JPS62278797A - Apparatus for prohibiting swimming of fish and shells - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] This invention provides a method for blocking the swimming of fish and shellfish in seawater when culturing fish and shellfish. Regarding equipment.

[Conventional technology]

Traditionally, when cultivating fish and shellfish, a net is stretched around the seawater to form a cage, and two people are placed inside the cage to farm the fish, but the nets used to form the cages are easily damaged, so it is difficult to preserve the nets. This requires a great deal of effort and expense, and proposes a device as shown in FIG.

First, in Fig. 7, (1) is six conductive electrodes (21 is an AC power supply for generating an electric screen, and is connected to one end of the power supply +21 m (
3a), one B electrode (I+) is connected to the other end of the power supply +21 through another connection line (3b), and the remaining electrodes [11 are connected to each other by the power supply 121. Voltages are applied such that the polarity of the electrodes (1) is different, and an electric screen is formed between each electrode (1), so that the inner part of each electrode (1) is formed by the screen.

Swimming of fish and shellfish to the outside is blocked.

At this time, for example, if the distance between two adjacent electrodes fl1 is L, then 2
The distribution of electric field strength at both electrodes (l
) The electric field strength at positions close to both electrodes fl+ is extremely high, and the electric field strength becomes almost constant at a certain distance from both electrodes fl+. However, the horizontal axis in FIG. 8 is one electrode f
When the center of i+ is taken as a reference.

The distance to the center of the other electrode (1) is shown.

Next, in FIG. 9, (4a) is a first electrode row, in which a plurality of vertically long conductive electrodes (5a) with a circular cross section are arranged at intervals L' in seawater. The electrodes (5a) are electrically connected to each other by a connecting body to form a first electrode row (4a).

(4b) is a second electrode row, in which, like the first electrode row (4a), a plurality of vertically long conductive electrodes (5b) with a circular cross section are arranged at intervals L' in seawater. , each electrode (5b) is electrically connected to each other by a connecting body to form a second electrode row (4b), and both electrode rows (4a).

(4b) are arranged in parallel.

(6) connects both electrode rows (4a) at both ends or via the above-mentioned both connectors.
.

(4b) is an AC power source for generating an electric screen, and the power source (6) is connected to both electrode arrays (4a), (4
b) An alternating current voltage is applied between both electrode rows (4a), (
4b) An electric screen is formed in between, and the screen blocks fish and shellfish from swimming.

At this time, the distribution of isoelectric lines obtained by connecting two equipotential points on the cross section perpendicular to each electrode (5a) and (5b) is as shown in the dashed line in FIG. Electrode row (
4a), (4b) electrodes (5a), (5b).
The distribution of the electric field strength is as shown in FIG. 10, and the electric field strength at positions close to both electrodes (5a) is very high, and at a position intermediate between both electrodes (5a), it is almost 0. However, the horizontal axis in FIG. 10 indicates the distance from the center of one electrode (5a) to the center of the other electrode (5a).

[Problem that the invention seeks to solve]

By the way, as mentioned above, when cultivating fish and shellfish by using the inside of each electrode il+ in Figure 7 as a cage, as shown in the figure, the cultured fish CF+ approaches one of the electrodes il+ as indicated by the arrow in the figure. Then, due to the high electric field strength near the electrode III, the fish () may receive strong electrical stimulation and become paralyzed or even die. There is a problem.

Therefore, it is conceivable to apply a voltage to the extent that the farmed fish and shellfish will not receive strong electrical stimulation even if they approach the electrode (1), but in this case, the adjacent electrode (1)
) The electric field strength at the intermediate position becomes too low, causing the inconvenience that it no longer functions as an electric screen, so the above-mentioned problem cannot be solved by adjusting the application arm of the power supply (2).

In addition, both electrode rows (4a) and (4b) in FIG.
For example, when the first electrode row (4a) 'e is placed inside so as to surround a specific area, and when fish and shellfish are cultured using the specific area as a cage, both electrodes are placed on the inside as shown by the arrows in the figure. Fish (
When the moon approaches, due to the high electric field strength near the electrode (5a), the cultured fish and shellfish are damaged by the electric stimulation when they are in the cage due to strong electric stimulation before entering the electric field screen. There is a problem with receiving it.

