JP2016079766A - Tornado protection net - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tornado protection net capable of preferably protecting an object from a flying object flown by a tornado.SOLUTION: The tornado protection net includes: a protection net main part 4; and a border rope attached to the protection net main part 4. The protection net main part 4 includes: a first net 5; a second net 6 having a mesh different from that of the first net; and a third net 7 which has a mesh larger than the opening area of the mesh of at least the second net. The first net 5, the second net 6 and the third net 7 are overlapped with each other.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a tornado protection net.

Nets that catch and protect rocks and landslides are widely known. In order to prevent damage to the net due to the impact of falling rocks or the like, a technology capable of efficiently absorbing energy such as falling rocks has been proposed.
For example, Patent Document 1 discloses that a reinforcing net that reinforces a protective net is provided in an area where a flying object is highly likely to collide, in addition to a protective net that protects the flying object.

JP2013-256845A

However, in the invention described in Patent Document 1, the reinforcement net is arranged on at least one of the front and back sides of the protection net, so that the strength of the part where the reinforcement net is arranged is only increased, and a large flying object If a small projectile hits various parts of the net, sufficient protection may not be possible.
The flying objects flying by the tornado are various objects wound up by the tornado, and have various sizes, shapes, and weights. The invention described in Patent Document 1 is not sufficiently considered for flying objects flying by a tornado.

  This invention is made | formed in view of the situation mentioned above, The objective is to provide the net | network for tornado protection which can protect suitably the flying object which flies by a tornado.

  One aspect of the present invention includes a protective net body and a border rope attached to the protective net body. The protective net body includes a first net and a first net different from the first net. 2 and a third net having a mesh size at least larger than the opening area of the second net, the first net, the second net, and the third net This is a tornado protection net that is superimposed on the net.

  The tornado protection net of the above aspect can receive the flying object by the first net, the second net, and the third net, respectively, corresponding to the size of the flying object. In the above aspect, the meshes having at least two types of mesh sizes are overlapped, and a larger mesh can receive a large flying object, and a smaller mesh can receive a smaller flying object.

The third network may have the same network as the second network.
In this case, since the third net and the second net are overlapped, the durability is high.

The first network may be arranged between the third network and the second network.
In this case, since a relatively small mesh and a relatively large mesh are alternately stacked, the relatively small mesh on the side where the flying object collides is relatively Since it is held by a large mesh, it is difficult to bend.

The second net and the third net may have anisotropy in strength in a planar direction. At this time, the second net and the third net are different from each other. It is superimposed to cancel the direction.
In this case, the second net and the third net are overlapped to form a structure having no anisotropy in strength in the plane direction as a whole.

The second network may have a smaller network than the first network.
In this case, the second net can catch a small flying object passing through the first net.

The second network may have a mesh larger than that of the first network.
In this case, the second net can receive the flying object received by the first net together with the first net.

  ADVANTAGE OF THE INVENTION According to this invention, the tornado protection net which can protect suitably the flying object which flies by a tornado can be provided.

It is a perspective view of the tornado protection net of a 1st embodiment of the present invention. It is sectional drawing which shows the protection net body in the tornado protection net. It is a figure for demonstrating the effect | action of a protection net main body. It is a figure for demonstrating the effect | action of a protection net main body. It is sectional drawing which shows the protection net body in the tornado protection net of 2nd Embodiment of this invention. It is a figure for demonstrating the effect | action of a protection net main body. It is a figure for demonstrating the effect | action of a protection net main body.

(First embodiment)
A first embodiment of the present invention will be described. FIG. 1 is a perspective view of a tornado protection net of the present embodiment. FIG. 2 is a cross-sectional view showing a protective net body in the tornado protective net. 3 and 4 are views for explaining the operation of the protective net body.
A tornado protection net 1 according to this embodiment shown in FIG. 1 includes a border rope 2, a fixed end member 3, and a protection net body 4.

  The border rope 2 is a wire rope attached to the protective net body 4 via a connector. A total of four border ropes 2 are provided for each side of the outer periphery of the protective net body 4. The border rope 2 is stretched in a straight line along each side of the protective net body 4 to apply tension to the protective net body 4 for spreading the protective net body 4. Further, the border rope 2 receives traction force from the protective net body 4 when the flying net collides with the protective net body 4 in a state where the protective net body 4 is stretched and spread, and the protective net body 4 bends.

  The fixed end member 3 is a member that can be fixed to the installation target and can be connected to the border rope 2 in order to fix the fixed end 2 a of the border rope 2 to the installation target. The configuration of the fixed end member 3 is not particularly limited, but the fixed end member 3 is a base having a weight that prevents the tornado protection net 1 from moving relative to the installation target or the tornado protection net 1 with respect to the installation target. It may be a pillar or a fence connected to the installation target so as not to move. The fixed end member 3 is fixed to the installation target with a strength that prevents the fixed end member 3 from being removed from the installation target when a flying object collides with the tornado protection net 1. Further, the fixed end member 3 is fixed to the installation target so that the tornado protection net 1 does not move from the installation target due to wind in a state where the tornado is generated.

