JP2003011103A - Method for manufacturing wooden tray - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wooden tray which is excellent in stability of a shape. SOLUTION: In a method for manufacture of the wooden tray to obtain the wooden tray, a plain plate-like wood sheet comprising a first area 12 becoming a bottom plate part and a second area 13 arranged around the area 12 to become a wall plate part are pressed to form the tray consisting of the bottom plate part and the wall plate part arranged around the bottom plate part. A triangular area Δ of a corner part of the second area 13 is used as a compression area and the other part is used as a constriction area not compressed. By raising the second area 13 to either direction of front or rear of the first area 12, an excess area content generated following the simultaneous rise is made absorbed by compressing the triangular area Δ as a compression part 8. Then, a sticking plate is stuck with an adhesive so that the compression part 8 is not restored to obtain the wooden tray.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a wooden tray used as a packaging container for food or the like.

[0002]

2. Description of the Related Art Conventionally, a plastic tray made of expanded polystyrene or the like has been widely used as a packaging container for products such as foods. The main reason for this is that industrially produced plastic such as Styrofoam is inexpensive, and the material is homogeneous and easy to process. However, when plastic is disposed of by incineration or landfill, it may cause environmental pollution. for that reason,
Wood trays made of wood are being reviewed. For example, regarding a wooden tray, Japanese Patent Application Laid-Open No. 2000-2000
The manufacturing technique is disclosed in JP-A-52306, JP-A-8-25301, and the like.

[0003]

[Patent Document 1] Japanese Unexamined Patent Application Publication No.
In the method for forming a wooden tray according to No. 000-52306, a large number of thin wood plates and biodegradable sheets have to be prepared in order to manufacture the wooden tray. There is a problem of high cost. Further, the method of forming a wooden tray according to Japanese Patent Laid-Open No. 8-25301 has a problem in that the shape and size of the formed wooden tray are likely to be uneven because the shape restoring action of the wood is different for each thin wood plate used. is there. Further, since a material obtained by processing compressed wood into a thin wood plate is used as the material, the cost is also high. Further, in each of these conventional methods for forming a wooden tray, since the compression deformation is performed in one step by the tray-shaped press die, the portion to be compressed and the deformation amount are not controlled. For this reason, sometimes it is locally deformed excessively and cracks occur, and it is difficult to reliably suppress the shape restoring action, which tends to cause irregular shapes and dimensions. The present invention has been made by paying attention to the problems existing in such conventional techniques. The aim is to provide a wooden tray with excellent shape stability.

[0004]

In order to achieve the above object, in the invention according to claim 1, the first plate region is the bottom plate part and the wall plate part is arranged around the first region. A method of manufacturing a wooden tray, wherein a flat wooden thin plate having a second region is pressed to obtain a wooden tray including a bottom plate portion and a wall plate portion surrounding the bottom plate portion. A part of the second region is used as a compression region and the other part is used as a non-compressed restraint region, and the second region is erected with respect to the first region in either direction, front and back, and at the same time The gist is to absorb the excess area generated by compressing the compressed area in the width direction to form a compressed portion and then to perform a restoration preventing process so that the compressed portion is not restored. In the above-described configuration, for example, a flat wood thin plate is sandwiched by upper and lower molds and the second region is erected in either the front or back direction with respect to the periphery of the first region. At this time, the second area is compressed while the excess area generated by standing up is concentrated in the compression area to form a compression portion. On the other hand, the restraint region does not change due to the standing of the second region. However, since the compression part is compressed, it has a certain shape-retaining ability, but since it is not particularly adhered, it does not have a high shape-retaining ability.
In this way, restoration prevention processing is performed so as not to restore the compressed portion that is partially concentrated and compressed. As the restoration preventing process, for example, after compression, a flat thin plate may be attached onto the compression portion. Further, it is conceivable to apply an adhesive to a part of the second region to be the compression part before compressing the compression part.

According to the second aspect of the present invention, a flat plate-shaped thin wood plate having a first region which serves as a bottom plate portion and a second region which is arranged around the first region and serves as a wall plate portion is pressed. In a method for manufacturing a wooden tray, which is processed to obtain a wooden tray including a bottom plate portion and a wall plate portion surrounding the bottom plate portion, at least a part of the second region is defined as a first compression region. In addition, the other part is used as a non-compressed constrained region, and the first compressed region is compressed in the width direction to form a temporary compressed part and a permanent compressed part arranged at a predetermined position in the second region. In the processing step, the wall plate portion is erected with respect to the bottom plate portion, and at the same time, the temporary compression portion of the first compression region formed by the first processing step is restored, while the second region is raised in association with the erection. Do not restore the excess area that occurs in the permanent compression section. And a third processing step in which the wood thin plate processed by the second processing step is subjected to a restoration preventing process so that the permanent compressed portion is not restored. It is the gist of having adopted. In the above-described configuration, first, at least a part of the second region is used as the first compression region and the other part is used as the uncompressed constraint region in the first processing step, and only the first compression region is set in the width direction. Compress. There are two types of first compression areas formed at this time: a temporary compression section and a permanent compression section arranged at a predetermined position in the second area. Then, in the second processing step, the second region of the wood thin plate processed in this way is erected with respect to the first region. At the same time, the temporary compression portion is restored by the self-restoration action as it stands up, and the surplus area generated in the second region is absorbed by the permanent compression portion. That is, the surplus area, which is supposed to be generated by the standing of the second region, is offset by leaving it as a permanent compression unit that has been compressed in advance. In this way, restoration prevention processing is performed so as not to restore the permanent compression portion that is partially concentrated and compressed. As the restoration preventing process, for example, after compression, a flat thin plate may be attached onto the permanent compression part. Further, it is possible to apply an adhesive agent to a part of the second region that becomes the permanent compression portion at the time when the first processing step is completed.

