparatus and the wood forming method according to the above-described embodiment have the following effects when using plate-like wood and wood powder as wood materials.
[0044]
When using plank wood
In this case, since the compression ratio is relatively uniform, it is possible to minimize the disadvantages such as surface or internal cracking, peeling, and tearing in the fiber direction of the formed wood while minimizing the disadvantages. The transferability of a pattern to wood can be improved, and stable quality can be achieved at a mass production level.
In addition, since the compression ratio to the wood is relatively uniform, the surface accuracy of the surface of the molded wood 10 is determined by the surface accuracy of the finish of the upper die 8 and the lower die 7, so that the quality can be stabilized without polishing later. Can be achieved.
Further, even if a crack occurs during compression molding, it can be fixed in the shape of the upper mold 8 and the lower mold 7 because it is restrained by the upper mold 8 and the lower mold 7.
In addition, the compression depth, the curvature, and the limitation of the compression ratio of the pattern to be transferred to the wood can be greatly improved, and the degree of freedom in design can be increased.
[0045]
When using wood powder
In this case, since the compression ratio is relatively uniform, the physical properties such as the strength of the molded wood are uniform, and the molded wood having stable quality can be formed.
Since the compression ratio is relatively uniform, there is little color unevenness in the portion darkened by the compression, and the subsequent colored coating becomes easy.
In addition, cracks and the like are less likely to occur as compared with wood, so that a large uneven pattern can be formed without difficulty.
[0046]
Second embodiment
In this embodiment, it is substantially the same as the first embodiment, but when plate-like wood is used as the wood material, the upper die 8 and the lower die 8 of the molded wood 10 are expanded in the horizontal direction at the time of pressing. Since there are cases where it is difficult to release the mold from the metal frame 7 and the metal frame 6, the pressed portion to be formed has the following structure.
FIG. 7A is a front view of the press-formed part 4 after compression as viewed from the direction A in FIG. 5B, and FIG. 7B is a view illustrating the pressed part 4 as viewed from the direction B in FIG. It is a side view after compression.
As shown in FIG. 7A, taking into account the difficulty in releasing the molded wood 10 after compression from the mold (including the mold frame 6 in addition to the upper mold 8 and the lower mold 7), In the groove 6, a taper having an angle x (for example, 2 degrees) is provided.
An opening 6a is provided on the bottom surface of the metal frame 6, and a height at which the molded wood 10 sandwiched between the upper die 8 and the lower die 7 can be inserted into the opening 6a and the lower die 7 can be pressed. The mold is released by using the protruding jig 15 having the projection 15a.
With the above structure, as shown in FIG. 8A, the metal frame 6 is set on the protruding jig 15 so that the protrusion 15a is inserted into the opening 6a. By lowering the metal frame 6, the lower mold 7 is pushed by the projection 15a, and the molded wood 10 sandwiched between the upper mold 8 and the lower mold 7 is pushed out of the metal frame 6. Thereafter, as shown in FIG. 8B, the molded wood 10 is released from the mold by separating the upper mold 8 and the lower mold 7 from each other.
[0047]
Third embodiment
This embodiment is also substantially the same as the first embodiment, but when plate-like wood is used as the wood material, the upper die 8 and the lower die 8 of the formed wood 10 are expanded in the horizontal direction at the time of pressing. Since it may be difficult to release the mold from the mold 7 and the metal frame 6, the pressed portion to be formed has a structure as shown below.
9 (a) is a plan view of the molded wood 10 sandwiched between the upper mold 8 and the lower mold 7, FIG. 9 (b) is a plan view of the wood of FIG. 9 (a), and FIG. 9 (c) is FIG. FIG. 3A is a side view as viewed from the direction D in FIG.
As shown in FIG. 9A, clamps 16 are installed in advance at, for example, four corners of the lower mold 7, and the lower mold 7 is fixed to the metal frame 6, and the wood 10a to be molded is also shown in FIG. 9B. As described above, a compression mold is formed by setting the clamp 16 on the lower die 7 using a die that has been formed so as to conform to the shape of the lower die 7 on which the clamp 16 has been formed and protrude from the dies (7, 8).
After the compression molding, a force is applied to a portion of the molded wood 10 that protrudes from the molds (7, 8), and is lifted upward to be released from the lower mold 7 fixed to the mold frame 6. Thereafter, the molded wood 10 is released from the mold by releasing the upper die 8.
