JP3038751U - Birdproof thread and birdproof construction - Google Patents

Abstract

(57) [Abstract] [Problem] To provide a bird-proof yarn and a bird-proof structure that not only prevents bird invasion but also makes installation work simple, and that humans can easily enter, exit, manage, and handle after installation and has a good appearance. To do. SOLUTION: The bird-prevention yarn is made of a transparent synthetic resin monofilament and has a portion whose thickness changes in the length direction. The birdproof structure includes a plurality of upright supports and the birdproof thread stretched between the supports.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 TECHNICAL FIELD The present invention relates to a bird-prevention yarn having an increased glittering feeling and a bird-prevention structure using the same.

[0002]

[Prior art]

 In order to prevent damages such as birds invading farmland and damaging field crops, invading balconies and balconies and being polluted with excrement, and being caught in power transmission towers and power poles, causing electric shock and stopping power distribution, A bird-prevention net is used to prevent birds from approaching or entering, so-called bird shelter. This bird-prevention net is highly effective in preventing birds from entering due to its net-like shape.

[0003]

[Problems to be solved by the device]

 However, since the bird-prevention net must be spread in a net-like shape and stretched, it takes a lot of time and labor to install the bird-prevention net. It has the drawbacks that it is difficult to do the necessary work, management and handling are troublesome, and that installing a net on a veranda or balcony does not give a sense of liberty to humans and makes the external appearance worse.

Therefore, the present invention has a large glittering feeling and can prevent the approach and invasion of birds, the installation work is simple, and human beings can easily enter and exit after installation, and can be managed and handled. An object of the present invention is to provide a bird-proof yarn and a bird-proof structure that are easy and have little adverse effect on the feeling of freedom and appearance.

[0005]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the inventor firstly installs the thread used in the net or the like in order to make the installation work easier than that in the case of the net, and to make it easier for people to enter and exit after the installation. I thought that it would be better to stretch several books linearly. However, even if the threads are simply stretched in a straight line, the new problem arises that the bird's invasion becomes spatially easier than in the case of the net.

Therefore, as a result of diligent studies, the inventor has found that in order to solve the above-mentioned problems, it is preferable to use a thread that prevents the bird from being surprised and vigilant and does not approach in view of the habit of the bird. We have found that a fine thread, which has the property of giving off glitter and shine when received (glossiness), is good. Birds are wary when the thread receives light and shines brightly. Even if a bird gets used to it and approaches it, if the thread is thin, the bird is difficult to see, which makes it easier to catch the body and makes it difficult to obtain a learning effect. become. For human beings, the thread itself is hard to see just by shining brightly, so it does not spoil the aesthetics. However, the thickness of the thread is preferably thin from the viewpoint that it is difficult to see, but is preferably thick from the viewpoint of the strength to stretch the thread linearly as long as possible. Considering the ease of use and management of the thread, and the like, a thread made of a transparent synthetic resin monofilament is suitable as the above thread.

[0007] The inventor has further studied, and the synthetic resin monofilament has a thickness in the longitudinal direction so that the yarn easily emits a glittering brilliance when exposed to light and the yarn is more easily managed. Thought to change. A synthetic resin monofilament that has a portion whose thickness changes in the length direction easily changes its thickness and tends to be twisted, so that when it receives light, it tends to emit a glittering sparkle in various directions. At the same time, the resistance to stress is likely to be strong and the cutting strength is likely to be high. Therefore, by changing the thickness in the length direction, the effect of being surprised and vigilant for the bird is enhanced, and the effect of facilitating the management is also enhanced, which is suitable as a bird-prevention yarn.

The inventor further advanced the study, and when the yarn receives light, the yarn strongly emits a glittering shine, and moreover, the yarn is easily wound and the storability in a bobbin is improved. In order to increase the flexibility and resilience of the yarn, which is necessary to make it easy to handle, we considered adding some innovation to the cross-sectional shape of the synthetic resin monofilament. That is, it was conceived to form a shape having a constriction at the center of the cross section. As a result, a synthetic resin monofilament thread with a constriction in the center of the cross section has a more brilliant shine when exposed to light, as compared to a synthetic resin monofilament thread with a circular cross section, and is flexible / resilient. It was found to increase the sex.