In the invention described in claim 3, claim 1 or 2
In addition to the configuration of the invention described in (1), the main feature of the restoration prevention process is to attach a flat thin plate on the compression section so as to cover the compression section after the compression section is formed. With this, in addition to the above-mentioned action, the compression section can be prevented from being restored and the compression section can be hidden. According to a fourth aspect of the invention, in addition to the configuration of the invention according to any one of the first to third aspects, the bottom plate portion is rectangular, and the bottom plate portion is surrounded by four long wall plate portions from four sides. The gist of the invention is that the compression parts are arranged near the corners on a pair of opposing wall plates. In the invention described in claim 5, in addition to the configuration of any one of claims 1 to 4, the gist is that the compression portion is compressed in a direction intersecting with the fiber direction.

[0007]

According to the first and second aspects of the present invention, the second region overlaps when the second region is erected on either side of the first region with respect to the periphery of the flat plate-shaped thin wooden plate. The compression section and the uncompressed section are divided, and processing is performed so that the compression section will not be restored. Therefore, it is not necessary to perform the restoration preventing process on the entire wall plate portion constituted by the second region standing upright, the manufacturing work is simplified, and only the compression portion is partially deformed, so that the shape of the wooden tray is reduced. It has excellent stability. In the invention described in claim 3, the above-mentioned claim 1
In addition to the effect of any one of the inventions described in 2 and 3, since the restoration of the compressed portion can be prevented and the compressed portion can be hidden by sticking a flat thin plate, the appearance of the wooden tray is kept good. Be done. In the invention described in claim 4, in addition to the effect of any one of the inventions described in claims 1 to 3, since the compression part is provided near the corner where the excess area is most concentrated,
The compression is performed promptly, and as a result, the shape stability of the wooden tray is excellent. In the invention described in claim 5, in addition to the effect of the invention described in any one of claims 1 to 4, since it is compression in a direction intersecting with the fiber direction, it is easy to compress and the wood fiber is difficult to break, The strength of the compressed portion is unlikely to decrease and the appearance is less likely to be impaired.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A method according to an embodiment of the present invention will be described below with reference to the drawings. (Embodiment 1) As shown in FIG. 1, a wooden tray 1 as an example manufactured by the method of the present embodiment 1 has a main body 2 in which a thin wooden plate is compressed and deformed, and a main body 2 bonded to the main body 2.
It is composed of one attachment plate 3. The main body 2 includes a substantially rectangular bottom plate portion 5 and first and second wall plate portions 6 and 7 that surround the bottom plate portion 5 from four sides. The first wall plate portion 6 is disposed to face each other along the long side portion of the bottom plate portion 5, and the second wall plate portion 7 is provided.
Are arranged so as to face each other along the short side portion of the bottom plate portion 5. A compression portion 8 is formed near each end of each second wall plate portion 7. The compression portion 8 is a portion where a part of the second wall plate portion 7 is compressed when the first and second wall plate portions 6 and 7 are raised from the bottom plate portion 5, and is inclined according to the amount of compression. With first
The second wall plate portions 6 and 7 are raised from the bottom plate portion 5.

Each attachment plate 3 of this embodiment is attached to the second wall plate portion 7 with an adhesive. Sticking board 3
Is composed of a thin wooden plate having substantially the same shape as the second wall plate portion 7. In the state where each attachment plate 3 is attached to the second wall plate portion 7, the compression portion 8 is covered with the attachment plate 3 on the outer surface side of the second wall plate portion 7. As shown in FIG. 1, in the present embodiment, the fiber direction of the wooden tray 1 is the Y direction, that is, the direction substantially along the first wall plate portion 6. The fiber direction of the attachment plate 3 is the X direction, that is, the direction substantially along the second wall plate portion 7. That is, the attachment plate 3 is arranged in a direction substantially orthogonal to the fiber direction of the wooden tray 1.

Next, a method of manufacturing such a wooden tray 1 will be described. First, the thin wooden plate 11 as a raw material for the wooden tray 1 before forming will be described. As shown in FIG. 2, the wooden thin plate 11 is formed as a flat plate of a modified octagon. For convenience of explanation, numbers are sequentially assigned clockwise to each vertex of the thin wooden plate 11 with P1 at the upper left in the figure (P1 to P8). The rectangular portion surrounded by the broken line in the figure is the first region 12 which becomes the bottom plate portion 5. The vertices of the first area 12 are sequentially numbered clockwise (Q1 to Q4) with Q1 at the upper left of the drawing. A second region 13 surrounds the first region 12 in a band shape. The trapezoidal portion surrounded by P1, Q1, Q4, P8 and the trapezoidal portion surrounded by P4, Q2, Q3, P5 in the second region 13 are the portions that become the first wall plate portion 6 1 sub-region 15). Further, the deformed hexagonal portion surrounded by P1, P2, P3, P4, Q2, Q1 in the second region 13 and P5, P6, P7, P8, Q4, Q3.
The deformed hexagonal portion surrounded by is the portion that becomes the second wall plate portion 7 (this is referred to as the second sub-region 16). That is, the second area 13 is composed of the first and second sub areas 15 and 16.

