JPH0416999Y2 - - Google Patents

Description

[Detailed explanation of the idea] (Industrial application field) The present invention relates to a mesh girder.

(Prior art) Conventional mesh girders are made by connecting a plurality of straight pipes a as shown in FIG.
It is composed of one tapered tubular beam member b. In the figure, c is a net.

In addition, when constructing a mesh girder by joining a plurality of straight pipes a, the adjacent pipe bodies may be glued together, or an overlay part d spanning the adjacent straight pipes a may be provided as shown in Fig. 5. d was glued to a straight tube a as shown by e.

In addition, in order to prevent the hollow tube or sleeve joint from breaking in the mesh girder where the hollow tube is fitted from both ends to the sleeve joint, the hollow tube or sleeve Japanese Utility Model Application Publication No. 17677/1987 proposes a mesh girder in which a rupture piece that breaks with an external force smaller than the breaking stress of the joint is removably fitted into a hollow pipe or sleeve joint.

(Problems to be solved by the invention) However, in the conventional mesh girder with which the straight pipe a is connected, force tends to concentrate near the pipe joint, and it bends with a crease, causing breakage. .

Furthermore, the work of gluing the straight pipe a on site requires a great deal of effort.

Furthermore, the tapered mesh girder has a large deflection at both ends, and there is a risk that the mesh girder's original role of widening the opening may be impaired.

In addition, in the conventional mesh girder using rupture pieces, a lot of effort is required each time the rupture piece is attached and removed, and the breaking stress differs depending on the joint position of the hollow pipe in the mesh girder. It is not easy to select the breaking strength of the rupture piece, but in order to make the rupture piece work effectively,
If the fracture strength is selected according to the joint position with the minimum stress, the rupture piece may be destroyed by stress that does not cause the sleeve joint or hollow tube to break.

(Means for solving the problem) The present invention was proposed to solve the above problem, and the thickness is gradually increased from both end pieces of the mesh girder to the center piece. It is composed of a plurality of tubular girder pieces each having one end formed as a mouse-shaped open end and the other end formed as a straight tube-like open end, each having a rope stopper on the outer periphery of both ends. Of a pair of adjacent tubular girder pieces, a piece is protruded from the outer periphery of the intermediate part, spanning the mouse-shaped opening end of one girder piece and the straight tubular opening end of the other girder piece. This relates to a mesh girder characterized in that the collar piece is fitted with a stop button, and is joined with a rope stopper protruding from the outer peripheral surface of each opening end of the two tubular pieces. be.

(Function) As described above, the mesh girder according to the present invention is constituted by a stepped mesh girder in which a plurality of tubular girder pieces are joined together, and the wall thickness gradually increases from both end pieces to the center piece. As a result, the force is dispersed and the deflection at both ends is reduced compared to the conventional tapered mesh girder.

In addition, among a pair of adjacent tubular girder pieces, the open end of one girder piece is shaped like a mouse, and the opening end of the mouse-shaped girder piece is straddled over the straight tubular open end of the other girder piece. , a stop bush having a protruding flange on the intermediate outer periphery is fitted to join the two tubular pieces together via the stop bush, and a rope stopper provided on the outer periphery of each end of the two tubular girder pieces is fitted. By joining, both the tubular girder pieces can be reliably joined without using an adhesive.

(Example) The present invention will be described below with reference to the illustrated embodiments.

A is an FRP type tubular girder piece that makes up the mesh girder.
One end is formed into a mouse-shaped open end 1, the other end is formed into a straight tube-shaped open end 2, and rope stoppers 3 are protruded from the outer periphery of both ends.

The wall thickness of the tubular girder pieces A gradually increases from both ends of the span of the mesh girder to the center thereof, and is joined via stop bushes B to form a stepped mesh girder.

Fig. 2 shows the joining part of the tubular girder parts, and shows the small diameter cylindrical part of the stop bush B made of FRP, which is formed by protruding a collar piece 4 on the outer periphery of the intermediate part of the small diameter cylindrical part and the large diameter cylindrical part. At the same time, the large-diameter cylinder part is fitted into the straight tube-shaped opening of the other tubular spar piece A, and both of the opposing tubular spar pieces The rope fixings 3 of the pieces A are tightened with bolts or ropes, thus joining the two tubular girder pieces A without the use of adhesives.

In the illustrated embodiment, as described above, the wall thickness of the tubular girder piece A constituting the mesh girder gradually increases from both ends of the span of the mesh girder to the middle part, so that the force applied to the mesh girder is In addition, the deflection at both ends is smaller than in the case of a tapered mesh girder, and a mesh girder with a wide opening is constructed. By connecting the rope stoppers 3 of each girder piece A with bolts and ropes, the girder pieces A can be easily joined together without using adhesive.

Note that 5 in the figure is a net.

(Effect of the invention) According to the invention, as described above, a stepped mesh girder is constructed by joining a plurality of tubular girder pieces whose wall thickness gradually increases from both ends of the mesh girder span to the center of the span. By doing this, the force applied to the mesh girder is dispersed,
Breakage of the rupture piece can be prevented without using the rupture piece as in the prior art, and the structure can be simplified. Furthermore, the deflection at both ends of the net girder is reduced compared to the conventional tapered net girder, so that the function of the net girder to widen the opening of the net is not impaired.

Further, according to the present invention, one end opening of the tubular spar piece is formed in a mouse shape, and the other end opening is formed in a straight pipe shape, so that the mouse-shaped opening end of the adjacent tubular spar part and the straight pipe shape are formed. By fitting a stop bushing having a flange protruding from the outer periphery of the intermediate portion across the open end, and connecting the rope stoppers provided on the outer periphery of the ends of both tubular girder pieces. , the two tubular girder pieces can be easily joined without using adhesive. At this time, the fitting position of the stop button into both the tubular girder pieces is determined by the flange piece on the outer periphery of the stop bush, and the joining operation of the tubular girder pieces by the stop bush is performed easily and reliably.

Further, by making the strength of the stop button slightly lower than the strength of the tubular girder piece, when excessive force is applied to the mesh girder, the stop button will break and repair becomes easy.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a part of the joint part of the tubular girder piece of an embodiment of the mesh girder according to the present invention;
The figure is a plan view showing how the mesh girder of the present invention is used.
4 and 4 are plan views showing the state of use of the conventional mesh girder, respectively, and FIG. 5 is a plan view showing a part of the joint section of the conventional mesh girder in a cross-sectional view. A... Tubular girder piece, B... Stop button,
1... Mouse-shaped open end, 2... Straight tube-shaped open end, 3... Rope stop, 4... Flange piece.

Claims (1)

[Scope of utility model registration request] The wall thickness gradually increases from both end pieces of the mesh girder to the center piece, and one end is formed into a mouse-shaped open end, and the other end is formed into a straight pipe-like open end. , and is composed of a plurality of tubular girder pieces each having a rope stopper on the outer periphery of both ends, of a pair of adjacent tubular girder pieces, the mouse-shaped open end of one girder piece and the other girder piece A stop bush having a flange protruding from the outer periphery of the intermediate portion is fitted over the straight tubular open ends, and a rope protrudes from the outer circumferential surface of each open end of both tubular pieces. A mesh girder characterized by being made by joining together stoppers.