JPH09242186A - Fabrication truss base structural body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the strength of a truss structure by strengthen the joint parts of a structure. SOLUTION: The hub 3 is constituted of two divided hubs 3A being divided at substantially central part in its axial direction. A rotation regulation member 21 formed into a disk is interposed between the two divided hubs 3A. The rotational regulation member 21 has a plurality of fitting grooves 22 being larger in its outer diameter than that of the divided hubs 3A and press-inserted with the joint end part 5 of a frame member 2. Each free end side of the fitting grooves 22 is formed taperingly to be spread toward the outside, so that it is brought in close contact with the tapered part 23 of the frame member 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembly type three-dimensional truss in which a frame-shaped member having a desired cross-section such as a pipe or an extruded member is sequentially connected by a cylindrical connecting member called a hub. The present invention relates to a prefabricated truss base structure for constructing a structure, and in particular, strengthens a connecting portion between a frame member and a cylindrical hub by restricting deformation of the frame member in the circumferential direction of the hub.

[0002]

2. Description of the Related Art An assembled space truss structure is a truss base structure constructed by connecting end portions of a frame member made of a pipe or the like by a cylindrical connecting member called a hub, and a glass plate is formed on the outer surface of the truss base structure according to the use. , A panel, a plate member, or the like is attached (eg, Japanese Patent Laid-Open No. 3-247831).
Gazette, Jitsukaihei 2-98121 gazette, etc.). Such a truss structure does not require joining by bolts or welding during assembly, so assembly work is easy, high joint efficiency is obtained, and smart, high daylighting and a wide pillar-free space are obtained. Because of its excellent characteristics, it is widely used in outdoor concert halls, gas stations, pools, roofs of exhibition halls, side walls of buildings, dome for botanical gardens, temple dome, etc.

There are roughly two types of truss-based joint systems for truss structures: a ball joint system and a cylindrical joint system. In the former, a spherical joint (hub) is used for the truss mark, and the frame members are sequentially connected by this (Japanese Patent Laid-Open No. 7-11705).
The latter uses a cylindrical joint (hub) and a frame member having a connecting end formed by crushing (US Pat. No. 2,931,467, Japanese Utility Model Laid-Open No. 2-98121, Japanese Patent No. The present invention relates to an assembly type truss base structure adopting the latter joint method.

Here, the assembled truss base structure means that the truss portion is a dome type, a mosque type, a pyramid type,
It refers to a truss structure having a flat structure type, a barrel vault type, or the like, and may be an independent structure, or may be a structure attached as a part of the structure. Further, in the following description, a dome shape is taken as a typical example, but it goes without saying that it may be applied to a truss structure corresponding to another shape.

FIGS. 4A and 4B are a plan view and a front view showing an example of a truss base structure in a dome type assembled space truss structure adopting a cylindrical joint method, and FIG. 6A, 6B, and 6C are an exploded perspective view showing a joining structure for forming dots, and FIGS. 6A, 6B, and 6C are a front view, a plan view, and a side view, respectively. In these drawings, reference numeral 1 denotes a truss base structure in a dome-shaped truss structure, which is composed of a large number of frame members 2 and a cylindrical hub 3 connecting these frame members 2.

The frame member 2 is usually made of a straight pipe made of aluminum alloy or the like. Both ends of the frame member 2 are crushed by press working or the like to form flat connecting end portions 5, and concavities and convexities 4 called dimples are provided on both surfaces thereof. There is.

The cylindrical hub 3 is usually formed into a cylindrical body by extruding an aluminum alloy (eg, Al--Mg--Si alloy), forging, etc., and has a bolt insertion hole 6 in the center. In addition, the hub 3 is radially formed on the outer peripheral surface according to the truss structure body in which the hub 3 is used, and the groove wall surface has unevenness 7.
6 to 9 connecting grooves (slots) 8 each having the frame member 2 are connected to each other by press-fitting the connecting end portion 5 of the frame member 2 into the connecting groove 8 from the axial direction to form a truss case. Forming a point. For example, the dome shape,
Truss-based structure such as mosque type (hereinafter referred to as "dome type")
(Also referred to as), a cylindrical hub having six connecting grooves 8 is used. A bolt 9 is inserted through the bolt insertion hole 6, a washer 10 and a holding plate 11 are fitted to the upper and lower projecting ends of the bolt 9, and a nut 12 is tightened to hold the holding plate 11 in place.
Is pressed against the upper and lower surfaces of the hub 3 to prevent the connecting end portion 5 from coming off the connecting groove 8. The bolt 9 and the holding plate 11 are also used for mounting the roof panel member on the hub 3. Then, the truss base structure 1 of the assembly type three-dimensional truss structure is constructed by connecting the truss points with the frame member 2, and the roof member is placed on the truss base structure 1 to complete the dome type truss structure and the like. To be done.

