Corrugated cardboard plywood and storage box

Abstract

To provide a technology to ensure strength of a corrugated cardboard plate material.SOLUTION: A first aspect of the technology disclosed herein relates to a corrugated cardboard plywood. The corrugated cardboard plywood comprises a corrugated cardboard plate-like core material and a corrugated cardboard outside material. The outside material comprises a first plate-like part covering a first surface of the core material, a second plate-like part covering a second surface opposite to the first surface of the core material, and a connection part that connects the first plate-like part and the second plate-like part. The connection part is connected with the first plate-like part via a first folding line and connected with the second plate-like part via a second folding line, and may overlap a peripheral edge between the first surface and the second surface of the core material.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This specification discloses technology relating to corrugated board plywood and containers. [Background technology]

[0002] Patent Document 1 discloses a storage shelf using corrugated cardboard sheets. The storage shelf is formed by assembling a plurality of packaging boxes. The packaging boxes are made by folding the corrugated cardboard sheets. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-004068 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above technology, a window frame is formed at the front opening in order to ensure the strength of the packaging box. In this configuration, the opening area of ​​the packaging box is narrowed, making it difficult to put in and take out the target object.

[0005] This specification provides a technique for ensuring the strength of corrugated cardboard boards. [Means for solving the problem]

[0006] A first aspect of the technology disclosed in this specification relates to a corrugated cardboard plywood. The corrugated cardboard plywood includes a plate-shaped core material made of corrugated cardboard and an outer material made of corrugated cardboard, and the outer material includes a first plate-shaped portion covering a first surface of the core material, a second plate-shaped portion covering a second surface of the core material opposite to the first surface, and a connecting portion connecting the first plate-shaped portion and the second plate-shaped portion, and the connecting portion is connected to the first plate-shaped portion via a first fold line and to the second plate-shaped portion via a second fold line, and may overlap a peripheral portion between the first surface and the second surface of the core material.

[0007] In this configuration, the outer materials are laminated on both surfaces of the core material. With this configuration, the strength of the plywood can be ensured by arranging multiple corrugated board sheets in layers. In addition, the outer materials are integrally formed by connecting the first plate-shaped portion and the second plate-shaped portion with the connecting portion, and sandwich the core material. With this configuration, it is possible to prevent the core material and the outer materials from being separated.

[0008] In a second aspect, in the first aspect described above, a through hole is provided that penetrates the core material and the outer material, and the inner surface of the through hole may have a portion that extends at an angle with respect to at least the first grain direction and the second grain direction.

[0009] According to this configuration, the central core of at least one of the core material and the outer material, i.e., the corrugated cross section of the so-called flutes, can be exposed to the inner peripheral surface of the through hole, which increases the friction coefficient of the inner peripheral surface, making it difficult for the fitting piece or the like inserted into the through hole to come out.

[0010] In a third aspect, in the first or second aspect, the outer material may be made of cardboard that is thinner than the core material.

[0011] By making the core material thick while making the outer materials thin, it is possible to easily form fold lines in the outer materials while maintaining the strength of the plywood.

[0012] In a fourth aspect, in any one of the first to third aspects, the first fold line and the second fold line may be arranged in a first grain direction of a step of a core of the outer material.

[0013] According to this configuration, the fold lines of the outer material can be formed along the grain direction of the corrugated board, which makes it easier to form the fold lines compared to a configuration in which the fold lines are arranged at an angle toward the grain direction.

[0014] In a fifth aspect, in any one of the first to fourth aspects above, a first grain direction of the grain of the core of the outer material and a second grain direction of the grain of the core of the core material may be consistent.

[0015] With this configuration, by aligning the grain direction of the core material and the outer material, the strength of the plywood can be increased against a load along the grain direction.

[0016] A sixth aspect of the technology disclosed in this specification relates to an assembly. The assembly is produced by assembling a plurality of plate materials, and at least one plate among the plurality of plate materials may be the corrugated plywood of any one of the above first to fifth aspects.

[0017] According to this configuration, the board material used for the storage device can be corrugated cardboard plywood with ensured strength, thereby preventing the strength of the storage device from being reduced by the corrugated cardboard.

