JPH05106148A - Ball protecting net - Google Patents

Abstract

PURPOSE:To ball protecting net for preventing balls of golf, baseball, tennis, etc., from flying out by making constitution wherein opposing two sides among six sides forming meshes of a net are made by combining net yarns in two directions in a yarn ribbon state, the four remaining sides are composed of net yarns in one direction alone and length of net legs of the sides of the combined yarns is <= length of other net legs of the other sides. CONSTITUTION:Net yarns A and B made of synthetic fiber filament are used in one direction and the other of mutual crossing to successively form hexagonal meshes, opposing two sides 11 and 14 among six sides constituting the meshes are combined into a yarn ribbon state by braiding or twisting net yarns A and B in one direction and the other. The remaining four sides 12, 13, 15 and 16 are composed of the net yarn A in one direction and the net yarn B in the other alone and length of the net legs of the sides 11 and 14 made of the twisting is >= length of the net legs of other sides to give a ball protecting net.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball-proof net for preventing balls such as golf balls, baseballs and tennis balls from jumping out of a stadium or a practice field.

[0002]

2. Description of the Related Art As ball-proof nets, Russell nets and knot nets made of polyethylene filament yarn are used. However, since the Russell net is thicker because each side that constitutes the mesh, that is each net leg, is made thicker by chain-knitting, the weight of the entire net is heavy and the wind pressure received is large, so it is stretched around the stadium etc. It is necessary to make the struts large when playing, and to narrow the distance between them, especially when the wind is strong, and it is necessary to lower the net, and the other side cannot be seen through the net and the scenery is bad, so the player feels a lot of pressure. There was a problem. Further, the knotted net has the same problem as the above-mentioned Russell net because the strength of the net yarn is reduced at the knotted part and the thick knotted part is increased to easily receive the wind pressure. Then, when the thread used is made thin and the net is lightened, the net is broken by the impact of the ball.

Therefore, recently, a knotless net having thin net legs and light weight is used. This knotless net is shown in Figure 2.
Is a normal type net or a penetrating type net, and each has two single yarns in one direction and the other direction intersecting with each other (however, the single yarn here is obtained by dividing a twisted yarn into two). A plurality of sets of net yarns A and B, each of which is a split yarn, may be either a straight yarn or a twisted yarn of two or more arbitrary yarns. , One side of a quadrangle is formed by individually twisting the above-mentioned net yarns A and B, and at the intersection of the net yarns A and B, the single yarns a and a of one net yarn A The single yarns b and b are combined so as to be hooked alternately, and then the above twisting is continuously performed to form a large number of square meshes.

[0004]

The above knotless ball-proof net keeps the breaking load at the same level as the above-mentioned Russell net and makes the net leg as thin as the knot net, and the crossing portion is more than the knot net. Can be made smaller. However,
At the intersection of the net yarns A and B in two directions, these net yarns A and B are
Each single yarn of is assembled to form a plain weave unit design,
Since the single yarns are only caught by each other, the single yarns a and b at the intersecting portion are easily cut by the impact of the ball, and the misalignment occurs at the intersecting portion to easily pull out the ball. If the thickness is made thicker or the mesh (the length of each side that constitutes the mesh, that is, 1/2 of the total length of the mesh legs) is shortened, it becomes heavier as described above, and especially the height at which the net is stretched as recently. When the height of the net becomes higher and it becomes even tighter on the ceiling, the net becomes heavier, and there is a problem that it is difficult to see through and the scenery becomes poor.

According to the present invention, since the mesh of the knotless net is formed into a hexagonal shape, it is light and has a low resistance to wind, is easy to see through, does not have a feeling of pressure, has a good view through the mesh, and has a pillar shape. (EN) A ball-proof net which can be narrowed in space, can be easily installed on a ceiling, does not need to be lowered even in a strong wind, and is less likely to cause misalignment.

