JP3530589B2 - Fishing net - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fishing net such as a gill net or a tangle net.

[0002]

2. Description of the Related Art Conventionally, as synthetic fibers used for fishing nets such as gill nets or leash nets, nylon monofilaments or multifilaments have been used because strength is required for that purpose. The fishing net was manufactured by dyeing the net knitted by the method such as double knot and multiple knot.

[0003]

However, the above-mentioned fishing nets, although having sufficient strength, were not able to obtain the expected catches. This has traditionally been thought to be necessary to prevent the nodules from shifting due to caught fish and shrimp in order to increase the catch, and to contact rocks when pulling up the fishing net. Since we were required to have a durable net because it could be torn, we are constantly trying to develop strong net yarn, and in order to increase the catch, we have to consider other factors. He did not realize that there was a cause. That is, the present inventors have conducted various studies on the structure and structure of this type of fishing net for many years, and as a result, in the conventional fishing net,
The overall specific gravity is about 1.14, and the specific gravity of seawater is 1.0.
It was discovered that there is a large difference compared with the case of 3. When such a fishing net is installed as a gill net or a twine net, the net is to be sufficiently loosened in the range from near the water surface to the seabed, but the net with high specific gravity tries to sink. Therefore, this slack portion stays near the seabed, and most of the nets in seawater have no slack. Therefore, it was found that there is no slack in the net cloth at the depth at which fish pass, which makes it difficult for fish to get tangled.

In view of the above points, the present invention makes the specific gravity of the fishing net approximate to the specific gravity of seawater so that the slack portion of the installed fishing net does not stay near the sea floor and the slack can be sufficiently exerted. The present invention aims to provide a fishing net that is flexible and can be used in seawater.

[0005]

[0006]

[0007]

The present invention has a specific gravity of 0.9.
A synthetic yarn of 1 or more and 0.985 or less is twisted only in a single direction, or a two-ply twist or a three-ply twist is formed to form a twisted yarn, and the twisted yarn is knitted into a net shape by knotting, and this knitting is performed. The gist of the fishing net is characterized in that the entire netted net is dyed and treated with a resin so that the overall specific gravity is 0.98 or more and 1.04 or less.

It is preferable that the synthetic fiber is made of high molecular weight polyethylene and has a tensile strength of at least 15 g / denier, and the monofilament thickness in the synthetic fiber is 0.5 to 5. It is preferably 0.0 denier.

[0009]

With the above structure, the specific gravity of the entire fishing net can be approximated to the specific gravity of seawater of 1.03, so that the slack part of the installed fishing net does not sink to the vicinity of the sea bottom, and Since the slack portion of the net moves according to this flow when the shavings flow, the slack portion does not stay at the upper part or the lower part of the net, and it is possible to always maintain a moderate slack as a whole. Also, synthetic fibers made of high molecular weight polyethylene, having a tensile strength of at least 15 g / denier and having a single fiber thickness of 0.5 to 5.0 denier have a relatively high strength, so It is possible to make the twisted yarns that make up the above-mentioned yarn thin, and since the single fibers are thin, it is possible to obtain sufficient flexibility. Therefore, the fish and the like can be easily entangled.

[0010]