In the truss base structure 1 of such an assembled truss, since the connecting end portion 5 formed by flatly crushing is provided at the end portion of the frame member 2, the number of parts of the connecting member is reduced. In addition to reducing the number, when constructing a structure having a three-dimensional curved surface structure, the connecting groove 8 of the hub 3
By making three angles (coin angle α, bent angle β, twist angle γ) on the joint in addition to the split angle θ, the sphericity of the frame member itself can be obtained. Further, the truss base structure can be simplified because the truss base structure can have a high yield strength against a load in the axial direction (out-of-plane direction) of the hub 3 and can be a single truss. The coin angle α is the cutting angle of the connecting end 5, the bent angle β is the angle formed by the axis of the frame member 2 and the connecting end 5, and the twist angle γ is the height of the adjacent sides of the frame member and the hub. It is the angle formed between the connection ends of the frame members that connect the connection grooves between the hubs having different axial centers of curvature.

[0009]

In the joint structure of the truss base structure in the above-mentioned conventional assembly type truss, the connecting end portion 5 of the frame member 2 has a flat shape long in the axial direction (out-of-plane direction) of the hub 3. Because it is formed,
There is no particular problem in terms of strength with respect to the external force in the axial direction of the hub 3. However, it is relatively weak in the in-plane direction of the hub 3 (circumferential direction of the hub), and therefore, in a large dome type truss structure, the frame member 2 is compressed or pulled in the axial direction due to snowfall, an earthquake, or the like. When the load is applied non-uniformly, the root portion 5a of the connection end portion 5 may be deformed and bent in the circumferential direction in the truss plane, and may be partially destroyed or the entire structure may be destroyed. Was a dome with a diameter of 50 m. In particular, in the case of a dome body as shown in FIG. 4, irregular portions other than triangles appear in a plurality of positions for angling downward from the apex, in this figure, quadrangular portions appear in the circumferential direction of 1A and 1B. . Since such a portion has a different balance from the other portions, it tends to be a weak point portion in the truss structure. It is effective to reinforce this part preferentially, and it is more desirable to reinforce all truss grades if cost permits.

Therefore, in order to construct a large structure, a frame member made of a thick pipe is used, the length of the frame member is shortened, or the above-mentioned Japanese Patent Laid-Open No. 7-102633 is disclosed. As described above, various measures are taken such as providing a reinforcing plate on the connection end portion 5.

However, if a thick pipe is used,
If the weight of the truss base structure itself is increased and the frame member is shortened, the frame member and the truss grade are increased, so that the assembly work takes time. Further, when the reinforcing plate is used, not only the number of parts increases and the manufacturing of the connection end portion 5 is troublesome, but also the thickness of the connection end portion 5 increases, so that the groove width of the connecting groove 8 increases and the hub 3 of the hub 3 increases. There was a problem that the diameter also increased proportionally and the weight of the hub also increased.

The present invention has been made in order to solve the above-mentioned conventional problems, and an object thereof is to restrict deformation of a frame member in the circumferential direction of a hub with a relatively simple structure. Accordingly, it is an object of the present invention to provide an assembled truss base structure capable of increasing the strength of the truss structure.

[0013]

In order to achieve the above object, the present invention provides a frame member whose both ends form flat connecting ends, and a plurality of frame members into which the connecting ends are press-fitted. In an assembled truss base structure for constructing an assembled space truss structure with a cylindrical hub in which connecting grooves are formed in a radial pattern, at least the cylindrical hub in the axial direction of the cylindrical hub belongs to a weak point part. It is composed of two divided hubs divided at the center, and has a disc-like shape having a larger outer diameter than the divided hub and radially formed with a plurality of fitting grooves into which the connecting ends of the frame members are press-fitted. A rotation restricting member is interposed between the two divided hubs. Further, the present invention is characterized in that the rotation restricting member is formed by cutting the extruded material into slices. Further, the present invention is characterized in that the rotation regulating member is formed by laser cutting a plate material. Further, the present invention, the rotation regulating member is manufactured by die casting,
The rotation restricting member is characterized in that the outer peripheral portion of the frame member is thicker than the inner peripheral portion of the connecting end portion of the frame member.