Further, the inventor further stretches the bird-prevention yarn linearly as long as possible in relation to the relationship between the length and the thickness of the monofilament whose thickness changes in the length direction and the cross-sectional dimension of the monofilament having the cross-sectional shape. Therefore, consideration was also given to the strength required. It is said that the relationship between the length and the thickness and the cross-sectional dimension of the portion where the thickness is changed in the length direction may affect whether or not the bird proof yarn is likely to emit a glittering shine when receiving light. Not only is there a problem, but the fact that it is difficult to see the bird-proof yarn itself makes the maximum diameter of the largest part a problem, and it is necessary to stretch the bird-proof yarn linearly as long as possible. This is because the minimum diameter of the minimum thickness part becomes a problem from the viewpoint of strength.

On the other hand, in order to stretch the yarn linearly and prevent invasion of birds, it is necessary to devise a way of tensioning the yarn in addition to the yarn itself. The inventor also diligently studied this issue. As a result, we noticed that crows, which tend to damage birds, especially crops and humans, often glide horizontally rather than ascend and descend vertically. And I thought about arranging the threads stretched low in parallel.

As a result of further studies based on these examination results, the inventor has completed the present invention as a bird-prevention yarn capable of solving the above-mentioned problems and a bird-prevention structure using the same. . Therefore, the bird-prevention yarn of the present invention is made of a transparent synthetic resin monofilament and has a portion whose thickness changes in the length direction.

The portion where the thickness changes in the length direction may be a portion where the thickness continuously increases and decreases in the length direction. It is preferable that the portion where the thickness continuously increases and decreases in the lengthwise direction has a constriction at the center of the cross section. In the portion where the thickness continuously increases and decreases in the lengthwise direction, the maximum diameter of the minimum thickness portion is 0.1 to 0.4 mm, and the maximum diameter of the maximum thickness portion is 0.2 to In addition to being 1.0 mm, there is a 1.5 to 3 times difference between the maximum diameter of the maximum thickness part and the maximum diameter of the minimum thickness part. Furthermore, the length from the minimum thickness part to the maximum thickness part is It is preferably in the range of 1 to 10 m.

The bird-prevention structure of the present invention comprises a plurality of upright columns, and any of the above-mentioned bird-prevention yarns stretched between the columns. In the bird-prevention structure, the plurality of columns are composed of two types, high and low, and the high columns and the low columns are alternately arranged. The high columns and the high columns are stretched over from the ground, and the low columns and the high columns are high. Between the space and / or between the low struts, it is preferable that they are stretched low from the ground, and the high-stretched bird-proof yarn and the low-stretched bird-proof yarn are alternately arranged substantially in parallel.

[0014]

[Embodiment of the invention]

 An embodiment of the present invention will be described below with reference to FIG. 1, which shows two examples of cross-sections along the length direction of the bird-preventing yarn, FIG. 2 which shows four examples of schematic cross-sections of the bird-preventing yarn, and the appearance of the bird-preventing yarn. The present invention will be described with reference to FIG. 3 and FIG. 4 showing an example of the appearance of the bird protection structure, but the present invention is not limited to the following embodiments.

Regarding the bird-proof yarn composed of the transparent synthetic resin monofilament of the present invention, the change in thickness in the length direction can be roughly classified into continuous change and discontinuous change. It may be. As a form of the continuous change, for example, as shown in the bird-proof yarn 10 in FIG. 1 (a), the thickness is the smallest (diameter D ₁ ) within a constant length L ₁ in the length direction. It continuously increases and reaches the maximum (diameter D ₂ ), and subsequently, the thickness continuously decreases for a certain length L ₂ (L ₂ = L _{1 in} this example). An example is a mode in which the state of becoming the minimum (diameter D ₁ ) again is repeated without an interval. The form in which the continuously increasing and decreasing state is repeated becomes a bellows-like form when the length (L ₁ + L ₂ ) from the minimum thickness to the maximum thickness and again to the minimum thickness is shortened. Become. The lengths L ₁ and L ₂ can be equal or different. As an example of the form of the above-mentioned discontinuous change, as shown in the bird-proof yarn 10 of FIG. 1 (b), the collar-shaped protrusions T ₁ , T ₂ , ... An example is a form in which L ₃ , L ₄ , ... Are opened. In this case, the thickness of the bird-proof yarn intermittently changes to the minimum (diameter D ₁ ), the maximum (diameter D ₂ ), and the minimum (diameter D ₁ ).

