Joint structure of structural materials and joint member

Abstract

To provide a joint structure of a structural material which enables two structural materials to be joined easily with stable and high strength, and to provide a joint member.SOLUTION: In a joint structure 1 of structural materials, two structural materials 10, 12 each including a cutout part at an end are arranged so that the cutout parts 16, 18 of the two structural materials 10, 12 are butted to form a joint hole 20. A joint member 14 having a shape which corresponds to a shape of the joint hole 20 is inserted into the joint hole 20 to join the two structural materials 10, 12. The joint member 14 includes an elastic fitting part having a diameter larger than that of the joint hole 20 and including an air gap therein. The elastic fitting part is compressed inward when inserted into the joint hole 20 and restored to be fitted in the joint hole 20 during fitting.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a joining structure for structural materials and a joining member used in such a joining structure. [Background technology]

[0002] 2. Description of the Related Art Conventionally, as a joining structure for wooden structural members such as building interior materials and furniture materials, a joining structure for structural members using a joining member such as a butterfly joint (shredded joint) has been known.

[0003] As an example of a joining structure for structural materials using joining members, there has been proposed a joining structure including a first wooden panel, a second wooden panel, and a shredded joining member joining the first wooden panel and the second wooden panel, the joining structure having an allowable strength of approximately 10 kN or more, the joining member including a laminated timber made of a plurality of laminated plate materials, the plurality of plate materials including a first plate material having a first fiber direction and a second plate material having a second fiber direction different from the first fiber direction, the total volume of the first plate material being larger than the total volume of the second plate material, and the height direction of the joining member being approximately the same as the first fiber direction (see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6846561 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the joint strength of the conventional joint structure of structural materials is not necessarily sufficient.

[0006] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a structural material joining structure and joining member that can easily join two structural materials with stable, high strength. [Means for solving the problem]

[0007] As a result of extensive research into joining structures of structural materials using joining members, the inventors discovered that by using a joining member having an elastic fitting portion that has a diameter larger than the joining hole of the structural material and has an internal gap, the elastic fitting portion that is compressed inward when inserted into the joining hole returns to its original shape when fitted and fits into the joining hole, thereby making it possible to join two structural materials with high strength, which led to the completion of the present invention.

[0008] That is, the present invention is as follows. [1] A joining structure for structural materials, comprising: two structural materials each having a notch at an end, the notches of the two structural materials are butted together to form a joining hole; and a joining member having a shape corresponding to the joining hole is inserted into the joining hole, the two structural materials being joined together; The joining member has an elastic fitting portion having a diameter larger than the joining hole and having a gap therein, and the elastic fitting portion is compressed inward when inserted into the joining hole and restored to its original shape when fitted into the joining hole. A joining structure for structural materials. [2] The joining member is A pilot portion is provided below the elastic fitting portion, has a diameter equal to or smaller than that of the connecting hole, and is inserted into the connecting hole first; a cover portion provided above the elastic fitting portion, having a diameter large enough to be inserted into the joining hole without a gap, and forming the same plane as the upper surfaces of the two structural members; The joint structure of structural materials according to the above [1], characterized in that it comprises: [3] The joining structure of structural materials according to the above [1] or [2], characterized in that the circumferential length of the elastic fitting portion of the joining member is longer than the circumferential length of the joining hole. [4] The joint structure for structural materials according to any one of the above [1] to [3], wherein the joint member is gourd-shaped in plan view. [5] The joint structure for structural materials according to any one of the above [1] to [4], wherein the bottom of the joint member is rounded. [6] The joint structure for structural materials according to any one of the above [1] to [5], wherein the joint member is made of a plant-derived resin. [7] The joint structure of structural materials according to [6] above, characterized in that the plant-derived resin is polylactic acid (PLA). [8] The joining structure of structural materials described in [6] or [7] above, characterized in that the joining member is a member integrally molded by a 3D printer. [9] A joining member used in a joining structure of the structural material according to any one of the above [1] to [8].

[10] A structure comprising a joint structure of the structural material according to any one of [1] to [8] above.