[0018] In a seventh aspect, in the sixth aspect above, a specific board among the plurality of boards is a corrugated board of any one of the first to fifth aspects above, and the specific side board has a through hole penetrating the core material and the outer material, and the inner surface of the through hole has a portion extending at an angle with respect to at least one of a first grain direction of the rows of the core of the outer material and a second grain direction of the rows of the core of the core material, and a board among the plurality of boards different from the specific board may have a fitting piece that fits into the through hole.

[0019] According to this configuration, the central core of at least one of the core material and the outer material, i.e., the corrugated cross section of the so-called flutes, can be exposed to the inner peripheral surface of the through hole, which increases the friction coefficient of the inner peripheral surface, making it difficult for the fitting piece inserted into the through hole to come out. [Brief description of the drawings]

[0020] [Figure 1] FIG. 2 is a front perspective view of the storage device of the embodiment. [Diagram 2]FIG. 2 is a rear perspective view of the storage device of the embodiment. [Diagram 3] 1 shows a plan view of the core material of the bottom plate of the embodiment. [Figure 4] 1 shows an exploded view of the outer material of the bottom plate of the embodiment. [Diagram 5] FIG. 2 is an exploded perspective view for explaining the structure of the bottom plate of the embodiment. [Figure 6] 1 shows a plan view of the core material of the left and right side panels of the embodiment. [Figure 7] 1 shows an exploded view of the outer members of the left and right side panels of the embodiment. [Figure 8] FIG. 2 shows a front view of the back plate of the embodiment. [Figure 9] 9 shows an enlarged perspective view of region IX in FIG. 8. [Figure 10] 2 shows an enlarged perspective view of region X in FIG. 1. [Figure 11] FIG. 2 is a front perspective view of the storage shelf of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] As shown in FIG. 1, the storage device 10 is a storage shelf with an opening on the front. As shown in FIG. 11, it is possible to stack a plurality of storage devices 10 vertically to create a storage shelf with shelves of a plurality of heights. The storage device 10 is not limited to a storage shelf, and may be a storage box or the like with an opening on the upper end. The storage device 10 may also be provided with a lid for closing the opening. The front-rear, left-right, and up-down directions included in this specification are defined for ease of explanation, and do not necessarily define the posture during actual use.

[0022] The storage device 10 includes a bottom panel 12, a back panel 14, a left panel 16, a right panel 18, and a top panel 20. As shown in FIG. 2, the back panel 14 forms the rear end surface of the storage device 10. As shown in FIG. 8, the back panel 14 is made of a single piece of cardboard 22. As shown in FIG. 9, the cardboard 22 of the back panel 14 includes liners 24, 26 and multiple cores 28a, 28b, 28c. Each of the liners 24, 26 has a planar shape and is disposed on the front and back surfaces of the cardboard 22. Note that the thicknesses of the liners 24, 26 and the cores 28a, 28b, 28c are omitted in FIG. 9.

[0023] A plurality of cores 28a, 28b, 28c are disposed between the liners 24, 26. In the cores 28a, 28c, corrugations extending parallel to the vertical direction are continuously arranged in the horizontal direction. That is, the grain direction D1 of the back panel 14 is parallel to the vertical direction. A flat core 28b is disposed between the cores 28a, 28c. The corrugated cardboard 22 is so-called W-corrugated (or W-flute). The height H1 of the corrugation of the core 28a is lower than the height H2 of the corrugation of the core 28c.

[0024] As shown in FIG. 8, the back panel 14 includes a main body 14m, four through holes 14a, 14a, 14b, 14b, and four fitting pieces 14c, 14c, 14d, 14d. The main body 14m has a rectangular flat plate shape. The two through holes 14a, 14a are formed by penetrating the back panel 14 slightly below the upper edge 14U of the main body 14m. The two through holes 14a, 14a are arranged spaced apart from each other in the left-right direction. The through hole 14a has a rectangular shape with long sides parallel to the left-right direction. The length of the through hole 14a in the up-down direction is slightly shorter than the thickness of the top panel 20. As shown in FIG. 9, the lower edge 30 of the inner peripheral surface of the through hole 14a is inclined perpendicular to the grain direction D1 of the back panel 14. The lower edge 30 exposes a cross section perpendicular to the corrugated shape of the cores 28a, 28b, 28c. At the upper edge of the through hole 14a, similar to the lower edge 30, the cross section perpendicular to the wave shape of the cores 28a, 28b, and 28c is exposed.