It is also possible to add a twist to the synthetic resin monofilament to give a spiral thickness change. The change in thickness may be caused by a large number of wart-shaped convex portions formed on the peripheral surface, and the shape thereof is not limited. The bird-proof yarn made of a transparent synthetic resin monofilament having a portion whose thickness changes in the lengthwise direction can be specifically obtained by the following method. In one example, a transparent synthetic resin monofilament-forming material is extruded from the spinneret's small holes (spinning nozzle) by the melt spinning method, and when the extruded melt continues to cool and solidify, or to cool. After being solidified, there is a method of stretching it in the stretching step while continuously and gradually changing the stretching ratio or while intermittently changing it. In addition, when a transparent synthetic resin monofilament-forming substance is extruded from the small holes (spinning nozzle) of the spinneret by the melt-spinning method, the pressure to be extruded is continuously changed gradually or intermittently. There is also a method of extruding, and a method of extruding while continuously and gradually changing the thickness of the spinning nozzle, or by intermittently changing the thickness, the spinning nozzle is rotated in the circumferential direction at the same time as extrusion by these methods. There is also such a method.

In the portion where the thickness continuously increases and decreases in the lengthwise direction, the maximum diameter of the minimum thickness portion is 0.1 to 0.4 mm, and the maximum diameter of the maximum thickness portion is 0. .2 to 1.0 mm, and there is a 1.5 to 3 times difference between the maximum diameter of the maximum thickness portion and the maximum diameter of the minimum thickness portion. The length is preferably in the range of 1 to 10 m. However, the dimensional relationship in the present invention is not limited to this. Since a more preferable cross-sectional dimension (diameter) can be changed according to the cross-sectional shape, it will be described in detail in the following description of the cross-section.

Although the cross section of the bird-preventing yarn of the present invention is arbitrary, for example, it can be a single circle as shown in the bird-preventing yarn 10 of FIG. 2 (a). In the case of a single circle in cross section, the diameter (diameter 2 R) of the smallest part of the thickness is 0.1 to 0.3 mm and the largest part of the part where the thickness continuously increases and decreases in the above-mentioned length direction. The diameter (diameter 2R) is 0.3 to 0.5 mm, and the length from the minimum part to the maximum part of the thickness is in the range of 1 to 10 m. It is preferable from the standpoint of strength required to stretch the wire and making the bird-proof yarn itself hard to see. Regarding the thickness, it is most preferable that the diameter of the smallest portion is 0.2 mm and the diameter of the largest portion is 0.4 mm.

When the bird-prevention yarn of the present invention has a constriction in the center of its cross section, as a specific example thereof, two substantially perfect circles as shown in the bird-prevention yarn 10 of FIG. 2 (b). The cross-sectional shape as if they were connected to each other, the cross-sectional shape as if two substantially vertical ellipses are connected as shown in the bird-proof thread 10 in FIG. 2 (c), as shown in the bird-proof thread 10 in FIG. 2 (d). A cross-sectional shape such as connecting two peaks can be mentioned, but the present invention is not limited to these examples. In the cross section, the constriction angle is acute (k ₁ and k _{2 in} FIG. 2B), orthogonal (k ₃ and k _{4 in} FIG. 2C), and obtuse (k _{6 in} FIG. 2D). ). When there are multiple constrictions, the sectional shapes of the constrictions may be the same (k ₁ and k ₂ in FIG. 2 (b), k ₃ and k _{4 in} FIG. 2 (c)) or different (FIG. 2). (D) k ₅ and k ₆ ) can be done. In the case where the cross-section has a constriction in the central part, the true central part includes not only the true central part but also the case where the true central part deviates from the true central part. The number of the constrictions and the shape of the constriction are arbitrary with respect to the selection of the suitable number of the constrictions and the suitable cross-sectional shape of the constriction.