[11] A joining member that is formed in a shape corresponding to a shape of a joining hole formed by butting together the notches of two structural members having notches at their ends, and that fits into the joining hole to join the two structural members, The elastic fitting portion has a diameter larger than the connecting hole and has an internal gap, and the elastic fitting portion is compressed inward when inserted into the connecting hole and returns to its original shape when fitted into the connecting hole. A joining member characterized by: Effect of the Invention

[0009] The joining structure and joining member for structural materials of the present invention can easily join two structural materials with stable high strength. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is an explanatory diagram of a joining structure for structural materials according to a first embodiment of the present invention, showing a state before two structural materials are joined. [Diagram 2]FIG. 2 is an explanatory diagram of the joining structure of structural materials according to the first embodiment of the present invention, and is a schematic diagram of the state after two structural materials have been joined. [Diagram 3] 2 is a schematic side view of a gourd-shaped joining member of the joining structure of the structural material shown in FIG. 1. [Figure 4] 2 is a schematic cross-sectional view of a gourd-shaped joining member of the joining structure of the structural material shown in FIG. 1. [Diagram 5] 11 is an explanatory diagram of a round dumbbell-shaped joint member of a joint structure of a structural material in accordance with a second embodiment of the present invention, where (a) is an oblique view, (b) is a side view, (c) is a plan view, and (d) is a schematic cross-sectional view. [Figure 6] 11A to 11D are explanatory diagrams of a rectangular dumbbell-shaped joint member of a joint structure for structural materials in a third embodiment of the present invention, where (a) is an oblique view, (b) is a side view, (c) is a plan view, and (d) is a schematic cross-sectional view. [Figure 7] 13A, 13B, 13C, and 13D are explanatory diagrams of a diamond-shaped joint member of a joint structure for structural materials according to a fourth embodiment of the present invention, in which (a) is a perspective view, (b) is a side view, (c) is a plan view, and (d) is a schematic cross-sectional view. [Figure 8] 13A to 13D are explanatory diagrams of an arrow-shaped joint member of a joint structure of structural materials according to a fifth embodiment of the present invention, where (a) is a perspective view, (b) is a side view, (c) is a plan view, and (d) is a schematic cross-sectional view. [Figure 9] Photographs showing a gourd-shaped joint member produced in an embodiment, where (a) is a diagonal upward photograph, (b) is a side photograph, (c) is a plan photograph, and (d) is a diagonal downward photograph. [Figure 10] 3A and 3B are photographs of a structure having a joint structure of structural materials using a joining member of the present invention produced in an example, where (a) is an overall photograph and (b) is an enlarged photograph of the joint portion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The joining structure for structural materials of the present invention is a joining structure for structural materials in which two structural materials having cutouts at their ends are arranged so that the cutouts of the two structural materials are butted together to form a joining hole, and a joining member corresponding to the shape of the joining hole is inserted into the joining hole, wherein the joining member has an elastic fitting portion which has a diameter larger than the joining hole and has an internal gap, and the elastic fitting portion is compressed inward when inserted into the joining hole, and returns to its original shape when fitted so as to fit into the joining hole.

[0012] The joining structure for structural materials of the present invention can easily join two structural materials with stable, high strength.

[0013] The joining structure for structural materials of the present invention can be suitably used for joining building interior materials and furniture materials such as base materials, wooden parts, tabletops, shelves, etc. It can also be used for the purpose of reinforcing structural materials and improving their design.

[0014] As described above, the joining structure of structural materials of the present invention comprises two structural materials each having a notch at its end, and a joining member.

[0015] [Structural material] First, the structural material of the present invention will be described. The joining structure of structural materials of the present invention comprises two structural materials. The two structural materials each have a notch at the end, and are arranged so that the notches of the respective structural materials are butted together to form a joining hole. In other words, when the two structural materials are placed adjacent to each other, the end side faces having the notch can abut (see FIG. 1). The shape of the ends of the structural materials may be straight or curved as long as they match when butted together, but is usually straight.

[0016] The material of the structural member is not particularly limited, but is preferably wood. The shape of the structural member may be, for example, a plate, a rectangular column, a block, or any other shape.