In the present invention, the rotation restricting member interposed between the split hubs has an outer diameter larger than that of the cylindrical hub.
Since the frame member abuts on the side closer to the center than the connecting end, the frame member is prevented from being deformed in the circumferential direction of the hub when the frame member receives a compressive or tensile load in the axial direction. The rotation regulating member formed by cutting the aluminum extruded material into slices can be manufactured at low cost when a large amount is used. The rotation restriction member formed by laser cutting the plate material does not require the production of an extrusion die when producing in small quantities,
It is advantageous in cost. The rotation restricting member having the outer peripheral portion formed thicker than the inner peripheral portion has a higher strength in the direction around the axis of the hub, as compared with the case where the thickness is not formed. In addition, die casting can be manufactured at a lower cost than cutting.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail based on the embodiments shown in the drawings. FIG. 1 is an exploded perspective view showing main components of a joint structure portion of a truss base structure in a prefabricated truss according to the present invention, and is drawn with a bolt and a holding plate omitted. In addition, the same components as those described in the section of the prior art are denoted by the same reference numerals, and the description thereof will be omitted. In the present embodiment, at least two divided hubs 3A, which are obtained by vertically dividing the cylindrical hub 3 at the position belonging to the weak point portion at substantially the center in the axial direction,
3A, the rotation restricting member 21 is interposed between the divided hubs 3A, 3A, and these are integrally connected by the bolt 9 and the nut 12 via the pair of holding plates 11 shown in FIG.

Each split hub 3A is manufactured by extrusion molding of an aluminum alloy, and the frame member 2 is formed on the outer periphery thereof.
A plurality of connecting grooves 8 into which the connecting end portions 5 are press-fitted are radially formed. In addition, unevenness 7 is formed on the groove wall surface of the connecting groove 8 over the entire length, and the connecting end portion 5 of the frame member 2 is press-fitted into the connecting groove 8 from the axial direction to connect the frame members 2 to each other. It forms the truss mark.

The rotation restricting member 21 is formed in a disk shape having an appropriate plate thickness and has an outer diameter larger than the outer diameter of the split hub 3A, and the connecting end portion 5 of the frame member 2 is press-fitted into the outer circumference. A plurality of fitting grooves 21 are radially formed. Concavities and convexities 22 are formed on the wall surface of the inner side groove of the fitting groove 21 so as to correspond to the concavities and convexities 7 of the divided hub 3A, and the open portion is formed in a tapered shape that widens outward.

The rotation restricting member 20 as described above can be manufactured by various manufacturing methods, but in the case of mass production, it is manufactured by cutting an aluminum extruded material into slices. Also,
At the time of small-scale production, a plate made of aluminum alloy or the like is manufactured by laser cutting or die casting.

Both ends of the frame member 2 are crushed from both sides by press working or the like to form a tapered taper portion 23, and a flat connecting end portion 5 is provided at the tip thereof.
Is provided, and the connecting end portion 5 is press-fitted into the connecting groove 8 of each split hub 3A and the fitting groove 22 of the rotation restricting member 21. On both sides of the connection end portion 5, unevenness 4 that fits into the unevenness 7 and 22 of the split hub 3A and the rotation restricting member 21 is formed over the entire length. Connect the connection end 5 to the fitting groove 22
When press-fitted into, the wall surface of the open side groove of the fitting groove 22 comes into close contact with both side surfaces of the tapered portion 23 of the frame member 2 because the outer diameter of the rotation restricting member 21 is larger than that of the split hub 3A as described above. The other structure is the same as the joint structure of the truss base structure in the conventional assembly type truss shown in FIGS.