Therefore, the technical object of this invention is to prevent damage to cultured fish and shellfish caused by electrical stimulation in areas other than the electric screen within the cage, without impairing the function of the electric screen.

[Means for Solving the Problems] The present invention has been made with the above-mentioned points in mind, and consists of arranging a plurality of elongated conductive electrodes at approximately equal intervals in the vertical direction in seawater to generate electricity. A voltage is applied to each of the electrodes by a screen generation power source to generate an electric screen between the electrodes, and a cross section of each electrode is placed in a fish and shellfish swimming blocking device that blocks swimming of fish and shellfish. , a fish and shellfish swimming blocking device characterized by having a shape having two or more types of radii of curvature. - [Operation] According to the present invention, a plurality of vertically elongated conductive electrodes each having a cross section with two or more different radii of curvature are arranged in seawater, and a power source for generating an electric screen is provided. A voltage is applied to each conductive electrode to form an electrical screen between each electrode.

At this time, since the cross section of the conductive electrode was shaped to have two or more radii of curvature, the electric field strength near the electrode due to voltage application is higher near the electrode surface with a larger radius of curvature than near the electrode surface with a smaller radius of curvature. By appropriately arranging electrode surfaces that are small and have a large radius of curvature on desired sides, fish and shellfish in areas other than the electric screen can receive strong electrical stimulation without impairing the swimming-blocking function of the electric screen. Damage is prevented.

〔Example〕

Next, the present invention will be explained in detail with reference to FIGS. 1 to 6 showing embodiments thereof.

(First Example) First, FIGS. 1 to 3 showing the first example will be described.

2 in FIG. 1, the same symbols as in FIG. 7 indicate the same things, and the difference from FIG. 7 is that the cross section is 2
The conductive electrode (7) is elongated in the vertical direction in an oblong shape having a different radius of curvature, and is arranged with the electrode surface having a large radius of curvature facing inside, that is, on the cage side.

At this time, for example, the solid line and the dashed-dotted line in FIG.

As shown by the two-dot chain line, the radius of curvature of the opposing electrode surfaces of two adjacent electrodes (7) is R1, R2, R3 (
R1<R2<R3), and if the distance between both electrodes (7) is L as in the case of FIG.
) and the electric field strength in the vertical cross section.

The distributions are shown in Figure 3 (al and (bl), respectively, and the solid lines, one-dot chain lines, and two-dot chain lines in each square correspond to the electrode surfaces with radii of curvature R1, R2, and R3 in Figure 2, respectively. The horizontal axis of Figure 3 (al, [bl] indicates the distance to the center of the other electrode (7) with the center of one electrode (7) as the reference, FIG. 3 (al represents the potential of the other electrode (7) as a reference).

As can be seen by comparing the solid line and the two-dot chain line in Figure 3-e (al, (b)), the larger the radius of curvature of the electrode surface, the more the potential gradient becomes constant at all points, and the electric field strength increases. becomes uniform, and the electric field strength near the electrode decreases as the radius of curvature increases.

Therefore, as shown in Fig. 1, by arranging the electrode (7) with an oval cross section with the electrode surface with a large radius of curvature facing the cage side, it is possible to Even if you approach the electrode (7) as shown by the arrow, the fish (F″I is the electrode (7)
The electrical stimulation received by the fish in the vicinity of the fish is greatly reduced compared to the case shown in FIG.

By the way, between each electrode (7), the radius of curvature of the opposing surface of each electrode (7) is smaller than that of the cage side, and is about the same as in the case of Fig. 7 described above. The generated electric screen's ability to block the swimming of fish and shellfish will not be impaired.

(Second Embodiment) Next, FIGS. 4 to 6 showing a second embodiment will be described.