[0017] When the structural material is a wooden flat plate member, the structural material may be arranged, for example, with the end grain faces butted together, with the end grain faces of the structural material butted together, or with the end grain or end grain face of the structural material butted against the front or back wood surface of the structural material.

[0018] (Notch) The cutout is a hole cut inward from the end side of the structural material. The cutout may be formed to penetrate the upper and lower surfaces of the structural material, but it is preferable that it does not penetrate all the way through. Furthermore, it is preferable that the gap width of the cutout at a position a certain distance inward from the end side of the structural material is longer than the gap width at the end side of the structural material (the length of the gap formed at the end side of the structural material). In other words, it is preferable that the cutout has a portion that is narrowed toward the end side of the structural material. This makes the joining strength against a force that tries to pull the two structural materials apart stronger.

[0019] (joining hole) A joint hole is a hole formed by butting the cutouts of two structural materials together. In other words, a joint hole is a hole formed by connecting two holes formed in structural materials to form a single hole.

[0020] The joining hole may be symmetrical or asymmetrical about the butted end side faces of the two structural members, but a symmetrical shape is preferable. In other words, it is preferable that the two structural members have cutouts of the same shape.

[0021] [Jointing material] Next, the joining member of the present invention will be described. The joining member is formed to a shape corresponding to the shape of the joining hole, and is provided with an elastic fitting portion having a larger diameter than the joining hole and an internal gap. In other words, the joining member is formed to be substantially the same shape as the joining hole, and is inserted into the joining hole, and the elastic fitting portion fits into the joining hole inside the joining hole, thereby joining the two structural members.

[0022] (Shape of joining material) Examples of the shape of the joining member in plan view include a gourd shape (see FIG. 3), a round dumbbell shape (see FIG. 5), a square dumbbell shape (see FIG. 6), a diamond shape (see FIG. 7), an arrow shape (see FIG. 8), a butterfly joint shape (shredded shape), an anchor shape, etc. The shape of the joining member is preferably one having a circular portion in plan view from the viewpoint of ease of processing, and specifically, a gourd shape or a round dumbbell shape is preferable, and a gourd shape is more preferable.

[0023] (Size of joining parts) The overall size of the joining member is not particularly limited and can be changed appropriately depending on the application, but for example, it has a maximum length (see X in FIG. 1) of 10 to 400 mm, a maximum width (see Y in FIG. 1) of 5 to 200 mm, and a maximum height (see Z in FIG. 1) of 5 to 200 mm, preferably a maximum length of 10 to 100 mm, a maximum width of 5 to 50 mm, and a maximum height of 5 to 50 mm, more preferably a maximum length of 12 to 60 mm, a maximum width of 6 to 30 mm, and a maximum height of 6 to 30 mm, and even more preferably a maximum length of 14 to 20 mm, a maximum width of 7 to 10 mm, and a maximum height of 7 to 10 mm.

[0024] When the joining hole has a shape having a circular portion in a plan view, the joining member has a diameter (Y in FIG. 1) of, for example, 5 to 200 mm, preferably 5 to 50 mm, more preferably 6 to 30 mm, and even more preferably 7 to 10 mm.

[0025] The elastic fitting portion of the joining member has a diameter larger than the joining hole and has an internal gap, is compressed inward when inserted into the joining hole, and returns to its original shape when fitted into the joining hole. Here, the elastic fitting portion having a diameter larger than the joining hole means that there is a portion of the periphery that is large enough to join the structural material, and at least each cutout portion has a large diameter. Therefore, the elastic fitting portion is formed, for example, with a perimeter that is longer than the perimeter of the joining hole.

[0026] Specifically, the elastic fitting portion preferably has a portion that protrudes outward from the outer periphery of the joining hole by approximately 0.2 to 8.0 mm, more preferably by 0.3 to 3.0 mm, and even more preferably by 0.4 to 1.0 mm.

[0027] The gap of the elastic fitting part is a space formed inside the elastic fitting part. The gap is compressed inward during insertion, allowing a large-diameter elastic fitting part to be inserted into the joining hole. The gap also functions as a cushioning material (shock absorber) that absorbs shock when the joining member is driven into the joining hole with a hammer or the like.