[0048]
Fourth embodiment
This embodiment is also substantially the same as the first embodiment, but when plate-like wood is used as the wood material, the upper die 8 and the lower die 8 of the formed wood 10 are expanded in the horizontal direction at the time of pressing. Since it may be difficult to release the mold from the mold 7 and the metal frame 6, the pressed portion to be formed has a structure as shown below.
FIG. 10 shows a schematic configuration diagram of the molded wood 10 sandwiched between the upper die 8 and the lower die 7. The upper die 8 and the lower die 7 shown in FIG. 10 have openings (8a, 7a), respectively.
Then, after taking out the molded wood 10 sandwiched between the upper mold 8 and the lower mold 7 from the metal frame 6 in the same manner as in the second embodiment, it is inserted into the openings (8a, 7a) and the molded wood 10 is pressed. A protruding jig 15 having a protruding portion 15a having a height that can be used is used.
That is, the molded wood 10 sandwiched between the upper mold 8 and the lower mold 7 is set on the protruding jig 15 so that the protruding portion 15a is inserted into the opening (8a, 7a). By lowering the lower mold 7, the molded wood 10 is pushed by the projection 15 a, and the molded wood sandwiched between the upper mold 8 and the lower mold 7 is released from the lower mold 7. Similarly, by releasing the molded wood 10 from the upper mold, the molded wood 10 is released from the mold.
[0049]
Fifth embodiment
In the present embodiment, the structure is substantially the same as that of the first embodiment, but when wood powder is used as the wood material, the structure of the pressed portion to be formed has the following structure. FIG. 11A is a top view of the metal frame 6 used for wood powder, and FIG. 11B is a side view of FIG. 11A viewed from the direction E.
In the metal frame 6 shown in FIG. 11, a side plate 17 is attached to an open side surface of the metal frame 6 by a bolt or the like.
As shown in FIG. 11B, an opening 6 a is provided on the bottom surface of the metal frame 6, and similarly to the second embodiment, the molded wood 10 sandwiched between the upper mold 8 and the lower mold 7 is moved to the metal frame. 6 was taken out.
The structure described above is such that when wood powder is used, if the side surface of the metal frame 6 is open, the wood powder overflows from the open side surface. This is to prevent a change in the compression ratio due to unevenness of the compression ratio.
[0050]
Embodiments of the wood forming apparatus and the forming method of the present invention are not limited to the above description.
For example, the manufacturing conditions such as temperature and time in each step of the present invention include the type of tree that is the source of the wood material 10a, the size of the wood material 10a, the physical properties (specific gravity, moisture content, etc.) of the wood material 10a, and the like. Various conditions can be adopted.
Further, the compression molding direction is not limited to the direction described in the present embodiment, and compression molding can be performed in various directions.
The shape of the concavo-convex pattern to be transferred to the wooden material 10a is not particularly limited. For example, in addition to a pattern combining linear, curved, and lattice shapes, a symbol, a numeral, a character, and the like, and a combination thereof are used. There may be.
In the removal step, a mold release agent may be applied to a mold in advance in order to facilitate release of the molded wood. The release agent may be a mixture of soybean lecithin and toluene at a weight ratio of 1: 9.
[0051]
It is also effective to pre-compress before the compression and curing steps.
For example, after preliminarily compressing the plate-shaped wood in a direction different from the direction in which the compression molding is performed in the heated state, the compression and hardening steps in the present embodiment are performed.
Wood pre-compressed in the heated state is in a state where it is extremely easy to compression-mold.
Thereby, subsequent compression molding can be performed smoothly, that is, cracks, tears, and peeling can be reduced, and stable quality can be ensured. In addition, since pre-compression is performed before the forming press, the process is very efficient.
In addition, various changes can be made without departing from the spirit of the present invention.
[0052]
【Example】
Hereinafter, an embodiment in which molded wood is formed using the wood molding apparatus according to the present invention will be described.
[0053]
First embodiment
First, using a cypress having a length in the R direction of 10 mm, a length in the L direction of 4.33 mm, and a length in the T direction of 1.3 mm, dynamics of wood at each temperature when impregnated with a phenol resin. The elastic modulus was measured.