EXAMPLES Examples of the present invention will be described below. The synthetic fiber in this example is Dyneema S manufactured by Toyobo Co., Ltd.
K60 was used. This synthetic fiber is composed of high molecular weight polyethylene having a flexible polymer chain with a weight average molecular weight of 1.9 × 10 ⁶ , has a tensile strength of 32 g / denier, and has a single fiber thickness of 1.02. It is denier. This synthetic fiber is twisted into three strands to form a 1200 denier twisted yarn. This twisted yarn is provided with a frog or a knot to form a net having a mesh size of 91 mm, which is dyed and resin-processed. Therefore, in the first embodiment, the adhesion amount of the resin having a high specific gravity by the resin processing is extremely reduced, and the overall specific gravity is set to 0.98. In the second embodiment, the adhesion of the resin having a high specific gravity is performed. The specific gravity of the whole is set to 1.02 by slightly increasing the amount so that it is slightly lower than the specific gravity of seawater. In the third example, by increasing the adhesion amount of the high specific gravity resin, The specific gravity of the whole is 1.04, which is slightly higher than the specific gravity of seawater. The synthetic fiber had a specific gravity of 0.97. Next, as a comparative example, a commercially available nylon 6 multifilament fiber was used, and this was twisted into two strands to form a 1680 denier twisted yarn, and this twisted yarn was made into a net having a mesh size of 91 mm by a frog or a knot. The fishing net dyed was used. And about the above three types of fishing nets,
A weight was attached to the lower end and a float was attached to the upper end, and each was put in seawater having a specific gravity of 1.03 and left for several minutes in a transparent water tank, and the state was observed. Further, artificially flowing seawater and observing the condition of the fishing net at that time. The observation results are shown in Table 1.

[0011]

[Table 1]

From Table 1, the first, second and third embodiments all move in the flowing direction of seawater, and are very flexible in seawater. It can be understood that there is one, and one comparative example seems to be somewhat inflexible because there is almost no change in its position even when seawater flows. Furthermore, in the first and second examples, in the unflowing seawater, most of the slack part of the fishing net floats up to near the surface of the water, but when the seawater flows, the slack near the surface of the water as described above. The parts move flexibly so that the slack parts can be evenly distributed throughout the net. And, in the third embodiment, in the non-flowing seawater, most of the slack part of the fishing net exists slightly below the center position of the net, and in this state, the effect of the slack part provided on the net is It can be easily understood that it can be exerted, and when the seawater flows, the slack portion moves without counteracting the flow, and the slack portion is further increased than in the first and second embodiments. It can be evenly distributed throughout the net. On the other hand, in the comparative example, most of the slack part of the fishing net is in a state where the bottom is sunk, and even when the seawater flows as described above, almost no movement is seen in the slack part sunk in the bottom. As a result, there is no slack in the net in the range from near the water surface to near the bottom. From the above results, in the first, second, and third embodiments, when the net is present in flowing seawater, the slack portion of the net can be evenly distributed throughout the sea, so that the net is a natural fishing net. If it is installed inside, it will be able to always maintain a flexible state in accordance with the flow of seawater, and even when the slack part tries to move upward or downward due to a slight difference in specific gravity. It was found that the slack portion does not stay locally because the slack portion moves in the seawater flow direction as the seawater flows.

Next, an experiment on whether or not the fishing net is suitable in terms of strength will be described. According to the present invention, as described above, in the experiment on specific gravity, it was found that the loosened part of the net does not stay in one place, and thus the net thus obtained has sufficient strength and other conditions as a fishing net. Since it is a question whether or not it was an experiment. The synthetic fibers used here were the same as those described above, and a net was formed from 1200 denier twisted yarn in which high-molecular-weight polyethylene synthetic fibers were triple-twisted. In addition, resin processing is applied to all of them, and the knotting method is 3
Different types are used. The fourth example is a frog or a knot, the fifth example is a double frog or a knot, the sixth example is a multiple knot, and in the sixth example, the adhesion amount of the high specific gravity resin is Three types of different specific gravity were prepared for the whole net. Further, as a comparative example, the same commercially available nylon 6 multifilament fiber as described above was used, and a 1680 denier twisted yarn was used as a normal fishing net with a frog or a knot. The experimental results are shown in Table 2.

The tensile strength and the tensile strength of each net are measured according to JIS-L1013.7.5.2, and the hooking strength is measured according to JI.
According to the method specified in S-L1043 ・ 6 ・ 11.2 ・ (2).