[0006]

In the ball-prevention net of the present invention, hexagonal meshes are continuously formed by using mesh yarns made of synthetic fiber filaments in one direction and the other direction intersecting with each other. Of the six sides forming the mesh, two opposing sides are formed into a single thread string by combining the mesh yarns in the one direction and the other direction, and the remaining four sides are in the one direction or the other direction. It is characterized in that the braid is formed of the braid only and the length of the braid of the side composed of the composite of the two braids does not exceed the length of the braid of the other side.

FIG. 1 shows an example of the ball-prevention net of the present invention. A net yarn A in one direction (vertical direction) and a net yarn B in the other direction (horizontal direction) are conventional ordinary nets or As in the penetrating net, each is formed by two single yarns a, a and b, b. The filaments constituting the single yarns a, a, b and b are synthetic fiber filaments having a tensile strength of 15 g / d or more and a tensile elongation at break of 10% or less, for example, aramid fiber (trade name "Kevlar").
Toray Co., Ltd., trade name "Technora" Teijin Limited), liquid crystal polyester fiber (trade name "Vectran" manufactured by Kuraray Co., Ltd.) and ultra high strength polyethylene fiber (trade name "Dyneema" manufactured by Toyobo Co., Ltd.), especially Ultra high strength polyethylene fibers having a tensile strength of 27 g / d or more are preferred.

Six sides 11, 12 forming a hexagonal mesh,
Out of 13, 14, 15, and 16 two opposite sides 11, 1
4 are unidirectional constituent yarns a, a of the unidirectional yarn A and constituent yarns b, b of the unidirectional mesh yarn B, for a total of four single yarns a, a, b, b
A mesh yarn A in which other opposing two sides 12 and 15 are unidirectional by combining or twisting to form a string
And the remaining opposing two sides 13 and 16 are formed by twisting the constituent single yarns b and b of the mesh yarn B in the other direction.

FIG. 3 illustrates how to make the net of FIG. 1 described above. The net yarn A in one direction inclining upward to the left and the net yarn B in the other direction inclining upward to the right alternate in the figure. And the constituent single yarns a and a of the net yarn A in one direction and the constituent single yarns b and b of the net yarn B in the other direction respectively go up while twisting individually, and two sets of net yarns A, At the place where B meets each other, combine the net yarns A and B and preferably assemble them two or more times (Fig. 1).
Shows an example in which the number of sets is three, and FIG. 2 shows an example in which one is).
By twisting or twisting two or more times to form a composite, the vertical net leg C in FIG. 3 is formed. The twisting for this compounding is not the single twist a, a and the single yarn b, b which are individually twisted and then the upper twist added, but the single yarn a, a of the net yarn A and the single yarn b of the net yarn B. And b are preferably directly twisted by twisting.

Next, the four single yarns a, a, b, and b are divided into left and right parts, and the single yarns a, a, b, and b are individually twisted to form an inclined net leg. Hereafter, by repeating this,
The hexagonal mesh is created. And in this invention,
The composite length of the net yarns A and B, that is, the two opposite sides 11 of FIG.
The length of 14 is set to be equal to or less than the length of the remaining four sides 12, 15, 13, 16. The unidirectional mesh yarn A and the unidirectional mesh yarn B do not have to return to the initial direction after the twisting. For example, the number of twists may be set to 2.5 times, 3.5 times, etc., and the directions of all or some of the single yarns of both may be switched.

In the above composite part, four single yarns a,
The number of twists per unit length when twisting a, b, and b is preferably equal to or less than the number of twists per unit length when twisting two single yarns a, a or b, b on the other four sides. As shown in FIG. 4, the net obtained as described above has the net yarn A in one direction facing the vertical direction and the net yarn B in the other direction facing the horizontal direction. It is preferable that the ball-proof net is tailored to have substantially the same shape as that of the knotless net (hereinafter, referred to as a square stitch).