The thickness change in the length direction and the cross-sectional shape can be appropriately combined. FIG. 3 shows an example of this combination. A bird-prevention yarn obtained by combining the example of FIG. 1 (a) for the change in thickness in the length direction with the example of FIG. 2 (b) for the cross-sectional shape is shown. Show. In the case of this bird-proof yarn 10, the maximum diameter (H ₁ ) of the minimum thickness portion is 0.1 to 0.3 mm, and the maximum diameter (H ₂ ) of the maximum thickness portion is 0.6 to 1.0 mm. However, it is preferable from the viewpoint of the strength required to stretch the bird proof yarn linearly as long as possible and the point that the bird proof yarn 10 itself is difficult to see. Regarding the thickness, it is most preferable that the maximum diameter of the minimum portion is 0.4 mm and the maximum diameter of the maximum portion is 0.8 mm.

As an example of a method of setting the bird-proof yarn in the thickness range and the length range, for example, the diameter of the spinning nozzle is set to a constant value, and the length of the monofilament is increased in the drawing step. There is a method of continuously and gradually changing the draw ratio within a range of 1 to 10 m, or intermittently changing the draw ratio. In addition, when the monofilament is extruded from the spinning nozzle by the melt spinning method, the diameter of the spinning nozzle is continuously and gradually changed within the range of 1 to 10 m, or There is also a method of intermittently changing and pushing out.

In the bird-preventing yarn having a constriction at the center of the cross section as described above, the shape of the spinneret is formed by connecting two small holes (spinning nozzles) at the tip of each spinning outlet. After the transparent synthetic resin monofilament is extruded from the nozzle with a shape like this by the melt spinning method (in this process, the transparent synthetic resin monofilament has a constriction in the center of the cross section), the extruded synthetic resin The monofilament is stretched while gradually or intermittently changing the stretching ratio in the stretching process (in this process, the transparent synthetic resin monofilament has a portion whose thickness varies in the longitudinal direction). Naru) method.

The transparent synthetic resin monofilament targeted by the present invention is a polyester monofilament, especially polyethylene terephthalate monofilament, especially polyethylene terephthalate molybdenum obtained by two-stage drawing and heat treatment of an unstretched monofilament consisting of polyethylene terephthalate and modified polyethylene terephthalate. Nofilament is most suitable. Polyethylene terephthalate excels in the tensile strength (tensile strength) required to stretch the yarn in a straight line without sagging, and it has the necessary friction strength to make it difficult to break even if people or birds contact the yarn and repeatedly rub it. In addition to its high-strength property that it is excellent in impact strength required to make it difficult to break even if a bird or the like collides with the thread, it has low elongation, is light, and has low water absorption for rainfall, water sprinkling, etc. Since it has excellent properties such as high resistance to embrittlement against ultraviolet rays and chemicals, strong resistance to microorganisms and no need for antiseptic treatment, it is the most excellent material for bird-proof yarn. In order to make this polyethylene terephthalate transparent and glossy, it is possible to heat the unstretched monofilament consisting of polyethylene terephthalate and modified polyethylene terephthalate in two stages and heat-treat it. As a method of stretching the yarn between the struts, a knot is formed when the yarn is tied to the stanchion. In that case, it is preferable that the knot strength with respect to tension and impact is large. In this regard, the two-stage drawing and heat treatment method can increase the knot strength against the tension of the yarn without impairing the linear strength of the yarn, and the knot strength against impact can be remarkably excellent. It is also suitable for linearly stretching the yarn between them without sagging and for preventing the knot of the yarn on the strut from loosening or coming off when a bird hits the yarn. Here, the unstretched monofilament comprises 100 parts by weight of polyethylene terephthalate and 5 to 130 parts by weight of modified polyethylene terephthalate having a molar ratio of terephthalic acid component: isophthalic acid component of 98: 2 to 82:18. Is preferred. In the two-stage stretching, it is preferable to stretch at a temperature of 85 to 105 ° C. for 2.5 to 4.3 times, and further to stretch at a temperature of 180 to 270 ° C. for 1.5 to 2.5 times. . The heat treatment is preferably performed at a coiling ratio of 0.9 to 1.0 times in a gas atmosphere of 180 to 270 ° C.