In the first embodiment, the first sub-region 15 is a portion that does not expand or contract. On the other hand, the second sub-region 1
In FIG. 6, as shown in FIG. 2, a triangular portion surrounded by P2, Q1, and R1, a triangular portion surrounded by P3, Q2, and R1, a triangular portion surrounded by P6, Q3, and R1, P7,
A triangular portion surrounded by Q4 and R1 (this is referred to as a triangular area Δ) is indicated by diagonal lines Q1, R2 and R3, respectively.
Compressed to a triangle part surrounded by, a triangle part surrounded by Q2, R2, R3, a triangle part surrounded by Q3, R2, R3, and a triangle part surrounded by Q4, R2, R3 (that is, a compression part 8). It will be contracted. This is the second
This is because the surplus area due to the rising of the region 13 is compressed and absorbed. This compression direction is performed in a direction substantially orthogonal to the length direction of the wood fiber direction. In addition, R1 to R3 are P1 to P2, P3 to P4, P
5 to P6 and P7 to P8, which are theoretical points arranged at intermediate positions of line segments connecting the lines.

Next, a schematic structure of the first and second molds 20 and 21 for pressing the above-mentioned wood thin plate 11 will be described. The first and second molds 20 and 21 are molds having pressing surfaces of the same shape in which the bending directions of the mold pieces constituting the mold are opposite to each other. Therefore, only the first mold 20 will be described in detail, and the detailed description of the second mold 21 will be omitted. As shown in FIG. 4, the first mold 20 is composed of nine constituent members. First mold piece 2 in the center of the figure
5 presses the above-mentioned first region 12, and the first mold piece 2
The second mold pieces 26 on the left and right of 5 are the first sub-regions 15
Press respectively. In the figure, a third mold piece 27 is arranged above and below the first mold piece 25, and a fourth mold piece 28 is arranged on the left and right of the third mold piece 27. The third mold piece 27 and the left and right fourth mold pieces 28 press the second sub region 16.

As shown in FIG. 3, the first mold 20 is constructed by combining the mold pieces 25, 26, 27 and 28 described above. Comb-tooth-shaped first slide rails 31 are formed on both sides of the third mold piece 27. Fourth mold piece 2
In FIG. 8, the comb-shaped second slide rail 3 is provided at a position facing the first slide rail 31 of the third mold piece 27.
2 is formed. Both slide rails 31 and 32 are arranged in mesh with each other. In FIG. 3, the left and right second mold pieces 26 are k2 to k7 with respect to the first mold piece 25.
Bend along the line and the k3 to k6 lines. Similarly, the upper and lower third mold pieces 27 are k2 to k1 with respect to the first mold piece 25.
Bend along the k3 line and the k6 to k7 lines. The four fourth mold pieces 28 are respectively rotated clockwise from the upper left in the order of k.
It bends along each line of 1-k2, k3-k4, k5-k6, k7-k8. The fourth mold piece 28 bends in synchronization with the third mold piece 27 during press working.
That is, the pressing surfaces of the two mold pieces 27 and 28 are bent while being kept flush. Due to the bending of the second mold piece 26 and the third mold piece 27, the fourth mold piece 28 is positioned at an angular position of the first mold piece 25 (for example, the upper left fourth mold in FIG. 3). The piece 28 rotates around k2) and approaches the direction of the third mold piece 27. That is, the third meshing state
And both slide rails 31 of the fourth mold pieces 27, 28,
32 slides on each other to allow the two mold pieces 27, 28 to approach each other. In the present embodiment, the tips of both slide rails 31 and 32 are designed to abut against the opposing mold pieces 27 and 28 in a just bent state.

As shown in FIGS. 5 and 6, recesses 35 are formed in steps on the pressing surfaces of the second to fourth mold pieces 26 to 28. As shown in FIG. 3, when the recesses 35 are totalized, a holding portion 36 that matches the outer shape of the wooden thin plate 11 is formed.
Will be formed. The thin wood plate 11 is the holding portion 3
6 will be pressed in the state hold | maintained. Figure 7-
As shown in FIG. 10, the third and fourth mold pieces 27, 28
Both slide rails 31 and 32 have their pressing surfaces (PS21) at a position one step lower than the pressing surface (PS1) of the recess 35.
Therefore, when the upper first molds 20 and 21 are pressed, as shown in FIG.
The closest distance between the press surfaces PS2 at both slide rails 31 and 32 is wider than the closest distance.