In the joining structure of the truss base structure in the assembled truss having such a structure, the rotation restricting member 21 having an outer diameter larger than these is interposed between the two divided hubs 3A, and the fitting groove thereof. Since the wall surface of the open side groove of 22 is brought into close contact with both side surfaces of the taper portion 23 of the frame member 2, the rotation restricting member 21 serves as a support for the frame member 2 and makes the split angle θ of the adjacent frame members 2 constant. Hold. Therefore, when the frame member 2 locally receives a compressive or tensile load in the axial direction, a rotational moment that rotates the frame member 2 in the circumferential direction of the hub does not occur, and the in-plane direction of the frame member 2 (see FIG. Arrows A and B of 1
It is possible to increase the resistance to the rotation of the (direction). Therefore, the connecting end 5 of the frame member 2 is not bent in the circumferential direction of the hub, and the overall strength of the truss base structure can be increased.

Further, the split hub 3A need only be formed to have a length of 1/2 of the length of the connection end 5 minus the plate thickness of the rotation restricting member 20, so the design can be changed. Available without. Further, the rotation regulating member 21 formed by cutting the aluminum extruded material into slices can be manufactured at low cost when used in a large amount. On the other hand, when a small amount is produced, the plate material is formed by laser cutting, so that it is not necessary to manufacture an extrusion die for manufacturing an aluminum extruded material, which is advantageous in terms of cost.

FIG. 2 is an exploded perspective view showing another embodiment of the present invention. In this embodiment, the rotation restricting member 21 is manufactured by die casting, and the outer peripheral portion 2 of the rotation restricting member 21 from the connecting end 5 of the frame member 2 is manufactured.
1a is formed thicker than the inner peripheral portion 21b. Further, a concave portion 25 into which the upper and lower split hubs 3A are fitted is formed in the center of the upper and lower surfaces of the rotation restricting member 21. Further, if desired, the recesses 26 may be formed on the upper and lower surfaces of the thick outer peripheral portion 21a to reduce the weight.

In such a rotation restricting member 21,
Outer peripheral portion 21a that abuts the tapered portion 23 of the frame member 2
Since the wall thickness is larger than that in the above-described embodiment, it is possible to further increase the resistance against the rotation of the frame member 2 in the in-plane direction. As a result, the frame member 2
The connecting end portion 5 of FIG. 3 does not bend in the in-plane direction of the dome, and the overall strength of the truss base structure can be increased. Further, if the rotation regulating member 21 is manufactured by die casting, it is cheaper than that manufactured by cutting. In addition, in the present embodiment, the recess 25 is formed on the upper surface side of the rotation restricting member 21, but the recess may be formed on the lower surface side or both upper and lower surfaces.

FIG. 3 is a partially cutaway front view showing another embodiment of the frame member. In this embodiment, a frame having a spectacle-like cross section is formed by two straight pipes 40 integrally provided with flat connecting ends 5 at both ends and a connecting plate 41 connecting the straight pipes 40. It constitutes the member 2A. Such a frame member 2A
Cuts an extruded shape member composed of two straight pipes 40 and a connecting plate 41 into a predetermined size to crush the end portions of each straight pipe 40 into a flat shape, and cuts both end portions of the connecting plate 41 into a concave shape. It can be easily manufactured by removing.

When the spectacle-shaped frame member 2A is connected to the hub 3 shown in FIG. 1 or 2 by the rotation restricting member 21 to form a truss-grade assembled truss, a thin straight pipe 40 is used. Although the length of the hub 3 is increased, the outer diameter of the hub 3 can be reduced, and a high-strength single-layer truss base structure can be formed.

In each of the above-described embodiments, the case where the number of connecting grooves formed in the hub 3 is 6 has been illustrated, but the number is not limited to this, and the number can be increased or decreased as appropriate. For example, the flat structure type and barrel vault type have 8 connecting grooves, and the pyramid side has 9 connecting grooves.
A hub is used which is provided with each of the connecting grooves. Further, although the present invention is suitable for a dome type and a mosque type, it can be applied to any of a pyramid type, a flat structure type, and a barrel vault type according to design requirements.

