JPH09100569A - Hub body for truss and joint construction of truss base using the hub body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the strength of a truss construction by strengthening joint construction of a built-up truss base. SOLUTION: A plurality of controlling members 21 are monolithically projected to the circumference of a hub 3A, and the controlling members 21 are provided in spaces around the joint ends 5 of neighboring frame members 2. When the controlling members 21 are provided to keep a split angle θ of the frame members 2 in a constant state, the frame members 2 are hard to bend in an in-plane direction even if axial load is applied to the frame members 2, strength and rigidity of a built-up truss base can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembly type space truss structure in which a frame member having an arbitrary cross-sectional shape such as a pipe and an extruded shape member is sequentially connected by a connecting member called a hub. The present invention relates to a hub body for constructing and a joint structure of a truss base using the hub body, and particularly strengthens a connecting portion between the frame member and the hub by restricting deformation of the frame member in the in-plane direction.

[0002]

2. Description of the Related Art Assembled space truss structures do not require bolts or welding for assembly, so assembly work is easy, high joint efficiency is obtained, and smart, high daylighting and wide pillar-free space are obtained. It is widely used for outdoor concert halls, gas stations, pools, roofs of exhibition halls, side walls of buildings, dome for botanical gardens, temple dome, etc. The truss-based joint methods for such truss structures are roughly classified into two methods: a ball joint method and a cylindrical joint method. 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 a joint structure of an assembling type space truss adopting the latter joint method. Here, the assembling type three-dimensional truss means a truss structure body in which the truss portion has a shape such as a dome type, a mosque type, a pyramid type, a flat structure type, or a barrel vault type, and these are independent structures. In some cases, as well as in some cases, it is a structure that is installed as a part of the structure. In the following description, the dome type is taken as a representative example, but it goes without saying that a truss structure corresponding to each type may be used.

FIGS. 6A and 6B are a plan view and a front view of a dome-shaped structure showing an example of a truss base in an assembled space truss structure adopting a cylindrical joint method.
FIG. 7 is an exploded perspective view showing a joint structure for forming a truss mark by a conventional method, and FIGS. 8A, 8B, and 8C are a front view, a plan view, and a side view of a frame member. In these drawings, reference numeral 1 denotes a truss base in a dome-shaped truss structure, which is composed of a large number of frame members 2 and a 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, and both ends thereof are crushed by press working or the like to form flat connecting end portions 5, and concavities and convexities 4 called dimples on both surfaces thereof.
Is provided. The hub 3 is usually an aluminum alloy (eg:
It is formed into a cylindrical body by an extruded die material made of (Al-Mg-Si alloy), a forged product, etc., and has a bolt insertion hole 6 in the center. In addition, the hub 3 is provided with 6 to 9 connecting grooves (slots) 8 which are radially formed on the outer peripheral surface and have irregularities 7 on the groove wall surface, and the connecting ends 5 of the frame member 2 are provided in the connecting grooves 8.
Are press-fitted from the axial direction to connect the frame members 2 to each other to form a truss mark. A bolt 9 is inserted into the bolt insertion hole 6, and a washer 10 and a holding plate 11 are fitted to the upper and lower projecting ends of the bolt 9 and the nut 1, respectively.
By pressing the holding plate 11 to the upper and lower surfaces of the hub 3 by fastening 2, the connecting end portion 5 is prevented 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 1 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. To be done.

In the truss base of such an assembling type space truss, since the flat connecting end portion 5 is provided at the end portion of the frame member 2, the number of parts of the connecting member can be reduced and In the case of constructing a structure having a three-dimensional curved surface structure, three angles (coin angle α, bent angle β, twist angle γ) are added to the joint portion in addition to the split angle θ between the connecting grooves 8 of the hub 3. 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.

[0005]

In the conventional truss-based joint structure of the above-mentioned conventional assembly type space truss,
Since the connecting end portion 5 of the frame member 2 is formed in a flat shape that is long in the axial direction (out-of-plane direction) of the hub 3, the hub 3
Although there is no particular problem in terms of strength with respect to the external force in the axial direction of the above, it is relatively weak in the in-plane direction of the hub 3 (circumferential direction of the hub), so that there is snow in a large truss structure,
When an axial compression or tensile load is applied non-uniformly to the frame member 2 due to an earthquake or the like, the root portion 5 of the frame member 2
There is a problem in that a may be deformed in the circumferential direction in the plane of the truss and the connection end portion 5 may be bent, resulting in partial damage or damage to the entire structure. In particular, in the case of a dome body as shown in FIG. 6, irregularly shaped portions other than triangles, in this figure, quadrangular portions appear in the circumferential direction of 1A and 1B in order to angle downward from the apex. .
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 disclosed in the above-mentioned Japanese Patent Laid-Open No. 7-102633. As described above, various measures are taken such as providing a reinforcing plate at the connection end. However, the use of thick-walled pipes increases the weight of the base structure itself, and shortening the frame members increases the frame members and truss points, which requires time for assembly work. 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 the deformation of the frame member in the circumferential direction with a relatively simple structure so as to achieve the truss structure. It is an object of the present invention to provide a truss hub body capable of increasing the strength of an object and a truss-based joint structure using the hub body.

