FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. JOINING MEMBER AND FRAMEWORK STRUCTURE
2.
1.(A) A CO., LTD.
(B) Japan
(C) 376-3 Sato, Wanouchi-cho, Anpachi-gun, Gifu 5030234 Japan
The following specification particularly describes the invention and the manner in which it is to be
performed.
2
Technical Field
[0001]
The present invention relates to joining members for
joining tubular members to each other, and to framework
structures constructed by joining tubular members to each
other by using the joining members.
Background Art
[0002]
The present inventor has proposed joining members used
for joining tubular members, such as angular pipes, to each
other to construct a framework structure. Each joining
member has multiple insertion segments to which the tubular
members are externally fitted, and is manufactured by
extrusion-molding metal (Patent Literature 1).
[0003]
In Patent Literature 1, when a three-dimensional
framework structure is to be constructed, first joining
members and second joining members are used as the joining
members. Specifically, each first joining member includes a
base that is a solid cube and that has a hole extending
there through in the extrusion direction as a Z direction,
and first insertion segments extending from side surfaces of
the base in an X direction and a Y direction that are
orthogonal to the Z direction. By inserting the first
insertion segments of the first joining member into the end
of each tubular member, a two-dimensional-frame-like
framework structure in the X-Y direction can be constructed.
3
Each second joining member includes a protrusion extending
from a square planar portion, and second insertion segments
extending from a surface of the planar portion opposite from
the protrusion. The protrusion of the second joining member
is fitted into the hole in the first joining member, and the
second insertion segments are inserted into the
corresponding end of a tubular member, so that the tubular
member is erected perpendicularly to the two-dimensional-
frame-like framework structure, whereby a three-dimensional-
frame-like framework structure can be constructed.
[0004]
In the technology according to Patent Literature 1, the
first joining member and the second joining member (joining
members), in addition to the tubular members, can be formed
of extrusion-molded bodies, so that the tubular members and
the joining members can be composed of a metallic material
having the same composition. Accordingly, by using these
joining members, a framework structure with no possibility
of distortion occurring due to different thermal expansion
coefficients can be constructed.
[0005]
However, in the technology according to Patent
Literature 1, since the first joining member and the second
joining member are connected to each other by fitting the
protrusion into the hole, it is difficult to obtain
sufficient connection strength. Although it is conceivable
to weld the first joining member and the second joining
member together, this is problematic in that the welding
4
process is troublesome and that the environment where such a
process can be performed is limited.
Citation List
Patent Literature
[0006]
PTL 1: Japanese Unexamined Patent Application
Publication No. 2021-178330
Summary of Invention
Technical Problem
[0007]
In view of the circumstances described above, an object
of the present invention is to provide a joining member
capable of enhancing the joining strength between tubular
members, and a framework structure constructed by joining
the tubular members to each other by using the joining
member.
Solution to Problem
[0008]
In order to solve the aforementioned problems, a
joining member according to the present invention is
provided. The joining member includes a first joining
member, a second joining member, and a securing member. The
first joining member includes: a rectangular-parallelepiped
or cubical angular-pipe-like angular tube section; a pair of
first insertion segments extending from each of at least two
5
side surfaces of four side surfaces parallel to a Z
direction as an axial direction of the angular tube section,
the pair of first insertion segments extending in an X
direction or a Y direction orthogonal to the Z direction
from positions located inward by a predetermined distance
relative to a pair of side edges, extending in the Z
direction, of each of the at least two side surfaces; and a
securing slit that passes in a thickness direction through
each of an opposing pair of the side surfaces of the angular
tube section and to which the securing member is inserted.
The second joining member includes: a square or rectangular
planar portion; a pair of second insertion segments
extending perpendicularly from the planar portion
respectively along a pair of side edges of one of surfaces
of the planar portion; a pair of linkage insertion segments
extending perpendicularly from the planar portion
respectively along the pair of side edges of a surface
opposite the surface of the planar portion from which the
second insertion segments extend, the pair of linkage
insertion segments being inserted in the angular tube
section; and a securing member retainer provided between the
pair of linkage insertion segments and for retaining the
securing member therein.
[0009]
According to the joining member having this
configuration, after the pair of linkage insertion segments
are inserted into the angular tube section, the securing
member is inserted into the securing slit, and the securing
6
member is retained by the securing member retainer provided
between the pair of linkage insertion segments, so that the
first joining member and the second joining member can be
connected to each other. By joining the second joining
member to the first joining member, the pair of second
insertion segments extending from the planar portion of the
second joining member extend in the Z direction. Then, two
or more pairs of the first insertion segments and a pair of
the second insertion segments are relatively fitted to ends
of tubular members, so that at least two tubular members
with their axial direction as the X direction or the Y
direction can be connected to one tubular member with its
axial direction as the Z direction.
[0010]
In this joining member, the securing member inserted in
the securing slit provided in the corresponding side
surfaces of the angular tube section is retained by these
curing member retainer, so that relative movement of the
second joining member in the axial direction of the angular
tube section is prevented, and the first joining member and
the second joining member are mechanically connected to each
other. Accordingly, as compared with the related art in
which two joining members are connected to each other by
fitting the protrusion into the hole, the connection
strength between the first joining member and the second
joining member can be enhanced. Specifically, the connection
strength between a tubular member with its axial direction
as the X direction or the Y direction and a tubular member
7
with its axial direction as the Z direction can be enhanced.
Because the connection strength between the first joining
member and the second joining member can be enhanced, a
welding process for joining the two joining members to each
other can be made unnecessary, unlike the related art.
[0011]
A framework structure according to the present
invention is a framework structure constructed by joining
tubular members as angular pipes to each other by using a
joining member including a first joining member, a second
joining member, and a securing member. The first joining
member includes: a rectangular-parallelepiped or cubical
angular-pipe-like angular tube section; a pair of first
insertion segments extending from each of at least two side
surfaces of four side surfaces parallel to a Z direction as
an axial direction of the angular tube section, the pair of
first insertion segments extending in an X direction or a Y
direction orthogonal to the Z direction from positions
located inward by a predetermined distance relative to a
pair of side edges, extending in the Z direction, of each of
the at least two side surfaces; and a securing slit that
passes in a thickness direction through each of an opposing
pair of the side surfaces of the angular tube section and to
which the securing member is inserted. The second joining
member includes: a square or rectangular planar portion; a
pair of second insertion segments extending perpendicularly
from the planar portion respectively along a pair of side
edges of one of surfaces of the planar portion; a pair of
8
linkage insertion segments extending perpendicularly from
the planar portion respectively along the pair of side edges
of a surface opposite the surface of the planar portion from
which the second insertion segments extend, the pair of
linkage insertion segments being inserted in the angular
tube section; and a securing member retainer provided
between the pair of linkage insertion segments and for
retaining the securing member therein. The second joining
member is secured to the first joining member as a result of
the pair of linkage insertion segments being inserted in the
angular tube section and these curing member inserted in the
securing slit being retained by the securing member retainer.
A plurality of the tubular members are connected to each
other as a result of the pair of first insertion segments
and the pair of second insertion segments being inserted
into ends of the tubular members that are different from
each other.
[0012]
This is the configuration of a three-dimensional-frame-
like framework structure constructed by joining tubular
members to each other by using the aforementioned joining
member including the first joining member, the second
joining member, and the securing member. Accordingly, a
framework structure with higher connection strength between
the tubular members than in the related art can be provided.
