Joint member and skeletal structure

Abstract

A kind of joint member and framework structure, the joint member can improve the joint strength of tubular member each other.Joint member has first joint member (10A), second joint member (20) and fixed component (50), first joint member (10A) has angle tubular angle barrel portion (11);From angle barrel portion (11) respectively to X direction and Y direction extend a pair of first insertion sheet (12) and a pair of first insertion sheet (13);With the fixed slit (14) of each side surface through and inserted fixed component (50) in angle barrel portion (11) each side surface facing each other, second joint member (20) has flat portion (21);From flat portion (21) extend a pair of second insertion sheet (22);From flat portion (21) to the opposite side of second insertion sheet (22) extend and insert angle barrel portion (11) a pair of link insertion sheet (23);With the fixed component holding portion (28) for keeping fixed component (50) is set on a pair of link insertion sheet (23).

Description

TECHNICAL FIELD

[0001] The present application relates to a joint member for joining tubular members and a skeleton structure constructed by joining tubular members with the joint member. BACKGROUND

[0002] As a joint member for joining tubular members such as corner pipes to construct a skeleton structure, the present inventors have proposed a joint member manufactured by extrusion molding of a metal, the joint member having a plurality of insertion pieces into which the tubular members are inserted on the outside (Patent Literature 1).

[0003] In Patent Literature 1, in the case of constructing a three-dimensional skeleton structure, a first joint member and a second joint member are used as the joint members. In detail, the first joint member has a base that is a solid cube having a hole portion that penetrates in the extrusion direction as the Z direction, and a first insertion piece that extends from the side surface of the base in the X direction and the Y direction orthogonal to the Z direction. By inserting the first insertion piece of this first joint member into the end portion of the tubular member, a two-dimensional frame-shaped skeleton structure in the X-Y direction can be constructed. In addition, the second joint member has a protrusion portion that extends from a planar portion of a square, and a second insertion piece that extends from the surface of the planar portion opposite the protrusion portion. Furthermore, by inserting the protrusion portion of the second joint member into the hole portion of the first joint member, and inserting the second insertion piece into the end portion of the tubular member, the tubular member can be disposed upright at a right angle with respect to the two-dimensional frame-shaped skeleton structure, and a three-dimensional frame-shaped skeleton structure can be constructed.

[0004] According to the technology of this Patent Literature 1, because the first joint member and the second joint member (joint members) can be formed from the extrusion molded body on the basis of the tubular member, the tubular member and the joint members can be formed from the same constituent metal material. Thus, by using these joint members, a skeleton structure that does not have the risk of generating strain due to differences in thermal expansion rates can be constructed.

[0005] However, in the technology of Patent Literature 1, because the first joint member and the second joint member are joined by inserting the protrusion portion into the hole portion, it is difficult to obtain sufficient joint strength. Therefore, it can be considered to weld the first joint member and the second joint member, but there are problems in that the welding work takes time and labor, and the environment in which the work can be performed is limited.

[0006] PRIOR ART LITERATURE

[0007] PATENT LITERATURE

[0008] PATENT LITERATURE 1 Japanese Patent Application Publication No. 2021-178330 SUMMARY

[0009] Problems to be Solved by the Invention

[0010] Therefore, the present application has been made in view of the above-mentioned circumstances, and it is an object of the present application to provide a joint member capable of improving the joint strength of tubular members, and a skeleton structure constructed by jointing tubular members by the joint member.

[0011] Means for Solving the Problems

[0012] To solve the above-mentioned problems, the joint member of the present application has a first joint member, a second joint member, and a fixing member, characterized in that,

[0013] The first joint member has a corner tube portion, a pair of first insertion pieces, and a fixing slit,

[0014] The corner tube portion is a corner tube shape of a rectangular parallelepiped or a cube;

[0015] The pair of first insertion pieces respectively extend in an X direction or a Y direction orthogonal to the Z direction from an inner side of each of at least two sides of the four sides of the corner tube portion parallel to the Z direction, at a position apart from each side of a pair of sides extending in the Z direction by a predetermined interval;

[0016] The fixing slit penetrates each of a pair of sides of the corner tube portion facing each other in a thickness direction, and the fixing member is inserted into the fixing slit,

[0017] The second joint member has a flat portion, a pair of second insertion pieces, a pair of connecting insertion pieces, and a fixing member holding portion,

[0018] The flat portion is a flat portion of a square or a rectangle;

[0019] The pair of second insertion pieces extend from the flat portion at a right angle along each of a pair of sides of one side of the flat portion;

[0020] The pair of connecting insertion pieces extend from the flat portion at a right angle along each of a pair of sides of a side of the flat portion opposite to the side in which the pair of second insertion pieces extend, and are inserted into the corner tube portion;

[0021] The fixing member holding portion is provided on each of the pair of connecting insertion pieces, and holds the fixing member between the pair of connecting insertion pieces.

[0022] According to the joining member of the present structure, after a pair of link insertion pieces are inserted into the corner cylinder portion, the first joining member and the second joining member can be joined by inserting the fixing member into the fixing slit and holding the fixing member in the fixing member holding portion provided on the pair of link insertion pieces. By joining the second joining member with the first joining member, the pair of second insertion pieces extending from the planar portion of the second joining member becomes in a state of extending in the Z direction. Furthermore, by oppositely fitting each pair of the pair of first insertion pieces and the pair of second insertion pieces into the end portions of the tubular members, at least two tubular members whose axial directions are the X direction or the Y direction and one tubular member whose axial direction is the Z direction can be joined.

[0023] In this joining member, because the fixing member inserted into the fixing slit provided on the side surface of the corner cylinder portion is held in the fixing member holding portion, relative movement of the second joining member with respect to the axial direction of the corner cylinder portion is prevented, and the first joining member and the second joining member are mechanically joined. Thus, compared with the conventional technology in which two joining members are joined by fitting the protruding portion into the hole portion, the joining strength of the first joining member and the second joining member can be improved. That is, the joining strength of the tubular members whose axial directions are the X direction or the Y direction and the tubular member whose axial direction is the Z direction can be improved. Furthermore, because the joining strength of the first joining member and the second joining member can be improved, unlike the conventional technology, a welding work for joining the two joining members can not be needed.

[0024] The skeleton structure of the present invention is a skeleton structure constructed by joining a tubular member serving as a corner pipe by a joining member provided with a first joining member, a second joining member, and a fixing member, characterized in that,

[0025] The above first joining member is provided with a corner cylinder portion, a pair of first insertion pieces, and a fixing slit,

[0026] The corner cylinder portion is a corner pipe of a rectangular parallelepiped or a cube;

[0027] The pair of first insertion pieces extends in the X direction or the Y direction from a position inside each of at least two side surfaces of the corner cylinder portion parallel to the Z direction as the axial direction, at a prescribed interval from each of the pair of side edges extending in the Z direction;

[0028] The fixing slit penetrates each of the pair of side surfaces facing each other in the corner cylinder portion in the thickness direction, and the fixing member is inserted thereinto,

[0029] The above second joining member is provided with a planar portion, a pair of second insertion pieces, a pair of link insertion pieces, and a fixing member holding portion,

[0030] The planar portion is a planar portion of a square or a rectangle;

[0031] The pair of second insertion pieces extend from the planar portion at right angles along each of a pair of side edges on one surface of the planar portion;

[0032] The pair of connecting insert pieces extend from the plane portion at right angles along each of a pair of side edges on the surface of the plane portion opposite to the surface from which the second insert piece extends, and are inserted into the angled tube portion;

[0033] The fixing member holding portion is provided on each of the pair of connecting insertion pieces and is used to hold the fixing members between each other.