[0012]

Operation: Only two opposing sides 11 and 14 of the hexagonal mesh are made by combining two mesh threads A and B, and the remaining four sides are mesh threads A.
Since it is made of only B or only B, it is a ball-proof net that is light and has good transparency as in the conventional ordinary knotless net. Moreover, the above-mentioned two sides 11, 14 are two net yarns A, B
Since it is made by compounding as described above, no misalignment occurs. However, if the length of the two sides 11, 14 resulting from the combination becomes longer than the length of the remaining four sides 12, 13, 15, 16.
When the mesh size is constant, the thick net leg portion due to the combination increases, the net becomes heavy, and the wind pressure is easily received. Further, if the number of twists or the number of twists when the two net yarns A and B are combined is less than 2, misalignment is likely to occur, which is not preferable.

The above-mentioned net yarns A and B have a tensile strength of 15 g / d.
With the above filaments, the tensile strength is more than double that of the conventional ordinary polyethylene fiber of 6 g / d. Therefore, even if the thickness of the mesh threads A and B is reduced to about half of the conventional one, Breaking load becomes almost the same as conventional. When the tensile elongation at break of the filament is 10% or less, the elongation is reduced and the ball drop is reduced, and the number of twists of the net yarns A and B can be reduced to increase the strength utilization factor. It will be possible. The thickness of the above-mentioned net yarns A and B is 2500-6.
500 denier is preferable, and when it is less than 2500 denier, the breaking load is insufficient and the net is easily broken. When it exceeds 6500 denier, the net weight becomes excessive and the wind pressure is easily received, and the scenery is damaged. Furthermore, the mesh of the net is
From the viewpoint of net weight and landscape, 40-60 mm for golf and 60-80 mm for baseball are preferable.

When the above-mentioned two net yarns A and B are respectively composed of two single yarns a, a and b, b, two net yarns A, B, that is, four yarns, which are compounded by twisting, are formed. If the number of twists per unit length of the single yarns a, a, b, and b is greater than the number of twists per unit length of the other four sides, the net strength is reduced, which is not preferable. Further, when the above net is made into a square stitch (see FIGS. 1 and 4), the hanging of the mesh leg is reduced and the ball-preventing performance is improved, but the composite portion of the two mesh yarns A and B (intersection portion) ) In the vertical direction or in the horizontal direction, the mesh is easily deformed by an external force and the ball-preventing performance is deteriorated. Further, by applying a resin coating after the net making, the breakage of the net is further reduced. Further, the above-mentioned net yarn can be colored by resin coating or dyeing after the primary dyeing or net making, whereby the landscape or weather resistance can be improved.

[0015]

【Example】

Experiment 1 Multifilament yarn (1600 denier, 1560 filament, tensile strength 30 g / d, tensile breaking elongation) of ultra-high-strength polyethylene fiber (trade name "Dyneema" manufactured by Toyobo Co., Ltd.) as constituent single yarns of the net yarns A and B. 4%), and these two single yarns were used for both the unidirectional net yarn A and the other directional net yarn B, and Samples 1 and 2 (Comparative Examples 1 and 2) and Samples 3 and 4 (Examples) were used. Four types of nets 1, 2) were prototyped. The diameter of the mesh threads A and B is 1 mm, and the tensile breaking load is 57
It was kg. The results of the performance test are shown in Table 1 below.

In the table, the number of twists of the net yarn is the number of twists of the net yarn other than the composite portion, and the unit is times / mesh (when the mesh is 50 mm, the number is twist / 50 mm). Further, the number of sets of intersecting parts is the number of times of forming the intersecting part (composite part) of two net yarns A and B. When the number of sets is 1, the mesh is quadrangular, and when it is 2 or more, it is hexagonal. In addition, the number of balls dropped is set vertically by passing a rope around a 60 cm square net that has been made into square corners, and the four corners are fixed to the columns with metal fittings.
Is the number of times a golf ball is fired at a speed of 55 m / sec with a pneumatic bazooka test machine and hits the same position on the above net, and a ball drop occurs, and the number of torn balls is the bazooka test machine above. It is the number of times until the net leg is cut in the test by.