[0028] The gap is preferably provided at a position a predetermined distance inward from the peripheral wall of the elastic fitting portion, and is preferably disposed at a position corresponding to the center of each of the cutouts of the two structural members in a plan view. The gaps may be connected to each other.

[0029] In the case where a gap is provided at the center of each of the cutouts of the two structural materials, the shape of each gap is preferably circular in plan view, and examples of such shapes include a sphere, an ellipsoid, a cylinder, and a bicone, with a sphere or an ellipsoid being preferred. This allows the vertical force during insertion to be efficiently dispersed, improving durability. The height of the gap (vertical length) may be a part of the height of the elastic fitting portion, but is preferably formed to be equal to or greater than the height of the elastic fitting portion.

[0030] In the case where the gap forms a circle in a plan view, the maximum diameter of the circle can be set appropriately depending on the size of the connecting member, and is, for example, 2.0 to 80 mm, preferably 2.5 to 25 mm, more preferably 3.0 to 15 mm, and even more preferably 3.5 to 5.0 mm.

[0031] The joining member of the present invention preferably has a pilot portion and a lid portion below and above the elastic fitting portion, respectively. That is, it is preferable that the joining member has a pilot portion provided below the elastic fitting portion, has a diameter equal to or smaller than that of the joining hole, and is inserted into the joining hole first, and a lid portion provided above the elastic fitting portion, has a diameter large enough to be inserted into the joining hole without a gap, and forms the same plane as the upper surfaces of the two structural materials. The elastic fitting portion, the pilot portion, and the lid portion may be molded separately, but are preferably molded integrally. The pilot portion, which is the bottom portion, is preferably rounded. This allows the joining member to be smoothly inserted into the joining hole.

[0032] Examples of the material of the elastic fitting part include plastic (synthetic resin) and rubber, with plastic being preferred. As the plastic, those that can be used in 3D printers are preferred, with specific examples including hard polyvinyl chloride resin, polypropylene resin, hard polyethylene resin, polylactic acid (PLA), and the like, with polylactic acid being preferred. Polylactic acid is a plant-derived biodegradable plastic made from starch contained in corn and the like, and is a carbon-neutral material, making it environmentally friendly. In addition, plastic (synthetic resin) and rubber are compatible with resin adhesives such as wood glue (aqueous adhesive containing vinyl acetate resin as a component), and therefore the joining strength can be improved. Furthermore, joining can be performed without using conventional metal fittings such as mortar shells, tie plates, bolts, and nuts, making it environmentally friendly.

[0033] It is preferable to use the same material for the entire joining part (pilot part and lid part) as for the elastic fitting part. For example, if the joining part is made of plastic that is compatible with 3D printers, the entire joining part can be molded as a single unit using a 3D printer. When using a 3D printer, compared to joining structures of structural materials using conventional joining parts, no skilled techniques are required, and the quality of the product is not affected by the skill of the worker, so it can be used as a standard product or a ready-made product. In addition, it can shorten the processing time and reduce costs, and the size can be freely changed.

[0034] Next, a structure using the joint structure of the structural material of the present invention will be described. The structure of the present invention includes a structure having the above-mentioned joint structure. Examples of such structures include furniture and its components, buildings and its components, etc.

[0035] Next, a joining member that can be applied to the joining structure of the structural material of the present invention will be described. The joining member of the present invention is formed into a shape corresponding to the shape of a joining hole formed by butting together the notches of two structural materials each having a notch at its end, and fits into the joining hole to join the two structural materials.The joining member is characterized in that it has an elastic fitting portion which has a diameter larger than the joining hole and has an internal gap, and which is compressed inward when inserted into the joining hole and returns to its original shape when fitted, so that it fits into the joining hole. The joining members have the same configuration as those described in the joining structure of the structural materials above, and therefore a description thereof will be omitted.

[0036] Hereinafter, first to fifth embodiments of the joining structure for structural materials of the present invention will be specifically described with reference to the drawings, but the present invention is not limited to these embodiments.