Next, a manufacturing process for manufacturing such a thin wooden plate 11 by pressing with a pressing device will be described with reference to FIGS. 12 (a) to 12 (d). In the figure, the wood thin plate 11 is drawn slightly thicker than it actually is. As shown in FIG. 12A, the upper first molds 20 and 21 are attached to the pressing device. Then, the wood thin plate 11 is set on the holding portion 36 of the first mold 20. Then, the second mold 21 is lowered to fit the holding portion 36 on the second mold 21 side to the wood thin plate 11, and the wood thin plate 11 is pressed with a predetermined pressing force (FIG. 12 (b)). . In this state, the wooden thin plate 11 is held and restrained by the holding portions 36 between the upper and lower portions, and is strongly pressed up and down. However, since pressing is performed with the press surface PS1 as a reference as described above, there is some margin between the press surfaces PS2 at the positions of both slide rails 31 and 32. Therefore, the wood thin plate 11 portion pressed against the press surface PS1 is not constrained and deformed, and the triangular region Δ facing the press surface PS2 is deformed by compression. Incidentally, before the wood thin plate 11 is molded in this way, the upper first molds 20, 2
The positions of the respective mold pieces 25 to 28 of the upper first molds 20 and 21 which are simply pressing 1 are referred to as original positions. Then, FIG.
As shown in (c), the second to fourth mold pieces 26 to 28 are gradually bent from the original position. That is, the second die of the lower die 21 is maintained while the pressed state of the first die piece 25 is maintained.
~ Stand up the fourth mold pieces 26 to 28 inward,
The second to fourth mold pieces 26 to 28 of the upper mold 20 are erected outward. At this time, the second to fourth mold pieces 2
Bending is performed while maintaining the pressing force of 6 to 28. With the bending of the second to fourth mold pieces 26 to 28, the second region 13 of the wood thin plate 11 is changed to the first region 1.
Stand up for 2. Both the slide rails 31 and 32 approach each other along with the bending. The areas of the press surfaces PS2 of both slide rails 31 and 32 gradually decrease with the approach. The portion of the wooden thin plate 11 located on both slide rails 31 and 32, that is, the triangular region Δ of the second sub-region 16 is compressed as both slide rails 31 and 32 approach, and becomes the compression portion 8. This compression is realized by having a slight margin between the press surfaces PS2.

Predetermined bending state (both slide rails 3
The main body 2 of the wooden tray 1 is completed in the state where the tips of the 1, 32 are in contact with the opposing mold pieces 27, 28 in FIG. 12 (d). In this state, the pressed state by the upper first molds 20 and 21 is not yet released. Here, once, only the third and fourth mold pieces 27 and 28 are returned from the bent state to the original position. Then, the second wall plate portion 7 of the main body 2 formed from the side is exposed. The compression portion 8 is also exposed on the second wall plate portion 7. At this stage, the attachment plate 3 is attached to the second wall plate portion 7 with an adhesive, and the adhesive is held until the fixing force of the adhesive is exerted and the compression portion 8 is not likely to be restored. The pressed state by the molds 20 and 21 is completely released.

With this configuration, the first embodiment
Then, the following effects are produced. (1) The reduction amount of the area when the second region 13 of the thin wooden plate 11 is erected is concentrated in the compression portion 8 which is a part, and is fixed by the attaching plate 3 so as not to restore it, which is complicated. Therefore, it is possible to provide the wooden tray 1 in which the shape is not easily restored and a crack does not occur, regardless of the method of increasing the cost. (2) Since the fibers are compressed in a direction intersecting the length direction of the fibers, the wood fibers are less likely to be broken, and the strength of the compression portion 8 can be maintained. (3) Since the compression part 8 is hidden by the attachment plate 3, the compression part 8 is not exposed and the appearance is not damaged. Moreover, since the attachment plate 3 is a thin wooden plate having a fiber direction that intersects with the fiber direction of the second wall plate portion 7 in a direction substantially orthogonal to the fiber direction, the attaching force of the wood tray 1 in the Y-direction tearing force. It is supposed to be strengthened.

(Embodiment 2) As shown in FIG. 13, a wooden tray 1 manufactured by the method of the embodiment 2 is composed of only a main body 2 in which a thin wooden plate is compressed and deformed. The main body 2 includes a substantially rectangular bottom plate portion 5 and first and second wall plate portions 6 and 7 that surround the bottom plate portion 5 from four sides. The first wall plate portions 6 are arranged to face each other along the long side portions of the bottom plate portion 5, and the second wall plate portions 7 are arranged to face each other along the short side portions of the bottom plate portion 5. Compressed portions 8 are formed near both ends of the second wall plate portion 7. The compression part 8 is used when the first and second wall plate parts 6 and 7 are raised from the bottom plate part 5.
Is a partially compressed portion, and the first and second wall plate portions 6 and 7 are raised from the bottom plate portion 5 with an inclination according to the amount of compression. The compression section 8 is prevented from being restored by an adhesive.