Because the framework structure is constructed by the
engagement between the members, a welding process is not
necessary, so that the framework structure can be
9
constructed even in an environment where it is difficult to
perform the welding process.
Advantageous Effects of Invention
[0013]
Accordingly, the present invention can provide a
joining member capable of enhancing the connection strength
between tubular members, and a framework structure
constructed by joining the tubular members to each other by
using the joining member.
Brief Description of Drawings
[0014]
[Fig. 1] Fig. 1A is a plan view of an L-shaped first
joining member, Fig. 1B is a front view of the L-shaped
first joining member, Fig. 1C is a perspective view of the
L-shaped first joining member, and Fig. 1D illustrates a
method for manufacturing the L-shaped first joining member
from a first extrusion-molded body.
[Fig. 2] Fig. 2A is a front view of a second joining
member, Fig. 2B is a right side view of the second joining
member, Fig. 2C is a perspective view of the second joining
member, Fig. 2D illustrates a method for manufacturing the
second joining member from a second extrusion-molded body,
and Fig. 2E illustrates the method for manufacturing the
second joining member continuously from Fig. 2D.
[Fig. 3] Fig. 3A is a front view of a third joining
member, Fig. 3B is a right side view of the third joining
10
member, Fig. 3C is a perspective view of the third joining
member, Fig. 3D illustrates a method for manufacturing the
third joining member from a third extrusion-molded body, and
Fig. 3E illustrates the method for manufacturing the third
joining member continuously from Fig. 3D.
[Fig. 4] Fig. 4 is a perspective view of a securing
member.
[Fig. 5] Fig. 5 is a perspective view of a wedge member.
[Fig. 6] Fig. 6 is an exploded perspective view of a
three-dimensional-frame-like framework structure.
[Fig. 7] Fig. 7 is a partially enlarged perspective
view of an area indicated by an arrow A in Fig. 6.
[Fig. 8] Fig. 8A is a cross-sectional view taken along
a plane orthogonal to a Y direction at the center of an
angular tube section in Fig. 7, and Fig. 8B is a cross-
sectional view taken along a plane orthogonal to a Z
direction at the center of the securing member in Fig. 7.
[Fig. 9] Fig. 9 is an exploded perspective view of
components in Fig. 7 in a disassembled state.
[Fig. 10] Fig. 10A is a plan view of a T-shaped first
joining member, and Fig. 10B is a perspective view of the T-
shaped first joining member.
[Fig. 11] Fig. 11A is a plan view of a cross-shaped
first joining member, and Fig. 11B is a perspective view of
the cross-shaped first joining member.
[Fig. 12] Fig. 12A is an exploded perspective view of a
joining member including one first joining member and two
second joining members, Fig. 12B is a perspective view of
11
the joining member and illustrates an assembled state of Fig.
12A, and Fig. 12C is a cross-sectional view taken along a
plane orthogonal to the Y direction at the center of the
angular tube section of the joining member in Fig. 12B.
[Fig. 13] Fig. 13A is an exploded perspective view of a
joining member used in a two-dimensional-frame-like
framework structure, Fig. 13B is a perspective view of the
joining member and illustrates an assembled state of Fig.
13A, and Fig. 13C is a cross-sectional view taken along a
plane orthogonal to the Y direction at the center of the
angular tube section of the joining member in Fig. 13B.
Description of Embodiments
[0015]
Hereinafter, as specific embodiments of the present
invention, multiple types of joining members, a framework
structure constructed by using these joining members, and a
method for manufacturing these joining members will be
described with reference to the drawings.
[0016]
The framework structure according to this embodiment is
constructed by joining tubular members 70 to each other by
using joining members. Each tubular member 70 is an angular
pipe as an extrusion-molded body, and has a square outer
shape in cross section (referred to as "orthogonal cross
section" hereinafter) orthogonal to an axial direction. The
length of each edge of the square as the orthogonal-cross-
sectional outer shape will be defined as "L", and the wall
12
thickness of the tubular member 70 will be defined as "d"
(see Fig. 8A). Thus, the length of eachedge of a square as
an orthogonal-cross-sectional inner shape of the tubular
member 70is L - 2d.
[0017]
The tubular member 70includes slits 75 that are located
near both of the opposite ends and that extend in a
thickness direction through two parallel side surfaces of
the four side surfaces (see, for example, Fig. 9). The
slits 75extend in a direction orthogonal to the axial
direction of the tubular member 70, but do not pass through
the side surfaces in the directions. Each slit 75 is
manufactured by performing a drilling process through the
tubular member as an extrusion-molded body.
[0018]
In this embodiment, a first joining member, a second
joining member20, and a third joining member40 are used as
the joining members. Furthermore, for constructing the
framework structure, a securing member50 for securing each
first joining member and each second joining member20to each
other, and a wedge member60 for reinforcing the joining are
used.
[0019]
The first joining member in this embodiment includes
three types that are referred to as an L-shaped first
joining member 10A(see Fig. 1A), a T-shaped first joining
member10B(see Fig. 10A), and a cross-shaped first joining
member10C"(see Fig. 11) when they are to be distinguished
13
from one another, and that are simply collectively referred
to as first joining members when they are not to be
distinguished from one another. Although details will be
described later, the first joining member of any type
includes a type in which two parallel side surfaces of an
angular tube section 11 are each provided with one securing
slit 14 and a type (see Fig. 12A) in which the two parallel
side surfaces are each provided with two securing slits 14.
Therefore, there are a total of six types of first joining
members. When the types having different numbers of
securing slits 14are to be distinguished from each other,
the types provided with one securing slit 14will be given
the same reference signs as above, whereas the types
provided with two securing slits 14will be referred to as an
L-shaped first joining member10A', a T-shaped first joining
member10B', and a cross-shaped first joining member10C'.
[0020]
The first joining member of any type includes an
angular-pipe-like angular tube section 11. In the first
joining member, the axial direction of the angular tube
section 11will be referred to as a Z direction, and the two
directions orthogonal to the Z direction will respectively
be referred to as an X direction and a Y direction.
[0021]
In addition to the angular tube section 11, the first
joining member includes a pair or two pairs of first
insertion segments 12, a pair or two pairs of first
insertion segments 13, and the securing slits14. Each of
14
the first insertion segments 12 and 13 is constituted of a
pair of members extending in the same direction from one of
four side surfaces of the angular tube section 11. The pair
of first insertion segments 12extend in the X direction from
the corresponding side surface of the angular tube section
11 from positions located inward by a predetermined distance
relative to a pair of side edges extending in the Z
direction. The pair of first insertion segments 13extendin
the Y direction from the corresponding side surface of the
angular tube section 11 from positions located inward by the
predetermined distance relative to a pair of side edges
extending in the Z direction. The securing slits14 extend
in the thickness direction through two parallel side
surfaces of the angular tube section 11. The L-shaped first
joining member 10Aincludes a pair of the first insertion
segments 12and a pair of the first insertion segments 13.
The T-shaped first joining member 10B includes a pair of
either of the first insertion segments 12 and the first
insertion segments 13 and two pairs of the other. The
cross-shaped first joining member 10C includes two pairs of
the first insertion segments 12 and two pairs of the first
insertion segments 13.