[0008]

In order to achieve the above object, the present invention provides a truss grade hub in which a plurality of connecting grooves into which the connecting ends of a truss structure frame member are press-fitted are radially formed. In the above, a restriction portion for restricting deformation of a frame member adjacent to the outer circumference of the hub in the hub circumferential direction is extended. Further, in the present invention, the restricting portion has a fan shape, H
It is characterized in that it is formed by either one of a square shape and a square shape. Further, the present invention provides an assembly type space truss structure including a frame member having flat connecting ends at both ends and a hub having a plurality of connecting grooves radially formed to press fit the connecting ends. In a joint structure of a truss base to be constructed, a hub body integrally provided on the hub, the restriction portion being interposed in a space between adjacent connection ends of adjacent frame members and restricting deformation of the frame member in a hub circumferential direction. Is provided only in the weak point portion or in all the weak point portions.

In the present invention, the restricting portion interposed in the space between the connection end portions of the adjacent frame members holds the split angle θ of the frame members so that the frame members can apply a compressive or tensile load in the axial direction. When received, it regulates the circumferential deformation of the frame member. When the present hub body is used for the weak points of the truss structure and the other conventional hub body is used, the utilization of the existing material is increased and the cost increase can be suppressed to a low level. In addition, when the present hub body is used as a whole, the overall strength can be appropriately improved.

[0010]

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 a plan view showing a main part of a joint structure portion of a truss base in a prefabricated type space truss according to the present invention, and is drawn with a bolt and a holding plate omitted. FIG. 2 is a front view showing a joint structure of the truss base. 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 these figures, in the present embodiment, a plurality of restricting portions 21 are radially extended integrally on the outer periphery of the hub 3A, and these restricting portions 21 are provided between adjacent connecting end portions 5 of the frame members 2. Intervenes in the space. Since the restriction portions 21 are provided between the connection grooves 8 of the hub 3A, the restriction portions 21 have the same number as the connection grooves 8 and are formed in a hollow body having a fan shape in plan view and a constant wall thickness. The hub 3A integrally provided with such a hollow restricting portion 21 can be easily manufactured by extrusion molding of an aluminum alloy, for example.

Both end portions of the frame member 2 are crushed from both sides by press working or the like to form tapered taper portions 22, and a flat connecting end portion 5 is provided at the tip end thereof, and the connecting end portion is provided. 5 is press-fitted into the connecting groove 8 of the hub 3A. For this reason, the space between the adjacent connection ends 5 of the adjacent frame members 2 forms a fan-shaped space, and the restriction portion 21 is formed so as to have substantially the same shape as this space,
Both side surfaces thereof are in close contact with the side surfaces of the taper portion 22 of the adjacent frame member 2, respectively. The other structure is the same as the joint structure of the truss base in the conventional assembled space truss shown in FIGS. 6 to 8.

The shape of the restricting portion 21 in plan view is not limited to the fan shape, but may be various shapes as shown in FIGS. 3 and 4. In FIG. 3, the plate-shaped portion 31 extending on the outer peripheral surface of the hub 3B and the H-shaped space setting portion 32 integrally provided at the tip of the plate-shaped portion 31 constitute the restriction portion 21, and the space setting portion is formed. The frame member 2 which adjoins both side surfaces of 32
An example in which the side surfaces of the tapered portion 22 are closely contacted is shown.
FIG. 4 shows a plate-shaped portion 31 extending on the outer peripheral surface of the hub 3C and a square-shaped space setting portion 3 provided integrally with the tip of the plate-shaped portion 31.
4, the restriction portion 21 is constituted by 4 and the side surfaces of the interval setting portion 34 are brought into close contact with the side surfaces of the taper portions 22 of the adjacent frame members 2, respectively. 3 and 4, the bolt and the holding plate are omitted as in FIG.