Also in the second embodiment, the above-mentioned first embodiment
The wooden tray 1 is manufactured from the same thin wooden plate 11 as shown in FIG. Therefore, detailed description of the thin wood plate 11 is omitted. Further, press molding is performed by the first and second molds 20 and 21 shown in FIGS. 3 to 11 similar to the first embodiment. Therefore, detailed description of the first and second molds 20 and 21 is omitted. Based on FIGS. 12A to 12D, an outline of a manufacturing process for manufacturing such a thin wood plate 11 by pressing with a pressing device will be described.
As shown in FIG. 12A, the upper first molds 20 and 21 are attached to the pressing device. Then, the wood thin plate 11 is set on the holding portion 36 of the first mold 20. Here, when setting the thin wood plate 11, an adhesive is applied in advance to the triangular region Δ portion. Then, the second mold 21 is lowered to fit the holding portion 36 on the second mold 21 side to the wood thin plate 11, and the wood thin plate 11 is pressed with a predetermined pressing force (FIG. 12 (b)). . In this state, the wooden thin plate 11 is held and restrained by the holding portions 36 between the upper and lower portions, and is strongly pressed up and down. However, since pressing is performed with the press surface PS1 as a reference as described above, there is some margin between the press surfaces PS2 at the positions of both slide rails 31 and 32. Therefore, the wood thin plate 11 portion pressed against the press surface PS1 is not constrained and deformed, and the triangular region Δ facing the press surface PS2 is deformed by compression. It should be noted that the positions of the respective mold pieces 25 to 28 of the upper first molds 20 and 21 that are simply pressing the upper first molds 20 and 21 before molding the thin wooden plate 11 in this manner are the original positions. Say. Next, as shown in FIG. 12C, the second to fourth mold pieces 26 to 28 are gradually bent from the original position. That is, while the pressed state of the first mold piece 25 is maintained, the second to fourth mold pieces 26 to 28 of the lower mold 21 are erected toward the inside and the second to fourth molds of the upper mold 20. The mold pieces 26 to 28 are erected outward. At this time, the second to fourth mold pieces 26 to 28 are bent while maintaining the pressing force. With the bending of the second to fourth mold pieces 26 to 28, the second region 13 of the thin wooden plate 11 stands upright with respect to the first region 12. Both the slide rails 31 and 32 approach each other along with the bending. The areas of the press surfaces PS2 of both slide rails 31 and 32 gradually decrease with the approach. The part of the thin wooden plate 11 located on both slide rails 31 and 32,
That is, the triangular area Δ of the second sub area 16 is compressed as the slide rails 31 and 32 approach each other, and becomes the compression portion 8. This compression is realized by having a slight margin between the press surfaces PS2. The adhesive applied with compression penetrates into the wood fibers and firmly fixes the fibers together. The main body 2 of the wooden tray 1 in a predetermined bent state (a state in which the tips of both slide rails 31 and 32 are in contact with the opposing mold pieces 27 and 28, FIG. 12D).
Is completed. Immediately, the upper first molds 20 and 21 are released at a stage where there is no risk of restoring the compression portion 8 without releasing the pressed state by the upper first molds 20 and 21.

With this configuration, the second embodiment
Then, the following effects are produced. (1) The reduction amount of the area when the second region 13 of the thin wooden plate 11 is erected is concentrated in the compression portion 8 which is a part, and is fixed by the attaching plate 3 so as not to restore it, which is complicated. Therefore, it is possible to provide the wooden tray 1 in which the shape is not easily restored and a crack does not occur, regardless of the method of increasing the cost. (2) Since the fibers are compressed in a direction intersecting the length direction of the fibers, the wood fibers are less likely to be broken, and the strength of the compression portion 8 can be maintained. (3) It is possible to prevent the compression section 8 from being restored by previously applying an adhesive to the portion where the compression section 8 is to be formed, and it is possible to reduce the manufacturing cost because there is no extra step.

(Third Embodiment) An example of a wooden tray 1 manufactured by the method of the third embodiment is as shown in FIG. Since the description of the configuration of FIG. 14 is the same as that of the first embodiment of FIG. 1 (the area of the compression unit 8 is slightly different), the same numbers are assigned and detailed description is omitted.

Next, a method of manufacturing such a wooden tray 1 will be described. First, the thin wooden plate 11 as a raw material for the wooden tray 1 before forming will be described. As shown in FIG. 15, the wooden thin plate 11 is configured as a flat plate of a modified octagon. For convenience of explanation, numbers are sequentially assigned clockwise to each vertex of the thin wooden plate 11 with P1 at the upper left in the figure (P1 to P8). The rectangular portion surrounded by the broken line in the figure is the first region 12 which becomes the bottom plate portion 5. The vertices of the first area 12 are sequentially numbered clockwise (Q1 to Q4) with Q1 at the upper left of the drawing. A second region 13 surrounds the first region 12 in a band shape. The trapezoidal portion surrounded by P1, Q1, Q4, P8 and the trapezoidal portion surrounded by P4, Q2, Q3, P5 in the second region 13 are the portions that become the first wall plate portion 6 1 sub-region 15). Further, the deformed hexagonal portion surrounded by P1, P2, P3, P4, Q2, Q1 in the second region 13 and P5, P6, P7, P8, Q4, Q3.
The deformed hexagonal portion surrounded by is the portion that becomes the second wall plate portion 7 (this is referred to as the second sub-region 16). That is, the second area 13 is composed of the first and second sub areas 15 and 16.

In the third embodiment, as shown in FIG.
1, P2, P7, R4 surrounded by a strip, R2, P
A strip-shaped portion surrounded by 3, P6 and R3 (this is referred to as a strip-shaped region Λ) is compressed and contracted. This compression direction is performed in a direction substantially orthogonal to the length direction of the wood fiber direction. R1 to R4 are P1 to P2 and P
3 to P4, P5 to P6, and P7 to P8, which are theoretical points arranged at intermediate positions of line segments connecting the lines. The strip-shaped region Λ of the thin wooden plate 11 is formed by first and second molds 50 and 5 which will be described later.
As a result of being compressed in the preprocessing by 1, the temporary compression area ρ1 and the permanent compression area ρ2 are obtained as shown in FIG. The temporary compression area ρ1 is a portion that is restored to its original state when it finally becomes the wooden tray 1 after being compressed,
The permanent compression region ρ2 is a portion where the wooden thin plate 11 is held in a compressed state as it is when the wooden thin plate 11 finally becomes the wooden tray 1.