[0022]
As viewed from the Z direction, the angular tube
section 11 of the first joining member has a square outer
shape and a square inner shape. The length of each edge of
the square outer shape is L. Assuming that the wall
thickness of the angular tube section 11 is defined as d'
15
(see Fig. 8A), the length of each edge of the square inner
shape is L - 2d'. The wall thickness d' of the angular tube
section 11 is larger than the wall thickness d of the
tubular member 70. Therefore, the outer shape of the
angular tube section 11 as viewed from the Z direction has
the same size as the orthogonal-cross-sectional outer shape
of the tubular member 70, whereas the inner shape of the
angular tube section 11 as viewed from the Z direction is
smaller than the orthogonal-cross-sectional inner shape of
the tubular member 70.
[0023]
The pair of first insertion segments 12 and the pair of
first insertion segments 13ofthefirst joining member each
extend "from positions located inward by a predetermined
distance" relative to the corresponding pair of side edges
extending in the Z direction of the angular tube section 11.
This "predetermined distance" is set substantially equal to
the wall thickness d of the tubular member 70.
[0024]
The securing slits 14 in the first joining member are
long holes that extend along the corresponding side surfaces
of the angular tube section 11 and that are long in a
direction orthogonal to the Z direction. The securing slits
14 provided in two parallel side surfaces of the angular
tube section 11 are provided at identical positions in the Z
direction and are provided at positions offset toward one
side relative to the center of the angular tube section 11
in the Z direction. The securing member 50 is inserted
16
(fitted) into the securing slits 14. The two securing slits
14 provided in the parallel side surfaces have different
widths in the Z direction. One of the widths is equal to
the thickness of a flat plate portion 51, to be described
later, of the securing member 50, whereas the other width is
equal to the thickness of a head52 of the securing member 50.
[0025]
The first joining member includes a wedge retainer 15
for retaining the wedge member 60 between counterparts
forming a pair in each of the pair of first insertion
segments 12 and the pair of first insertion segments 13.
Specifically, in the first joining member, the pair of first
insertion segments 12 and the pair of first insertion
segments 13each have inner surfaces that face each other and
that are each provided with two inner protrusions 16
protruding toward the counterpart. The inner protrusions 16
extend along the entire length of each of the first
insertion segments 12 and 13 in the Z direction. The
positions of the inner protrusions 16 in the first insertion
segments 12 and 13 are set such that the inner protrusions
16 provided on one of the insertion segments of each pair
directly face the inner protrusions 16 provided on the other
insertion segment of the pair. The inner surface of each of
the first insertion segments 12 and 13 is recessed between
the two inner protrusions 16 than other areas. The four
inner protrusions 16 constitute the wedge retainer 15serving
as a gap for receiving and retaining the wedge member
60betweenthe pair of first insertion segments 12, as well as
17
between the pair of first insertion segments 13. The
distance from the angular tube section 11 to the center of
the wedge retainer 15 is equal to the distance from the end
of thetubular member 70 to the center of the slit 75.
[0026]
The first joining member includes an inclined
protrusion17provided near the distal end of the outer
surface of each of the pair of first insertion segments 12
and the pair of first insertion segments 13, and multiple
outer protrusions 18 provided at the outer surface of each
of the pair of first insertion segments 12 and the pair of
first insertion segments 13. The inclined protrusion17 is
inclined outward from the distal end of each of the first
insertion segments12 and 13 toward the angular tube section
11 at the distal side of the outer surface relative to the
wedge retainer 15. The multiple outer protrusions 18
protrude outward from the outer surface of each of the first
insertion segments 12 and 13 at the angular tube section 11
side relative to the wedge retainer 15. The direction in
which the multiple outer protrusions 18 are arranged is the
direction in which each of the first insertion segments 12
and 13 extends. The inclined protrusion17 and the outer
protrusions 18 extend along the entire length of each of the
first insertion segments 12 and 13 in the Z direction.
[0027]
The first joining members 10A, 10B, and 10C of the
respective types are each manufactured by performing an
extrusion-molding step for obtaining a metallic extrusion-
18
molded body, a cutting step for cutting the extrusion-molded
body along a plane orthogonal to the extrusion direction,
and a removing step for removing a predetermined part from a
cut body obtained in the cutting step.
[0028]
In the L-shaped first joining member 10A, as shown in
Fig. 1D, a pair of the first insertion segments 12extend in
the X direction from one of the four side surfaces of the
angular tube section 11, and a pair of the first insertion
segments 13extend in the Y direction from a neighboring one
of the side surfaces.
[0029]
The L-shaped first joining member10A is manufactured by
cutting a first extrusion-molded body EB1 (see Fig. 1D),
which extends in the Z direction (extrusion direction) while
having the shape in the plan view shown in Fig. 1Aas a fixed
cross-sectional shape, along a plane (XY plane, that is, a
plane indicated by a single-dot chain line in Fig. 1D)
orthogonal to the Z direction, and subsequently performing a
removing step to form the securing slits 14 in the two
parallel side surfaces of the angular tube section 11. The
cutting step involves performing cutting at a position where
the distance in the Z direction from the end of the first
extrusion-molded body EB1 is L - 2d.
[0030]
The second joining member 20 according to this
embodiment includes a planar portion 21 that is tabular and
square, a pair of second insertion segments 22, and a pair
19
of linkage insertion segments 23. The pair of second
insertion segments 22extend perpendicularly to the planar
portion 21from positions located inward by a predetermined
distance relative to a pair of parallel side edges of one of
the surfaces of the planar portion 21. The pair of linkage
insertion segments 23extendperpendicularly to the planar
portion 21 from positions located inward by a second
predetermined distance relative to a pair of side edges of
the surface opposite the surface of the planar portion 21
from which the second insertion segments 22extend.
[0031]
The planar portion 21 has a length L at each edge of
the square outer shape, and has a thickness d that is equal
to the wall thickness of the tubular member 70. The pair of
second insertion segments 22 are provided at the positions
located inward by the predetermined distance relative to the
pair of side edges of the planar portion 21. This
"predetermined distance" is set substantially equal to the
wall thickness d of the tubular member 70, similarly to the
"predetermined distance" of the pair of first insertion
segments 12 and the pair of first insertion segments 13of
the first joining member. On the other hand, the pair of
linkage insertion segments 23 are provided at the positions
located inward by the second predetermined distance relative
to the pair of side edges of the planar portion 21. This
"second predetermined distance" is set substantially equal
to the wall thickness d' of the angular tube section 11 of
the first joining member. The pair of side edges from which
20
the pair of linkage insertion segments 23 are separated by
the second predetermined distance are the same as the pair
of side edges from which the pair of second insertion
segments 22 are separated by the predetermined distance.
The pair of linkage insertion segments 23 extend from the
planar portion 21 by different lengths.
[0032]
Similar to thefirst insertion segments 12 and 13 of the
first joining member, the second joining member 20 includes
a wedge retainer 24 for retaining the wedge member 60
between the pair of second insertion segments 22. The wedge
retainer 24 of the second joining member 20 is constituted
of four inner protrusions 25. The inner protrusions 25 have
a configuration similar to that of the inner protrusions
16constituting the wedge retainer 15 at each of the first
insertion segments 12 and 13.
[0033]
The second joining member 20includes an inclined
protrusion26provided near the distal end of the outer
surface of each of the pair of second insertion segments 22,
and multiple outer protrusions 27 provided at the outer
surfaceof each of the pair of second insertion segments 22.
The inclined protrusions 26 and the outer protrusions 27
have configurations similar to those of the inclined
protrusions 17 and the outer protrusions 18 of the first
joining member.