  As shown in FIGS. 1 and 2, the protective net body 4 includes a first net 5, a second net 6, and a third net 7.

The first network 5 is disposed between the second network 6 and the third network 7. The structure of the first net 5 is determined as a net for receiving a relatively large flying object among the flying objects that are assumed to be wound up by the tornado and fly to the tornado protection net of the present embodiment. ing. That is, the first net 5 is knitted so as to have an opening with a predetermined opening area by a strand 5a (single wire or stranded wire) having a larger wire diameter than the second net 6 and the third net 7. It is a rare net. The material of the strand 5a of the 1st net | network 5 is not specifically limited. For example, a metal such as stainless steel may be employed as the material of the strand 5a of the first net 5.
The first net 5 also functions as a support member for supporting the second net 6 when a flying object collides with the second net 6.

The structure of the second net 6 is determined as a net for receiving a relatively small flying object among the flying objects that are assumed to be wound up by the tornado and fly to the tornado protection net of the present embodiment. ing. The second net 6 is a net for receiving a flying object smaller than the flying object received by the first net 5. That is, the second mesh 6 has a predetermined opening area that is smaller in opening area than the mesh in the first mesh 5 due to the strand 6a (single wire or stranded wire) having a smaller wire diameter than the first mesh 5. The net is knitted to have an opening. The material of the strand 6a of the 2nd net | network 6 is not specifically limited. For example, a metal such as stainless steel may be employed as the material of the strand 6a of the second net 6.
The second net 6 may have anisotropy in strength in the planar direction.

The structure of the third net 7 is determined as a net for receiving a relatively small flying object among the flying objects that are assumed to be wound up by the tornado and fly to the tornado protection net of the present embodiment. ing. The third net 7 is a net for receiving a flying object having the same size as the second net 6. That is, the third mesh 7 has a predetermined opening area that is smaller in opening area than the mesh in the first mesh 5 by the strand 7a (single wire or stranded wire) having a smaller wire diameter than the first mesh 5. This is a net knitted so as to have an opening (similar to the opening area of the mesh of the second net 6 in this embodiment). The material of the strand 7a of the 3rd net | network 7 is not specifically limited. For example, a metal such as stainless steel may be employed as the material of the strand 7a of the third net 7.
The third net 7 may have anisotropy in strength in the planar direction. When both the second net 6 and the third net 7 have anisotropy in strength in the plane direction, the second net 6 and the third net 7 have their respective anisotropies. Overlapping to cancel.

The first net 5, the second net 6, and the third net 7 have a mesh opening area so that they can appropriately receive different flying objects. For example, the wire 5a is knitted in the first net 5 so as to have an opening area that is equal to or smaller than the minimum projected area of a plate-like object or a massive object. The second net 6 and the third net 7 have the strands 6a and 7a knitted so as to have an opening area equal to or smaller than the minimum projected area of the rod-shaped object.
As an example of the plate-like material, a concrete plate having a length of 1.5 m, a width of 1 m, a thickness of 0.15 m and a mass of 540 kg can be mentioned.
As an example of the above-mentioned block, a container having a length of 2.4 m, a width of 2.6 m, a depth of 6 m and a mass of 2300 kg, or a truck having a length of 5 m, a width of 1.9 m, a depth of 1.3 m and a mass of 4750 kg is used. Can be mentioned.
Examples of the rod-shaped material include a steel pipe having a length of 2 m, a diameter of 0.05 m and a mass of 8.4 kg, and a steel having a length of 4.2 m, a width of 0.3 m, a depth of 0.2 m and a mass of 135 kg. Sawing can be mentioned.
Can be mentioned.
When a flying object having a smaller minimum projected area than the flying object shown in the above example is assumed, the size of the meshes of the second net 6 and the third net 7 is the size of the flying object. It may be set based on the size.

Next, the operation of the tornado protection net 1 of this embodiment will be described.
In the present embodiment, as shown in FIG. 3, when the flying object X1 collides with the protection net body 4 of the tornado protection net 1, the flying object having a projected area larger than the opening area of the mesh of the second net 6 is the first. 2 is caught by the protective net body 4. At this time, since the second net 6 is supported by the first net 5, the second net 6 is deformed more than the case where the first net 5 receives a flying object by the second net 6 alone. The amount is smaller. Further, even if the second net 6 is pushed by the flying object so that the strand 6a of the second net 6 enters the mesh of the first net 5, the third net 7 supports the flying object. Thus, the strand 6a of the second net 6 is difficult to cut.