Table 1 Sample No. 1 2 3 4 Number of twists (number of turns / measuring) 30 27 30 30 Number of crossing sets 1 1 3 3 Resin coating No No No Yes No (mm) 50 45 50 50 1 4 − − Number of balls hitting the net − 6 27 100 or more Crossing deviation Large Large Small Small Wind pressure ratio 1 1.1 11 1 Net weight (kg / m ² ) 3.9 3.9 3.9 4.0 Landscape good Good good

As can be seen from Table 1 above, the sample 3 according to the first embodiment of the present invention has a small amount of misalignment at the intersection, that is, the composite portion, has no ball missing, and is hard to break.
In Sample 1 (Comparative Example 1), the number of intersections is 1 and the mesh is quadrangular. Therefore, when the mesh size is 50 mm, which is the same as Sample 3, ball dropout easily occurs. To prevent this, the mesh size is 45 mm
In Sample 2 (Comparative Example 2), which was made extremely small, the ball drop was slightly improved, but it was easily broken. And the sample 4 obtained by applying the resin coating to the net of the sample 3 (Example 2)
In addition, damage is reduced by the coating effect, and stress concentration due to non-uniform twisting is avoided, so the number of net-breaking hit balls is significantly improved.

Experiment 2 A monofilament made of ordinary polyethylene (thickness 4
00 denier, tensile strength 6 g / d, tensile elongation at break 15
%) To form net yarns A and B, and prototype nets of Sample 5 (Comparative Example 3) and Sample 6 (Example 3),
A performance test was conducted in the same manner as in Experiment 1. The results are shown in Table 2 below. The mesh yarns A and B had a diameter of 2.2 mm and a tensile breaking load of 60 kg.

Table 2 Sample No. 5 6 Number of twists (turns / measuring) 16 16 Number of crossing sets 13 No resin coating No meshing (mm) 50 50 Number of balls hitting the ball --- Number of balls hitting the net 17 73 Crossing deviation Small Small Air pressure ratio 2.2 2.2 Net weight (kg / m ² ) 16.1 16.3 Poor landscape Poor

As is clear from Table 2 above, Sample 6 having a larger number of crossed sets than Sample 5 has the characteristic of being difficult to break, but both Samples 5 and 6 have a low breaking strength. Since polyethylene fiber of No. 1 was used and the net yarn was made thicker in comparison with Samples 1 to 4, the wind pressure ratio and the net weight were larger than those of Samples 1 to 4, and the landscape was deteriorated. The number of hit balls is inferior to Samples 3 and 4.

Experiment 3 The same ultrahigh-strength polyethylene fiber net yarn as that used in Experiment 1 was used, and the number of crossing sets was variously changed within a range of 2 or more to obtain Samples 7, 8 and 9 (Example 4). 5, 6) and a net of Sample 10 (Comparative Example 4) were manufactured as prototypes and their performances were compared. The results are shown in Table 3 below. The number of twists (times /
The mesh), the resin coating, and the mesh were the same as in Sample 3.

Table 3 Specimen No. 7 8 9 10 Number of sets of intersecting parts 2 2 6 8 No resin coating No Yes No No Number of balls hitting the ball 18 78 − − Number of hitting balls of the net 20 100 or more 23 21 Crossing deviation Medium Small Small Small Wind pressure ratio 1 1 1 1.1 Net weight (kg / m ² ) 3.9 3.9 4.0 4.1 Landscape Good Good Good Bad

As is clear from the comparison between Samples 7, 9 and 10 in Table 3 and Samples 1 and 3 in Table 1, as the number of sets of intersecting parts increases, the deviation of the intersecting points becomes smaller and ball omission is eliminated. Breakage is also less likely to occur. However, the sample 9 has 6 crossing sets, and at this time, the net leg length of the crossing part, that is, the lengths of the sides 11 and 14 (see FIG. 1) formed by twisting the net yarns A and B are the remaining sides. Samples 3 and 8 have the same length as 12, 13, 15 and 16 (mesh shape is regular hexagon)
It is recognized that there is a tendency to break a little compared to. And
In the sample 10 in which the number of twists at the crossing portion was further increased and the length of the net leg was longer than the remaining four sides, the sample 10 was susceptible to wind pressure, the net weight was increased, and the landscape was deteriorated.