[0034] The second joining member is fixed to the first joining member by inserting the pair of connecting insert pieces into the angled tube portion and holding the fixing member inserted into the fixing slit in the fixing member holding portion.

[0035] The plurality of tubular members are joined by inserting the pair of first insertion pieces and the pair of second insertion pieces into the ends of different tubular members.

[0036] This is a structure of a three-dimensional frame-like skeleton structure constructed by joining tubular members using a joining member comprising the aforementioned first joining member, second joining member, and fixing member. This provides a skeleton structure having a higher joining strength between tubular members than conventional structures. Furthermore, because the skeleton structure is constructed by embedding the members, welding is not required, making it possible to construct the skeleton structure even in environments where welding is difficult.

[0037] Effects of the Invention

[0038] As described above, according to the present invention, it is possible to provide a joining member capable of improving the joining strength between tubular members and a skeleton structure constructed by joining tubular members using the joining member. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1(a) is a top view of the L-shaped first joining member, Figure 1(b) is a front view of the L-shaped first joining member, Figure 1(c) is a stereoscopic view of the L-shaped first joining member, and Figure 1(d) is a diagram illustrating a method for manufacturing the L-shaped first joining member from a first extruded body.

[0040] Figure 2 (a) is a front view of the second joining member, Figure 2 (b) is a right view of the second joining member, Figure 2 (c) is a stereoscopic view of the second joining member, Figure 2 (d) is a figure illustrating a method for manufacturing the second joining member from a second extruded body, and Figure 2 (e) is a figure illustrating a method for manufacturing the second joining member following Figure 2 (d).

[0041] Fig. 3(a) is a front view of the third joint member, Fig. 3(b) is a right side view of the third joint member, Fig. 3(c) is a perspective view of the third joint member, Fig. 3(d) is a view that explains a method of manufacturing the third joint member from a third extrusion-molded body, and Fig. 3(e) is a view that explains the method of manufacturing the third joint member following Fig. 3(d).

[0042] Figure 4 is a perspective view of the fixing member.

[0043] Figure 5 is a perspective view of the wedge member.

[0044] Figure 6 is an exploded perspective view of the skeleton structure body which is a three-dimensional frame shape.

[0045] Figure 7 is a partial perspective view that enlargedly shows a portion of Figure 6 from the direction of arrow A.

[0046] Fig. 8(a) is a sectional view that cuts the center of the corner cylinder portion in Figure 7 with a plane orthogonal to the Y direction, and Fig. 8(b) is a sectional view that cuts the center of the fixing member in Figure 7 with a plane orthogonal to the Z direction.

[0047] Figure 9 is an exploded perspective view that shows each member of Figure 7 in pieces.

[0048] Fig. 10(a) is a plan view of a first joint member which is a T shape, and Fig. 10(b) is a perspective view of the first joint member which is a T shape.

[0049] Fig. 11(a) is a plan view of a first joint member which is a cross shape, and Fig. 11(b) is a perspective view of the first joint member which is a cross shape.

[0050] Fig. 12(a) is an exploded perspective view of joint members which have one first joint member and two second joint members, Fig. 12(b) is a perspective view that shows the joint members of Fig. 12(a) in an assembled state, and Fig. 12(c) is a sectional view that cuts the center of the corner cylinder portion in the joint members of Fig. 12(b) with a plane orthogonal to the Y direction.

[0051] Fig. 13(a) is an exploded perspective view of joint members used in a skeleton structure body which is a two-dimensional frame shape, Fig. 13(b) is a perspective view that shows the joint members of Fig. 13(a) in an assembled state, and Fig. 13(c) is a sectional view that cuts the center of the corner cylinder portion in the joint members of Fig. 13(b) with a plane orthogonal to the Y direction. DETAILED DESCRIPTION

[0052] Modes for carrying out the invention

[0053] Hereinafter, multiple types of joining members, skeleton structures constructed using these joining members, and methods for manufacturing these joining members will be described as specific embodiments of the present invention using the drawings.

[0054] The skeleton structure of this embodiment is constructed by joining tubular members 70 with joining members. Tubular member 70 is an extruded, angular tube, and its cross-section perpendicular to the axial direction (hereinafter referred to as the "orthogonal cross-section") has a square shape. Here, the length of one side of the square forming the outer shape of the orthogonal cross-section is L, and the wall thickness of tubular member 70 is d (see Figure 8(a)). Thus, the length of one side of the square forming the inner shape of the orthogonal cross-section of tubular member 70 is L - 2d.

[0055] The tubular member 70 has slits 75 near each of the two end portions, each of which penetrates two parallel side surfaces among the four side surfaces in the thickness direction (see Figure 9 The slits 75 extend in a direction perpendicular to the axial direction of the tubular member 70, but do not penetrate the side surface in this direction. Such slits 75 are manufactured by performing a hole-forming process on the tubular member as an extruded body.

[0056] In this embodiment, the first, second, and third joining members 20 and 40 are used as joining members. Furthermore, a fixing member 50 for fixing the first and second joining members 20 and a wedge member 60 for reinforcing the joining are used to construct the skeleton structure.

[0057] In this embodiment, there are three types of first joining members. To distinguish them, they are referred to as the L-shaped first joining member 10A (see FIG1(a)), the T-shaped first joining member 10B (see FIG10(a)), and the cross-shaped first joining member 10C (see FIG11). Otherwise, they are simply referred to as the first joining member. Details will be described later, but for each type of first joining member, there are two types with two fixing slits 14 on each of the two parallel side surfaces of the square tube portion 11 (see FIG12(a)). Therefore, there are six types of first joining members in total. To distinguish between types with different numbers of fixing slits 14, the type with one fixing slit 14 is assigned the same reference numerals as above, while the type with two fixing slits 14 is referred to as the L-shaped first joining member 10A', the T-shaped first joining member 10B', and the cross-shaped first joining member 10C'.

[0058] The first joint member of any type has a corner pipe portion 11 that is angularly tubular. Here, in the first joint member, the axial direction of the corner pipe portion 11 is referred to as the Z direction, and the two directions orthogonal to the Z direction are referred to as the X direction and the Y direction.

[0059] The first joint member has one or two pairs of first insertion pieces 12, one or two pairs of first insertion pieces 13, and a fixed slit 14 in addition to the corner pipe portion 11. The first insertion pieces 12, 13 are each composed of a pair of members that extend in the same direction from one of the four side surfaces of the corner pipe portion 11. One pair of first insertion pieces 12 extends in the X direction from positions that are separated by a prescribed interval inward from each of a pair of side edges that extend in the Z direction in the side surfaces of the corner pipe portion 11. One pair of first insertion pieces 13 extends in the Y direction from positions that are separated by a prescribed interval inward from each of a pair of side edges that extend in the Z direction in the side surfaces of the corner pipe portion 11. The fixed slit 14 penetrates both of the parallel side surfaces of the corner pipe portion 11 in the thickness direction. The L-shaped first joint member 10A has one pair of first insertion pieces 12 and one pair of first insertion pieces 13. The T-shaped first joint member 10B has one pair of one of the first insertion pieces 12 and the first insertion pieces 13 and two pairs of the other. The cross-shaped first joint member 10C has two pairs of first insertion pieces 12 and two pairs of first insertion pieces 13.