[0025] As shown in FIG. 8, the two through holes 14b, 14b are formed through the back plate 14 slightly above the lower edge of the back plate 14. The two through holes 14b, 14b are arranged spaced apart from each other in the left-right direction. The two through holes 14b, 14b are arranged at the same positions as the two through holes 14a, 14a in the left-right direction. The through hole 14b has the same shape as the through hole 14a. At the upper and lower edges of the inner circumferential surface of the through hole 14b, cross sections perpendicular to the corrugated shape of the cores 28a, 28c are exposed.

[0026] The two mating pieces 14c, 14c protrude leftward from the left edge 14L of the main body 14m. The two mating pieces 14c, 14c are arranged spaced apart from each other in the front-rear direction. The mating piece 14c has a rectangular parallelepiped shape. The two mating pieces 14d, 14d protrude rightward from the right edge 14R of the main body 14m. In the front-rear direction, each of the two mating pieces 14d, 14d is arranged at the same position as each of the two mating pieces 14c, 14c. The mating piece 14d has the same shape as the mating piece 14c.

[0027] The bottom plate 12 is composed of a core material 40 (see FIG. 3) and an outer material 42 (see FIG. 4). As shown in FIG. 3, the core material 40 is made of the same corrugated cardboard as the corrugated cardboard 22. The grain direction D2 of the core material 40 extends parallel to the left-right direction.

[0028] The core material 40 includes a rectangular main body 40m and six mating pieces 40a, 40a, 40b, 40b, 40c, 40c. The two mating pieces 40a, 40a protrude leftward from the left end edge 40L of the main body 40m. The two mating pieces 40a, 40a are arranged spaced apart from each other in the front-rear direction. The mating piece 40a has a rectangular parallelepiped shape. The length of the mating piece 40a in the left-right direction is slightly longer than the thickness of the left side plate 16. The two mating pieces 40b, 40b protrude rearward from the rear end edge 40B of the main body 40m. The two mating pieces 40b, 40b are arranged at positions where they are inserted into the two through holes 14b, 14b. The mating piece 40b has a left-right length slightly longer than the through hole 14b. The length of the mating piece 40b in the front-rear direction is slightly longer than the thickness of the back plate 14. The two mating pieces 40c, 40c protrude to the right from the right end edge 40R of the main body 40m. In the front-rear direction, the two mating pieces 40c, 40c are disposed at the same positions as the two mating pieces 40a, 40a. The mating piece 40c has the same shape as the mating piece 40a.

[0029] As shown in Fig. 4, the outer material 42 includes plate-like portions 52, 54 and a connecting portion 56. The outer material 42 is made of a single sheet of corrugated cardboard 50. The corrugated cardboard 50 has a pair of liners and a corrugated core disposed between the pair of liners. The corrugated cardboard 50 is thinner than the corrugated cardboard 22. The corrugated cardboard 50 is, for example, an E-corrugated (i.e., E-flute) cardboard with a core height of 1.10 to 1.15 mm.

[0030] The grain direction D3 of the outer material 42 is parallel to the left-right direction, similar to the grain direction D2 of the core material 40. The plate-like portion 52 overlaps the upper surface of the core material 40. The plate-like portion 52 includes a main body 52m overlapping the main body 40m, and six fitting pieces 52a, 52a, 52b, 52b, 52c, 52c overlapping the six fitting pieces 40a, 40a, 40b, 40b, 40c, 40c. The main body 52m has a length in the front-rear direction that is slightly longer than the main body 40m, and a length in the left-right direction that is the same as that of the main body 40m. The fitting pieces 52a, 52a, 52b, 52b, 52c, 52c have the same shapes in the front-rear direction and the left-right direction as the fitting pieces 40a, 40a, 40b, 40b, 40c, 40c, respectively.