[0054]
FIG. 12 is a graph of wood temperature and dynamic elastic modulus when impregnated with a phenol resin. The elastic modulus indicates a tensile elastic modulus in the R direction (radiation direction) of wood.
As shown in FIG. 12, the wood impregnated with phenol has a high elastic modulus up to about 50 ° C., but gradually decreases at a temperature of 50 ° C. or higher.
When the temperature reaches a temperature of about 130 ° C. or higher, the elastic modulus of the wood gradually increases, and when the temperature is about 160 ° C., the wood has a sufficient elastic modulus.
Thereby, in the drying and softening process of the present embodiment, the wood was blown and dried at 30 to 80 ° C., but it was confirmed that the wood was softened at the above temperature.
Further, in the curing step of the present embodiment, the wood impregnated with the phenol resin is heated at around 160 ° C., but it was confirmed that the wood impregnated with the phenol resin was cured at the temperature.
[0055]
Second embodiment
In the present embodiment, first, as a plate-like wood, perpok, Ramin, Meranti, Agathis, Poplar, Alder, Ayous, Unsugi, Radiata pine, Yonematsu, Rubber, Sen, Beech, Oak, Cedar, Hinoki, Japanese larch, Katsura And 19 types of natto were used, and a mixture of cedar and cypress having a size of 355 μm as wood powder was used, and compression molding was performed to form a concavo-convex pattern only on one side of the related art.
[0056]
Here, as the physical properties of the woody material used in this example, the total dry specific gravity, the air dry specific gravity, and the water content (%) were calculated.
[0057]
As a method of calculating the above physical property values, first, the length in the T direction (mm), the length in the R direction (mm), the length in the L direction (mm), and the total dry weight (g) of each wood in a completely dry state. Was measured, and the total dry specific gravity was calculated.
Next, for each wood, the length in the T direction (mm), the length in the R direction (mm), the length in the L direction (mm), and the dry weight (g) in the air-dried state were measured, and the air-dry specific gravity was calculated. .
Here, the L direction refers to a wood fiber (Textile) direction, the R direction refers to a radial direction, and the T direction refers to a tangential direction.
The completely dry state refers to a state in which the wood is dried at 100 to 110 ° C. until there is no change in weight, and the wood has almost no moisture absorbed.
The air-dried state refers to a state in which the air is dried in the air and contains moisture therein.
The above-mentioned total dry specific gravity and air dry specific gravity mean a value obtained by dividing a weight in a completely dry state or an air dry state by a volume.
[0058]
The moisture content u (%) is calculated by dividing the total dry weight by W₀  , Air dry weight W_u  Then, it is calculated by the following equation (2).
[0059]
(Equation 2)
u (%) = ((W_u  -W₀  ) / W₀  ) × 100 (2)
[0060]
FIG. 13 shows the calculation results of the total dry specific gravity, the air dry specific gravity, and the moisture content in the air dry state.
FIG. 13 shows the weights of three samples of each wood in the air-dried state and the fully-dried state, dimensions in the T direction, the R direction, and the L direction, and measured the total dry specific gravity, the air dry specific gravity, and the water content. The calculated average is shown.
For wood powder, only the water content is shown.
[0061]
In the wood forming apparatus according to the present embodiment, only the concave and convex pattern of the upper mold 8 is transferred to one surface of the wood material using the wood material of the air-dried state shown in FIG. 13, as shown in FIG. Molded wood having an uneven pattern on one side was formed.
Here, the wood used in the compression molding has a length in the T direction of 49.0 (mm), a length in the R direction of 12 (mm), and a length in the L direction of 280 (mm). It was compression molded in the R direction (see FIG. 1A).
The length of the molded wood after compression molding is 49.0 (mm) in the length in the T direction, 6 (mm) in the flat portion in the R direction, and 280 (mm) in the L direction. Met.
The upper die 8 and the lower die 7 have a width (corresponding to the T direction) of 50 (mm), a thickness (corresponding to the R direction) of 12 (mm), and a length (corresponding to the L direction) of 300 (mm). The material used was made of aluminum.
The upper mold 8 used had an uneven pattern to be transferred to a wooden material, and the lower mold 7 used was a flat article having no uneven pattern.
[0062]
Next, the manufacturing conditions will be described.