[0060] The outer shape and the inner shape of the corner pipe portion 11 of the first joint member as viewed in the Z direction are each a square. The length of one side of the square that is the outer shape is L. In addition, if the wall thickness of the corner pipe portion 11 is d' (see FIG. 8(a)), the length of one side of the square that is the inner shape is L-2d'. The wall thickness d' of this corner pipe portion 11 is thicker than the wall thickness d of the tubular member 70. Therefore, the outer shape of the corner pipe portion 11 as viewed in the Z direction is the same size as the outer shape of the orthogonal cross section of the tubular member 70, whereas the inner shape of the corner pipe portion 11 as viewed in the Z direction is smaller than the inner shape of the orthogonal cross section of the tubular member 70.

[0061] In the first joint member, one pair of first insertion pieces 12 and one pair of first insertion pieces 13 extend from "positions separated by a prescribed interval inward" from each of a pair of side edges that extend in the Z direction in the corner pipe portion 11. This "prescribed interval" is set to be approximately equal to the wall thickness d of the tubular member 70.

[0062] The fixing slit 14 in the first joint member is formed as an elongated hole long in a direction orthogonal to the Z direction along the side surface of the corner cylinder portion 11. The fixing slits 14 provided on the two parallel side surfaces of the corner cylinder portion 11 are respectively provided at the same position in the Z direction and are provided at a position deviated to one side from the center in the Z direction in the corner cylinder portion 11. In this fixing slit 14, the fixing member 50 is inserted (embedded). The width in the Z direction in the two fixing slits 14 provided on the parallel side surfaces is different, and the width of one is the same as the thickness of the flat plate portion 51 described later in the fixing member 50, and the width of the other is the same as the thickness of the head portion 52 in the fixing member 50.

[0063] The first joint member has a wedge holding portion 15 for holding the wedge member 60 between the respective pairs of the opposite members in the pair of the first insertion pieces 12 and the pair of the first insertion pieces 13. In detail, the first joint member has two inner protrusions 16 each protruding toward the opposite member in the facing inner surfaces of the pair of the first insertion pieces 12 and the pair of the first insertion pieces 13. The inner protrusions 16 are formed over the entire length in the Z direction of the respective first insertion pieces 12 and 13. The positions of the inner protrusions 16 in the first insertion pieces 12 and 13 are set in such a manner that the inner protrusion 16 provided on one insertion piece of the pair and the inner protrusion 16 provided on the other insertion piece of the pair face each other. Further, the inner surface of each of the first insertion pieces 12 and 13 is recessed between the two inner protrusions 16 more than other portions. The wedge holding portion 15 as a gap into which the wedge member 60 is inserted to be held is formed between the pair of the first insertion pieces 12 and the pair of the first insertion pieces 13 by the four inner protrusions 16, respectively. The distance from the corner cylinder portion 11 to the center of the wedge holding portion 15 is the same as the distance from the end portion to the center of the slit 75 in the tubular member 70.

[0064] In addition, the first joint member has an inclined protrusion 17 provided near the front end of the outer surface of each of the pair of the first insertion pieces 12 and the pair of the first insertion pieces 13 and a plurality of outer protrusions 18 provided on the outer surface of each of the pair of the first insertion pieces 12 and the pair of the first insertion pieces 13. The inclined protrusion 17 is provided in such a manner that it is inclined outward on the side of the front end from the front end of each of the outer surfaces of the first insertion pieces 12 and 13 on the side of the front end compared to the wedge holding portion 15. Each of the plurality of outer protrusions 18 protrudes outward from the outer surface of each of the first insertion pieces 12 and 13 on the side of the corner cylinder portion 11 compared to the wedge holding portion 15. The direction in which the plurality of outer protrusions 18 are continuously provided is the direction of the extension of each of the first insertion pieces 12 and 13. These inclined protrusions 17 and outer protrusions 18 are formed over the entire length in the Z direction of each of the first insertion pieces 12 and 13.

[0065] Any of the first joining members 10A, 10B, 10C is manufactured by an extrusion molding process to obtain an extrusion molded body made of metal, a cutting process to cut the extrusion molded body by a plane orthogonal to the extrusion direction, and a cutting-off process to cut off a prescribed portion of the cut body obtained by the cutting process.

[0066] In the L-shaped first joining member 10A, as shown in FIG. 1(d), a pair of first insertion pieces 12 extends from one of the four side surfaces of the corner cylinder portion 11 in the X direction, and a pair of first insertion pieces 13 extends from the adjacent side surface in the Y direction.

[0067] This L-shaped first joining member 10A, after cutting the first extrusion molded body EB1 (see FIG. 1(d)) extending in the Z direction (extrusion direction) with the shape shown in FIG. 1(a) as a certain cross-sectional shape by a plane (XY plane, i.e., the plane indicated by a single-dot chain line in FIG. 1(d)) orthogonal to the Z direction, is manufactured by cutting off in a manner to form the fixed slit 14 in the two parallel side surfaces in the corner cylinder portion 11. In the cutting process, the first extrusion molded body EB1 is cut at a position at a distance of L-2d in the Z direction from the end portion.

[0068] The second joining member 20 of the present embodiment has a flat portion 21 which is flat and square, a pair of second insertion pieces 22, and a pair of link insertion pieces 23. The pair of second insertion pieces 22 extends at right angles to the flat portion 21 from positions inside each of the pair of side edges of the flat portion 21 by only a prescribed interval. The pair of link insertion pieces 23 extends at right angles to the flat portion 21 from positions inside each of the pair of side edges of the flat portion 21 by only a second prescribed interval.

[0069] The length of one side of the square shape of the flat portion 21 as an outer shape is L, and the thickness is d which is the same as the wall thickness of the tubular member 70. The pair of second insertion pieces 22 is provided at positions inside each of the pair of side edges of the flat portion 21 by only a prescribed interval. This "prescribed interval" is set to be substantially the same as the wall thickness d of the tubular member 70 as in the "prescribed interval" of the pair of first insertion pieces 12 and the pair of first insertion pieces 13 in the first joining member. On the other hand, the pair of link insertion pieces 23 is provided at positions inside each of the pair of side edges of the flat portion 21 by only a second prescribed interval. This "second prescribed interval" is set to be substantially the same as the wall thickness d' of the corner cylinder portion 11 in the first joining member. The pair of side edges of the pair of link insertion pieces 23 by only the second prescribed interval is the same as the pair of side edges of the pair of second insertion pieces 22 by only the prescribed interval. Further, the lengths by which the pair of link insertion pieces 23 extends from the flat portion 21 are different.

[0070] The second engaging member 20 has, like the first insertion pieces 12, 13 of the first engaging member, a wedge retaining portion 24 for retaining the wedge member 60 between the pair of second insertion pieces 22. The wedge retaining portion 24 of the second engaging member 20 is formed by four inner protrusions 25. The inner protrusions 25 are of the same structure as the inner protrusions 16 that form the wedge retaining portion 15 in the first insertion pieces 12, 13.