[0031] The plate-shaped portion 54 overlaps the lower surface of the core material 40. The plate-shaped portion 54 includes a main body 54m that overlaps the main body 40m, and six fitting pieces 54a, 54a, 54b, 54b, 54c, 54c that overlap the six fitting pieces 40a, 40a, 40b, 40b, 40c, 40c. The main body 54m has the same shape as the main body 52m. The fitting pieces 54a, 54a, 54b, 54b, 54c, 54c have the same shapes as the fitting pieces 52a, 52a, 52b, 52b, 52c, 52c, respectively.

[0032] A connecting portion 56 is disposed between the plate-like portions 52, 54, and is connected to the plate-like portions 52, 54 via folding lines 60, 62. The connecting portion 56 has the same length as the base portion 41 in the left-right direction. The connecting portion 56 is slightly longer than the thickness of the core material 40 in the up-down direction.

[0033] As shown in FIG. 5, the bottom plate 12 is formed by placing the core material 40 on the plate-shaped portion 52 and folding the folding lines 60 and 62 to overlap the plate-shaped portion 54 on the core material 40. That is, the bottom plate 12 has the plate-shaped portion 52, the core material 40, and the plate-shaped portion 54 overlapping each other. The connecting portion 56 overlaps the front edge of the core material 40 to completely cover the front edge. As shown in FIG. 1 and FIG. 2, the bottom plate 12 has two mating pieces 12a in which the mating pieces 40a, 52a, and 54a overlap, two mating pieces 12b in which the mating pieces 40b, 52b, and 54b overlap, and two mating pieces 12c in which the mating pieces 40c, 52c, and 54c overlap.

[0034] When the outer material 42 is folded and layered on the core material 40, taking into account the thickness of the outer material 42, the connecting portion 56 is set to be slightly longer than the thickness of the core material 40 in the vertical direction, and the main bodies 52m, 54m are set to be slightly longer than the main body 40m in the front-to-back direction.

[0035] The top plate 20 has the same shape as the bottom plate 12. The top plate 20 includes mating pieces 20a, 20a, 20b, 20b, 20c, and 20c similar to the mating pieces 12a, 12a, 12b, 12b, 12c, and 12c.

[0036] The left side panel 16 is composed of a core material 70 (see FIG. 6) and an outer material 72 (see FIG. 7). As shown in FIG. 6, the core material 70 is made of the same corrugated cardboard as the corrugated cardboard 22. The grain direction D4 of the core material 70 extends parallel to the up-down direction.

[0037] The core material 70 has a rectangular shape. The core material 70 has six through holes 70a, 70a, 70b, 70b, and 70c, 70c. The two through holes 70a, 70a penetrate the core material 70 slightly above the lower end edge 70L of the core material 70. The two through holes 70a, 70a are arranged spaced apart from each other in the front-rear direction. The through hole 70a has a rectangular shape with long sides parallel to the front-rear direction. The vertical length of the through hole 70a is slightly shorter than the thickness of the bottom plate 12. The through hole 70a has a front-rear length slightly shorter than the fitting piece 12a.

[0038] The two through holes 70b, 70b penetrate the core material 70 slightly below the upper edge 70U of the core material 70. The two through holes 70b, 70b are arranged at the same positions as the two through holes 70a, 70a in the front-rear direction. The through hole 70b has the same shape as the through hole 70a. As shown in FIG. 10, the lower edge 80 of the inner circumferential surface of the through hole 70b is inclined perpendicularly to the grain direction D4 of the core material 70. At the lower edge 80, a cross section perpendicular to the corrugated shape of the core of the core material 70 is exposed. At the upper edge of the through hole 70b, a cross section perpendicular to the corrugated shape of the core is exposed, similar to the lower edge 80. At the upper and lower edges of the through hole 70a, a cross section perpendicular to the corrugated shape of the core is exposed, similar to the lower edge 80.

[0039] The two through holes 70c, 70c penetrate the core material 70 slightly forward of the rear end edge 70B of the core material 70. The two through holes 70c, 70c are arranged spaced apart from each other in the up-down direction. The through hole 70c has a rectangular shape with long sides parallel to the up-down direction. The through hole 70a has a length in the up-down direction, the length in the front-rear direction, and the length in the left-right direction that are slightly shorter than those of the fitting piece 12c.