Phenolic resin impregnation process
First, a water tank 3 in which wood is immersed in an aqueous phenol resin solution having a phenol resin concentration of 10% by weight is placed on the gantry 2 of the pressure vessel 1, and the pressure is reduced under a reduced pressure of about -740 mmHg with respect to the atmospheric pressure. 60 minutes, then +8 kg / cm based on atmospheric pressure²  The wood 10a was impregnated with the phenol resin for 10 minutes under moderate pressure.
Drying / softening process
Next, air drying was performed at 30 ° C. for 24 hours, at 60 ° C. for 48 hours, and at 80 ° C. for 72 hours using a blow dryer.
Compression and curing process
Next, the mold in a state where the wood material 10a is not set on the fixed heater press plate 45 is heated to, for example, about 160 ° C., and then the wood material 10a is set and the fixed material heated to 160 ° C. The wood material 10a was heated on the heater press plate 45.
Thereafter, the wooden material 10a is pressed by the movable heater press plate 43, and the wooden material 10a is heated for 30 minutes while maintaining the movable and fixed heater press plates (43, 45) at, for example, 160 ° C. in the pressed state. Fixation was performed.
Removal process
Next, the above-mentioned wood was taken out to form a shaped wood having an uneven pattern on one side as shown in FIG.
[0063]
Thereby, the result about each wood shown in FIG. 14 was obtained.
In FIG. 14, cracking is an evaluation of the surface and internal state of the molded wood after compression molding in the case where an uneven pattern is formed on only one side, including peeling, tearing in the fiber direction, and the like.
The color unevenness is an evaluation of the color unevenness in the surface state of the dark-colored molded wood after compression molding.
In addition, the transferability is an evaluation of how beautifully the concavo-convex pattern of the upper die 8 is transferred to the molded wood.
The evaluation of the phenol resin impregnating property is an evaluation of whether or not the phenol resin is easily impregnated.
As shown in FIG. 14, when only the uneven pattern formed on the upper mold 8 is transferred and the uneven pattern is formed only on one side, there are few woods having no cracks and good transferability, and also impregnated with a phenol resin. There were some cases where the application of compression molding was suitable and others which were not.
[0064]
For example, poplars, alders, wigs, and the like were evaluated as being suitable when mainly evaluated for cracking and transferability.
Others were unsuitable and cracked on the surface to varying degrees.
[0065]
Next, the wood forming apparatus and the forming method of the present invention were applied to the perpock and the mixed wood powder of cedar and hinoki among the above plate-like wood.
The manufacturing conditions are such that, instead of the flat lower mold, a lower mold 7 in which an inverted concavo-convex pattern is formed with respect to the concavo-convex pattern formed in the upper mold 8 is used. went.
As a result, after compression molding, a molded wood made of a good perpoc having no cracks on the surface and excellent in transferability was formed.
Also, with respect to the wood powder, good molded wood having excellent transferability without cracking or uneven color on the surface was formed.
According to the above embodiment, in compression molding by the conventional phenolic resin impregnation treatment, even in a difficult-to-apply wood material, the disadvantage such as cracking is suppressed to a minimum by the wood molding apparatus and the molding method according to the present invention, It can be seen that high quality molded wood can be formed.
[0066]
【The invention's effect】
According to the wood molding apparatus of the present invention, since the compression ratio by press molding to a wood material is relatively uniform, there are disadvantages such as surface or internal cracking, peeling, and fiber direction tearing of the molded wood after compression molding. Can be minimized, and the transferability of the pattern to the wood material can be improved.
Therefore, it is possible to greatly improve the compression depth, the curvature, and the like of the pattern to be transferred to the wood material, and to increase the degree of freedom in design.
Further, since the compression ratio by press-molding the wood material is relatively uniform, the physical properties such as the strength of the molded wood are uniform, and the molded wood having stable quality can be formed.
[0067]
According to the wood molding method of the present invention, since the compression ratio by press molding to a wood material is relatively uniform, there are disadvantages such as surface or internal cracking, peeling, and fiber direction tearing of the molded wood after compression molding. Can be minimized, and stable quality can be achieved at the mass production level.
[Brief description of the drawings]
FIG. 1 (a) is a perspective view showing an example of molded wood according to the present invention, and FIG. 1 (b) is a schematic enlarged sectional view taken along line AA of FIG. 1 (a). .