Next, a schematic structure of the first to third molds 50, 51 and 52 for pressing the above-mentioned wood thin plate 11 will be described. First, the first mold 50 will be described. The second mold 51 has the same shape as the pressing surface of the first mold 50. Therefore, detailed description of the second mold 51 is omitted. As shown in FIGS. 17 and 18, the first mold 5
0 is composed of three components. The drum-shaped mold piece group 55 in the center of the figure is composed of a first mold piece 56, a second mold piece 57 on the left and right of the first mold piece 56, and a connecting plate group 58 that connects both mold pieces 56, 57. There is. The first area 12
Is pressed by the first mold piece 56 and the adjacent connecting plate group 58, and the first sub-region 15 is pressed by the second mold piece 57 and the adjacent connecting plate group 58. A trapezoidal mold piece group 60 is arranged at the upper and lower positions of the drum-shaped mold piece group 55 in the figure. The trapezoidal mold piece group 60 includes a third mold piece 61, a fourth mold piece 62 on both sides of the third mold piece 61, and both mold pieces 6.
It is composed of a connecting plate group 63 for connecting 1, 62. The second sub-region 16 is pressed by the trapezoidal mold piece group 60. As shown in FIG. 19, the connecting plate groups 58 and 63 are composed of a large number of elongated metal plate members 6.
4 are connected by a connecting fitting 65 also serving as a leaf spring, which is compressible in the direction of the arrow in FIG. 19 and further has flexibility as a whole of the connecting plate groups 58, 63.
It should be noted that the illustration of the connecting fitting 65 is omitted in the drawings other than FIG.

In FIG. 17, the upper and lower trapezoidal mold piece groups 60 are bent along lines k1, k2, k3, k4 and k5, k6, k7, k8 with respect to the drum-shaped mold piece group 55. Further, in the drum-shaped mold piece group 55, the first mold piece 56 and the left and right second mold pieces 57 can be bent by utilizing the flexibility of the connecting plate group 58. Trapezoid mold piece group 6
21, the third mold piece 61 and the fourth mold pieces 6 on the left and right of the third mold piece 61 are used by utilizing the flexibility of the connecting plate group 63 as shown in FIG.
The approach with 2 can be permitted. 17 and 18
, The second to fourth mold pieces 56, 57, 61,
On the pressing surface of 62, concave portions 66 are formed in different steps. As shown in FIG. 17, when the recesses 66 are totalized, a holding portion 67 that matches the outer shape of the thin wooden plate 11 is formed. The thin wood plate 11 is pressed while being held by the holding portion 67. 20 to 22
As shown in FIG.
3 has a similar structure (not shown), but is located at a position one step lower than the pressing surface of the recess 66 (PS1), that is, the tip surface of the metal plate body 64. And) are arranged. Therefore, when the first die 50 and the second die 51 are pressed, as shown in FIGS. 21 and 22, the connecting plate group 5 is closer than the closest distance of the pressing surface PS1 at the recess 66 position.
The closest distance between the press surfaces PS2 at the 8,63 positions becomes wider. 20 to 22, the thickness of the thin wooden plate 11 is shown in a slightly exaggerated manner.

In the third embodiment, first, the above-mentioned wood thin plate 1 is used.
Pre-processing for forming a temporary compression region ρ1 and a permanent compression region ρ2 by pressing the first strip-shaped region Λ (first processing step)
Is done. This processing is performed by the first and second molds 50, 51.
Done by First, the press device (not shown)
Then, the second molds 50 and 51 are mounted. Then, the wood thin plate 11 is held by the holding portions 67 of the first and second molds 50 and 51 and pressed from above and below by the first and second molds 50 and 51 as shown in FIG. Wood thin plate 1 in this state
1 is held and restrained by the holding portion 67 between the upper and lower portions, and is strongly pressed vertically. However, since pressing is performed with the press surface PS1 as a reference as described above, there is some margin between the press surfaces PS2 at the position of the connecting plate group 58 (the connecting plate group 63 is similar although not shown). There is. Here, as shown in FIG. 22, the second mold piece 56 is compressed in the width direction (left and right direction in FIGS. 21 and 22) by a press mechanism (not shown). This compression is realized by the connection plate groups 58 and 63 contracting against the urging force of the connection fitting 64. The wood thin plate 11 on the press surface PS1 is not compressed because it is in a strong pressed state in the vertical direction, but the wood thin plate 11 has a margin in the vertical width on the press surface PS2, so the wood thin plate 11 is at the connecting plate groups 58 and 63 positions.
That is, the compressive force concentrates on the strip region Λ. That is, as shown in FIG. 16, a temporary compression region ρ1 and a permanent compression region ρ2 are formed in the strip region Λ portion.