[0040] 7, the outer material 72 includes plate-like portions 74, 76 and a connecting portion 78. The outer material 72 is made of a single sheet of corrugated cardboard 90. The corrugated cardboard 90 has the same structure as the corrugated cardboard 50.

[0041] The grain direction D5 of the outer material 72 is parallel to the up-down direction, similar to the grain direction D4 of the core material 70. The plate-shaped portion 74 overlaps one surface of the core material 70. The plate-shaped portion 74 has a length in the front-rear direction that is slightly longer than that of the core material 70, and a length in the up-down direction that is the same as that of the core material 70. The plate-shaped portion 74 has six through holes 70a, 70a, 70b, 70b, and six through holes 74a, 74a, 74b, 74b, 74c, 74c that overlap with the six through holes 70a, 70a, 70b, 70b, and the six through holes 74a, 74a, 74b, 74b, 74c, 74c that overlap with the six through holes 70c, 70c. The through holes 74a, 74a, 74b, 74b, 74c, 74c have the same shapes in the front-rear direction and the up-down direction as the through holes 70a, 70a, 70b, 70b, and the six through holes 70c, 70c, respectively.

[0042] The plate-shaped portion 76 overlaps the other surface of the core material 70. The plate-shaped portion 76 has a similar configuration to the plate-shaped portion 74. The plate-shaped portion 76 has six through holes 76a, 76a, 76b, 76b, 76c, 76c similar to the six through holes 74a, 74a, 74b, 74b, 74c, 74c. As shown in FIG. 10, the lower edges of the inner peripheral surfaces of the through holes 74b, 76b are inclined in a direction perpendicular to the grain direction D5 of the outer material 72. At the lower edges, a cross section perpendicular to the corrugated shape of the central core of the core material 70 is exposed. Similarly, at the upper edges of the through holes 74b, 76b, a cross section perpendicular to the corrugated shape of the central core is exposed.

[0043] A connecting portion 78 is disposed between the plate-like portions 74, 76, and is connected to the plate-like portions 74, 76 via folding lines 81, 82. The connecting portion 78 has the same length as the core material 70 in the up-down direction. The connecting portion 78 is slightly longer than the thickness of the core material 70 in the left-right direction.

[0044] The left side plate 16 is produced, similarly to the bottom plate 12, by bending the outer material 72 along fold lines 81, 82 and sandwiching the core material 70 between the plate-like portions 74, 76. That is, the left side plate 16 is constructed by overlapping the plate-like portion 74, the core material 70, and the plate-like portion 76. The connecting portion 78 overlaps with the front edge of the core material 70 and completely covers the front edge.

[0045] The left side plate 16 has two through holes 16a, which are overlapped by through holes 70a, 74a, and 76a, two through holes 16b, which are overlapped by through holes 70b, 74b, and 76b, and two through holes 16c, which are overlapped by through holes 70c, 74c, and 76c. The right side plate 18 has the same shape as the left side plate 16. The right side plate 18 has through holes 18a, 18a similar to the through holes 16a, 16a, through holes 18b, 18b similar to the through holes 16b, 16b, and through holes 18c, 18c similar to the through holes 16c, 16c. As shown in FIG. 10, the through hole 16b exposes a cross section perpendicular to the corrugated shape of the central core of the core material 70 and the outer material 72. The same is true for the through holes 16a, 18a, and 18b.

[0046] (How to assemble the storage device) To assemble the storage device 10, the fitting pieces 12a, 12a of the bottom plate 12 are inserted into the through holes 16a, 16a of the left side plate 16, the fitting pieces 12c, 12c of the bottom plate 12 are inserted into the through holes 18a, 18a of the right side plate 18, and the fitting pieces 12b, 12b of the bottom plate 12 are inserted into the through holes 14b, 14b of the back plate 14. Similarly, the fitting pieces 20a, 20a of the top plate 20 are inserted into the through holes 16b, 16b of the left side plate 16, the fitting pieces 20c, 20c of the top plate 20 are inserted into the through holes 18b, 18b of the right side plate 18, and the fitting pieces 20b, 20b of the top plate 20 are inserted into the through holes 14a, 14a of the back plate 14. Furthermore, the fitting pieces 14c, 14c of the back panel 14 are inserted into the through holes 16c, 16c of the left side panel 16, and the fitting pieces 14d, 14d of the back panel 14 are inserted into the through holes 18c, 18c of the right side panel 18.