[0037] Here, Fig. 1 is an explanatory diagram of the joining structure of structural materials according to the first embodiment of the present invention, showing the state before two structural materials are joined. Fig. 2 is an explanatory diagram of the joining structure of structural materials according to the first embodiment of the present invention, showing a schematic diagram of the state after two structural materials are joined. Fig. 3 is a schematic side view of a gourd-shaped joining member of the joining structure of structural materials shown in Fig. 1. Fig. 4 is a schematic cross-sectional view of the gourd-shaped joining member of the joining structure of structural materials shown in Fig. 1.

[0038] 1 and 2, a joining structure 1 of structural materials according to a first embodiment of the present invention includes a rectangular structural material 10, a rectangular structural material 12, and a gourd-shaped joining member 14. The rectangular structural material 10 and the rectangular structural material 12 are members having the same configuration.

[0039] As shown in Figures 1 and 2, the rectangular structural material 10 is a wooden block approximately 35 mm long, 20 mm wide, and 9.0 mm high, and has a cylindrical cutout 16 approximately 9.0 mm in diameter and 8.5 mm high in the center of one end (the center of the corner between the wooden surface and the butt end surface).

[0040] 1 and 2, the joining structure 1 of structural materials is arranged so that the notch 16 of the rectangular structural material 10 and the notch 18 of the rectangular structural material 12 are butted against each other to form a joining hole 20. The joining hole 20 is a gourd-shaped hole in a plan view symmetrical about the butted end side faces of the rectangular structural material 10 and the rectangular structural material 12. The joining hole 20 is formed to have a length in the longitudinal direction of 16 mm, a maximum length in the lateral direction of 9.0 mm, a minimum length (the width at the butted end side faces) of 4.6 mm, and a height of 8.5 mm.

[0041] 3, the gourd-shaped joint member 14 is a member formed in a gourd shape in plan view so that two cylinders are connected. The gourd-shaped joint member 14 has an elastic fitting portion 22, and has a pilot portion 24 and a lid portion 26 respectively above and below the elastic fitting portion 22. The elastic fitting portion 22, the pilot portion 24, and the lid portion 26 are made of plastic such as polylactic acid, and are integrally molded by a 3D printer.

[0042] 3, the elastic fitting portion 22 is 17 mm long, 9.5 mm wide, and 2.5 mm high, and has a larger diameter than the connecting hole 20. The pilot portion 24 is 15 mm long, 8.5 mm wide, and 3.5 mm high, and has a smaller diameter than the connecting hole 20 and is rounded. The lid portion 26 is 16 mm long, 9.0 mm wide, and 2.5 mm high, and has a diameter large enough to be inserted into the connecting hole 20 without any gaps.

[0043] 4, elastic fitting portion 22 has therein gaps 28a, 28b which are circular in shape with a maximum diameter of about 3.5 mm and a height of about 5.5 mm in a plan view. Gaps 28a, 28b are provided at positions a predetermined distance inward from the peripheral wall of elastic fitting portion 22, and are disposed at positions corresponding to the centers of notches 16 of rectangular structural member 10 and notches 18 of rectangular structural member 12, respectively, in a plan view.

[0044] In the structural material joining structure 1 described above, the gourd-shaped joining member 14, which corresponds to the shape of the joining hole 20, is provided with an elastic fitting portion 22 which has a diameter larger than the joining hole 20 and has internal gaps 28a, 28b. The elastic fitting portion 22 is compressed inward when inserted into the joining hole 20 and returns to its original shape when fitted, so that it fits into the joining hole 20. This makes it possible to easily join the rectangular structural materials 10 and 12 with stable, high strength.

[0045] Next, the joining structures of structural materials according to the second to fifth embodiments of the present invention will be described in detail. The second to fifth embodiments differ from the first embodiment in that the shapes of the joining members are different. The two structural materials correspond to the joining members, and their description will be omitted. The same reference numerals will be used to designate members having the same configuration as the joining structure 1 of the structural materials according to the first embodiment, and their description will be omitted.