After the completion of the above pretreatment, the second mold 51 is replaced with the third mold 52 while the first mold 50 remains as it is, and the manufacturing process (the second and third working processes) is started. . here,
The third mold 52 is a mold having a trapezoidal cross section corresponding to the shape of the inner peripheral surface of the main body 2 to be molded. 24 (a)-
Based on FIG. 24 (c), an outline of a manufacturing process for manufacturing such a thin wood plate 11 by pressing with a pressing device will be described. In the figure, the wood thin plate 11 is drawn slightly thicker than it actually is. As shown in FIG. 24 (a), the pressing device includes first and third molds 50, 5.
Wear 2. (If the pretreatment is performed as it is, the thin wooden plate 11 is compressed and set in the holding portion 67 of the first mold 50). Then, the third die 52 is lowered to press the thin wooden plate 11 with a predetermined pressing force (see FIG. 2).
4 (b)). At this time, the thin wooden plate 11 is compressed in the width direction in the state in which the upper and lower holding portions 67 are strongly pressed vertically as shown in FIG. Then, FIG.
As shown in (c), the first mold 50 gradually bends the second to fourth mold pieces 57, 61, 62 while releasing the compression in the width direction with respect to the wooden thin plate 11. These second
~ The second region 13 of the thin wooden plate 11 stands up with respect to the first region 12 as the fourth mold pieces 57, 61, 62 are bent. In this way, the wooden tray 1 having the structure shown in FIG. 25 can be obtained.

Since the first mold 50 releases the compression in the width direction as the thin wood plate 11 bends, the temporary compression region ρ1 and the permanent compression region ρ2 have their own restoring force (a kind of reaction against the compressing force). Force) to return to the state of the strip region Λ. At this time, the temporary compression area ρ1 is restored, but the permanent compression area ρ2 is changed to the second area 13 (second
As the sub-region 16) of the first metal mold 50 is compressed, the connecting metal fitting 64 is compressed as shown in FIG.
The compression portion 8 is formed without being canceled by the cancellation of the compression of 1. The main body 2 of the wooden tray 1 is completed in the folded state shown in FIG. In this state, the pressed state by the first and third molds 50 and 52 is not yet released. Here, only the third and fourth mold pieces 61 and 62 are once returned from the bent state to the original position. Then, the second wall plate portion 7 of the main body 2 formed from the side is exposed. The compression portion 8 is also exposed on the second wall plate portion 7. At this stage, the attachment plate 3 is attached to the second wall plate portion 7 with an adhesive.
It is held until the fixing force of the adhesive is exerted and there is no possibility of the compression section 8 being restored, and then the pressed state by the first and third molds 50 and 52 is completely released again.

With this structure, the third embodiment
Then, the following effects are produced. (1) The reduction amount of the area when the second region 13 of the thin wooden plate 11 is erected is concentrated in the compression portion 8 which is a part, and is fixed by the attaching plate 3 so as not to restore it, which is complicated. Therefore, it is possible to provide the wooden tray 1 in which the shape is not easily restored and a crack does not occur, regardless of the method of increasing the cost. (2) Since the fibers are compressed in a direction intersecting the length direction of the fibers, the wood fibers are less likely to be broken, and the strength of the compression portion 8 can be maintained. (3) Since the compression part 8 is hidden by the attachment plate 3, the compression part 8 is not exposed and the appearance is not damaged. Moreover, since the attachment plate 3 is a thin wooden plate having a fiber direction that intersects with the fiber direction of the second wall plate portion 7 in a direction substantially orthogonal to the fiber direction, the attaching force of the wood tray 1 in the Y-direction tearing force. It is supposed to be strengthened.

The present invention can be modified and embodied as follows. The attachment plate 3 may cover only the compression portion 8 instead of the entire second side wall plate portion 7. The attachment plate 3 was attached in a direction substantially orthogonal to the fiber direction of the main body 2. This is because the strength is improved in that case. However, it is not particularly limited to the substantially orthogonal direction. -The attachment plate 3 need not be made of wood. The adhesive used in each of the above embodiments is an instant adhesive, but other adhesives may be used. Also,
From the viewpoint of environmental protection, biodegradable adhesives are preferable. In the above-described first and third embodiments, the mold piece is partially returned to the original position to expose the surface on which the compression portion 8 is formed, and the attachment plate 3 is attached. However, even if this is not done, for example, 1) at the time of pressing, the wood thin plate 11 is sandwiched from above and below by a support plate (for example, an iron plate), and this support plate is also molded. In this way, the shape of the pressed state can be maintained even if the mold is released, so that the attachment plate 3 is attached here. 2) Since the compression part 8 does not recover for a short time, the mold is released, the main body 2 is taken out, the sticking plate 3 is quickly stuck, and the clamp does not restore it (especially the compression part 8 is the center). . The position of the compression unit 8 is not limited to the position in each of the above embodiments. In short, the surplus portion when the second region 13 of the thin wooden plate 11 is erected may be concentrated in a part and compressed. The shape of the thin wood plate 11 is not limited to the above-mentioned respective embodiments. -It is not limited to a rectangular wooden tray. In addition, it is free to implement in a modified mode without departing from the spirit of the present invention.