[0034]
Furthermore, the second joining member 20 includes a
21
securing member retainer28 for retaining the securing member
50 between the pair of linkage insertion segments 23. In
detail, retaining protrusions 29 protrude toward
counterparts from the opposing inner surfaces of the pair of
linkage insertion segments23. The pair of retaining
protrusions 29 each have a groove at the distal end surface
thereof. The pair of retaining protrusions 29 are provided
to directly face each other. In the second joining member
20, the securing member retainer 28 serving as a gap for
receiving and retaining the securing member 50 is provided
between the grooves at the distal end surfaces of the pair
of retaining protrusions 29. The distance from the planar
portion 21 to the center of the securing member retainer 28
is equal to the distance from the end of the angular tube
section 11 in the Z direction to the center of each securing
slit 14.
[0035]
Of the pair of linkage insertion segments 23, the
linkage insertion segment 23 with the shorter extending
length from the planar portion 21 has a distal-end part
located relative to the retaining protrusion 29 and serving
as a first extending portion 30. The linkage insertion
segment 23 with the longer extending length from the planar
portion 21 has a distal-end part located relative to the
retaining protrusion 29 and serving as a second extending
portion 31. The outer surface of the first extending
portion 30 is located inward relative to an extension
surface of the outer surface in the other part of the
22
linkage insertion segment 23provided with the first
extending portion 30. The outer surface of the second
extending portion 31 is located on an extension surface of
the outer surface in the other part of the linkage insertion
segment 23provided with the second extending portion 31.
The distance from the outer surface of the first extending
portion 30 to the extension surface of the outer surface in
the other part of the linkage insertion segment 23 is equal
to the thickness of the second extending portion 31.
[0036]
The linkage insertion segment 23 having the first
extending portion 30is provided with a lock claw 32 and a
first recess 33. The lock claw 32 protrudes outward from
the distal end of the first extending portion 30. The first
recess 33is recessed from the outer surface of the linkage
insertion segment 23 at the planar portion 21 side relative
to the boundary between the retaining protrusion 29 and the
first extending portion 30. The first recess 33 is recessed
inward relative to the outer surface of the first extending
portion 30, and a first claw 44 of the third joining member
40, to be described later, is locked to the first recess 33.
[0037]
The linkage insertion segment 23 having the second
extending portion 31 is provided with a second recess 34.
The second recess 34 is recessed from the inner surface at
the second extending portion 31 side relative to the
boundary between the retaining protrusion 29 and the second
extending portion 31. The lock claw 32 or a second claw 46
23
of the third joining member 40, to be described later, is
locked to the second recess 34.
[0038]
Furthermore, the second joining member 20 includes a
base 35 and multiple protrusions 36. The base 35 is tabular,
is in contact with the planar portion 21, and connects the
pair of linkage insertion segments 23 to each other. The
protrusions 36 are provided on the outer surfaces of the
pair of linkage insertion segments 23. The base 35
reinforces the planar portion 21 and the base ends of the
pair of linkage insertion segments 23. Each of the multiple
protrusions 36 protrudes linearly in a direction orthogonal
to the direction in which the corresponding linkage
insertion segment 23extends from the planar portion 21. The
direction in which the protrusions 36 are arranged is the
direction in which the linkage insertion segments23 extend.
The protrusions 36 are not provided on the outer surface of
the first extending portion 30.
[0039]
Similar to the first joining member, the second joining
member 20 is manufactured from a metallic extrusion-molded
body. In the second joining member 20, a direction parallel
to the planar portion 21 and orthogonal to the direction in
which the pair of second insertion segments 22 are separated
from each other will be defined as the Z direction as the
extrusion direction. A direction orthogonal to the Z
direction and parallel to the planar portion 21 will be
defined as the X direction. A direction orthogonal to the Z
24
direction and perpendicular to the planar portion 21 will be
defined as the Y direction (see Fig. 2D).
[0040]
The second joining member 20 is manufactured by
performing an extrusion-molding step for forming a second
extrusion-molded body EB2 (see Fig. 2D), which extends in
the extrusion direction (Z direction) while having the outer
shape shown in the front view in Fig. 2A as a fixed cross-
sectional shape, a cutting step for cutting the second
extrusion-molded body EB2 along a plane (XY plane)
orthogonal to the Z direction, and a removing step for
removing a predetermined part of a cut body EB2' obtained in
the cutting step.
[0041]
The cutting step involves performing cutting at a
position of the distance L in the Z direction from the end
of the second extrusion-molded body EB2. The removing step
involves removing predetermined regions (shaded regions in
Fig. 2E), excluding the planar portion 21, at opposite ends
of the cut body EB2' in the Z direction. In detail, for the
pair of second insertion segments 22, the regions from the
opposite ends thereof in the Z direction to the distance d
are removed. For the pair of linkage insertion segments 23
and the base 35, the regions from the opposite ends thereof
in the Z direction to the distance d' are removed.
[0042]
Accordingly, the outer shape of the planar portion
21becomes a square with each edge having the length L. The
25
length of the pair of second insertion segments 22 in the Z
direction becomes L - 2d, which is the length to be fitted
to the end of the tubular member 70. Moreover, the length
of the pair of linkage insertion segments 23 and the base 35
in the Z direction becomes L - 2d', which is the length to
be fitted into the angular tube section 11 of the first
joining member.
[0043]
The third joining member 40 according to this
embodiment includes a flat plate portion 41 having a square
outer shape, and a first retaining segment 42 and a second
retaining segment 43 extending from the flat plate portion
41. The first retaining segment 42 and the second retaining
segment 43extendperpendicularly to the flat plate portion 41
from positions located inward by a second predetermined
distance relative to a pair of parallel side edges of one of
the surfaces of the flat plate portion 41. The flat plate
portion 41 has a length L at each edge of the square outer
shape, and has a thickness d that is equal to the wall
thickness of the tubular member 70.
[0044]
Similar to the case of the pair of linkage insertion
segments 23 of the second joining member 20, the "second
predetermined distance" between each of the first retaining
segment 42 and the second retaining segment 43 and the
corresponding side edge of the flat plate portion 41is set
substantially equal to the wall thickness d' of the angular
tube section 11 of the first joining member. As shown in
26
Fig. 3A, the first retaining segment 42extends linearly from
the flat plate portion 41. On the other hand, the second
retaining segment 43 entirely has a cranked shape such that
the second retaining segment 43extends linearly from the
flat plate portion 41 to a position located at about half
the length of the first retaining segment 42, bends toward
the first retaining segment 42 at that position, and
subsequently extends parallel to the first retaining segment
42 to the distal end toward the opposite side of the flat
plate portion 41. With the bent area of the second
retaining segment 43 as the boundary, the distance between
the extension surface of the outer surface at the flat plate
portion 41 side and the outer surface at the distal side is
substantially equal to the wall thickness of the first
retaining segment 42. The length from the flat plate
portion 41 to the distal end of the first retaining segment
42 is greater than the length from the flat plate portion 41
to the distal end of the second retaining segment 43.
[0045]
The first retaining segment 42 is provided with a first
claw 44 protruding from the distal end toward the second
retaining segment 43, and is also provided with a first
groove 45 recessed in the inner surface facing the second
retaining segment 43. The first groove 45 is provided at
the distal end side relative to the center in the extending
direction of the first retaining segment 42. The first claw
44 and the first groove 45 extend orthogonally to the
extending direction of the first retaining segment 42 from
27
the flat plate portion 41, and also extend along the entire
length of the first retaining segment 42 in a direction
orthogonal to the direction in which the first retaining
segment 42 and the second retaining segment 43 are separated
from each other.