[0027]

As described above, in the assembled truss base structure according to the present invention, the frame member whose both ends form a flat connecting end, and the connecting end of the frame member are press-fitted. In a prefabricated truss base structure for constructing a prefabricated space truss structure with a cylindrical hub in which a plurality of connecting grooves are formed radially, at least the cylindrical hub belonging to the weak point part has the axis of the cylindrical hub. A circle having a plurality of split hubs that are split at approximately the center of the direction and have a larger outer diameter than the split hub, and a plurality of fitting grooves into which the connecting end of the frame member is press-fitted are radially formed. Since the plate-shaped rotation restricting member is interposed between the two divided hubs, the hub itself can be manufactured by changing its length.
The shape does not need to be changed, the conventional frame member can be applied as it is, and the rotation restricting member serves as a support for the frame member with respect to the frame member and maintains a constant split angle between the adjacent frame members. Therefore, when the frame member locally receives a compressive or tensile load in the axial direction, a rotational moment in the circumferential direction of the hub is not generated in the frame member, and the resistance force against the in-plane rotation of the frame member is increased. You can Therefore, when applied to the hub of the truss grade part connected to the square part that is the weak point part of the dome type truss base structure, the connecting end of the frame member does not bend in the circumferential direction of the hub and the truss base structure It is possible to increase the overall strength of the body, and it is possible to construct a larger-scale truss base structure, for example, a frame member having an abnormal diameter of 100 m, which has been conventionally used. Even in the same scale truss base structure as before,
It becomes possible to use a frame member having a small diameter or a thin wall while maintaining the same strength. Further, according to the present invention, since the outer peripheral portion is formed thicker than the inner peripheral portion from the connecting end portion of the frame member of the rotation restricting member, the strength and rigidity of the assembled truss structure can be further increased, and the large-sized It is possible to construct an assembled truss structure.

Further, in the present invention, since the rotation restricting member is formed by cutting the extruded material into slices, the truss base structure can be manufactured at a low cost when used in a large amount. Also,
In the present invention, since the rotation restricting member is formed by laser cutting the plate material, it is not necessary to manufacture an extrusion die when producing a small amount, which is advantageous in terms of cost. Further, in the present invention, since the rotation restricting member is formed by die casting, it can be manufactured at a lower cost than cutting work. Furthermore, if applied to a flat structure type or barrel vault type in which the weak points of the square portion do not appear, the safety factor in terms of strength can be increased.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a main part of a joint structure portion of a truss base structure in an assembled truss according to the present invention.

FIG. 2 is an exploded perspective view of a joining structure portion showing another embodiment of the present invention.

FIG. 3 is a partially cutaway front view showing another embodiment of the frame member.

4A and 4B are a plan view and a front view of a dome-shaped truss base structure showing an example of an assembled truss structure.

FIG. 5 is an exploded perspective view showing a conventional joint structure forming a truss mark.

6 (A), (B) and (C) are a front view, a plan view and a side view of a frame member.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Dome type truss base structure, 2, 2A ... Frame member, 3, 3A ... Hub, 5 ... Connection end part, 8 ... Connection groove, 9
... bolts, 11 ... holding plates, 21 ... rotation restricting members, 22 ...
Fitting groove, 23 ... Tapered portion, 25 ... Recessed portion, 26 ... Recessed portion.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomoshige Kawamura 1-34-1 Kambara, Kambara-cho, Anbara-gun, Shizuoka Prefecture, Japan Group Technology Center, Nippon Light Metal Co., Ltd. (72) Kiyofumi Tanaka Kambara-cho, Anbara-gun, Shizuoka Prefecture 1-34-1, Nippon Light Metal Co., Ltd. Group Technology Center

Claims (4)

[Claims] 1. A frame member having flat connecting ends at both ends, and a cylindrical hub having a plurality of connecting grooves radially formed therein into which the connecting ends of the frame member are press-fitted. In an assembled truss base structure for constructing an assembled space truss structure, at least a cylindrical hub belonging to a weak point portion constitutes the cylindrical hub with two divided hubs which are divided at substantially the center in the axial direction, and this division is performed. A disc-shaped rotation restricting member having an outer diameter larger than that of the hub and radially formed with a plurality of fitting grooves into which the connecting ends of the frame members are press-fitted is interposed between the two divided hubs. A prefabricated truss base structure characterized in that 2. The assembled truss base structure according to claim 1, wherein the rotation restricting member is formed by cutting an extruded material into slices. 3. The assembly-type truss base structure according to claim 1, wherein the rotation restricting member is formed by laser cutting a plate material. 4. The assembly-type truss base structure according to claim 1, wherein the rotation restricting member is manufactured by die casting, and the outer peripheral portion of the frame member of the rotation restricting member is thicker at the outer peripheral portion than at the inner peripheral portion. An assembling truss base structure characterized in that