Other technical ideas that can be grasped from the above-described embodiment in order to achieve the object of the present invention will be described below as supplementary notes. (1) The restoration prevention process is to apply an adhesive to a part of the second region that becomes the compression section before the compression processing of the compression section. Tray manufacturing method. (2) The method for manufacturing a wooden tray according to any one of claims 1 to 5 or appendix 1, wherein the front compression part is a triangular part having an apex at the intersection of the bottom plate part and the wall plate part. (3) The wood thin plate is sandwiched between the first and second molds, and the pressing surfaces of the two molds are configured such that the compressed portion is wider than the uncompressed portion and the uncompressed portion is constrained. The method for producing a wooden tray according to any one of claims 1 to 5 or claim 1 or 2, wherein

[0032]

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a wooden tray according to a first embodiment.

FIG. 2 is a plan view of the thin wood plates according to the first and second embodiments.

FIG. 3 is a plan view of the first mold according to the first and second embodiments.

FIG. 4 is an exploded plan view of the mold shown in FIG.

5 is a cross-sectional view taken along the line AA of the mold shown in FIG.

6 is a cross-sectional view of the mold of FIG. 3 taken along the line BB.

FIG. 7 is a cross-sectional view taken along the line CC of the mold shown in FIG.

FIG. 8 is a cross-sectional view taken along the line D-D of the mold shown in FIG.

FIG. 9 is a cross-sectional view taken along the line EE of the mold shown in FIG.

10 is a cross-sectional view of the mold of FIG. 4 taken along the line FF.

FIG. 11 shows the first and second embodiments of the first and second embodiments.
Explanatory drawing of a state in which a wood thin plate is pressed by the mold of FIG.

12A to 12D are explanatory views for explaining the outline of the manufacturing process of the wooden tray in the first and second embodiments.

FIG. 13 is a perspective view of the wooden tray according to the second embodiment.

FIG. 14 is an exploded perspective view of the wooden tray according to the third embodiment.

FIG. 15 is a plan view of a thin wood plate according to the third embodiment.

FIG. 16 is a plan view showing a state in which the thin wooden plate according to the third embodiment is compressed in the width direction.

FIG. 17 is a plan view of a first mold according to the third embodiment.

18 is an exploded plan view of the mold shown in FIG.

FIG. 19 is an enlarged side view showing a part of the connection plate group according to the third embodiment.

20 is a cross-sectional view taken along the line GG of the mold shown in FIG.

FIG. 21 is a cross-sectional view illustrating a state where a thin wooden plate is sandwiched between first and third molds in the third embodiment.

22 is a cross-sectional view illustrating a state in which the thin wooden plate is compressed in the width direction in FIG. 21.

FIG. 23 is an enlarged view of the vicinity of a connecting plate group that connects the third and fourth mold pieces according to the third embodiment.

24 (a) to 24 (d) are explanatory views for explaining the outline of the manufacturing process of the wooden tray in the third embodiment.

FIG. 25 is a plan view of the wooden tray according to the third embodiment.

[Explanation of symbols]

3 ... a sticking plate as a restoration preventing process, 5 ... a bottom plate part,
6, 7 ... Wall plate part, 8 ... Compression part, 11 ... Wood thin plate, 12 ...
1st area | region, 13 ... 2nd area, (triangle | delta) area | region as delta ... compression area, ρ1 ... temporary compression area, ρ2 ... permanent compression area.

Claims (5)

[Claims] 1. A flat plate-like wood thin plate having a first region serving as a bottom plate portion and a second region disposed around the first region and serving as a wall plate portion is pressed to form a bottom plate portion. A method of manufacturing a wooden tray configured to obtain a wooden tray including a wall plate portion surrounding the bottom plate portion, wherein a constraining region in which a part of the second region is a compression region and the other parts are not compressed And the second area is the same as the first area.
At the same time as standing up in either the front or back direction with respect to the area, the excess area generated by standing up is absorbed by compressing the compressed area in the width direction to form a compressed portion, and then the compressed portion is restored. A method for manufacturing a wooden tray, characterized in that a restoration preventing treatment is applied so as not to do so. 2. A flat plate-like wood thin plate having a first region which serves as a bottom plate portion and a second region which is arranged around the first region and serves as a wall plate portion is pressed to form a bottom plate portion. In a method of manufacturing a wooden tray configured to obtain a wooden tray constituted by a wall plate portion surrounding the same bottom plate portion, at least a part of the second area is set as a first compression area and the other portion is A first constraining region that is not compressed and that compresses the first compressing region in the width direction to form a temporary compressing part and a permanent compressing part arranged at a predetermined position in the second region.
And the wall plate portion is erected with respect to the bottom plate portion, and at the same time the temporary compression portion of the first compression region formed by the first processing step is restored, A second processing step in which the excess area generated in the region is absorbed by not restoring the permanent compression section, and the permanent compression section does not restore to the wood thin plate processed by the second processing step. A method of manufacturing a wooden tray, characterized in that it has a third processing step for carrying out restoration prevention processing as described above. 3. The wooden tray according to claim 1 or 2, wherein the restoration prevention treatment is to attach a flat thin plate on the compressed portion so as to cover the compressed portion after forming the compressed portion. Production method. 4. The bottom plate portion has a rectangular shape, and the bottom plate portion is surrounded by four long wall plate portions from four sides, and the compression portion is located near a corner of a pair of opposing same wall plate portions. The wooden tray manufacturing method according to claim 1, wherein the wooden tray is provided. 5. The method of manufacturing a wooden tray according to claim 1, wherein the compression section is compressed in a direction intersecting the fiber direction.