[0046]
The second retaining segment 43 is provided with a
second claw 46, a second groove 47, and two inner
protrusions 48. The second claw 46 protrudes toward the
opposite side of the first retaining segment 42 from the
distal end of the second retaining segment 43. In the area
where the second retaining segment 43 bends in a cranked
fashion toward the first retaining segment 42, the second
groove 47 is recessed from the outer surface at the opposite
side of the first retaining segment 42. The two inner
protrusions 48 protrude toward the first retaining segment
42 near the distal end of the second retaining segment 43,
and are separated from each other in the extending direction
of the second retaining segment 43. 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 of the
angular tube section 11 of the first joining member in the Z
direction. The second claw 46, the second groove 47, and
the inner protrusions 48 extend along the entire length of
the second retaining segment 43. The extending direction
thereof is orthogonal to the direction in which the second
retaining segment 43extends from the flat plate portion 41,
and is also orthogonal to the direction in which the first
28
retaining segment 42 and the second retaining segment 43 are
separated from each other.
[0047]
The first claw 44 of the third joining member 40 is
locked to the first recess 33 of the second joining member
20 or to the second groove 47 of another third joining
member 40. The lock claw 32 of the second joining member 20
or the second claw 46 of another third joining member 40 is
locked to the first groove 45. The second claw 46 is locked
to the second recess 34 of the second joining member 20 or
the first groove 45 of another third joining member 40. The
first claw 44 of another third joining member 40 is locked
to the second groove 47.
[0048]
The third joining member 40 includes multiple
protrusions 49 on the outer surface of each of the first
retaining segment 42 and the second retaining segment 43.
The multiple protrusions 49 extend linearly in the same
direction as the second claw 46, the second groove 47, and
the inner protrusions 48. The direction in which the
multiple protrusions 49 are arranged is the direction in
which the first retaining segment 42 and the second
retaining segment 43 extend. In the second retaining
segment 43, the protrusions 49 are not provided toward the
distal end relative to the cranked area.
[0049]
Similar to the first joining member and the second
joining member 20, the third joining member 40 is also
29
manufactured from a metallic extrusion-molded body. In the
third joining member 40, a direction parallel to the flat
plate portion 41 and orthogonal to the direction in which
the first retaining segment 42 and the second retaining
segment 43 are separated from each other will be defined as
the Z direction as the extrusion direction. A direction
orthogonal to the Z direction and parallel to the flat plate
portion 41 will be defined as the X direction. A direction
orthogonal to the Z direction and perpendicular to the flat
plate portion 41 will be defined as the Y direction (see Fig.
3D).
[0050]
The third joining member 40is manufactured by
performing an extrusion-molding step for forming a third
extrusion-molded body EB3 (see Fig. 3D), which extends in
the extrusion direction (Z direction) while having the outer
shape shown in the front view in Fig. 3A as a fixed cross-
sectional shape, a cutting step for cutting the third
extrusion-molded body EB3 along a plane (XY plane)
orthogonal to the Z direction, and a removing step for
removing a predetermined part of a cut body EB3' obtained in
the cutting step.
[0051]
The cutting step involves performing cutting at a
position of the distance L in the Z direction from the end
of the third extrusion-molded body EB3. The removing step
involves removing parts, excluding the flat plate portion 41,
at opposite ends of the cut body EB3' in the Z direction.
30
In detail, in each of the first retaining segment 42 and the
second retaining segment 43, the regions (i.e., shaded
regions in Fig. 3E) from the opposite ends thereof in the Z
direction to the distance d' are removed.
[0052]
Accordingly, the outer shape of the flat plate portion
41 becomes a square with each edge having the length L. The
length, in the Z direction, of each of the first retaining
segment 42 and the second retaining segment 43 excluding the
flat plate portion 41 becomes L - 2d', which isthe length to
be fitted into the angular tube section 11 of thefirst
joining member.
[0053]
As shown in Fig. 4, the securing member 50 includes a
flat plate portion 51 that has a rectangular outer shape and
that is tabular, and also includes a head 52 provided along
one of short edges of the flat plate portion 51. With
regard to the flat plate portion 51, the opposite ends of
the short edge opposite the head 52are chamfered such that
the flat plate portion 51 is tapered toward the short edge.
The head 52 has a larger wall thickness than that of the
flat plate portion 51.
[0054]
In the securing member 50, the length in the direction
in which the long edges of the flat plate portion 51 extend
is equal to the length L of each edge of the square outer
shape when the angular tube section 11 of the first joining
member is viewed from the Z direction. The length of each
31
short edge of theflat plate portion 51 (i.e., the length of
the non-tapered part) is equal to the length of eachsecuring
slit 14in the first joining member. The length of each
short edge of theflat plate portion 51 is equal to the
distance between the securing member retainers 28 facing
each other in the second joining member 20. Furthermore,
the thickness of theflat plate portion 51 is equal to the
width of eachsecuring slit 14 in the Z direction. The
thickness of the flat plate portion 51 is equal to the width
of the groove (i.e., the distance between two sidewalls
constituting the groove) in thesecuring member retainer 28
of the second joining member 20.
[0055]
Similar to thefirst joining member and the second
joining member 20, the securing member 50 is also
manufactured from a metallic extrusion-molded body. The
direction in which the short edges of theflat plate portion
51 extend will be defined as the Z direction, the thickness
direction of the flat plate portion 51 will be defined as
the X direction, and the direction in which the long edges
of the flat plate portion 51 extend will be defined as the Y
direction. The securing member 50 is manufactured by
performing an extrusion-molding step for forming an
extrusion-molded body with the Z direction as the extrusion
direction, a cutting step for cutting the extrusion-molded
body along a plane (XY plane) orthogonal to the Z direction,
and a removing step (in this case,chamfering) for removing a
predetermined part of a cut body obtained in the cutting
32
step.
[0056]
As shown in Fig. 5, thewedge member 60has a rectangular
outer shape and is tabular. With regard to the wedge member
60, the opposite ends of one of the two short edges are
chamfered such that thewedge member 60 is tapered toward the
short edge. In the wedge member 60, the length in the
direction in which the long edges extend is equal to the
length L of each edge of the square as the orthogonal-cross-
sectional outer shape of thetubular member 70. The length
of each short edge of thewedge member 60 (i.e., the length
of the non-tapered part) is equal to the length of eachslit
75 in the tubular member 70. The length of each short edge
of thewedge member 60 is equal to the distance between the
pair of wedge retainers 15 in each of the pair of first
insertion segments 12 and the pair of first insertion
segments 13. The thickness of the wedge member 60 is equal
to the width of eachslit 75 (i.e., the length of the tubular
member 70 in the longitudinal direction). The thickness of
the wedge member 60 is equal to the distance between the two
inner protrusions 16 provided on each of the first insertion
segments 12 and 13.
[0057]
Similar to the first joining member and the second
joining member 20, the wedge member 60is also manufactured
from a metallic extrusion-molded body. The direction in
which the short edges of thewedge member 60 extend will be
defined as the Z direction, the thickness direction thereof
33
will be defined as the X direction, and the direction in
which the long edges thereof extend will be defined as the Y
direction. The wedge member 60 is manufactured by
performing an extrusion-molding step for forming an
extrusion-molded body with the Z direction as the extrusion
direction, a cutting step for cutting the extrusion-molded
body along a plane (XY plane) orthogonal to the Z direction,
and a removing step (in this case,chamfering) for removing a
predetermined part of a cut body obtained in the cutting
step.