[0071] In addition, the second engaging member 20 has an inclined protrusion 26 provided near the front end of the outer surface of each of the pair of second insertion pieces 22 and a plurality of outer protrusions 27 provided on the outer surface of each of the pair of second insertion pieces 22. The inclined protrusion 26 and the outer protrusions 27 are of the same structure as the inclined protrusion 17 and the outer protrusions 18 of the first engaging member, respectively.

[0072] Further, the second engaging member 20 has a fixing member retaining portion 28 for retaining the fixing member 50 between the pair of link insertion pieces 23. Specifically, retaining protrusions 29 protrude toward the opposite member from the facing inner surfaces of each of the pair of second insertion pieces 22. The pair of retaining protrusions 29 each have a groove in the front end surface. The pair of retaining protrusions 29 are disposed in a manner facing each other. In the second engaging member 20, between the grooves in the front end surfaces of each of the pair of retaining protrusions 29, the fixing member retaining portion 28 as a gap into which the fixing member 50 is inserted to be retained is formed. The distance from the planar portion 21 to the center of the fixing member retaining portion 28 is the same as the distance from the end portion in the Z direction of the angular cylinder portion 11 to the center of the fixing slit 14.

[0073] In the link insertion piece 23 of the shorter length extending from the planar portion 21 among the pair of link insertion pieces 23, the portion on the front end side is a first extension portion 30 compared with the retaining protrusion 29, and in the link insertion piece 23 of the longer length extending from the planar portion 21, the portion on the front end side is a second extension portion 31 compared with the retaining protrusion 29. Also, the outer surface of the first extension portion 30 is located inside compared with the extension of the outer surface of the other portion in the link insertion piece 23 in which the link insertion piece 23 itself is disposed, and the outer surface of the second extension portion 31 is located on the extension of the outer surface of the other portion in the link insertion piece 23 in which the link insertion piece 23 itself is disposed. The distance from the outer surface of the first extension portion 30 to the extension of the outer surface of the other portion in the link insertion piece 23 is equal to the thickness of the second extension portion 31.

[0074] The locking claw portion 32 is provided on the linking insert piece 23 having the first extension portion 30, and protrudes outward from the front end of the first extension portion 30. The first recessed portion 33 is recessed from the outer surface of the linking insert piece 23 on the planar portion 21 side compared with the boundary of the holding protrusion 29 and the first extension portion 30. The first recessed portion 33 is recessed inward compared with the outer surface of the first extension portion 30, and locks the first claw portion 44 of the third engaging member 40 described later.

[0075] On the other hand, the second recessed portion 34 is provided on the linking insert piece 23 having the second extension portion 31. The second recessed portion 34 is recessed from the inner surface on the second extension portion 31 side compared with the boundary of the holding protrusion 29 and the second extension portion 31. The locking claw portion 32 or the second claw portion 46 of the third engaging member 40 described later is locked in the second recessed portion 34.

[0076] Further, the second engaging member 20 is provided with a base portion 35 and a plurality of protrusions 36. The base portion 35 contacts the planar portion 21 in a flat plate shape, and links the pair of linking insert pieces 23 to each other. The protrusions 36 are provided on the outer surfaces of the respective linking insert pieces 23. The base portion 35 reinforces the base end portions of the planar portion 21 and the respective linking insert pieces 23. The plurality of protrusions 36 respectively protrude linearly in directions orthogonal to the directions in which the linking insert pieces 23 extend from the planar portion 21. The directions in which the plurality of protrusions 36 are continuously provided are the directions in which the linking insert pieces 23 extend. Further, the protrusions 36 are not provided on the outer surfaces of the first extension portions 30.

[0077] This second engaging member 20 is also manufactured from an extrusion-molded body of metal. Here, in the second engaging member 20, a direction parallel to the planar portion 21 and orthogonal to the direction in which the pair of second insert pieces 22 are spaced apart is taken as a Z direction that is an extrusion direction. A direction orthogonal to the Z direction and parallel to the planar portion 21 is taken as an X direction. A direction orthogonal to the Z direction and orthogonal to the planar portion 21 is taken as a Y direction (see FIG. 2(d)).

[0078] The second engaging member 20 is manufactured by an extrusion molding process that forms a certain cross-sectional shape of the outer shape shown in the front view of FIG. 2(a) to form a second extrusion-molded body EB2 (see FIG. 2(d)) that extends in the extrusion direction (Z direction), a cutting process that cuts the second extrusion-molded body EB2 in a plane (XY plane) orthogonal to the Z direction, and a cutting process that cuts a prescribed portion of the cut body EB2' obtained by the cutting process.

[0079] In the cutting step, the second extrusion-molded body EB2 is cut at a position at a distance L in the Z direction from the end. In the cutting-away step, a prescribed range (hatched portion in Fig. 2(e)) is cut away from both ends in the Z direction of the cut body EB2', except for the flat portion 21. Specifically, a range of a distance d from each of both ends in the Z direction is cut away with respect to the pair of second insertion pieces 22, and a range of a distance d' from each of both ends in the Z direction is cut away with respect to the pair of link insertion pieces 23 and the base portion 35.

[0080] Thus, the flat portion 21 has a square shape with a length of L on one side. In addition, the length in the Z direction of the pair of second insertion pieces 22 becomes L-2d, and becomes the length of the end portion of the tubular member 70 into which the pair of second insertion pieces 22 are fitted, and the length in the Z direction of the pair of link insertion pieces 23 and the base portion 35 becomes L-2d', and becomes the length of the corner cylinder portion 11 of the first joint member into which the pair of link insertion pieces 23 and the base portion 35 are fitted.

[0081] The third joint member 40 of the present embodiment has a flat plate portion 41 that has a square shape, and a first holding piece 42 and a second holding piece 43 that extend from the flat plate portion 41. The first holding piece 42 and the second holding piece 43 each extend at a right angle with respect to the flat plate portion 41 from a position that is separated from the inner side of each of a pair of sides that extend in parallel by a second prescribed interval in one face of the flat plate portion 41. The flat plate portion 41 has a length of L on one side of the square shape of the outer shape, and a wall thickness of d that is the same as the wall thickness of the tubular member 70.

[0082] The "second prescribed interval" between each of the first holding piece 42 and the second holding piece 43 and the side of the flat plate portion 41 is set to be substantially the same as the wall thickness d' of the corner cylinder portion 11 in the first joint member 10, as in the case of the pair of link insertion pieces 23 of the second joint member 20. As shown in Fig. 3(a), the first holding piece 42 extends linearly from the flat plate portion 41. On the other hand, the second holding piece 43 is bent at a position at which it extends linearly at about half the length from the flat plate portion 41 to the front end of the first holding piece 42, toward the first holding piece 42, and then extends parallel to the first holding piece 42 toward the front end on the opposite side of the flat plate portion 41, and is overall crank-shaped. In the second holding piece 43, the distance between the extension of the outer surface on the flat plate portion 41 side and the outer surface on the front end side is substantially the same as the wall thickness of the first holding piece 42, with the bent position as a boundary. In addition, the length from the flat plate portion 41 to the front end of the first holding piece 42 is longer than the length from the flat plate portion 41 to the front end of the second holding piece 43.

[0083] On the first holding piece 42, a first claw portion 44 protruding from the front end toward the second holding piece 43 side and a first groove portion 45 recessed in the inner surface facing the second holding piece 43 are provided. The first groove portion 45 is provided in the vicinity of the front end in the central portion in the direction in which the first holding piece 42 extends. These first claw portion 44 and first groove portion 45 are provided in the direction orthogonal to the direction in which the first holding piece 42 extends from the flat plate portion 41 and the direction orthogonal to the direction in which the first holding piece 42 and the second holding piece 43 are spaced apart, over the entire length of the first holding piece 42.