  Next, as shown in FIG. 4, when a large flying object X <b> 2 that may break the strand 6 a of the second net 6 collides with the protective net body 4, the strand 6 a of the second mesh 6 can be broken. Although there is a property, flying objects do not directly collide with the first net 5 and the strands 5a of the first net 5 are difficult to cut. Moreover, since the strand 5a of the first net 5 is thicker than the strand 6a of the second net 6, the strand 5a of the first net 5 is higher in strength than the strand 6a of the second net 6. It is hard to cut. Further, the third net 7 supports the first net 5 against the force by which the first net 5 is pushed by flying objects.

  When a large projectile that may break the strand 6a of the second net 6 collides with the protective net body 4 and a part of the strand 6a of the second net 6 is cut, the second net 6 In FIG. 5, the protection performance against flying objects is lowered at the portion where the wire 6a is cut. However, since the third net 7 having the same size as that of the second net 6 is provided, the flying object penetrates the protective net body 4 and the flying object collides with the protection target object. The possibility is kept low.

  As described above, the tornado protection net 1 according to the present embodiment has the first net 5, the second net 6, and the third net 7 corresponding to the size of the flying object. Each can be taken. In the present embodiment, the meshes having two types of mesh sizes are overlapped. A larger mesh can receive a large flying object, and a smaller mesh can receive a small flying object.

  Further, the third network 7 has the same mesh as the second network 6, and even if the strand 6 a of the second network 6 is cut off, the third network 7 receives flying objects that the second network 6 should accept. 7 can catch. Thus, since the 3rd net | network 7 and the 2nd net | network 6 are piled up, the protection net main body 4 of this embodiment has high durability.

  Further, since the first network 5 is arranged between the third network 7 and the second network 6, in the present embodiment, a relatively small mesh network and a relatively large mesh network Are in a state of being alternately stacked. As a result, the second mesh 6 having a relatively small mesh on the side where the flying object collides is held by the first mesh having a relatively large mesh, and is not easily bent.

  Further, when the second net 6 and the third net 7 have anisotropy in strength in the plane direction, the second net 6 and the third net 7 have their anisotropy. Since they are overlapped so as to cancel each other, the whole structure has no anisotropy in strength in the plane direction.

(Second Embodiment)
A second embodiment of the present invention will be described. In the present embodiment, the same components as those already described in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and redundant descriptions are omitted. FIG. 5 is a cross-sectional view showing a protective net body in the tornado protective net of this embodiment. 6 and 7 are diagrams for explaining the operation of the protective net body in the present embodiment.

A tornado protection net 1A of the present embodiment shown in FIG. 5 includes a protection net body 14 having a configuration different from that of the protection net body 4 disclosed in the first embodiment.
The protective net body 14 is disclosed in the first embodiment, in which a mesh is formed by strands similar to the strands 6a of the second mesh 6 disclosed in the first embodiment, and the first embodiment. The second net 16 and the third net 17 have meshes formed of the same strands as the strands 5 a of the first net 5.
The first network 15 of this embodiment is arranged between the second network 16 and the third network 17. The mesh size of the second mesh 16 and the third mesh 17 is larger than the mesh size of the first mesh 15.

Next, the operation of the tornado protection net 1A of the present embodiment will be described.
As shown in FIG. 6, in the present embodiment, the flying object X1 having a size that can pass through the second net 16 collides with the second net 16 or collides with the first net 15. Is received by the protection net body 14. In addition, the third net 17 supports the first net 15 and the second net 16 against the force of flying objects pushing the first net 15 and the second net 16.

  Further, as shown in FIG. 7, when a large flying object X <b> 2 that may break the strands of the first net 15 collides with the protective net body 14, the strands of the first net 15 do not break. Thus, the second net 16 can protect the strands of the first net 15.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
For example, the size of the opening area of the mesh may be different between the second mesh and the third mesh.

DESCRIPTION OF SYMBOLS 1 Tornado protective net 2 Border rope 3 Fixed end member 4,14 Protective net main body 5,15 First net 5a First net strand 6,16 Second net 6a Second net strand 7, 17 Third net 7a Third net strand X1, X2 Projectile

Claims (6)

A protective net body,
A border rope attached to the protective net body;
With
The protective net body is
A first net;
A second network having a mesh different from that of the first network;
A third mesh having a mesh size of at least the opening area of the mesh of the second mesh;
With
A tornado protection net, wherein the first net, the second net, and the third net are overlapped. The tornado protection net according to claim 1,
The third net has the same mesh as the second net. A tornado protection net. The tornado protection net according to claim 2,
A tornado protection net, wherein the first net is arranged between the third net and the second net. The tornado protection net according to claim 2,
The second net and the third net have anisotropy in strength in a plane direction, and the second net and the third net cancel the anisotropy. Superposed tornado protection net. The tornado protection net according to claim 1,
The second net has a smaller mesh than the first net. A tornado protection net. The tornado protection net according to claim 1,
The second net has a larger mesh than the first net. A tornado protection net.

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