[0047] (effect) Each fitting piece is made slightly larger than the through hole that receives the fitting piece. This makes it possible to prevent the fitting piece from slipping out of the through hole. The corrugated cross section of the core is exposed at the portion of the inner peripheral surface of each through hole that is located on the long side. In this configuration, the frictional force between the fitting piece and the inner peripheral surface of the through hole can be increased by increasing the line length of the core that contacts the fitting piece that is fitted into the through hole. This makes it possible to more firmly prevent the fitting piece from slipping out of the through hole.

[0048] The mating pieces 12c, 14d, and 20c protrude rightward from the right side plate 18. Similarly, the mating pieces 12a, 14c, and 20a protrude leftward from the left side plate 16. The mating pieces 12b and 20b protrude rearward from the back plate 14. With this configuration, even if each mating piece is slightly misaligned from the through hole, it is possible to prevent the mating pieces from coming out of the through hole.

[0049] Each through hole is disposed inside the edge of the plate, whereby the fitting pieces come into contact with the inner periphery of the through hole all the way around, thereby preventing the fitting pieces from coming out of the through hole.

[0050] The bottom plate 12 is made up of a core material 40 and an outer material 42 stacked together. With this configuration, the strength of the bottom plate 12 can be ensured by stacking multiple sheets of corrugated cardboard. Furthermore, the outer material 42 is integrally formed with the plate-shaped portion 52 and the plate-shaped portion 54 connected by the connecting portion 56, and sandwiches the core material 40. With this configuration, it is possible to prevent the core material 40 and the outer material 42 from being separated. The same applies to the left and right side panels 16, 18 and the top plate 20.

[0051] By making the core material 40 thick and the outer material 42 thin, it is possible to easily form the fold lines 60, 62 in the outer material 42 while ensuring the strength of the bottom plate 12. The same is true for the left and right side plates 16, 18 and the top plate 20.

[0052] The fold lines 60, 62 of the outer material 42 can be formed parallel to the grain direction D3 of the cardboard 50. This makes it easier to form the fold lines 60, 62 compared to a configuration in which the fold lines 60, 62 are arranged at an angle to the grain direction D3. The same applies to the left and right side panels 16, 18 and the top panel 20.

[0053] By aligning the grain directions D2, D3 of the core material 40 and the outer material 42, the strength of the plywood against loads along the grain directions D2, D3 can be increased. Also, by arranging the grain directions D2, D3 parallel to the left-right direction, which is the longitudinal direction of the bottom plate 12, bending of the bottom plate 12 at a midpoint in the left-right direction can be prevented. The same applies to the top plate 20. In the left and right side panels 16, 18, by arranging the grain direction D4 of the core material 70 and the grain direction D5 of the outer material 72 parallel to the up-down direction, strength against loads in the up-down direction can be ensured.

[0054] In addition, by bending the outer member 42, it is possible to increase the rigidity of the outer member 42. The same applies to the outer plates of the left and right side plates 16, 18 and the top plate 20.

[0055] In the storage device 10, the connecting portion 56 of the outer material 42 is disposed on the front side of the bottom plate 12, and the core material 40 is not exposed. This enhances the aesthetic appeal of the bottom plate 12. The same applies to the left and right side plates 16, 18 and the top plate 20. As a result, the aesthetic appeal of the storage device 10 can be enhanced.

[0056] As shown in FIG. 10, the upper edge 16U of the left side panel 16 extends perpendicular to the grain directions D4 and D5 of the core material 70 and the outer material 72. The upper edge 16U exposes a cross section perpendicular to the corrugated shape of the core of the core material 70 and the outer material 72. The lower edge 16L of the left side panel 16 is similar. As a result, when the storage devices 10 are stacked vertically, the upper edge 16U of the left side panel 16 of the lower storage device 10 comes into contact with the lower edge 16L of the left side panel 16 of the upper storage device 10, and the high frictional force prevents the storage devices 10 stacked vertically from shifting from one to the other. The same is true for the right side panel 18. The back panel 14 also has a similar effect due to the exposure of a cross section perpendicular to the corrugated shape of the cores 28a and 28c.