[0084] On the second holding piece 43, a second claw portion 46, a second groove portion 47, and two inner protrusions 48 are provided. The second claw portion 46 protrudes from the front end of the second holding piece 43 toward the side opposite to the first holding piece 42. The second groove portion 47 is recessed in the outer surface on the side opposite to the first holding piece 42 in the portion in which the second holding piece 43 is bent like a crank toward the first holding piece 42. The two inner protrusions 48 protrude toward the first holding piece 42 in the vicinity of the front end of the second holding piece 43, and the two inner protrusions 48 are spaced apart in the direction in which the second holding piece 43 extends. The distance from the flat plate portion 41 to the center between the two inner protrusions 48 is a distance that is half the length in the Z direction of the angle cylinder portion 11 in the first engagement member. These second claw portion 46, second groove portion 47, and inner protrusions 48 extend over the entire length of the second holding piece 43. The extending direction is the direction orthogonal to the direction in which the second holding piece 43 extends from the flat plate portion 41 and the direction orthogonal to the direction in which the first holding piece 42 and the second holding piece 43 are spaced apart.

[0085] The first claw portion 44 of the third engagement member 40 is caught in the first recessed portion 33 of the second engagement member 20 or the second groove portion 47 of another third engagement member 40. In the first groove portion 45, the catching claw portion 32 of the second engagement member 20 or the second claw portion 46 of another third engagement member 40 is caught. The second claw portion 46 is caught in the second recessed portion 34 of the second engagement member 20 or the first groove portion 45 of another third engagement member 40. In the second groove portion 47, the first claw portion 44 of another third engagement member 40 is caught.

[0086] In addition, the third engagement member 40 has a plurality of protrusions 49 on the outer surfaces of the first holding piece 42 and the second holding piece 43, respectively. The plurality of protrusions 49 extend linearly in the same direction as the second claw portion 46, the second groove portion 47, and the inner protrusions 48, respectively. The plurality of protrusions 49 are provided continuously in the direction in which the first holding piece 42 and the second holding piece 43 extend. Furthermore, the protrusions 49 are not provided on the front end side in the second holding piece 43 compared to the portion in which the crank is bent.

[0087] This third joining member 40 is also manufactured from a metal extrusion, similar to the first and second joining members 20. In the third joining member 40, the Z direction, which is parallel to the flat plate portion 41 and perpendicular to the direction of separation between the first and second retaining pieces 42 and 43, is the extrusion direction. The X direction is perpendicular to the Z direction and parallel to the flat plate portion 41. The Y direction is perpendicular to the Z direction and perpendicular to the flat plate portion 41 (see Figure 3(d)).

[0088] The third joining member 40 is manufactured by an extrusion forming process, a cutting process and a cutting process. The extrusion forming process forms the outer shape shown in the main view of Figure 3 (a) into a certain cross-sectional shape to form a third extruded body EB3 extending in the extrusion direction (Z direction) (refer to Figure 3 (d)); the cutting process cuts the third extruded body EB3 along a plane (XY plane) orthogonal to the Z direction; and the cutting process cuts off a specified part of the cut body EB3' obtained by the cutting process.

[0089] In the cutting step, the third extruded body EB3 is cut from its end in the Z direction at a distance L. In the scraping step, portions of the cut body EB3', excluding the flat plate portion 41, are removed from both ends of the cut body EB3' in the Z direction. Specifically, the first retaining piece 42 and the second retaining piece 43 are removed from each end in the Z direction to a distance d' (the hatched area in Figure 3(e)).

[0090] Thus, the outer shape of the flat plate portion 41 is a square with one side length L. The length of each of the first holding piece 42 and the second holding piece 43 excluding the flat plate portion 41 in the Z direction is L-2d', which is the length of the square tube portion 11 fitted into the first joint member.

[0091] The fixing member 50, such as Figure 4 As shown, the device comprises a flat plate portion 51 having a rectangular, flat shape, and a head portion 52 disposed along one of the two short sides of the flat plate portion 51. The short side of the flat plate portion 51 opposite the head portion 52 is chamfered in a C-shape at both ends, tapering toward the short side. The head portion 52 is formed thicker than the flat plate portion 51.

[0092] In the fixing member 50, the length of the long side of the flat plate portion 51 is equal to the length L of one side of the square that represents the outer shape of the rectangular tube portion 11 of the first joining member when viewed from the Z direction. Furthermore, the length of the short side of the flat plate portion 51 (the length without the tapered portion) is equal to the length of the fixing slit 14 of the first joining member. Furthermore, the length of the short side of the flat plate portion 51 is equal to the distance between the facing fixing member retaining portion 28 of the second joining member 20. Furthermore, the thickness of the flat plate portion 51 is equal to the width of the fixing slit 14 in the Z direction. Furthermore, the thickness of the flat plate portion 51 is equal to the width of the groove (the distance between the two side walls that constitute the groove) in the fixing member retaining portion 28 of the second joining member 20.

[0093] This fixing member 50, like the first and second joining members 20, is also manufactured from a metal extruded body. Here, the direction along which the short sides of the flat plate portion 51 extend is the Z direction, the direction along which the thickness of the flat plate portion 51 extends is the X direction, and the direction along which the long sides of the flat plate portion 51 extend is the Y direction. The fixing member 50 is manufactured by an extrusion step in which the extruded body is formed with the Z direction as the extrusion direction; a cutting step in which the extruded body is cut along a plane perpendicular to the Z direction (the XY plane); and a cutting step in which a predetermined portion of the cut body obtained by the cutting step is removed (in this case, a C-shaped chamfer is performed).

[0094] Wedge member 60, such as Figure 5 As shown, the wedge member 60 is formed into a flat plate with a rectangular outer shape. The ends of one of its two short sides are chamfered in a C-shape, tapering toward the short side. The length of the long side of the wedge member 60 is equal to the length L of one side of the square that forms the outer shape of the orthogonal cross-section of the tubular member 70. The length of the short side of the wedge member 60 (the length of the portion without the taper) is equal to the length of the slit 75 in the tubular member 70. Furthermore, the length of the short side of the wedge member 60 is equal to the distance between the pair of wedge retaining portions 15 in each of the pair of first insert pieces 12 and the pair of first insert pieces 13. The thickness of the wedge member 60 is equal to the width of the slit 75 (the length of the tubular member 70 in the longitudinal direction). Furthermore, the thickness of the wedge member 60 is equal to the distance between the two inner protrusions 16 provided on each of the first insert pieces 12 and 13.

[0095] This wedge member 60 is also manufactured from an extrusion-molded body of metal, like the first and second joint members 20. Here, the direction in which the short side extends in the wedge member 60 is taken as the Z direction, the thickness direction is taken as the X direction, and the direction in which the long side extends is taken as the Y direction. The wedge member 60 is manufactured by an extrusion-molding process that forms an extrusion-molded body with the Z direction as the extrusion direction, a cutting process that cuts the extrusion-molded body that has been extrusion-molded from a plane (XY plane) orthogonal to the Z direction, and a cutting process that cuts (here, performs a C-shaped chamfering) a prescribed portion of the cut body obtained by the cutting process.

