JPH0442789B2 - - 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 in the early stage of aquaculture, farmed fish are still young fish with a body length of several centimeters, and in order to block 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, the nets are easily damaged, and even if the damage is slight, young fish can easily escape, requiring a great deal of effort and expense to maintain the nets. This will cause inconvenience.

[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]

This invention has been made with the above points in mind, and includes a plurality of electrodes arranged at approximately equal intervals in seawater, and a first electrode electrically connected to every other electrode. A connecting body, a second connecting body electrically connected to each of the remaining electrodes, and a power source for generating an electric screen that applies a DC voltage, an AC voltage, or a pulse voltage between both the connecting bodies. This is an electric screen generator featuring:

[Effect]

In this invention, among the plurality of electrodes arranged in seawater, the first connecting body is electrically connected to every other electrode, and the second connecting body is connected to each of the remaining electrodes. They are electrically connected, and a DC voltage, AC voltage, or pulse voltage is applied between both connected bodies by a power source for generating an electric screen, and an electric screen is formed between each electrode in seawater to prevent fish from entering the electric screen. Shellfish exhibit reactions such as mild numbness or paralysis when receiving electrical stimulation, and are unable to swim through the electrical screen.
The swimming of fish and shellfish is reliably blocked without using nets as in the past, and it is not affected by ocean conditions such as tide level, tide, water depth, or weather conditions such as typhoons, making it suitable for large-scale aquaculture such as on marine farms. very suitable for

〔Example〕

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

First, FIGS. 1 to 4 showing one embodiment will be explained.

In FIG. 1 showing a schematic configuration, 1 is a plurality of rod-shaped or tubular electrodes arranged vertically in a straight line at approximately equal intervals in seawater, and 2 is an electrical connection to every other electrode 1. 3 is a connected first connecting body; 3 is a second connecting body electrically connected to each of the remaining electrodes 1;
Reference numerals 4 and 5 denote connecting terminals provided on both the connecting bodies 2 and 3, respectively, and an output terminal of a power source for generating an electric screen (not shown) is connected to both the connecting terminals 4 and 5. A DC voltage, an AC voltage, or a pulsed voltage is applied between the electrodes 1 and 3 to form an electric screen in the area including each electrode 1.

At this time, for example, when a voltage is applied so that the first connection body 2 side has a high potential, a line obtained by connecting equipotential points in an arbitrary horizontal section perpendicular to each electrode 1, that is, an equipotential line is as shown in FIG. 2, and A- passing through each electrode 1 in FIG.
The distribution of the potential V and the electric field strength |E| on the A' line is as shown in Figure 3 a and b, respectively. As shown in Figure 3 b, the electric field strength between each electrode 1 is almost constant, and similarly The distributions of the potential V and the electric field strength |E| on the line B-B', which is slightly shifted from the line A-A' in Figure 2, are as shown in Figure 4 a and b, respectively, and as shown in b of the same figure, Compared to the case in FIG. 3a, the range in which the electric field strength is constant is narrower.

However, in FIGS. 3a and 3b and FIGS. 4a and 4b, the horizontal axis is the distance from the leftmost electrode 1 to each electrode 1, and the interval between each electrode 1 is 1.

Therefore, it is said that swimming of fish and shellfish can be suppressed if the electric field strength is 0.01 V/cm or more, so the electric field strength in a desired area centered on each electrode 1 should be set to the above value. By controlling the distance between each electrode 1 and the applied voltage, fish and shellfish that invade the electric screen formed in the area including each electrode 1 will be unable to swim through the electric screen, and each electrode 1 will If the electrodes 1 are arranged to surround the area, fish and shellfish will be confined within the area surrounded by the electrodes 1.

Next, FIGS. 5 and 6 show other embodiments.
The diagram will be explained.

In FIG. 5, the same symbols as in FIG. 1 indicate the same things, and the difference from FIG. 1 is that a flat electrode 6 is used instead of the rod-shaped or tubular electrode 1. As in the case shown in the figure, equipotential lines when a voltage is applied by the power source described above become as shown in FIG. 5, for example.

At this time, when a voltage is applied so that the first connection body 2 side has a high potential, each electrode 6 in FIG.
The distribution of the potential V and the electric field strength |E| on the C-C' line passing through the center of is as shown in FIG. 6a and b, respectively, and as shown in FIG. | becomes constant.

As shown in FIG. 7, for example, three rod-shaped or tubular electrode bodies 7 are connected to form one electrode 8, and a plurality of these electrodes 8 are arranged at approximately equal intervals in seawater. may be set.

Furthermore, it goes without saying that each of the electrodes 1, 6, and 8 may be arranged in a predetermined curved shape.

Furthermore, the electrodes 1, 6, and 8 are not limited to those described above.

〔Effect of the invention〕

As described above, according to the electric screen generator of the present invention, a plurality of electrodes 1, 6, 8 are placed in seawater.
The first connecting body 2 is connected to every other electrode 1, 6, 8, and the remaining electrodes 1, 8 are connected to each other.
A second connecting body 3 is connected to the terminals 6 and 8, and a voltage is applied between the connecting bodies 2 and 3 using a power source for generating an electric screen to generate an electric screen. It is possible to prevent fish and shellfish from passing by by applying a target stimulus, and unlike when using conventional nets, fish and shellfish can be reliably caught without being affected by ocean conditions such as tide level, tide, water depth, etc., or weather conditions such as typhoons. This makes it possible to cut off the swimming of fish, reducing the labor and cost required for maintaining the nets, making it extremely effective for large-scale aquaculture such as on marine farms, and its effects are extremely large.

[Brief explanation of drawings]

The drawings show an embodiment of the electric screen generator of the present invention, and FIGS. 1 to 4 show one embodiment, FIG. 1 is a schematic diagram, FIG. 2 is an explanatory diagram of operation, and FIGS. Figure 4 shows the potential and electric field strength distribution at different positions of the electric screen, each figure a is a potential distribution diagram, each figure b is an electric field strength distribution diagram, and Figures 5 and 6 are other examples. shows,
FIG. 5 is an operation explanatory diagram, and FIGS. 6 a and 6 are electrical potential distribution and electric field strength distribution diagrams of the electric screen, respectively.
FIG. 7 is a schematic configuration diagram of still another embodiment. 1, 6, 8...electrode, 2, 3...first, second connection body.

Claims (1)

[Claims] 1. A plurality of electrodes arranged at approximately equal intervals in seawater, a first connecting body electrically connected to every other electrode, and a first connecting body electrically connected to the remaining electrodes. An electric screen generating device comprising: a second connecting body; and a power source for generating an electric screen that applies a DC voltage, an AC voltage, or a pulse voltage between the two connecting bodies.