JPH0442790B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric screen generating device for generating an electric screen for blocking the swimming of fish and shellfish in seawater when cultivating fish and shellfish.

[Conventional technology]

Generally, when cultivating fish and shellfish, a cage is set up in seawater, and the fish and shellfish are cultured within the cage.Usually, a net is stretched around the seawater to form a cage, and the net is used to extend the fish and shellfish to the outside of the cage. This method prevents fish and shellfish from escaping and entering the inside of the cage, but at the early stage of aquaculture, farmed fish are still young fish with a body length of several centimeters, and in order to prevent the swimming of these young fish, In this case, it is necessary to use a very fine-mesh net to be placed in seawater.

However, in sea areas where tidal changes can be as large as several meters, nets are easily damaged, and even if the damage is slight, young fish can easily escape, resulting in the inconvenience of requiring a great deal of effort and expense to maintain and maintain the nets. arise.

[Problem that the invention seeks to solve]

Therefore, areas where the water is not too deep, where the waves are calm, and where there are few tidal changes are usually selected as areas where fisheries are installed. However, even in areas that meet these conditions, nets may be washed away by typhoons or ships may be lost. The net may be damaged due to contact, and maintenance and upkeep of the net requires a great deal of effort and expense, and there is a problem in that the net cannot reliably block the swimming of fish and shellfish.

In addition, when carrying out large-scale aquaculture such as at marine farms, the total length of the nets used is extremely long, and the labor and expense required to maintain and maintain the nets are correspondingly large. Using nets for isolation is not the best strategy for large-scale aquaculture.

Therefore, the technical problem of this invention is to ensure that swimming of fish and shellfish can be blocked without being affected by ocean conditions such as tide levels and tides, or weather conditions such as typhoons.

[Means for solving problems]

The present invention has been made with the above-mentioned points in mind, and includes five electrode rows in which a plurality of conductive electrodes are arranged in seawater at approximately equal intervals and arranged in parallel to each other; A connection body that electrically connects the conductive electrodes of each of the electrode rows to each other, and the electrode rows on both sides and the center are at a low potential, and the remaining two rows of the electrode rows are at a high potential,
The electric screen generating device is characterized in that it includes a power source for electric screen generation that applies a voltage between each of the electrode rows.

[Effect]

In this invention, an electric screen is generated between five rows of electrodes arranged parallel to each other in seawater so that the electrodes on both sides and the center are at a low potential and the remaining two rows are at a high potential. A voltage is applied by a dedicated power supply, and a four-layer electric screen is formed between each row of electrodes in the seawater, and fish and shellfish that enter the electric screen receive electrical stimulation and exhibit reactions such as mild numbness or paralysis. It is no longer possible for fish and shellfish to swim through the electric screen, and the swimming of fish and shellfish is reliably blocked without using nets as in the past, and it is affected by ocean conditions such as tide level, tide, water depth, and weather conditions such as typhoons. It is very suitable for large-scale aquaculture such as ocean farms.

〔Example〕

Next, the present invention will be described in detail with reference to drawings showing one embodiment thereof.

First, the principle of this invention will be explained.

For example, as shown in Figure 3, five electrodes A ₁ , A ₂ , A ₃ , A ₄ , A ₅ are arranged in parallel in seawater, and the electrodes A ₁ and A ₅ on both sides and the center Electrode A ₃ is at low potential, i.e. earth potential, and the remaining electrodes A ₂ ,
A voltage is applied between each electrode _{A 1 to A 5} so that A 4 has a high potential to form a quadruple electric screen having a predetermined potential gradient.

At this time, the distance from electrode A ₁ to A ₂ is L ₁ , the distance from electrode A ₂ to A ₃ is L ₂ , the distance from electrode A ₃ to A ₄ is L ₃ , and the distance from electrode A ₄ to A ₅ is If the distance is L ₄ and the potential of electrodes A ₂ and A ₄ is V ₀ , then each electrode A ₁
The potential distribution between ~ _A5 is shown in Figure 4,
The potential gradient E ₁ between electrodes A ₁ and A ₂ is E ₁ ≒V ₀ /L ₁ , electrode
The potential gradient E ₂ between A ₂ and A ₃ is E ₂ ≒ V ₀ /L ₂ , electrode A ₃ ,
The potential gradient E ₃ between the electrodes A ₄ is E ₃ ≈V ₀ /L ₃ , and the potential gradient E ₄ between the electrodes A ₄ and A ₅ is E ₄ ≈V ₀ /L ₄ .

And if the potential gradient E ₁ - _{E 4} of the electric screen between each electrode A ₁ - _{A 5} is small, fish and shellfish will only show a surprising reaction, and as the potential gradient E ₁ - _{E 4} becomes larger, it will be lighter. It begins to show reactions such as numbness, paralysis, asphyxia, and death, and a different potential gradient
The combination of E ₁ to _{E 4} results in the formation of a four-layer electric screen that provides different degrees of electrical stimulation to fish and shellfish.