In Fig. 4, the same symbols as in Fig. 9 indicate all the same parts, and the difference from Fig. 9 is that the electrodes (5a) and (5b) each have two different radii of curvature in the cross section. The third conductive electrode (8a), (8b) is elongated in the vertical direction of the oval shape. A fourth electrode row (9a), (9b) is constructed, and both electrode rows (9a), (9b) and the top electrode (8a), (
8b) The electrodes (8a) and (8b) are arranged so that the radius of curvature of each opposing surface is large, and this is the runner-up. Na2
, in Figure 4.

At this time, as shown by the solid line, one-dot chain line, and two-dot chain line in FIG. R
,1', R2', R,3'(R1'<R2'
<R,3'), and if the distance between both electrodes (8a) is L' as in the case of FIG. The electric field strength distributions are shown in Figure 6 (al, (bl), respectively, and the solid lines, dashed-dot lines, and dashed-double lines in each figure represent the radii of curvature R1', R2', and R in Figure 5, respectively. ，
It corresponds to the 3' electrode voltage. However, Fig. 6(a),
(The horizontal axis of bl indicates the distance from the center of one electrode (8a) to the center of the other electrode (8a).

As can be seen by comparing the solid line and the two-dot chain line in FIG. As a result, the electric field strength is low, almost 0, and 2 near the electrode.
The electric field strength decreases as the radius of curvature increases.

Therefore, as shown in FIG. 4, each electrode (8a), (8b
), and if a fish tank is formed by surrounding a specific area with the third electrode row (9a) inside, for example, both electrode rows (9a ),
Even if the fish approaches the electric screen between electrodes (9b), the electrical stimulation received by the fish near the electrode (8a) will be greatly reduced compared to the case shown in Figure 9. (B is prevented from being damaged by electrical stimulation before it enters the electrical screen.

By the way, between both electrode rows (9a) and (9b), the radius of curvature of the opposing surfaces of each electrode (8a) and (8b) is smaller than that on the cage side, and is about the same as in the case of FIG. 9 described above. , the function of blocking the swimming of fish and shellfish of the electric screen generated between both electrode rows (9a) and (9b) is not impaired.

2. Of course, the cross-sectional shape of the conductive electrodes (71, (8a), (8b) is not limited to the above-described oval shape.

〔Effect of the invention〕

As described above, according to the fish and shellfish swimming blocking device of the present invention, the cross section of the conductive electrode is set in a shape having two or more radii of curvature. The area near the electrode surface with a larger radius of curvature is smaller than the area near the electrode surface, and by appropriately arranging the electrode surface with a large radius of curvature on the desired side surface, it is possible to prevent the electric screen from impinging on water without impairing the swimming-blocking function of the electric screen. This method is extremely effective in preventing fish and shellfish in this region from being damaged by strong electrical stimulation.

[Brief explanation of the drawing]

1 to 6 show all the embodiments of the fish and shellfish swimming blocking device of the present invention, FIG. 1 is a cutaway plan view of the first embodiment, and FIGS. 2 and 3 are the principles of FIG. 1. FIG. 2 is a schematic diagram, FIG. 3 (al, (bl) is a potential distribution diagram 2 and an electric field strength distribution diagram, respectively, FIG. 4 is a cutaway plan view of the second embodiment, and FIG. 6, FIG. 7, 3 and 9 are cut-away plan views of a fish and shellfish swimming cutoff device compared with the present invention, FIG. It is an electric field strength distribution diagram at 2. +21, +61... Denryu, (7), (8a)
, (8b) , -, 4-electrode. Agent Patent Attorney Fuji 1) Ryutabe No. 1ri! J Fig. 2 (a) Fig. (b) Fig. 4 Fig. 5 (cL) Fig. Cb) Fig. 7 Fig. 8゛Distance---

Claims (1)

[Claims] (1) A plurality of long conductive electrodes are arranged vertically in seawater at approximately equal intervals, and a voltage is applied to each of the electrodes by a power source for generating an electric screen to generate an electric screen between the electrodes. A fish and shellfish swimming blocking device for blocking swimming of fish and shellfish, characterized in that the cross section of each of the electrodes has a shape having two or more types of curvature radii.