[0058]
Next, the construction of a three-dimensional-frame-
like framework structure using the above-described
components will be described by mainly using Fig. 6 to Fig.
12C. First, in the three-dimensional-frame-like framework
structureshown in Fig. 6, the construction of a corner area
(see Fig. 7) where each tubular member70is connectedin only
one direction with respect to each of the X direction, the Y
direction, and the Z direction with reference to the angular
tube section 11 of thefirst joining memberwill be described.
When this corner area is to be constructed, tubular members
70, an L-shaped first joining member 10A, a second joining
member 20, a third joining member 40, a securing member 50,
and wedge members 60 are used. When the framework structure
is to be constructed, the construction process can be
performed readily by using thefirst joining memberoriented
such that the Z direction (extrusion direction) thereof is
aligned with the height direction.
34
[0059]
First, the first joining member10A having one securing
slit 14 and the second joining member 20 are connected to
each other. In detail, in a state where the first joining
member10A is oriented such that the securing slit14is
positioned higher than the center of the angular tube
section 11 in the height direction, the pair of linkage
insertion segments 23 of the second joining member 20 are
inserted into the angular tube section 11 from above, so
asto bring the planar portion 21 into abutment with the
angular tube section 11. In this state, the direction in
which the pair of linkage insertion segments 23 are
separated from each other is aligned with the extending
direction of the securing slit14.
[0060]
Subsequently, the securing member 50 is inserted into
the securing slit14 in the angular tube section 11, starting
from the short edge opposite the head 52. Since the
securing member retainer28 provided at the pair of linkage
insertion segments 23 and the securing slit14 correspond
with each other to have the positional relationship
described above, the flat plate portion 51 of the securing
member 50 is fitted and retained between the pair of grooves
of the securing member retainer28, as shown in Fig. 8A.
With the flat plate portion 51 being fitted between the pair
of grooves of the securing member retainer28, the pair of
linkage insertion segments 23 are pressed away from each
other, so that the multiple protrusions 36 provided on the
35
outer surfaces of the pair of linkage insertion segments 23
press against the inner surfaces of the angular tube section
11. As mentioned above, the length of the securing member
50 in the longitudinal direction is equal to the length L of
each edge of the square outer shape of the angular tube
section 11, so that the opposite longitudinal ends of the
securing member 50 are inserted in the securing slit14, as
shown in Fig. 8B. Therefore, with the frictional resistance
between the inner surfaces of the angular tube section 11
and the multiple protrusions 36and the mechanical linkage
between the securing slit14 and the securing member 50, the
second joining member 20 is prevented from pulling out of
the first joining member10A.
[0061]
As described above, when the second joining member 20
is connected to the first joining member 10A, the pair of
second insertion segments 22 of the second joining member 20
extend in the Z direction (in this case, upward). In the
state where the second joining member 20 is inserted in the
angular tube section 11, a gap capable of receiving the
second extending portion 31 or the first retaining segment
42 is formed between the corresponding inner surface of the
angular tube section 11 and the outer surface of the first
extending portion 30.
[0062]
Subsequently, the third joining member 40 is connected
to the angular tube section 11. In detail, the first
retaining segment 42 and the second retaining segment 43 of
36
the third joining member 40 are inserted into the angular
tube section 11 from below, so as to bring the flat plate
portion 41 into abutment with the angular tube section 11.
In this state, since the second joining member 20 is already
connected to the angular tube section 11, the first
extending portion 30 and the first retaining segment 42 are
set to face each other, and the second extending portion 31
and the second retaining segment 43 are set to face each
other.
[0063]
In the third joining member 40, when the first
retaining segment 42 and the second retaining segment 43 are
inserted into the angular tube section 11, the outer surface
of the first retaining segment 42 and the outer surface at
the flat plate portion 41 side relative to the cranked area
of the second retaining segment 43 respectively come into
contact with the inner surfaces of the angular tube section
11, and a gap capable of receiving the second extending
portion 31 or the first retaining segment 42 is formed
between the outer surface at the distal side relative to the
cranked area of the second retaining segment 43 and the
corresponding inner surface of the angular tube section 11.
The second joining member 20 and the third joining member 40
correspond with each other to have respective positional
relationships between the lock claw 32 and the first groove
45, between the first recess 33 and the first claw 44, and
between the second recess 34 and the second claw 46.
Therefore, when the third joining member 40 is connected to
37
the angular tube section 11, the lock claw 32 becomes locked
to the first groove 45, the first claw 44 becomes locked to
the first recess 33, and the second claw 46 becomes locked
to the second recess 34, whereby the third joining member 40
is prevented from pulling out of the angular tube section 11.
[0064]
In the state where the second joining member 20 and the
third joining member 40 are connected to the angular tube
section 11, the four side surfaces of the angular tube
section 11, the planar portion 21, and the flat plate
portion 41constitute a cube with each edge having the length
L.
[0065]
Subsequently, the end of each tubular member 70 is
externally fitted to the corresponding one of the pair of
first insertion segments 12, the pair of first insertion
segments 13, and the pair of second insertion segments 22,
thereby joining the tubular members 70 respectively to the
first joining member10A and the second joining member 20.
The following description relates to the pair of first
insertion segments 12 as an example. The distal ends of the
first insertion segments 12 have the inclined protrusions 17
protruding toward the angular tube section 11. Because the
inclined protrusions 17 are inclined outward from the distal
ends of the first insertion segments 12, the first insertion
segments 12 are guided to be relatively fitted into the
corresponding tubular member 70.
[0066]
38
When the tubular member 70 is fitted to the pair of
first insertion segments 12, the end of the tubular member
70 comes into abutment with the angular tube section 11. In
this state, each side surface of the cube constituted by the
side surfaces of the angular tube section 11, the planar
portion 21, and the flat plate portion 41is flush with the
corresponding side surface of the tubular member 70, thereby
achieving a favorable external appearance with no steps
there between. Furthermore, since there are no steps
between the joining members and the tubular members 70,
there is no possibility of unstable installation of the
constructed framework structure on an installation surface
or rattling thereof.
[0067]
Once each tubular member 70 is fitted to the pair of
first insertion segments 12, the wedge member 60 is inserted
into the slits75 provided near the end of the tubular member
70. The wedge retainers 15 provided at the pair of first
insertion segments 12 and the slits75 correspond with each
other to have the positional relationship described above.
Therefore, as shown in Fig. 8B, the tabular wedge member 60
is retained between the pair of wedge retainers 15 providing
a gap between the two inner protrusions 16. As mentioned
above, since the length of the wedge member 60 in the
longitudinal direction is equal to the length L of each edge
of the square outer shape of the tubular member 70, the
opposite longitudinal ends of the wedge member 60 are
respectively fitted in the slits 75, as shown in Fig. 8A.
39
Thus, when an external force acts on the tubular member 70
in which the first insertion segments 12 of the first
joining member 10A is fitted, a possibility of the first
insertion segments 12 becoming distorted or buckling is
prevented by the wedge member 60.
[0068]
Accordingly, the tubular member 70 with its axial
direction as the X direction can be connected to the first
joining member 10A. With regard to each of the remaining
pair of first insertion segments 13 and the remaining pair
of second insertion segments 22, the end of the
corresponding tubular member 70 is externally fitted thereto,
similarly to the above, and the wedge member 60 is inserted
into the slits 75 in the tubular member 70. Accordingly,
the tubular member 70 with its axial direction as the Y
direction and the tubular member 70 with its axial direction
as the Z direction are connected to the first joining member
10A. Specifically, by using one L-shaped first joining
member 10Aand one second joining member 20, one tubular
member 70 with its axial direction as the X direction, one
tubular member 70 with its axial direction as the Y
direction, and one tubular member 70 with its axial
direction as the Z direction can be connected to one another,
whereby the corner area of the three-dimensional-frame-like
framework structure can be constructed.