[0015]

[Table 2]

From Table 2, the twisted yarn using the synthetic fiber made of high molecular weight polyethylene has a tensile strength of about 3.5 of the comparative example.
The value is twice that of the comparative example, and it can be seen that the one thinner than the comparative example has sufficient strength. By the way, in the fourth, fifth and sixth examples, 3 synthetic fibers made of high molecular weight polyethylene were used.
The twisted yarn made into a child twist is 1200 denier, and the tensile strength of this twisted yarn is twice or more that of the comparative example.
Synthetic fibers made of high-molecular-weight polyethylene are more slippery than nylon, and therefore, in the frog or the knot commonly used as in the fourth embodiment, the deviation of the knot is noticeable. Therefore, although the catching strength of the net was not measured, it may be inferior to that of the comparative example. However, it can be seen that if the misalignment of meshes is sequentially taken care of, it will be a good quality fishing net that can increase the catch. This also applies to the case of knitting with a double frog or knot as shown in the fifth embodiment. Therefore, by knitting with multiple knots, a fishing net with knot strength can be obtained from the fishing net of the comparative example, and the tensile strength of the net is about twice that of the comparative example. It was found that the deviation was not different from that of the comparative example. Furthermore, regarding the catch, 3
The average of the months was shown as a comparative example, but in any of the fourth, fifth, and sixth examples, any of the three types having different specific gravities among the sixth examples was used. It is easy to understand that even in the case of the comparative example, the fishing net is much larger than that of the comparative example, and that the fishing net has a good quality.

It is needless to say that various embodiments can be taken without departing from the spirit of the present invention. For example, the resin processing may be one that has been conventionally adopted, but a resin processing different from this may be applied, and the twisted yarn is made of a triple twisted synthetic fiber, As a matter of course, it is possible to employ a twisted yarn having a double twist or a twisted yarn twisted only in a single direction.

[0018]

[0019]

[0020]

As described above, the present invention has a specific gravity of 0.9.
A synthetic yarn of 1 or more and 0.985 or less is twisted only in a single direction, or a two-ply twist or a three-ply twist is formed to form a twisted yarn, and the twisted yarn is knitted into a net shape by knotting, and this knitting is performed. As the gist of the fishing net, which is characterized by dyeing the entire netted net and subjecting it to resin processing, the overall specific gravity is 0.98 or more and 1.04 or less. Is close to the specific gravity of seawater, and does not extremely rise or sink in seawater. That is, when the fishing net is installed in the seawater in a state of having slack, the slack portion does not concentrate upward or downward, in other words, can exist in a uniform state. In addition, due to tidal currents, the slack part of the fishing net is moved in the flowing direction in the constantly flowing natural sea, so even when the slack part tries to ascend or sink, its swelling or subsidence is prevented. It will be. This is a big difference from the conventional fishing net using nylon, which has a high specific gravity and is not affected by the tidal current.

Further, in the present invention, the synthetic fiber is made of high molecular weight polyethylene and is at least 15 g /
By using a synthetic fiber having a denier tensile strength and a single fiber thickness of 0.5 to 5.0 denier, the twisted yarn can be made thin and soft and tough. Ideal for fishing nets for gill nets or twine nets.

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Toshiki Tanaka 2-8-8 Dojimahama, Kita-ku, Osaka Toyo Spinning Co., Ltd. (72) Takayuki Matsui 2-8 Dojimahama, Kita-ku, Osaka Toyo Spinning Co., Ltd. (56) Reference JP-A-1-260047 (JP, A) JP-A-57-183416 (JP, A) JP-A-57-39726 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) A01K 75/00 D04G 1/00

Claims (3)

(57) [Claims] 1. A specific gravity of 0.91 or more and 0.98.
A synthetic yarn of 5 or less is twisted only in a single direction, or a two-ply or a three-ply is twisted to form a twisted yarn, and the twisted yarn is knitted into a net shape by knotting, and the entire knitted net is dyed. In addition, resin processing is applied to make the overall specific gravity 0.98.
Above, and 1.04 or less fishing net characterized by. The method according to claim 2, wherein said synthetic fibers consist high molecular weight polyethylene, at least 15 grams / denier tension fishing net according to claim 1 Symbol placement and synthetic fibers having a strength. 3. The fishing net according to claim 2, wherein the monofilament has a thickness of 0.5 to 5.0 denier.