[0096] Next, the construction of the three-dimensional frame-shaped skeleton structure using the above-described respective members will be described mainly using Figure 6 Fig. 12(c). First, the construction of the corner portion (refer to Figure 7 ) will be described, which is a corner portion in the three-dimensional frame-shaped skeleton structure shown in Figure 6 , in which the tubular member 70 is joined in only one of the X, Y, and Z directions with the corner cylinder portion 11 as the center. In the case of constructing this corner portion, the tubular member 70, the L-shaped first joint member 10A, the second joint member 20, the third joint member 40, the fixing member 50, and the wedge member 60 are used. In addition, in the case of constructing the skeleton structure, if the first joint member is used in a direction in which the Z direction (extrusion direction) becomes the height direction, the construction work is easy to perform.

[0097] First, the first joint member 10A and the second joint member 20, which have one fixing slit 14, are joined. Specifically, with the first joint member 10A in a state in which the fixing slit 14 is in the direction that is on the upper side compared to the center in the height direction in the corner cylinder portion 11, the pair of link insertion pieces 23 of the second joint member 20 is inserted into the corner cylinder portion 11 from above, and the flat portion 21 is brought into contact with the corner cylinder portion 11. At this time, the direction in which the pair of link insertion pieces 23 are separated by a gap is the same as the direction in which the fixing slit 14 extends.

[0098] Next, the fixing member 50 is inserted into the fixing slit 14 of the corner cylinder portion 11 from the short side opposite to the head portion 52. The fixing member holding portions 28 provided on the pair of link insertion pieces 23 and the fixing slit 14 are made to correspond to each other in position as described above, so as shown in Fig. 8(a), the flat plate portion 51 of the fixing member 50 is held by being inserted between the grooves of the pair of fixing member holding portions 28. Since the pair of link insertion pieces 23 are pressed in the direction of being separated from each other by the flat plate portion 51 being inserted between the grooves of the pair of fixing member holding portions 28, the plurality of protrusions 36 provided on the outer surfaces of the pair of link insertion pieces 23 press the inner surface of the corner cylinder portion 11. Also, as described above, since the fixing member 50 is made to have a length in the longitudinal direction equal to the length L of one side of the square shape that is the outer shape of the corner cylinder portion 11, as shown in Fig. 8(b), the both ends of the fixing member 50 in the longitudinal direction are in a state of being inserted into the fixing slit 14. Therefore, the first engaging member 10A can be prevented from being pulled out of the second engaging member 20 by the frictional resistance of the inner surface of the corner cylinder portion 11 and the plurality of protrusions 36 and the mechanical coupling of the fixing slit 14 and the fixing member 50.

[0099] As described above, if the second engaging member 20 is engaged with the first engaging member 10A, the pair of second insertion pieces 22 of the second engaging member 20 are in a state of extending in the Z direction (here, upward). Also, in the state of the second engaging member 20 being inserted into the corner cylinder portion 11, a gap into which the second extension portion 31 or the first holding piece 42 can be inserted is formed between the inner surface of the corner cylinder portion 11 and the outer surface of the first extension portion 30.

[0100] Next, the third engaging member 40 is engaged with the corner cylinder portion 11. Specifically, the first holding piece 42 and the second holding piece 43 of the third engaging member 40 are inserted into the corner cylinder portion 11 from below, with the flat plate portion 41 abutting against the corner cylinder portion 11. At this time, since the second engaging member 20 is already engaged with the corner cylinder portion 11, the first extension portion 30 and the first holding piece 42 are made to face each other, and the second extension portion 31 and the second holding piece 43 are made to face each other.

[0101] In the third engaging member 40, if the first holding piece 42 and the second holding piece 43 are inserted into the corner cylinder portion 11, the outer surface of the first holding piece 42 and the outer surface of the flat plate portion 41 side in the second holding piece 43 compared with the crank portion are respectively in contact with the inner surface of the corner cylinder portion 11, and between the outer surface of the front end side in the second holding piece 43 compared with the crank portion and the inner surface of the corner cylinder portion 11, a gap into which the second extension portion 31 or the first holding piece 42 is inserted is formed. Further, in the second engaging member 20 and the third engaging member 40, the positional relationship of each is made to correspond between the locking claw portion 32 and the first groove portion 45, between the first recess portion 33 and the first claw portion 44, and between the second recess portion 34 and the second claw portion 46. Therefore, if the third engaging member 40 is engaged with the corner cylinder portion 11, the locking claw portion 32 is locked in the first groove portion 45, the first claw portion 44 is locked in the first recess portion 33, and the second claw portion 46 is locked in the second recess portion 34, whereby the third engaging member 40 can be prevented from being pulled out of the corner cylinder portion 11.

[0102] In the corner cylinder portion 11, in a state in which the second engaging member 20 and the third engaging member 40 are engaged respectively, a cube whose one side has a length L is formed by the four side surfaces of the corner cylinder portion 11, the flat surface portion 21, and the flat plate portion 41.

[0103] Next, by fitting the end portion of one tubular member 70 into each of the pair of first insertion pieces 12, the pair of first insertion pieces 13, and the pair of second insertion pieces 22, the tubular member 70 is engaged with the first engaging member 10A and the second engaging member 20 respectively. Here, the pair of first insertion pieces 12 is described as an example. At the front end of each of the first insertion pieces 12, an inclined projection 17 is formed which projects toward the corner cylinder portion 11. This inclined projection 17 is inclined outward from the front end of the first insertion piece 12, and thus guides the relative fitting of the first insertion piece 12 into the tubular member 70.

[0104] Further, if the tubular member 70 is fitted into the pair of first insertion pieces 12, the end portion of the tubular member 70 abuts against the corner cylinder portion 11. In this state, each side surface of the cube formed by the side surfaces of the corner cylinder portion 11, the flat surface portion 21, and the flat plate portion 41 and the corresponding side surface of the tubular member 70 are on the same plane, and a structure having a good appearance without steps therebetween is obtained. Further, because there are no steps between the engaging members and the tubular member 70, in the skeleton structure constructed, there is no danger that the arrangement to the arrangement surface becomes unstable or that a shake is generated.

[0105] If the tubular member 70 is inserted into the pair of first insertion pieces 12, the wedge member 60 is inserted into the slit 75 provided near the end portion of the tubular member 70. The wedge holding portion 15 provided on the pair of first insertion pieces 12 and the slit 75 are made to correspond in positional relationship as described above. Therefore, as shown in Fig. 8(b), the flat plate-shaped wedge member 60 is held between the pair of wedge holding portions 15 which are the gaps between the two inner projections 16, respectively. Further, as described above, because the length in the lengthwise direction of the wedge member 60 is made the same as the length L of one side of the square shape which is the outer shape of the tubular member 70, as shown in Fig. 8(a), the both end portions in the lengthwise direction of the wedge member 60 become the state of being inserted into the slit 75, respectively. Therefore, when an external force acts on the tubular member 70 into which the first insertion pieces 12 of the first joint member 10A are inserted, the danger of the first insertion pieces 12 being strained or longitudinally bent is prevented by the wedge member 60.