However, the kind of the synthetic resin monofilament used in the present invention is not limited to the above-mentioned polyethylene terephthalate monofilament. For example, polyamide fiber such as nylon originally has high gloss and very strong tensile friction and the like. Therefore, since olefin fibers such as polypropylene and polyethylene are originally transparent, have gloss and have high strength, these monofilaments are also suitable, and synthetic resin monofilaments other than these can also be used.

The bird proof yarn of the present invention may be stored on a reel or the like for convenience of transportation and use without taking up much storage space. The installation of the bird-prevention yarn of the present invention is performed by arranging a plurality of columns upright around the installation target location and linearly stretching the bird-prevention yarn between the columns. There are various places where bird-proof yarns can be installed, such as rice fields and fields, transmission towers and poles, balconies and balconies, and eaves. The form (shape, pattern, color, etc.), height, material, etc. of the pillar is not particularly limited. Stranding of the bird-proof yarn is performed, for example, by tying the bird-proof yarn to the column (forming a knot). In order to stretch the bird-prevention yarns in different vertical heights in a substantially parallel manner, the columns may have the same height or two types of height, but each column has a long length in advance. If the columns are made common by providing through holes for threading at regular intervals in the direction, it is convenient when the threads are stretched in parallel. The method of constructing the pillars differs depending on the installation location (fields, telephone poles, etc.) of the bird-prevention thread as described later. If the number of bird-prevention threads to be stretched is too large, it is rather complicated and people are prevented from entering and leaving, so it is preferable to stretch one to several threads between two columns. The distance between the upper and lower bird-prevention yarns is preferably about 50 to 150 cm in consideration of crows, for example, so as to prevent birds from passing by horizontal gliding. It takes a certain amount of force to stretch it in a straight line, but it can be easily done with a small amount of force by using a winding device.

As a specific bird-prevention structure, for example, in a field, a low pillar is constructed by digging holes at four corners of a square section with one side of 10 to 30 m to build a low pillar so that the ground height is 1 to 2 m. In the meantime, one or two bird-prevention yarns should be placed at the same ground clearance (if there are multiple yarns, they should be generally evenly spaced up and down) and should be stretched in a generally horizontal direction without slack. High struts are built between the low struts, and 1-2 bird proof yarns are also stretched between the high struts without sagging, but the height of the stretch is higher than that between the low struts. Stretch it so that it is almost parallel to the thread stretched between the low columns. The thread stretched between the low struts is stretched so as to pass through the high struts. The above ground height of the pillar must be higher than the height of the crop, but it is empirically preferable that the above ground height is useless because it is useless. If the field is large, the bird-prevention structure can be extended and expanded. The extension and expansion method may be performed by providing square or rectangular sections adjacent to each other vertically or horizontally with one side of the square being common and straddling the bird-prevention thread in the same manner as described above. If the adjacency is continued, it can be extended and expanded. On balconies and balconies, columns are built at both ends of the handrail so that they are higher than the height of the handrail, and they are fixed with metal fittings, etc., and the bird-prevention thread of the present invention is stretched between the columns without sagging as in the field. hand over. For utility poles, attach brackets to the outer perimeter of the arms where transformers, etc. are placed, and then attach pillars to the brackets to secure the poles between the poles. Stretch the threads as in the field, without sagging.

[0027]

【Example】

 Hereinafter, embodiments of the present invention will be described. —Example 1— A transparent polyethylene terephthalate monofilament, which was subjected to a continuous change in the draw ratio in the drawing process, so that every 3 m in the length direction, as shown in FIG. 1 (a). In addition, a bird-proof yarn was manufactured in which the thickness was continuously increased from 0.2 mm to 0.4 mm, and then continuously decreased again to 0.2 mm. The cross section of this bird-proof yarn is a single circle as shown in FIG.