[0069]
In the construction of the three-dimensional-frame-like
framework structure, for example, the T-shaped first joining
40
member10B, as shown in Fig. 10A and Fig. 10B, is used
together with the second joining member 20, so that one
tubular member 70 with its axial direction as the X
direction, two tubular members 70 with their axial direction
as the Y direction, and one tubular member 70 with its axial
direction as the Z direction can be connected to one another.
Furthermore, the cross-shaped first joining member 10C, as
shown in Fig. 11A and Fig. 11B, is used together with the
second joining member 20, so that two tubular members 70
with their axial direction as the X direction, two tubular
members 70 with their axial direction as the Y direction,
and one tubular member 70 with its axial direction as the Z
direction can be connected to one another.
[0070]
By combining each of the L-shaped first joining member
10A, the T-shaped first joining member 10B, and the cross-
shaped first joining member 10C with one second joining
member 20, an upper structure (see the upper part in Fig. 6)
and a lower structure (see the lower part in Fig. 6) of the
three-dimensional-frame-like framework structure can be
constructed.
[0071]
The structure of an area (see the middle part in Fig.
6) where two tubular members 70 with their axial direction
as the Z direction are connected from above and below in the
three-dimensional-frame-like framework structure will now be
described mainly with reference to Fig. 12A to Fig. 12C.
Fig. 12A to Fig. 12C illustrate the L-shaped first joining
41
member 10A' as an example. In this first joining member
10A', a pair of parallel side surfaces of the angular tube
section 11 are each provided with two securing slits 14 that
are separated from each other in the Z direction. The two
securing slits 14 are symmetrically provided with respect to
the center of the angular tube section 11 in the Z direction
as the boundary. Other components in the first joining
member 10A' are the same as those of the first joining
member 10A, and the description about the connection of the
tubular members 70 in the X direction and the Y direction
will be omitted.
[0072]
The first joining member 10A' can allow second joining
members 20 to be respectively connected to opposite sides of
the angular tube section 11 in the Z direction. In detail,
the pair of linkage insertion segments 23 of one second
joining member 20 are inserted from above into the angular
tube section 11 of the first joining member 10A', and the
pair of linkage insertion segments 23 of another second
joining member 20 are inserted from below into the angular
tube section 11 of the first joining member 10A'. Because
the first extending portion 30 and the second extending
portion 31 of each second joining member 20have shapes
corresponding with each other, as described above, the
second extending portion 31 of the other second joining
member20 is inserted between the first extending portion 30
of the one second joining member 20 and the corresponding
inner surface of the angular tube section 11, and the lock
42
claw 32 provided at the distal end of the first extending
portion 30 of the one second joining member 20 is locked to
the second recess 34 in the other second joining member 20
(see Fig. 12C). With the lock claw 32 being locked to the
second recess 34, the two second joining members 20 are
prevented from pulling out of the angular tube section 11.
[0073]
When the respective pairs of linkage insertion segments
23 of the second joining members 20 are inserted from above
and below into the angular tube section 11, the securing
members 50 are inserted into the two securing slits 14
separated from each other in the vertical direction (Z
direction). Accordingly, in accordance with reasons similar
to the above, the two second joining members 20 are
connected to the first joining member 10A', and the
respective pairs of second insertion segments 22 extend
upward and downward from the angular tube section 11 (see
Fig. 12B). Subsequently, the respective ends of the tubular
members 70 are externally fitted to the pair of second
insertion segments 22 extending upward from the angular tube
section 11 and the pair of second insertion segments 22
extending downward there from, and the wedge members 60 are
then inserted into the slits 75 near the respective ends of
the tubular members 70. Accordingly, the two tubular
members 70 with their axial direction as the Z direction can
be connected to the first joining member 10A'.
[0074]
Each T-shaped first joining member 10B and each cross-
43
shaped first joining member 10C can be turned into a first
joining member 10B' and a first joining member 10C',
respectively, by being provided with securing slits 14 in
areas indicated by dashed lines in Fig. 10B and Fig. 11B.
Accordingly, two tubular members 70 with their axial
direction as the Z direction can be connected to each of the
first joining member 10B' and the first joining member 10C'.
[0075]
With regard to the joining members for joining multiple
tubular members 70 to each other, the type of first joining
member used corresponds with the directions and the number
of tubular members 70 to be connected, so that the three-
dimensional-frame-like framework structure, as shown in Fig.
6, can be constructed.
[0076]
With regard to the joining members according to this
embodiment, a two-dimensional-frame-like framework structure
parallel to the XY plane can also be constructed by joining
tubular members 70 to the first joining member alone without
joining second joining members 20 to the first joining
member. In this case, two third joining members 40 are
connected to the first joining member.
[0077]
In detail, as shown in Fig. 13A to Fig. 13(c), with
regard to the first joining member 10A in which the axial
direction of the angular tube section 11 is aligned with the
vertical direction, the first retaining segment 42 and the
second retaining segment 43 of a third joining member 40 is
44
inserted from above into the angular tube section 11, and
the first retaining segment 42 and the second retaining
segment 43 of another third joining member 40 is inserted
from below into the angular tube section 11, thereby
bringing the respective planar portions 41 into abutment
with the angular tube section 11. Accordingly, the four
side surfaces of the angular tube section 11, the flat plate
portion 41 of the upper third joining member 40, and the
flat plate portion 41 of the lower third joining member
40constitute a cube with each edge having the length L (see
Fig. 13B). By joining the tubular members 70 to the first
joining member 10A in this state, the side surfaces of the
aforementioned cube become flush with the corresponding side
surfaces of the tubular members 70, thereby achieving a
favorable external appearance with no steps there between.
Furthermore, since there are no steps between the joining
members and the tubular members 70, there is no possibility
of unstable installation of the constructed framework
structure on an installation surface or rattling thereof.
[0078]
Because the first retaining segment 42 and the second
retaining segment 43 of each third joining member 40 have
shapes corresponding with each other, as described above,
the first retaining segment 42 of one of the third joining
members 40 is inserted between the outer surface at the
distal side relative to the cranked area of the second
retaining segment 43 of the other third joining member 40
and the corresponding inner surface of the angular tube
45
section 11. Moreover, the first claw 44 at the distal end
of the first retaining segment 42 of the one third joining
member40 is locked to the second groove 47 in the other
third joining member 40, and the second claw 46 at the
distal end of the second retaining segment 43 of the one
third joining member 40 is locked to the first groove 45 in
the other third joining member 40 (see Fig. 13(c)). With
the engagement between the first claw 44 and the second
groove 47 and the engagement between the second claw 46 and
the first groove 45, the two third joining members 40 are
prevented from pulling out of the angular tube section 11.
[0079]
The openings of the securing slits 14 in each first
joining member may be filled in by inserting the securing
members 50 into the securing slits 14.
[0080]
With the types of first joining members used
corresponding with the directions and the number of tubular
members 70 to be connected, various two-dimensional-frame-
like framework structures can be constructed.