[0106] By being made as described above, the tubular member 70 whose axis direction is the X direction is jointed to the first joint member 10A. Also, with respect to the remaining pair of first insertion pieces 13 and the pair of second insertion pieces 22, as described above, the end portions of the respective tubular members 70 are inserted from the outside, and then the wedge member 60 is inserted into the slit 75 of the tubular member 70. Thereby, the tubular member 70 whose axis direction is the Y direction and the tubular member 70 whose axis direction is the Z direction are jointed to the first joint member 10A. That is, one L-shaped first joint member 10A and one second joint member 20 can joint one tubular member 70 whose axis direction is the X direction, one tubular member 70 whose axis direction is the Y direction, and one tubular member 70 whose axis direction is the Z direction to construct the corner portion in the skeletal structure of the three-dimensional frame shape.

[0107] In the construction of the skeletal structure of the three-dimensional frame shape, for example, by using the T-shaped first joint member 10B and the second joint member 20 shown in Figs. 10(a) and 10(b) together, one tubular member 70 whose axis direction is the X direction, two tubular members 70 whose axis direction is the Y direction, and one tubular member 70 whose axis direction is the Z direction can be jointed. Further, by using the cross-shaped first joint member 10C and the second joint member 20 shown in Figs. 11(a) and 11(b) together, two tubular members 70 whose axis direction is the X direction, two tubular members 70 whose axis direction is the Y direction, and one tubular member 70 whose axis direction is the Z direction can be jointed.

[0108] By combining the L-shaped first joint member 10A, the T-shaped first joint member 10B, and the cross-shaped first joint member 10C with one second joint member 20, respectively, the upper structure in the skeletal structure of the three-dimensional frame shape can be constructed (see Figs. 12(a) and 12(b)). Figure 6The upper part of the Figure 6 in the lower part).

[0109] Next, the portion where the two tubular members 70 are joined vertically with the axial direction being the Z direction in the three-dimensional frame-shaped skeleton structure (see Figure 6 The structure of the first joining member 10A' (i.e., the middle portion of the square tube 11) is primarily described using Figures 12(a) to 12(c). Figures 12(a) to 12(c) illustrate an L-shaped first joining member 10A' as an example. In this first joining member 10A', two fixing slits 14 are provided, spaced apart in the Z direction, on each of a pair of parallel side surfaces of the square tube 11. The two fixing slits 14 are symmetrically arranged with the center of the square tube 11 in the Z direction serving as the boundary. The remaining structure of the first joining member 10A' is identical to that of the first joining member 10A. The description of the joining of the tubular member 70 in the X and Y directions will be omitted.

[0110] This first joining member 10A' can join the second joining member 20 to both sides of the square tube 11 in the Z direction. Specifically, the pair of connecting inserts 23 of the second joining member 20 are inserted from above into the square tube 11 of the first joining member 10A', while the pair of connecting inserts 23 of the other second joining member 20 are inserted from below. Because the first and second extensions 30, 31 of the second joining member 20 have corresponding shapes as described above, the second extension 31 of the other second joining member 20 is inserted between the first extension 30 of one second joining member 20 and the inner surface of the square tube 11. The locking claw 32 at the tip of the first extension 30 of one second joining member 20 is locked in the second recess 34 of the other second joining member 20 (see Figure 12(c)). The locking claw 32 locked in the second recess 34 prevents the two second joining members 20 from being removed from the square tube 11.

[0111] After the pair of connecting inserts 23 of the second joining member 20 are inserted from above and below the square tube portion 11, the fixing members 50 are inserted into the two fixing slits 14 spaced apart vertically (in the Z direction). This, for the same reasons as above, joins the two second joining members 20 to the first joining member 10A', with the pair of second inserts 22 extending upward and downward from the square tube portion 11 (see Figure 12(b)). The ends of the tubular member 70 are then fitted over the pair of second inserts 22 extending upward and downward from the square tube portion 11, respectively. The wedge member 60 is then inserted into the slits 75 near the ends of the tubular member 70. This allows the two tubular members 70, whose axial direction is the Z direction, to be joined to the first joining member 10A'.

[0112] Further, by providing the fixing slits 14 at portions shown by dotted lines in FIG. 10(b) and FIG. 11(b) respectively, with respect to the first joint member 10B of the T shape and the first joint member 10C of the cross shape, the first joint member 10B' and the first joint member 10C' can be made respectively. Thereby, two tubular members 70 with the axial direction as the Z direction can be joined to the first joint member 10B' and the first joint member 10C' respectively.

[0113] Thus, in the joint member that joins a plurality of tubular members 70, by using the first joint member of a type corresponding to the direction and the number of the joined tubular members 70, a three-dimensional frame-shaped skeleton structure as shown in FIG. 12 can be constructed. Figure 6

[0114] Incidentally, the joint member of the present embodiment, by not joining the second joint member 20 to the first joint member, can construct a two-dimensional frame-shaped skeleton structure parallel to the XY plane, with the tubular members 70 joined to the first joint member only. In this case, two third joint members 40 are joined to the first joint member.

[0115] Specifically, as shown in FIG. 13(a) to FIG. 13(c), with respect to the first joint member 10A that has the axial direction of the corner cylinder portion 11 oriented in the up-down direction, the first holding piece 42 and the second holding piece 43 of the third joint member 40 are inserted into the corner cylinder portion 11 from above, and the first holding piece 42 and the second holding piece 43 of the other third joint member 40 are inserted into the corner cylinder portion 11 from below, so that the respective flat plate portions 41 abut against the corner cylinder portion 11. Thereby, a cube with one side of length L is formed by the four side surfaces of the corner cylinder portion 11, the flat plate portion 41 in the upper third joint member 40, and the flat plate portion 41 in the lower third joint member 40 (see FIG. 13(b)). Further, by joining the tubular member 70 to the first joint member 10A in this state, the respective side surfaces of the above-mentioned cube and the corresponding side surfaces of the tubular member 70 are on the same plane, and a structure with good appearance without steps between them is obtained. In addition, because there are no steps between the joint member and the tubular member 70, there is no risk that the setting of the skeleton structure to the setting surface becomes unstable or shakes.

[0116] ​In addition, because the first holding piece 42 and the second holding piece 43 of the third coupling member 40 are mutually corresponding shapes as described above, the first holding piece 42 of one of the third coupling members 40 is inserted between the outer surface of the crank portion on the front end side and the inner surface of the corner cylinder portion 11 of the other of the third coupling members 40. In addition, the first claw portion 44 of the front end of the first holding piece 42 of one of the third coupling members 40 is latched in the second groove portion 47 of the other of the third coupling members 40, and the second claw portion 46 of the front end of the second holding piece 43 of one of the third coupling members 40 is latched in the first groove portion 45 of the other of the third coupling members 40 (see FIG. 13(c)). With the latching of the first claw portion 44 and the second groove portion 47 and the latching of the second claw portion 46 and the first groove portion 45, the two third coupling members 40 can be prevented from being pulled out of the corner cylinder portion 11, respectively.

[0117] Further, the fixing member 50 can also be inserted into the fixing slit 14 of the first coupling member, and the opening of the fixing slit 14 can be buried.

[0118] Furthermore, by using a first coupling member of a type corresponding to the direction and number of the coupled tubular members 70, various two-dimensional frame-shaped skeleton structures can also be constructed.

[0119] The skeleton structure constructed in this way can be used for a variety of purposes such as a stand, a temporarily installed building, a skeleton of a greenhouse, a large advertising board, a frame of a sign, a trolley, and the like. The purpose is not particularly limited, but the skeleton structure is suitable for a purpose requiring high mechanical strength, high stability without strain or sway.