FIG. 2 (a) is a schematic configuration diagram of an impregnation device of the present embodiment, and FIG. 2 (b) is a schematic enlarged sectional view of the water tank of FIG. 2 (a).
FIG. 3 is a sectional view of a blow dryer used in a drying / softening step.
FIG. 4 (a) is a front view of a wood forming apparatus according to the present embodiment, and FIG. 4 (b) is a side view of the wood forming apparatus.
FIG. 5A is a perspective view illustrating a configuration of a pressed section before setting, and FIG. 5B is a perspective view illustrating a configuration of a pressed section after setting.
FIG. 6 is an enlarged view of a portion F in FIG. 4 (a).
7A and 7B show a second embodiment, and FIG. 7A is a front view of a pressed portion to be formed as viewed from a direction A in FIG. 5B, and FIG. FIG. 5B is a side view after the compression of the pressed portion to be formed as viewed in the direction B in FIG.
FIG. 8 shows an example of a method for releasing molded wood.
FIG. 9 shows a third embodiment, FIG. 9 (a) is a plan view of molded wood sandwiched between an upper mold and a lower mold, and FIG. 9 (b) is a view of wood used. FIG. 9C is a plan view, and FIG. 9C is a side view as viewed from the direction D in FIG.
FIG. 10 shows the fourth embodiment, and shows one configuration example of a pressed portion to be formed when plate-like wood is used.
FIG. 11 shows the fifth embodiment, and shows one configuration example of a metal frame when using wood powder.
FIG. 12 is a graph showing the temperature and dynamic elastic modulus of wood impregnated with a phenolic resin.
FIG. 13 shows the calculation results of the total dry specific gravity, the air dry specific gravity, and the water content (%) of the woody material used in this example.
FIG. 14 shows an evaluation result when an uneven pattern is formed only on one surface.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Pressure vessel, 1a ... Lid, 2 ... Stand, 3 ... Water tank, 4 ... Molding press part, 6 ... Metal frame, 7 ... Lower mold, 8 ... Upper mold, 9 ... Spacer, 10 ... Molded wood, 10a ... Woody material (wood, wood powder), 11 flat part, 12 convex pattern, 15 projecting jig, 15a projecting part, 16 clamp, 17 side plate, 20, 46 control device, 21, 22, 23 ... piping, 22a, 23a ... valve, 30 ... compressor, 31 ... phenolic resin aqueous solution, 32 ... net, 33 ... weight, 41 ... press cylinder, 42 ... piston rod, 43 ... movable heater press plate, 43a ... heater, 44 ... Stand, 45 fixed heater press plate, 45a heater.

Claims (5)

A pair of press dies having an uneven pattern to be impregnated with phenolic resin and transferred to softened wood material,
A metal frame having an opening in which the pair of press dies sandwiching the wood material is accommodated, and in which a projecting jig for release can be inserted;
A spacer for sandwiching the pair of press dies between the metal frame and
A pressed portion having
A press unit for pressing the metal frame and the spacer of the pressed portion,
A wood forming apparatus, wherein the pair of press dies has a concavo-convex pattern in which a concave portion of one press die and a convex portion of the other press die substantially overlap each other. The wood forming apparatus according to claim 1, further comprising a heating unit configured to heat the wood material to a predetermined temperature to harden the wood material after compression molding to fix a shape. An impregnation step of impregnating the wood material with the phenolic resin,
A softening step of heating and softening the wood material impregnated with the phenolic resin,
A pre-compression step of compressing the wood material in a heating state and compressing the wood material in a direction different from a compression direction for forming an uneven pattern of the wood material,
A compression step of compressing the wood material from at least both sides to form an uneven pattern on both surfaces of the wood material;
A curing step of heating and curing the wood material in a compressed state,
A method of forming wood, wherein the thickness of the formed wood after fixing the shape is substantially uniform inside the wood, and the formed wood has an inverted concave pattern on the other surface opposite to the surface on which the convex pattern is formed. In the impregnation step,
The wood molding method according to claim 3, wherein the wood material is impregnated with a low molecular weight phenol resin having an average molecular weight of 200 to 500. In the impregnation step,
The wood molding method according to claim 4 , wherein the wood material is immersed in an aqueous solution having a low molecular weight phenol resin concentration of 3 to 15% by weight to impregnate the phenol resin .

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