Next, the bird-prevention yarn was cut into a length of 100 m, wound on a reel and temporarily stored, and then carried to a field in which a crop such as a crow was damaged by crops. As shown in FIG. 4, a hole is dug at four corners of a part of the field (substantially square with one side L _{20 having} a length of 20 m), and low pillars 2 are built in the holes at the four corners. In the middle of 2, I built a high pillar 1. At that time, the low pillar 2 was built so that the ground height was 1 m, and the high pillar 1 was 2 m above the ground. All of these stanchions are wooden and rod-shaped, and the high stanchion 1 has a total length of 2.5 m, the low stanchion 2 has a total length of 1.5 m, and the high stanchion 1 has a distance h ₁ (about ₁ m) to h from the bottom. ₄ (about 2.5 m) at regular intervals, and the low post 2 has holes 3 through which the thread is threaded at equal intervals at positions h ₁ (about ₁ m) and h ₂ (about 1.5 m) from the bottom. Was set up. The distance between the holes is the same as the vertical distance between the birds when the bird-prevention yarn is stretched over, and although it differs depending on the type of bird, in this example, the crows are unlikely to invade by gliding, and The distance was set to about 50 cm in consideration of the easy access. Next, the bird-prevention thread 10 is inserted into each hole 3 of the low support column 2 and the high support column 1 so that the bird-prevention thread is stretched in a substantially parallel manner on each side of the approximately square field, respectively. The inserted bird-prevention yarn 10 was tied to the support pillars 2 around the holes 3 of the support pillars 2 having low four corners and stretched linearly around the field. Between the high stanchions 1, the bird proof thread 10 is inserted into the hole 3 so that the bird proof thread 10 is stretched in a straight line so that the bird proof thread is stretched in high parallel to each side of the approximately square field. At the periphery of the hole 3 of the high pillar 1 on each side, the inserted bird-prevention yarn 10 was tied to the pillar 1. By these operations, the low-stretched bird-proof yarn and the high-stretched bird-proof yarn were alternately arranged substantially in parallel. The bird-prevention structure in this case is the smallest structural example, and as shown in FIG. 4, it is possible to continuously extend and expand in the vertical and horizontal directions from the smallest structural example depending on the desired size of the installation.

When observed in the field, it was confirmed with the naked eye that the bird-prevention yarns strongly emitted a glittering brilliance upon receiving light, and it was recognized that birds such as crows tended to avoid this. No invasion into the stretched plot, and no bird damage to the plot within the plot. Outside of the plot, birds such as crows still invaded and caused damage to the crops. That is, the invasion of birds could be prevented inside the compartment, but the invasion of birds could not be prevented outside the compartment. Even if a bird accidentally collided with this bird-prevention thread, the bird-prevention thread was not cut.

Example 2 Example 2 is also a bird-proof yarn made of transparent polyethylene terephthalate monofilament, but the point different from Example 1 is that the bird-proof yarn as shown in FIG. 3 is used. That is, the cross section has a shape with a constriction in the center as if two circles are connected, and the thickness is 0.2 mm (A ₁ ) and the width is 0.4 mm for every 3 m in the length direction. From (H ₁ ), the thickness continuously increases to 0.4 mm (A ₂ ) and the width 0.8 mm (A ₂ ), and then again, the thickness 0.2 mm (A ₁ ) and the width 0.4 mm (H ₁ ). The point is that the bird-proof thread is designed to be continuously reduced.

This bird-prevention yarn was temporarily stored as in Example 1, and was carried to the same field as the one in Example 1 where damage was caused by the bird, and the same bird-prevention structure as in Example 1 was constructed. As a result of Example 2, it can be confirmed with naked eyes that the bird-preventing yarn emits a glittering brilliance more strongly in response to light, as compared with the case of Example 1, and the bird further avoids this. When the bird-prevention yarn is wound up in a round shape, the bird-prevention yarn does not bounce around in pieces and tends to be rounded. Others were the same as in the case of Example 1.