Experiment 4 A similar test was carried out using ultrahigh strength polyethylene fibers having a lower strength than the ultrahigh strength polyethylene fibers of Samples 1 to 4 above. That is, 2 multifilament yarns (2400 denier, 1560 filaments) of ultra-high-strength polyethylene fiber having a tensile strength of 18 g / d and a tensile elongation at break of 8% were used.
Using this, the net of Sample 11 (Example 7) and two multifilament yarns (3200 denier, 1650 filament) of ultrahigh strength polyethylene fiber having a tensile strength of 12 g / d and a tensile elongation at break of 10% were used. Sample 12
Each of the nets of (Example 8) was prototyped and a performance test was conducted. The results are shown in Table 4 below. The number of intersections, the resin coating, and the mesh were the same as in Sample 3, and the resin coating was omitted. The diameters of the net threads A and B are 1.2 mm for sample 11 and 1.4 mm for sample 12,
The tensile breaking load was 57 kg for sample 11 and 56 kg for sample 12.
Met.

Table 4 Sample No. 11 12 Number of twists (turns / measuring) 22 15 Number of intersections 3 3 Number of net breaks Hit balls 22 15 Number of crossing deviations Small 1.4 Wind pressure ratio 1.2 1.4 Net weight (kg / m ² ) 5.9 7.8 Landscape Good and bad

That is, when the tensile strength is low, the net yarn is thickened to maintain the breaking load at a predetermined level. However,
When the tensile strength is 15 g / d or more like the sample 11, the ball-proof properties such as the number of balls hitting the ball and the number of balls hitting the net almost meet the requirements, and the scenery is kept good.
As described above, when the tensile strength is reduced to 12 g / d, the ball-proof performance is slightly lowered.

Experiment 5 A multifilament yarn (1500 denier, tensile strength 22 g / d, of aramid fiber (trade name "Kevlar" manufactured by Toray Industries, Inc.) was used in place of the above-mentioned ultra high strength polyethylene fiber.
Two pieces having a tensile breaking elongation of 3.9%) were used for both the unidirectional net yarn A and the other directional net yarn B to fabricate the nets of Sample 13 (Comparative Example 5) and Sample 14 (Example 9). .. Net thread A,
The diameter of B was 1 mm and its tensile breaking load was 57 kg.
Also, a liquid crystal polyester fiber (trade name "Vectran" manufactured by Kuraray Co., Ltd.) multifilament yarn (1500 denier, tensile strength 24.5 g / d, tensile elongation at break 3.
7%) was used for both the unidirectional net yarn A and the other directional net yarn B to fabricate the nets of Sample 15 (Comparative Example 6) and Sample 16 (Example 10). The diameter of mesh threads A and B is 1 m
m, and its tensile breaking load was 59 kg. The test results are shown in Table 5 below. The number of twists is 40 times / mesh,
There is no resin coating and the mesh is unified to 50 mm.

Table 5 Sample No. 13 14 15 16 Number of crossing combinations 1 3 1 3 Number of ball hitting balls 1-1 − Net number of ball hitting balls − 15 − 18 Cross point deviation Large Small Large Small Wind pressure ratio 0.7 0.7 0.7 0.7 Net weight ( kg / m ² ) 3.8 3.8 3.8 3.8 Landscape Good Good Good

Even when the aramid fiber and the liquid crystal polyester fiber are used, the wind pressure ratio is 0.7 because the tensile strength is large as in the case of the ultra high strength polyethylene fiber.
It was extremely low, the net weight was light at 3.8 kg / m ² , and the landscape could be maintained well. However, when the number of intersections is 1, the deviation of the intersections is large and the ball-proof property is poor. On the other hand, when the number of intersections is 3, the ball-proof property is significantly improved.