[0046] Here, Fig. 5 is an explanatory diagram of a round dumbbell-shaped joint member of a joint structure of a structural material according to a second embodiment of the present invention, where (a) is a perspective view, (b) is a side view, (c) is a plan view, and (d) is a schematic cross-sectional view. Fig. 6 is an explanatory diagram of a square dumbbell-shaped joint member of a joint structure of a structural material according to a third embodiment of the present invention, where (a) is a perspective view, (b) is a side view, (c) is a plan view, and (d) is a schematic cross-sectional view. Fig. 7 is an explanatory diagram of a diamond-shaped joint member of a joint structure of a structural material according to a fourth embodiment of the present invention, where (a) is a perspective view, (b) is a side view, (c) is a plan view, and (d) is a schematic cross-sectional view. Fig. 8 is an explanatory diagram of an arrow-shaped joint member of a joint structure of a structural material according to a fifth embodiment of the present invention, where (a) is a perspective view, (b) is a side view, (c) is a plan view, and (d) is a schematic cross-sectional view.

[0047] As shown in Fig. 5, the round dumbbell-shaped joint member 30 of the joint structure for structural materials according to the second embodiment of the present invention is a member formed in a round dumbbell shape in a plan view so that two cylinders are connected by a rectangular member. The round dumbbell-shaped joint member 30 has a pilot portion 34 and a lid portion 36 respectively above and below an elastic fitting portion 32 provided in the center.

[0048] As shown in Fig. 6, a square dumbbell-shaped joint member 40 of a joining structure for structural materials according to a third embodiment of the present invention is a member formed in a square dumbbell shape in a plan view so that two square prisms are connected by a rectangular member. The square dumbbell-shaped joint member 40 has a pilot portion 44 and a lid portion 46 respectively above and below an elastic fitting portion 42 provided in the center.

[0049] 7, a diamond-shaped joint member 50 of a joining structure for structural materials according to a fourth embodiment of the present invention is a member formed in a shape of two continuous diamonds in a plan view so that two diamond-shaped columns are connected. The diamond-shaped joint member 50 has an elastic fitting portion 52, and has a pilot portion 54 and a cover portion 56 above and below the elastic fitting portion 52, respectively.

[0050] As shown in Fig. 8, the arrow-shaped joint member 60 of the joining structure for structural materials according to the fifth embodiment of the present invention is a member formed in a double-arrow shape in a plan view, in which two triangular prisms are connected by a rectangular member. The arrow-shaped joint member 60 has a pilot portion 64 and a cover portion 66 respectively above and below an elastic fitting portion 62 provided in the center.

[0051] The joining members 30, 40, 50, 60 of the joining structure of the structural members according to the second to fifth embodiments of the present invention described above are provided with elastic fitting parts 32, 42, 52, 62 having a diameter larger than the joining hole 20 and having a void 28 therein, and the elastic fitting parts 32, 42, 52, 62 are compressed inward when inserted into the joining hole 20, and are restored when fitted to be fitted into the joining hole 20, so that the joining structure of the structural members according to the present invention using the joining members 30, 40, 50, 60 can easily join two structural members with stable high strength. Furthermore, the joining structure of the structural members according to the present invention can be applied to structural members forming joining holes of various shapes and joining members corresponding to the joining holes, so long as it has the above configuration. EXAMPLES

[0052] Specific examples of the present invention will be described below, but the scope of the present invention is not limited to these examples.

[0053] A joint member for a joint structure of structural materials according to the first embodiment of the present invention was manufactured. Specifically, a gourd-shaped joint member was manufactured using a 3D printer. Polylactic acid was used as the material for the 3D printer. FIG. 9 is a set of photographs showing the gourd-shaped joint member produced in the examples, where (a) is a photograph taken from diagonally above, (b) is a photograph taken from the side, (c) is a photograph taken from a top, and (d) is a photograph taken from diagonally below.

[0054] Specifically, the elastic fitting portion of the gourd-shaped joining member produced in the embodiment had a longitudinal length of 17 mm, a lateral maximum length (diameter of the circular portion) of 9.5 mm, and a height of 2.5 mm. The pilot portion of the joining member had a longitudinal length of 15 mm, a lateral maximum length (diameter of the circular portion) of 8.5 mm, and a height of 3.5 mm. The lid portion of the joining member had a longitudinal length of 16 mm, a lateral maximum length (diameter of the circular portion) of 9.0 mm, and a height of 2.5 mm. The size of the internal ellipsoidal gap was about 3.5 mm in maximum diameter and about 5.5 mm in height when viewed in plan.