Example 3 The example 3 is different from the examples 1 and 2 in that it is a bird-proof yarn made of transparent polypropylene monofilament, and the thickness change of FIG. The point is a bird-proof yarn in which the cross section of (d) is combined. The dimensional relationship is that the thickness continuously increases from a thickness of 0.2 mm (A ₁₃ ) and a width of 0.4 mm (H ₁₃ ) to a thickness of 0.4 mm and a width of 0.8 mm for each 3 m length. And then continuously decreases again to a thickness of 0.2 mm (A ₁₃ ) and a width of 0.4 mm (H ₁₃ ). The results of this Example 3 were similar to those of Example 2.

[0033]

[Effect of the invention]

 The bird-prevention yarn of the present invention tends to shine and shine when the yarn is exposed to light, and thus alerts the bird and prevents the bird from approaching or entering. Therefore, the bird-preventing effect lasts for a long time, and there is no need to attach reflective tape to the thread or apply reflective paint. The birdproof yarn of the present invention has high cutting strength and is easy to manage. It is also easy to stretch in a straight line. When the yarn is stored with increased flexibility and resilience, it fits well in the bobbin and the yarn is easy to handle.

The bird-prevention yarn of the present invention simplifies the installation work of the bird-prevention structure and can be used so that a person can easily enter and exit after the installation, and does not adversely affect the feeling of liberation and the appearance impression. The bird-prevention structure of the present invention requires only a small number of threads, columns and fulcrums to be used for installation, so installation work is extremely easy and the time and labor required for the work are also small. In the bird-prevention structure, the plurality of struts are of two types, high and low, and high struts and low struts are alternately arranged. The bird proof thread is stretched high from the ground between high struts, and low struts and high struts. In the case where it is stretched low from the ground between the struts and / or between the low struts, and the high-stretched bird-proof thread and the low-stretched bird-proof thread are alternately arranged substantially in parallel. , In addition to the above effects, gliding birds cannot glide, so they cannot penetrate any more.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view taken along the longitudinal direction, showing an embodiment of the bird-prevention yarn of the present invention.

FIG. 2 is a sectional view showing an embodiment of the bird-prevention yarn of the present invention.

FIG. 3 is a perspective view showing an embodiment of the bird-prevention yarn of the present invention.

FIG. 4 is a perspective view showing an embodiment of the bird-prevention structure of the present invention.

[Explanation of symbols]

k ₁ ~ k ₆ bird-proof thread Constriction of cross section 1 high pillar 2 low pillar 3 threading hole 10 bird thread

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Yoshiyuki Ohara 559 Yura-cho, Sumoto-shi, Hyogo Prefecture Gosen Co., Ltd. (72) Creator Tayo Nagano 559 Yura-cho, Sumoto-shi Hyogo Prefecture Gosen Co., Ltd.

Claims (6)

[Utility model registration claims] 1. A bird-prevention yarn comprising a transparent synthetic resin monofilament and having a portion whose thickness changes in the length direction. 2. A portion in which the thickness changes in the length direction is a portion in which the thickness continuously increases and decreases in the length direction.
The described bird-proof thread. 3. The bird-preventing yarn according to claim 1, which has a constriction in the center of the cross section. 4. In a portion where the thickness continuously increases and decreases in the length direction, the maximum diameter of the minimum thickness portion is 0.1 to 0.
4mm, the maximum diameter of the largest part is 0.2-1.0mm
In addition, there is a difference of 1.5 to 3 times between the maximum diameter of the maximum part of the thickness and the maximum diameter of the minimum part, and the length from the minimum part of the thickness to the maximum part is 1 to 10 m. The bird's yarn according to claim 2 or 3, which is in the range. 5. A bird-prevention structure comprising a plurality of vertically-arranged columns and the bird-prevention yarn according to any one of claims 1 to 4, which is stretched between the columns. 6. A plurality of struts are of two types, high and low, and high struts and low struts are alternately arranged. Bird-proof yarn is stretched high from the ground between high struts, and between low struts and high struts. 6. The bird-prevention structure according to claim 5, wherein the bird-struts are stretched low from the ground between the low columns and / or the high-strength bird-prevention yarns and the low-extension bird-prevention yarns are alternately arranged substantially in parallel. .