[0057] Although the embodiments of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples exemplified above.

[0058] The shapes of the bottom panel 12, the back panel 14, the left and right side panels 16, 18, and the top panel 20 may be appropriately changed to match the shape of the storage device 10. For each of the bottom panel 12, the back panel 14, the left and right side panels 16, 18, and the top panel 20, corrugated plywood having a core material 40 and an outer material 42 may be used according to the desired strength, or a corrugated sheet made of one or more overlapping pieces of corrugated board may be used.

[0059] The structure and thickness of the cardboard may be the same or different for each of the bottom panel 12, left and right side panels 16, 18, and top panel 20. They may be changed depending on the desired strength, thickness, configuration, etc.

[0060] In the outer material 42, the fold lines 60, 62 are arranged parallel to the grain direction D3 of the outer material 42. However, the fold lines 60, 62 may be inclined to the grain direction D3. For example, when the outer material 42 has a large plate thickness (e.g., B stage (i.e., B flute), i.e., plate thickness of 3 mm or more), the fold lines 60, 62 may be inclined perpendicular to the grain direction D3.

[0061] In the bottom plate 12, the grain directions D2, D3 of the core material 40 and the outer material 42 do not have to be arranged parallel to each other. For example, the grain direction D2 may be inclined perpendicularly to the grain direction D3.

[0062] In the above embodiment, the storage device 10 is an example of an "assembly". The "assembly" is not limited to the storage device 10m. For example, the "assembly" may be furniture such as a desk, a table, a chair, a bed, or a sofa frame. In this case, the "assembly" may include at least one piece of corrugated plywood similar to the bottom plate 12.

[0063] In addition, the technical elements described in this specification or drawings exert technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technologies exemplified in this specification or drawings achieve multiple objectives simultaneously, and achieving one of those objectives is itself technically useful. [Explanation of symbols]

[0064] 10: storage device, 12: bottom plate, 14: back plate, 16: left side plate, 18: right side plate, 20: top plate, 22: cardboard, 28a, 28b, 28c: core, 40, 70: core material, 42, 72: outer material, 52, 54, 74, 76: plate-shaped portion, 56, 78: connecting portion, 60, 62: folding line

Claims

1. A cardboard core material, and an outer material made of corrugated cardboard; The outer material is A first plate-shaped portion covering a first surface of the core material; A second plate-shaped portion covering a second surface of the core material opposite to the first surface; a connecting portion that connects the first plate-shaped portion and the second plate-shaped portion, The connecting portion is The first plate-shaped portion is connected to the first fold line, The second plate-shaped portion is connected to the second plate-shaped portion via a second fold line, a corrugated plywood layer overlapping a peripheral edge portion of the core between the first surface and the second surface;

2. A through hole is provided through the core material and the outer material, 2. The corrugated board plywood according to claim 1, wherein the inner peripheral surface of the through hole has a portion extending at an angle with respect to at least one of a first grain direction of the corrugations of the core of the outer material and a second grain direction of the corrugations of the core of the core material.

3. 2. The corrugated board plywood of claim 1, wherein the outer material is made of corrugated board that is thinner than the core material.

4. The corrugated board plywood according to claim 1 or 2, wherein the first fold line and the second fold line are arranged in a first grain direction of the corrugations of the core of the outer material.

5. 3. The corrugated board plyboard according to claim 1, wherein a first grain direction of the corrugations of the core of the outer material coincides with a second grain direction of the corrugations of the core of the core material.

6. An assembly produced by assembling a plurality of plate materials, 3. An assembly, wherein at least one of the plurality of boards is the corrugated board according to claim 1 or 2.

7. A specific board material among the plurality of board materials is the corrugated board plywood according to claim 1 or 2, The specific side plate has a through hole penetrating the core material and the outer material, The inner peripheral surface of the through hole has a portion extending at an angle with respect to at least one of a first grain direction of the steps of the core of the outer material and a second grain direction of the steps of the core of the core material, The storage device according to claim 6 , wherein a plate material other than the specific plate material among the plurality of plate materials has a fitting piece that fits into the through hole.

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