JPH0143010Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> This invention relates to a fixed net fence with high efficiency in guiding fish schools.

<Conventional technology and its problems> Fixed nets, which are generally composed of fence nets, corral nets, climbing nets, and box nets, are stretched from the water surface to the seabed, extending almost at right angles to the coastline, and are used for fishing around the coast. This system has the effect of blocking the swimming path of schools of fish by threatening them, and guiding them into the enclosure net installed at the tip of the net in the offshore direction. Therefore, as a result of ecological experiments on fish schools, it has been found that the following conditions are desirable, since the conditions that the fence net must have are such that the school of fish can perceive the net as an obstacle to the swimming path. That is, a: The color should be bright such as yellow or orange; b: The diffused reflection of light rays should be large; c: In order to increase the projected area and increase the diffused reflection, a flat or elliptical cross section is desirable; d. ; the net legs themselves emit light; e; the mesh is large enough to be a source of abnormal water pressure, sound pressure, and vibration; f; the net maintains its normal shape even when the net is blown by the tide. Therefore, the specific gravity is large.

When this is put into practical use, it is thought that these factors should be combined and determined in consideration of the difficulty of the manufacturing process and the cost. Also, among the fish schools, sardines, bonito, salmon, yellowtail, etc. migrate in the upper layer, while flounder, flounder, sea bream, squid, etc. migrate in the bottom layer, so it is necessary to take appropriate intimidation actions for each group.

On the other hand, for example, Japanese Patent Application Laid-Open No. 59-48032 or 58
-There are fixed nets as shown in Publication No. 116619, but the ones shown in these publications are
A net or rope is separately attached to the fence main body, and the net or rope is configured to swing while contacting the fence main body. Therefore, although these nets or ropes have some intimidating effect on schools of fish, the nets or ropes described in the above publication are
They were not originally installed to intimidate fish schools, but were intended to prevent seaweed from adhering to the net itself, or to remove seaweed that had adhered to it. . However, since it cannot be denied that these nets or ropes sway under the influence of tidal currents while in use, it is acknowledged that they have a threatening effect, but the entire structure including the drawings in the above publication cannot be denied. As you can see from the description, in the case of a net, the size is almost equal to the total area of the fence net itself, so if this net sways, it will sway in almost the same state as the fence net itself. When you look at it, it turns out that there is not much difference in appearance compared to the case where there is only a fence. In other words, the intimidation effect caused by the existence of this net is not that great. Furthermore, even when ropes are attached, the number of these ropes is small and their density relative to the total area of the net is small, so they are not noticeable against schools of fish, and therefore do not have much of an effective threatening effect. It was hot because I couldn't expect it.

<Means for solving the problem> Therefore, in order to solve the above-mentioned problems, the fixed net fence according to this invention uses a plurality of threatening bodies made of nets or ropes, etc., and uses a part of it to at least cover the main body of the fence. It is connected to one side, and by connecting in this way, the threatening body covers at least the entire surface of the fence main body, and the other parts of the threatening body that are not connected to the fence main body exhibit a swinging state. and
This threatening body has independence from the main body,
It sways as if it were a flying flag, and is designed to have a noticeable intimidating effect on the school of fish and to guide them.

<Example> Next, an example of the fixed net fence according to this invention will be described based on the drawings. 1 is a known fence main body, and 2 is a threatening body. This intimidation body 2 may be constructed of a net as shown in Figure 2A (hereinafter also referred to as the first example), but it may also be constructed with parallel ropes arranged vertically as shown in Figure 2B. , those arranged so that these upper and lower ropes are connected by multiple parallel ropes (hereinafter also referred to as the second example), and those formed in the shape of a rope as shown in Figure C (hereinafter referred to as the third example).
Sometimes it's an example. ) is also available. In any of these cases, the threat body 2 may be given a different color from the fence net body 1, or made of a material with the same specific gravity as seawater, or the legs of the net that constitute the threat body 2, or the rope. The cross section may be configured to be flat or elliptical, and when the threatening body 2 is constructed of a net, the mesh may have a shape different from that of the fence main body 1. For example, when the fence main body 1 is formed in a diamond pattern, the threatening body 2 is formed in a square pattern, and vice versa. Furthermore, if the cross section of the rope used in the second and third examples is formed into a so-called irregular shape, such as a cross, a flattened shape, or a triangular shape, the rope may cause abnormal water pressure, sound pressure, and vibration. It has the effect that it can be a source of such things.

In addition, in the first and second examples above, the threatening body 2
When disposing the intimidation body 2 on the fence net body 1, as shown in Fig. 3, the upper end of the menacing body 2 is connected to the fence net 1 so that it comes into close contact with the fence net 1, and the lower end is connected via a rope so that it does not come into close contact with the fence net 1. or vice versa, and furthermore, both the upper and lower ends of the menacing body 2 may be connected via a rope without being brought into close contact with each other. Further, the intimidation body 2 may be attached to one side of the fence main body 1 as shown in FIGS. 3A to 3C, but it may also be attached to both sides as shown in FIG. 3D. Furthermore, according to the results of the experiment, there was some effect when the intimidation body 2 was made the same size as the fence net body 1 and connected to the fence net body 1, but as shown in Fig. 3, Rather, it is better to make the net small and attach multiple of them, so that the movement in the seawater is large, and the resistance of the net due to the current does not become too large. It is also preferable from the viewpoint of manufacturing, as it can be freely installed.

<Effects of the invention> As mentioned above, according to the fixed net fence according to this invention, a plurality of threatening bodies made of nets, ropes, etc. are connected to at least one side of the main body of the fence,
By connecting in this way, the intimidation body covers at least the entire surface of the fence main body, and the other parts of the threat body that are not connected to the fence main body exhibit a swinging state. This menacing body becomes independent from the main body of the fence and sways as if it were a flag, and the presence of the menacing body increases the diffuse reflection of the light beam, increasing the projected area and causing abnormalities. It generates strong water pressure, sound pressure, and vibration, and has the effect of intimidating schools of fish and increasing the efficiency of guiding them.

[Brief explanation of the drawing]

The drawings show one embodiment of the fixed net fencing according to this invention. Fig. 1 is a perspective view, Fig. 2 (a) is a perspective view of the threatening body formed of a net, and Fig. 2 (b) is a perspective view of the threatening body formed of the net. Figures 3A, 3B, 3C, and 3 are perspective views of the intimidation body formed in the form of a rope; Figure 3C is a perspective view of the threat body formed in the shape of a rope; It is a side view which shows a state. 1...The fence body, 2...The threatening body.

Claims (1)

[Scope of utility model registration request] A plurality of intimidation bodies composed of nets, ropes, etc. are connected to at least one side of the fence main body by a part thereof, and by being connected in this way, the intimidation bodies cover at least the entire surface of the fence net main body, and A fixed net fence characterized in that the other part of the threatening body that is not connected to the fence main body exhibits a swinging state.