[0081]
The two-dimensional-frame-like or three-dimensional-
frame-like framework structure constructed in this manner
can be used for various application purposes, such as a
framework for a pedestal, a temporary building, or a
greenhouse, a frame for a signboard or a signpost, and a
trolley. Although the application purposes are not
particularly limited, suitable applications include those
46
that require high mechanical strength or high stability with
no distortion and no rattling.
[0082]
Accordingly, in this embodiment, when the second
joining member 20 is connected to the first joining member
and the securing member 50 is inserted into the securing
slit 14, the securing member 50 is retained by the securing
member retainer28, so that relative movement of the second
joining member 20 in the axial direction of the angular tube
section 11 is prevented. Accordingly, as compared with the
related art, the connection strength between the first
joining member and the second joining member 20 can be
enhanced, and the connection strength between a tubular
member 70 with its axial direction as the X direction or the
Y direction and a tubular member 70 with its axial direction
as the Z direction can be enhanced. Consequently, a
framework structure with enhanced connection strength
between the tubular members 70 can be provided.
[0083]
In a created sample, the length L of each edge of the
square outer shape of the tubular member 70 is set to 40 mm,
the wall thickness d of the tubular member 70 is set to 2 mm,
the joining members and the tubular member70 are composed of
an aluminum alloy for wrought products, and the tubular
member 70 is connected to the first joining member with the
second joining member 20 interposed there between. In a
state where the angular tube section 11 of the sample is
fixed, a cantilever-bending test is performed. The
47
cantilever-bending test involves applying a load in the X
direction or the Y direction onto a point of the tubular
member 70 extending in the Z direction from the angular tube
section 11 to a predetermined position (in this case, 80 mm).
As a result, a maximum load until buckling occurs is 3872 N
in the X direction and 4607 N in the Y direction, whereby it
is confirmed that sufficient connection strength is obtained.
[0084]
With the insertion of the pair of second insertion
segments 22, the first joining member and the second joining
member 20 can be connected to have high connection strength,
so that a process for welding them together can be made
unnecessary. Because the welding process is not necessary,
as mentioned above, a framework structure can be constructed
even in an environment where it is difficult to perform the
welding process. Although it is not necessary to perform
welding for constructing the framework structure according
to this embodiment, this does not imply that welding is to
be excluded.
[0085]
Furthermore, in this embodiment, all of the members,
such as the first joining members (L-shaped first joining
members 10A, T-shaped first joining members 10B, and cross-
shaped first joining members 10C), the second joining
members 20, the third joining members 40, the securing
members 50, and the wedge members 60, used for joining
tubular members 70 to each other are manufactured by
extrusion molding, similarly to the tubular members 70.
48
Therefore, all of the components of the framework structure
can be composed of a metallic material having the same
composition. For example, all of the components of the
framework structure may be composed of an aluminum alloy for
wrought products. Accordingly, the problem in the related
art where distortion occurs in the framework structure due
to different thermal expansion coefficients among the
members can be resolved.
[0086]
When members are to be welded to each other, the
composition of the welded area becomes different from the
composition of the members, possibly causing distortion to
occur in the framework structure due to different thermal
expansion coefficients. As mentioned above, this embodiment
does not require a welding process, so that there is no
possibility of distortion occurring due to welding of the
framework structure.
[0087]
As mentioned above, all of the components of the
framework structure can be composed of a metallic material
having the same composition, so that a sorting process at
the time of disposal is not necessary, and a process for
reusing the materials is also simplified.
[0088]
In addition, in this embodiment, the framework
structure is constructed by the engagement between the
members, so that screws and bolts are not used whatsoever.
Thus, electrolytic corrosion is effectively prevented.
49
[0089]
Although the present invention has been described above
with reference to preferred embodiments, the present
invention is not limited to the above embodiments and
permits various modifications and design changes, as
indicated below, so long as they do not depart from the
scope of the invention.
[0090]
For example, in the above description, the orthogonal-
cross-sectional outer shape of each tubular member 70 is
square, and the outer shape of the angular tube section 11
of the first joining member as viewed from the Z direction
is also square with the same size. This is advantageous in
that the tubular members 70 of the same type can be used as
the tubular members 70 to be connected in the X direction,
the Y direction, and the Z direction without taking into
consideration the orientations thereof. However, if
different types of tubular members 70 are to be used
depending on the connection directions or if the
orientations in which the tubular members 70 are to be
connected are to be taken into consideration, the
orthogonal-cross-sectional outer shape of each tubular
member 70 and the outer shape of the angular tube section
11of the first joining member as viewed from the Z direction
may be rectangular. Even in such a case, the size and shape
can be set such that the side surfaces of the components of
the framework structure are flush with each other.
50
We Claim:
1. A joining member comprising a first joining member, a
second joining member, and a securing member,
wherein the first joining member comprises:
a rectangular-parallelepiped or cubical angular-pipe-
like angular tube section;
a pair of first insertion segments extending from each
of at least two side surfaces of four side surfaces parallel
to a Z direction as an axial direction of the angular tube
section, the pair of first insertion segments extending in
an X direction or a Y direction orthogonal to the Z
direction from positions located inward by a predetermined
distance relative to a pair of side edges, extending in the
Z direction, of each of the at least two side surfaces; and
a securing slit that passes in a thickness direction
through each of an opposing pair of the side surfaces of the
angular tube section and to which the securing member is
inserted,
wherein the second joining member comprises:
a square or rectangular planar portion;
a pair of second insertion segments extending
perpendicularly from the planar portion respectively along a
pair of side edges of one of surfaces of the planar portion;
a pair of linkage insertion segments extending
perpendicularly from the planar portion respectively along
the pair of side edges of a surface opposite the surface of
the planar portion from which the second insertion segments
51
extend, the pair of linkage insertion segments being
inserted in the angular tube section; and
a securing member retainer provided between the pair of
linkage insertion segments and for retaining the securing
member therein.
2. A framework structure constructed by joining tubular
members as angular pipes to each other by using a joining
member comprising a first joining member, a second joining
member, and a securing member,
wherein the first joining member comprises:
a rectangular-parallelepiped or cubical angular-pipe-
like angular tube section;
a pair of first insertion segments extending from each
of at least two side surfaces of four side surfaces parallel
to a Z direction as an axial direction of the angular tube
section, the pair of first insertion segments extending in
an X direction or a Y direction orthogonal to the Z
direction from positions located inward by a predetermined
distance relative to a pair of side edges, extending in the
Z direction, of each of the at least two side surfaces; and
a securing slit that passes in a thickness direction
through each of an opposing pair of the side surfaces of the
angular tube section and to which the securing member is
inserted,
wherein the second joining member comprises:
a square or rectangular planar portion;
a pair of second insertion segments extending
perpendicularly from the planar portion respectively along a
pair of side edges of one of surfaces of the planar portion;
a pair of linkage insertion segments extending
perpendicularly from the planar portion respectively along
the pair of side edges of a surface opposite the surface of
the planar portion from which the second insertion segments
extend, the pair of linkage insertion segirnents being
inserted in the angular tube section; and
a securing member retainer prov.j-ded between the pair of
linkage insertion segments and for retaining the securing
member therein,
wherein the second joining member is secured to the
first joining member as a result of the pair of linkage
insertion segments being inserted in the angular tube
section and the securing member inserted in the securing
slit being retained by the securing member retainer, and
wherein a plurality of the tubul-ar members are
connected to each other as a result of the paj-r of first
insertion segments and the pair of second insertion segments
being inserted into ends of the tubular members that are
di,fferent from each other.