JPH01253200A - Electric screen generation method - Google Patents

Abstract

PURPOSE:To obtain an electric screen of a strong electric field by applying only a small voltage between electrodes by applying different potentials to a pair of electrodes provided in parallel in water to form an electric field, and mixing air bubbles between the electrodes. CONSTITUTION:Three vertical conductive rods 6 are disposed at a constant interval in the direction of water passage in a water passage 5. The conductive rods 6 are connected with a row of electrodes 7, and a pair of electrode rows 7, 7 are disposed in parallel facing each other at positions adjacent to banks 4 on both sides of the water passage 5. Different potentials are applied by a DC power source 8 to the electrode rows 7, 7 to form an electric field between them. Two air pipes 10 having a number of air holes 9 are disposed at the bottom in water in the water passage 5 to cross the water passage. Air is sent to the pipes 10 by an air compressor 11, and air bubbles are produced from the air holes 9. The strength of the electric field in water is thus increased, and pass of fishes can be prevented securely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for generating an electric screen for regulating the swimming of fish and shellfish in water.

[Conventional technology]

Conventionally, when generating this type of electric screen, a plurality of conductive rods in the vertical direction are arranged at equal intervals, and the conductive rods are electrically connected to form electrodes in a groove. A plurality of electrodes are arranged parallel to each other in water, and different potentials are applied to each electrode.

Therefore, an electric field having an electric field strength based on the potential difference, that is, an electric screen is formed between each electrode in the water.

When fish and shellfish try to enter such an electric screen, they receive electrical stimulation and take repellent behavior, unable to pass through the electric screen, making it possible to block the fish and shellfish from swimming. .

[Problem to be solved by the invention]

By the way, when the electric screen described above is put into practical use, it is desirable to form something that does not interfere with ship navigation or something that is more like an intangible barrier. It is necessary to increase the size or reduce the number of conductive rods that make up the electrode.

However, when the spacing between the electrodes is increased and the number of conductive rods is decreased, the electric field intensity near the center of the formed electric field becomes weaker than in other parts of the electric field due to the concentration of the electric field near the electrodes (isoelectric rods). There is an inconvenience.

Figure 3 shows a pair of rod-shaped electrodes (1), (
1) shows the equipotential distribution when different potentials are applied by the DC power supply (2), which is the power supply voltage Vp, and the characteristics of the potential V and the electric field strength E on the A-A line.

As is clear from the figure, the picture electrode (1), (IJ
Since electric field concentration occurs near each of the picture electrodes (υ).

(The electric field strength E near the center of the gap is much weaker than the surrounding area.

As a result, when seafood swims near the center between the picture electrodes (υ, (1), the electric shock stimulation is weak, so it easily passes through the electric screen.

Here, in order to reliably block the swimming of fish and shellfish, it is conceivable to increase the voltage applied between the picture electrodes (υ, (1) to increase the electric field strength near the center, but in this case, the power source (
2) becomes larger and more expensive.

The present invention has been made in consideration of such problems of the conventional technology, and has the following objectives:
The present invention aims to provide a method for generating an electric screen that can reliably block the swimming of seafood even when the distance between a pair of electrodes is large and the voltage applied between both electrodes is relatively low.

[Means to solve the problem]

The electric screen generating method of the present invention for achieving the above object will be explained with reference to FIG.
) to form an electric field between the picture electrodes (1) and the picture electrodes (1).

(1) Air bubbles (3), . . . are mixed in between to generate an electric screen for regulating the swimming of seafood.

[Effect]

Then, when air bubbles (3),... are mixed into the electric field between the picture electrodes +1) and (17) in water, the air bubbles (3),...
・Since it itself is an insulator, air bubbles (3), ・
The potential is concentrated around the bubbles (3),..., and the slope of the underwater potential V between the bubbles (3),... becomes larger than when the bubbles (3),... do not exist, and the gradient of the underwater potential V between the bubbles (3),... The electric field strength E in the water between the bubbles (3).

It will be much stronger than if ... did not exist.

Therefore, when seafood tries to pass near the center between the image electrodes (1), (1), the electric shock is weak when there are no air bubbles (3), etc., and those that can easily pass through. At the same or lower applied voltage, air bubbles (
If 3),... are mixed in, the fish and shellfish will receive strong electrical stimulation between the bubbles (3), and even if this occurs in a part of the seafood, the fish will take repellent behavior. , will not be able to pass through electrical screens.

〔Example〕

Next, an embodiment of the present invention will be described using FIG. 2.

This embodiment is suitable for constructing a fishing pond facility in the sea, lake, river, etc., for example.
) An electric screen is formed on the water passage (5) provided in the pipe.

Three vertical conductive rods (6) are arranged at equal intervals in the direction of the water passage (5) (fish, classification blocking direction), and each conductive rod (6) is electrically connected to form an electrode. A pair of electrode rows (7) are arranged adjacent to the jetty (4) on both sides of the water passageway (5), and both electrode rows (7) are arranged adjacent to the jetty (4) on both sides of the water passage (5).
7) I (7) are parallel and opposite to each other.

Both electrode rows (7) and (7) are connected to a DC power supply (8
), different potentials are applied to both electrode rows (7),
(7) An electric field is formed between them.

At the underwater bottom of the water passageway (5), two air vibrators αQ, each of which has a large number of air holes (9) and are elongated in a direction perpendicular to the water flow direction, are disposed.

Each of these air vibes αQ has one end sealed and the other end communicated with the air compressor αη via an air tank (2) and an air hose (to).
The air sent from the air vibrator α0 is ejected from each air hole (9) of both air vibrators α0, and air bubbles (
14) ,... will be mixed in, forming an electric screen for regulating the swimming of seafood.

Therefore, even if the distance between both electrode rows (7) e (7) is increased and the voltage applied between both electrode rows (7) and (7) is relatively small, the bubbles α→,... The contaminated electric screen will reliably block the passage of fish and shellfish into the waterway.

Moreover, since air bubbles, etc. are continuously supplied to the water passageway (5), a visual threatening effect can be expected, and the swimming regulation of fish and shellfish can be effectively implemented.

In the above embodiment, if the air holes (9) in the air vibrator 0Q are arranged densely at the center and sparsely spaced toward both sides, the electric field strength between the picture electrode arrays (7) is weak near the center. More air bubbles (14), .

〔Effect of the invention〕

As explained above, according to the electric screen generation method of the present invention, since the electric screen is generated by mixing air bubbles into the electric field formed between the pair of electrodes in water, the electric field strength between the air bubbles in water is can be made stronger, and the pair l! ! Even if the distance between the electrodes is large and the voltage applied between the pair of electrodes is relatively small, an electric screen with a strong electric field strength can be obtained, which can reliably block swimming fish and shellfish, and can also be visually threatened by air bubbles. The effects are also promising.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the equipotential distribution, underwater potential characteristics, and electric field strength characteristics of an electric screen formed by the electric screen generation method of the present invention, FIG. 2 is a perspective view of one embodiment of the present invention, and FIG. This figure is an explanatory view corresponding to FIG. 1 of the electric screen formed by the conventional electric screen generation method. (1)...electrode, (3), (H)...bubble, (
7)...electrode row.

Claims (1)

[Claims] (1) Applying different potentials to a pair of electrodes arranged in parallel in water to form an electric field between the two electrodes, and mixing air bubbles between the two electrodes to generate electricity for regulating the swimming of seafood. An electric screen generation method characterized by generating a screen.