Experiment 6 The scale was changed from 50 mm to 75 mm, and the ball-proof property of a hardball was tested. That is, the nets A and B of ultra-high-strength polyethylene fibers same as those of Samples 1 to 4 were used to fabricate the nets of Sample 17 (Example 11) and Sample 18 (Comparative Example 7) having meshes of 75 mm. In addition, using the same ordinary polyethylene fiber mesh as that of Sample 5, Sample 19 (Comparative Example 8) having a mesh of 75 mm was manufactured. In the ball-proof test, the rope was vertically set up around the 2m square net that was made like the above, and the four corners were fixed to the columns with metal fittings.
A hard baseball was shot at a speed of 39 m / sec from a distance of 1 m from this net by a pitching machine, and was hit at the same position on the net, and the number of times until the cutting of the net legs occurred was examined. The results are shown in Table 6 below.

Table 6 Specimen No. 17 18 19 Number of twists (turns / measuring) 30 30 16 Number of crossing sets 3 1 1 1 Resin coating Yes Yes No Number of net struck balls 30 or more 10 30 or more Crossing deviation Small Large Small Wind pressure ratio 1.1 1.1 2.2 Net weight (kg / m ² ) 3 3 12.1 Landscape good Good bad

As is clear from Table 6 above, in Samples 17 and 18 using the same ultra-high-strength polyethylene fiber, while the various characteristics of Sample 17 in which the number of crossing sets is set to 3, are excellent, The sample 18 in which the number of subassemblies was set to 1 had a large deviation of the intersection and was inferior in the ball-proof property. In addition, since the sample 19 using the normal polyester fiber having a low tensile strength has a thick net yarn, the net weight and the wind pressure ratio are large and the landscape is poor.

Experiment 7 The number of high-strength polyethylene fiber multifilament yarns (1600 denier, 1560 filaments) used in Experiment 1 was increased from 2 to 4 to form mesh yarns A and B. Sample 20 (Comparative Example 9) ), Sample 21 (Example 12) and Sample 22 (Example 13) were prototyped, the size of the net was reduced to 1 m square in comparison with Experiment 1, and the golf ball speed was 43 m / sec. The test was performed using a bazooka test machine as in Experiment 1, except that the speed was reduced. The results are shown in Table 7 below.
Shown in. The diameter of the net yarns A and B are both 1.5 m.
The m and tensile breaking load were 115 kg.

Table 7 Specimen No. 20 21 22 Number of twists (times / measuring) 30 30 30 Number of crossing sets 1 3 3 Resin coating Yes No Yes Meaning (mm) 45 50 50 Number of balls missing 1021-Net breaking Number of hits 11 54 300 or more

That is, Sample 2 in which the net yarns A and B are thickened
In Nos. 1 and 22, the ball-proof property is significantly improved, but in Sample 20 having a square mesh and a small mesh, Samples 21 and 2 are used.
Although the same net yarns A and B as those of No. 2 are used, the above properties are low.

Experiment 8 Net yarns A and B composed of 36 monofilament yarns (400 denier) of ordinary polyethylene fibers used in Sample 5
Using the net of Sample 23 (Comparative Example 10), and using the net yarns A and B composed of two multifilament yarns (1600 denier) of the ultra-high-strength polyethylene fibers used in Samples 1 and 2 24 (Comparative Example 11), Sample 25
Each of the nets of (Example 14) was prototyped. And
A square 2m square net was stretched at a distance of 7m from the robot striking machine at an inclination angle of 30 degrees with respect to the vertical plane and at a low level in front, and a ball of 61
The number of hits until the net was broken was compared by firing at a speed of m / sec. The results are shown in Table 8 below.