[0120] As described above, according to the present embodiment, if the second coupling member 20 is coupled to the first coupling member, and the fixing member 50 is inserted into the fixing slit 14, because the fixing member 50 is held in the fixing member holding portion 28, the relative movement of the second coupling member 20 with respect to the axial direction of the corner cylinder portion 11 can be prevented. Thus, compared to the conventional technology, the coupling strength of the first coupling member and the second coupling member 20 can be improved, and the coupling strength of the tubular member 70 in the axial direction as the X direction or the Y direction and the tubular member 70 in the axial direction as the Z direction can be improved. Therefore, a skeleton structure in which the coupling strength of the tubular members 70 to each other is high can be provided.

[0121] By the way, on the basis of a structure in which the length L of one side of the square shape of the outer shape of the tubular member 70 is made 40 mm, the wall thickness d of the tubular member 70 is made 2 mm, and the joining members and the tubular member 70 are made of an aluminum alloy for a stretch material, a test body in which the tubular member 70 is joined to the first joining member via the second joining member 20 was made. In a state in which the corner cylinder portion 11 of the test body was fixed, a cantilever bending test in which a load was applied in the X direction or the Y direction to a portion of the tubular member 70 at a prescribed position (80 mm in this case) in the Z direction from the corner cylinder portion 11 was performed. As a result, the maximum load until longitudinal bending was 3872 N in the X direction and 4607 N in the Y direction, and it was confirmed that sufficient joining strength could be obtained.

[0122] In addition, since the first joining member and the second joining member 20 can be joined by the insertion of the pair of second insertion pieces 22 with high joining strength, it is not necessary to perform a welding operation. In addition, since the welding operation is not necessary as described above, it is possible to construct the skeletal structure in an environment in which the welding operation is difficult. Furthermore, although the welding is not necessary in order to construct the skeletal structure of the present embodiment, it is not a structure in which the case of performing the welding is excluded.

[0123] Further, in the present embodiment, all of the members for joining to the tubular member 70, such as the first joining members (the L-shaped first joining member 10A, the T-shaped first joining member 10B, and the cross-shaped first joining member 10C), the second joining member 20, the third joining member 40, the fixing member 50, and the wedge member 60, are manufactured by extrusion molding, like the tubular member 70. Therefore, it is possible to form all of the structural elements of the skeletal structure from the same metal material. For example, it is possible to make all of the structural elements of the skeletal structure into a structure made of an aluminum alloy for a stretch material. Thus, it is possible to eliminate the conventional problem in which a strain is generated in the skeletal structure due to a difference in the thermal expansion rate between the members.

[0124] In addition, in the case in which the members are welded to each other, the composition of the portion in which the welding is performed can be different from the composition of the members, and there is a risk that a strain is generated in the skeletal structure due to a difference in the thermal expansion rate, but according to the present embodiment, since the welding operation is not necessary as described above, there is no risk of a strain due to the welding in the skeletal structure.

[0125] In addition, since it is possible to form all of the structural elements of the skeletal structure from the same metal material as described above, it is not necessary to perform a separate operation at the time of disposal, and further, the processing of the material for recycling is also easy.

[0126] In addition, in the present embodiment, the skeleton structure is constructed by embedding of the members, and small screws and bolts are not used at all. Therefore, electrolytic corrosion is effectively prevented.

[0127] The above describes suitable embodiments of the present application, but the present application is not limited to the above-described embodiments, and various modifications and designs can be made within the scope of the gist of the present application, as shown below.

[0128] For example, among the above, a case is exemplified in which the outer shape of the orthogonal cross section of the tubular member 70 is a square and the outer shape of the corner cylinder portion 11 in the first joint member as viewed from the Z direction is a square of the same size. In this case, as the tubular member 70 that is jointed in the X direction, the Y direction, and the Z direction, there is an advantage that a single kind of tubular member 70 can be used regardless of the direction. However, if it is decided to use a kind of tubular member 70 for each of the directions of jointing or the direction of jointing is taken into consideration, the outer shape of the orthogonal cross section of the tubular member 70 and the outer shape of the corner cylinder portion 11 of the first joint member as viewed from the Z direction can also be rectangular. In that case, the dimensions and shapes can also be set in a manner such that the side surfaces of the structural members of the skeleton structure are on the same plane.

Claims

1. A joining member comprising a first joining member, a second joining member and a fixing member, wherein: The first joining member comprises a square tube portion, a pair of first insertion pieces and a fixing slit. The corner tube portion is in the shape of a rectangular parallelepiped or a cube; The pair of first insertion pieces extend in the X direction or the Y direction perpendicular to the Z direction, respectively, on each of at least two of the four side faces of the square tube portion that are parallel to the Z direction, which is the axial direction, at a position spaced inward from each of a pair of side faces extending in the Z direction by a predetermined distance. The fixing slit penetrates each of a pair of opposing side surfaces in the above-mentioned square tube portion in the thickness direction for the above-mentioned fixing member to be inserted. The second joining member includes a flat surface, a pair of second insertion pieces, a pair of connecting insertion pieces, a holding protrusion, and a fixing member holding portion. The planar portion is a square or rectangular planar portion; The pair of second insertion pieces extend from the planar portion at right angles along each of a pair of side edges on one surface of the planar portion; The pair of connecting insert pieces extend from the plane portion at right angles along each of a pair of side edges on the surface of the plane portion opposite to the surface from which the second insert piece extends, and are inserted into the angled tube portion; The retaining protrusion protrudes from the inner surfaces of the pair of connecting inserts facing each other toward the other member; The fixing member holding portion is formed between the pair of holding protrusions and serves as a space for holding the fixing member.

2. A skeleton structure constructed by connecting tubular members, which are angle tubes, with a joint member comprising a first joint member, a second joint member, and a fixing member, wherein: The first joint member includes a square tube portion, a pair of first insertion pieces and a fixing slit. The corner tube portion is in the shape of a rectangular parallelepiped or a cube; The pair of first insertion pieces extend in the X direction or the Y direction perpendicular to the Z direction, respectively, on each of at least two of the four side faces of the square tube portion that are parallel to the Z direction, which is the axial direction, at a position spaced inward from each of a pair of side faces extending in the Z direction by a predetermined distance. The fixing slit penetrates each of a pair of opposing side surfaces in the above-mentioned square tube portion in the thickness direction for the above-mentioned fixing member to be inserted. The second joining member includes a flat surface, a pair of second insertion pieces, a pair of connecting insertion pieces, a holding protrusion, and a fixing member holding portion. The planar portion is a square or rectangular planar portion; The pair of second insertion pieces extend from the planar portion at right angles along each of a pair of side edges on one surface of the planar portion; The pair of connecting insert pieces extend from the plane portion at right angles along each of a pair of side edges on the surface of the plane portion opposite to the surface from which the second insert piece extends, and are inserted into the angled tube portion; The retaining protrusion protrudes from the inner surfaces of the pair of connecting inserts facing each other toward the other member; The fixing member holding portion is formed between the pair of holding protrusions as a space for holding the fixing member. The second joining member is fixed to the first joining member by inserting the pair of connecting insert pieces into the angled tube portion and holding the fixing member inserted into the fixing slit in the fixing member holding portion. The plurality of tubular members are joined by inserting the pair of first insertion pieces and the pair of second insertion pieces into the ends of different tubular members.

Images