In the joint structure of the truss base in the assembling space truss having such a structure, the restricting portion 2
Since the split angle θ between the adjacent frame members 2 can be kept constant by 1, the frame member 2 receives a rotational moment in the circumferential direction when the frame member 2 locally receives a compressive or tensile load in the axial direction. It is possible to increase the resistance force against the rotation of the frame member 2 in the in-plane direction (directions of arrows A and B in FIG. 1) without being generated. Therefore, the connecting end 5 of the frame member 2 does not bend in the in-plane direction, and the overall strength of the assembled space truss base can be increased. In addition, the restriction portion 21 is connected to the hubs 3A, 3B, 3
Since it is integrally provided in C, the number of parts does not increase, the manufacturing is simple and the assembling work is easy. The above-mentioned hub body is provided in the weak point part of the truss mark, and the truss base is constructed using the conventional hub in other parts, or the above-mentioned hub body is constructed in the truss mark of the figure part. The external appearance of the entire structure is similar to that shown in FIG.

FIG. 5 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 assembly type truss is configured by using such a spectacle-shaped frame member 2A, the thin straight tube 40 can be used and the length of the hub 3 becomes long, but the outer diameter of the hub 3 can be made small, and the high strength can be further improved. A formula truss base can be formed. In addition, although the case where the number of connecting grooves formed in the hub body is 6 and 8 has been illustrated, the number of the restricting portions 21 may be similarly increased in the case of 9. Further, the shape of the restriction portion is not limited to the illustrated one. For example, in the case of a fan-shaped restricting portion, only the outer periphery of the hollow may be thickened to have an uneven thickness or to have a solid shape. Similarly, the space setting portion of the square-shaped restriction portion can be changed from a hollow shape to a solid shape. Further, among the truss structures, in the case of the pyramid type, the flat structure type, the barrel vault type, etc., the two-layer structure is mainly used as the truss base structure.

[0015]

As described above, the truss hub body according to the present invention is for a truss grade in which a plurality of connecting grooves into which the connecting ends of the truss structure frame member are press-fitted are radially formed. In the hub, a restricting portion that restricts deformation of the frame member adjacent to the outer periphery of the hub in the hub circumferential direction is extended, and the restricting portion preferably has a fan shape or an H shape. Since it is formed in either a V shape or a square shape, the conventional frame member can be applied as it is, the deformation of the frame member can be appropriately prevented, and the number of parts can be increased. Since there is no such thing, site management can be the same as before.

Further, according to the present invention, a frame truss having flat connection ends at both ends thereof and a hub having a plurality of connecting grooves radially formed with a plurality of connecting grooves into which the connection ends are press-fitted are formed. In a joint structure of a truss base for constructing a structure, a restricting portion that intervenes in the space between the connection end portions of adjacent frame members and restricts deformation of the frame member in the hub circumferential direction is integrally extended to the hub. Since the hub body is placed only on the weak points or on all the weak points, the frame member can maintain a constant split angle even if it receives a load in the axial direction, and it is difficult to bend in the in-plane direction. Therefore, the rigidity can be increased, and it becomes possible to construct a large assembled space truss. Further, since the restricting portion is provided integrally with the hub, the number of parts does not increase, the structure is simple, and the assembling work is easy.

[Brief description of the drawings]

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

FIG. 2 is a front view of a joint structure portion of the truss base.

FIG. 3 is a plan view showing another embodiment of the present invention.

FIG. 4 is a plan view showing still another embodiment of the present invention.

FIG. 5 is a partially cutaway front view showing another embodiment of the frame member.

6A and 6B are a plan view and a front view of a dome type truss base structure showing an example of an assembled truss structure.

FIG. 7 is an exploded perspective view showing a conventional joint structure forming a truss mark.

8A, 8B, and 8C are a front view, a plan view, and a side view of a frame member.

[Explanation of symbols]

1 ... Dome type truss base structure, 2, 2A, 2B, 2C
... frame member, 3, 3A, 3B, 3C ... hub, 5 ... connecting end, 8 ... connecting groove, 9 ... bolt, 11 ... holding plate, 21
… Regulator, 22… Taper.

Claims (3)

[Claims] 1. In a hub for truss rating, in which a plurality of connecting grooves into which the connection ends of the truss structure frame member are press-fitted are radially formed, a hub circumferential direction of the frame member adjacent to the outer periphery of the hub. A hub body for a truss, which is characterized in that a restriction portion for restricting the deformation of the truss is extended. 2. The truss hub body according to claim 1, wherein the restricting portion is formed in any one of a fan shape, an H shape, and a B shape. 3. An assembled space truss structure is constructed by a frame member having flat connecting ends at both ends thereof and a hub having a plurality of connecting grooves radially formed therein into which the connecting ends are press fitted. In the joint structure of the truss base, a hub body integrally extending to the hub is provided in the space between the connection end portions of the adjacent frame members, the restriction portion for restricting deformation of the frame member in the hub circumferential direction. A truss-based joint structure characterized by being placed only on the weak points or on all points.