Therefore, as shown in FIG. 1, a plurality of rod-shaped conductive electrodes 1a are arranged in seawater at approximately equal intervals to form a first electrode row 2a, and a plurality of rod-shaped conductive electrodes 1a are similarly arranged in seawater at approximately equal intervals. The electrodes 1b, 1c, 1d, and 1e are arranged at approximately equal intervals to form second, third, fourth, and fifth electrodes.
Electrode rows 2b, 2c, 2d, and 2e are formed, and the electrode rows 2a to 2e are arranged so that the electrode rows 2a to 2e are parallel to each other and the intervals between the electrode rows 2a to 2e are different. , each electrode row 2a to 2e
Each conductive electrode 1a, 1b, 1c, 1d,
1e are electrically connected to each other by connecting bodies 3a, 3b, 3c, 3d, and 3e, and the first and fifth electrodes 2a and 2e on both sides and the third electrode row 2c in the center are connected as the low potential side, that is, the ground side. The first terminal 4a and the connecting body 3 connected to the bodies 3a, 3e and 3c
For example, a DC voltage is applied between the second terminal 4b connected to the electrodes 2a and 3d by a power source for generating an electric screen (not shown), and each electrode row 2a to 2
A so-called four-layer electric screen with different potential gradients is formed between the two electrodes.

At this time, if each electrode row 2a to 2e is placed in the seawater so as to surround a specific area with the electric screen, fish and shellfish can escape from the area surrounded by the electric screen and Entry of fish and shellfish into the enclosed area is reliably prevented, fish and shellfish cannot swim through the electric screen, and fish and shellfish are confined within the area surrounded by the electric screen. .

For example, each conductive electrode 1a, 1b, 1
Copper pipes with a diameter of 20 mm are used as electrodes c, 1d, and 1e, and these are arranged at 40 cm intervals to form electrode rows 2a to 1e.
2e, and the second electrode example 2 is formed from the first electrode row 2a.
b, the distance from the second electrode row 2b to the third electrode row 2c is 25 cm, the distance from the third electrode row 2c to the fourth electrode row 2b is 25 cm, and the fourth electrode row 2
When the distance from b to the fifth electrode row 2e is 75 cm and the potential of the second and fourth electrode rows 2b and 2d is 5V, the potential distribution between each electrode row 2a to 2e is as shown in FIG. The potential gradient at the intermediate position between the first and second electrode rows 2a and 2b and between the fourth and fifth electrode rows 2b and 2e is approximately 0.07 V/cm.
The potential gradient at the intermediate position between the third electrode rows 2b and 2c and between the third and fourth electrode rows 2c and 2d is approximately 0.2 V/cm, and the first
Fish and shellfish that have invaded between the second electrode rows 2a and 2b and between the fourth and fifth electrode rows 2b and 2e are startled and immediately escape.
Fish and shellfish that invaded between b and 2c and between the third and fourth electrode rows 2c and 2d showed reactions such as paralysis and asphyxia. However, the horizontal axis in FIG. 2 indicates the distance from the first electrode row 2a.

Here, when the paralyzed or asphyxic fish and shellfish come out of the electric screen, the paralyzed or asphyxic state returns to its original normal state after a while.

Note that the conductive electrodes 1a to 1e are not limited to the rod-shaped ones described above.

Furthermore, it goes without saying that an AC voltage or a pulse voltage may be applied between each of the electrode rows 2a to 2e by a power source for generating an electric screen.

〔Effect of the invention〕

As described above, according to the electric screen generating device of the present invention, the first to fifth electrode rows 2a to 2e are arranged in parallel in seawater, and the power source for electric screen generation is used to connect the electrode rows 2a to 2e. , the first on both sides,
Fifth electrode rows 2a, 2e and third electrode row 2 in the center
Applying a voltage so that c has a low potential and the remaining second and fourth electrode rows 2b and 2d have a high potential,
Since a four-layer electric screen is generated, it is possible to electrically stimulate fish and shellfish that have entered the electric screen to prevent them from swimming, and unlike when using a conventional net, it is possible to prevent fish and shellfish that have entered the electric screen from swimming through the screen. It is now possible to reliably block the swimming of fish and shellfish without being affected by ocean conditions or weather conditions such as typhoons, reducing the labor and cost required for net maintenance, and improving marine farms. It is very effective for large-scale aquaculture such as, and its effects are extremely large.

Furthermore, each electrode row 2a, 2b, 2c, 2d, 2
By appropriately adjusting each distance between electrodes 2a, 2b, 2c, 2d, and 2e, the potential gradient between each electrode array 2a, 2b, 2c, 2d, and 2e can be controlled, and the degree of electrical stimulation given to fish and shellfish can be adjusted. This makes it possible to reliably protect items without damaging them.

[Brief explanation of drawings]

The drawings show one embodiment of the electric screen generator of the present invention, in which Fig. 1 is a perspective view, Fig. 2 is a potential distribution diagram between each electrode row, Fig. 3 is a diagram explaining the principle, and Fig. 4
The figure is a potential distribution diagram between each electrode in FIG. 3. 1a, 1b, 1c, 1d, 1e...conductive electrodes,
2a, 2b, 2c, 2d, 2e... electrode row, 3
a, 3b, 3c, 3d, 3e... connection body.

Claims (1)

[Claims] 1. Five rows of electrodes formed in seawater with a plurality of conductive electrodes arranged at approximately equal intervals and arranged in parallel to each other, and the conductive electrodes of each of the electrode rows are electrically connected to each other. a connecting body,
and a power source for generating an electric screen that applies a voltage between each of the electrode rows so that the electrode rows on both sides and the center are at a low potential and the remaining two rows of the electrode rows are at a high potential. Features: Electric screen generator.