[0055] Using the produced gourd-shaped joint member, a structure having a joint structure of the structural material of the present invention was manufactured. The structural members used were four rectangular prism members with triangular prism-shaped tips, with a total of four cylindrical notches, each 9.0 mm in diameter and 8.5 mm in height, formed on the left and right inclined sides of the upper and lower surfaces of the triangular prism-shaped tips.

[0056] The tips of four rectangular columnar members (furniture members) were butted together, and the notches of the adjacent rectangular columnar members were arranged to form joint holes. Eight gourd-shaped joint members made in the examples were used to manufacture a cross-structure decorative body measuring 360 mm in length, 280 mm in width, and 40 mm in height. It was confirmed that the structure equipped with the joint structure of structural materials using the joint members of the present invention did not shift between the members even when subjected to strong vibrations, and all the members were firmly joined. It was found that the joint structure of structural materials of the present invention allows structural materials to be easily joined with stable high strength. [Industrial Applicability]

[0057] The joining structure for structural materials of the present invention can be used as a joining structure for furniture members and building members, and is therefore industrially useful. [Explanation of symbols]

[0058] 1. Joint structure of structural materials (first embodiment) 10 Rectangular structural material 12 Rectangular structural material 14 Gourd-shaped joint member 16: Notch of rectangular structural member 10 18: Notch of rectangular structural member 12 20 joint hole 22 Elastic fitting part 24 Pilot Division 26 Lid 28 void 30 Round dumbbell-shaped joint member 32 Elastic fitting part 34 Pilot Division 36 Lid 40 Square dumbbell-shaped joint member 42 Elastic fitting part 44 Pilot Division 46 Lid 50 Diamond-shaped joint member 52 Elastic fitting part 54 Pilot Division 56 Lid 60 Arrow-shaped joint member 62 Elastic fitting part 64 Pilot Division 66 Lid

Claims

1. A joining structure for structural materials, comprising: two structural materials each having a notch at an end, the notch of the two structural materials being butted together to form a joining hole; and a joining member having a shape corresponding to the joining hole being inserted into the joining hole, the two structural materials being joined together, The joining member has an elastic fitting portion having a diameter larger than the joining hole and having a gap therein, and the elastic fitting portion is compressed inward when inserted into the joining hole and restored to its original shape when fitted into the joining hole. A joining structure for structural materials.

2. The joining member is A pilot portion is provided below the elastic fitting portion, has a diameter equal to or smaller than that of the connecting hole, and is inserted into the connecting hole first; a cover portion provided above the elastic fitting portion, the cover portion having a diameter large enough to be inserted into the joining hole without a gap, and the cover portion being flush with the upper surfaces of the two structural members; 2. The joining structure of structural materials according to claim 1, further comprising:

3. 3. The joining structure of structural members according to claim 1, wherein the circumferential length of the elastic fitting portion of the joining member is longer than the circumferential length of the joining hole.

4. 3. The joint structure of structural materials according to claim 1, wherein the joint member is gourd-shaped in a plan view.

5. 3. A joint structure for structural materials according to claim 1, wherein the bottom of said joint member is rounded.

6. 3. The joint structure of structural materials according to claim 1, wherein the joint member is made of a resin derived from plants.

7. 7. The joining structure of structural materials according to claim 6, wherein the plant-derived resin is polylactic acid.

8. The joining structure of structural materials according to claim 6, characterized in that the joining member is a member integrally formed by a 3D printer.

9. A joining member used in the joining structure of the structural materials according to claim 1 or 2.

10. A structure comprising the joint structure for structural materials according to claim 1 or 2.

11. A joining member that is formed in a shape corresponding to a shape of a joining hole formed by butting together the notches of two structural members having notches at their ends, and that fits into the joining hole to join the two structural members, The elastic fitting portion has a diameter larger than the connecting hole and has an internal gap, and the elastic fitting portion is compressed inward when inserted into the connecting hole and returns to its original shape when fitted into the connecting hole. A joining member characterized by:

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