Table 8 Sample No. 23 24 25 Number of twists (times / measuring) 30 30 30 Number of crossing sets 1 1 3 No resin coating Yes Meaning (mm) 50 45 45 Number of net struck balls 16 3 50 or more

Also in this test, the number of sets of intersecting parts is 1 between Sample 24 and Sample 25 which differ only in the number of sets of intersecting parts.
The sample 24 having a square mesh of 3 is easily damaged, whereas the sample 25 having a hexagonal mesh with the number of sets of intersections being 3 is less likely to be damaged. In addition, sample 23 uses normal polyethylene fiber and has the number of crossed parts set to 1, but since the net thread is thick, the mesh is large, and the resin coating is omitted, The impact is relieved and the ball is less likely to break, but the ball is more likely to come off.

Experiment 9 Sample 26 (Example 15) and Sample 27 (Example 16) were prepared in the same manner as in Experiment 1 except that the composition at the crossing portion was carried out by twisting the constituent single yarns of the net yarns A and B together. A net was prototyped and tested in the same manner as Experiment 1. The results are shown in Table 9 below.
Shown in. The number of twists at the intersection in the table is the actual number of twists for the above composite.

Table 9 Sample No. 26 27 Number of twists (times / measuring) 30 30 Number of twists at intersection 3 3 No resin coating Yes Meshing (mm) 50 50 Number of net breaks Hitting ball 22 15 Cross point deviation Small Small Wind pressure ratio 11 Net weight (kg / m ² ) 3.9 4.0 Landscape good

That is, the displacement of the intersection can be reduced and the net strength can be improved almost in the same manner as in the case where the combination of the intersections is performed in combination.

As described above, the ball-preventing net of the present invention is a knotless net having a hexagonal mesh formed by using mesh yarns in two directions and facing each other among the six sides forming the mesh. The two sides are formed by combining net yarns in two directions in a string shape, and the remaining four sides are formed by net yarn in one direction alone, and the net length of the above-mentioned combined side is the net of the other side. Since it is set to a leg length or less, it is light, has little resistance to wind when it is stretched in a stadium, etc., it is easy to see through, there is no feeling of pressure, and the landscape through the mesh is good, and the prop The effect of being able to narrow the space between, is easy to install on the ceiling, does not need to be lowered even in strong winds, is less likely to cause misalignment, and is unlikely to cause ball loss or tearing.

[Brief description of drawings]

FIG. 1 is an enlarged view of a mesh according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a mesh of a conventional ball-proof net.

3 is a schematic diagram illustrating how to make the net of FIG. 1. FIG.

FIG. 4 is an explanatory view showing how to stretch the net shown in FIG.

[Explanation of symbols]

 A, B: Net yarn a, b: Single yarn 11, 14: Side formed by combining net yarns A and B 12, 15: Side formed by unidirectional net yarn A alone 13, 16: Other Side formed by the net thread B alone

Claims (3)

[Claims] 1. Hexagonal meshes are continuously formed by using mesh yarns made of synthetic fiber filaments in one direction and the other direction intersecting each other, and two hexagonal meshes facing each other are opposed to each other. The side is formed into a single thread string by compounding the above-mentioned one-direction and the other-direction mesh yarns, and the remaining four sides are formed by the above-mentioned one-direction or other-direction mesh yarns alone, and the above-mentioned two meshes A ball-proof net characterized in that the length of the braid on the side composed of the yarn does not exceed the length of the braid on the other side. 2. The tensile strength of the synthetic fiber filament is 1
The ball-proof net according to claim 1, which has a tensile elongation at break of 5 g / d or more and 10% or less. 3. The synthetic fiber filament has a tensile strength of 27.
An ultrahigh strength polyethylene fiber having a g / d or more.
Or the ball-proof net according to 2.