JP7481692B2 - Live fish calming system - Google Patents

Description

The present invention relates to a system that calms live fish by applying electrical stimulation to them after landing.

A method is known in the past in which live fish are given an electrical stimulus and landed in a tranquilized state (Patent Document 1). In this method, a number of fish with spines are scooped up from the sea with a landing net, and after all the fish have been taken out of the sea and into the air, electricity is passed through two electrodes installed in the landing net to pass electricity through the seawater adhering to the surface of the fish's body, and the fish are electrocuted to a degree that does not damage the spine, thus tranquilizing them.

JP 2017-18028 A

However, with the above-mentioned conventional tranquilization method, it is difficult to apply electricity uniformly to the fish scooped up in the landing net. For example, fish closest to the electrodes of the landing net may break bones due to the electrical stimulation being too strong, while fish farther from the electrodes may not be tranquilized. In addition, if another fish is in contact with the electrode, the amount of current flowing through each fish may change depending on the contact state of the contacting fish, and the effectiveness of the electrical stimulation may become uneven. Furthermore, since there is variation in the dimensions of the fish scooped up from the fish pens with the landing net, even fish that do not meet the shipping size are stimulated electrically and must be disposed of. Furthermore, small fish that are different from the fish to be processed may also be mixed in with the fish pens, increasing the workload of sorting and disposing of these small fish.

Therefore, in order to solve the above problems, the main objective of the present invention is to provide a live fish calming system that can apply uniform electrical stimulation to multiple landed fish.

To achieve the above objective, the first aspect of the present invention is a live fish tranquilizing system for tranquilizing live fish by passing an electric current through them, comprising a lattice electrode in which electrode rods of different polarities are supported in parallel, alternating with a predetermined width of space between them, and a controller for controlling the output of the electric current passed through the lattice electrode.

The second aspect of the live fish tranquilizing system according to the present invention is the first aspect described above, further comprising a tilting mechanism for tilting the grid electrode.

A third aspect of the live fish tranquilizing system according to the present invention is the second aspect described above, further comprising a casing that houses the lattice electrode and surrounds the periphery of the lattice electrode, the casing having a first opening/closing gate that can be driven to open and close, and the tilting mechanism tilts the lattice electrode so that the side of the first opening/closing gate is positioned lower.

The fourth aspect of the live fish tranquilizing system of the present invention is the third aspect described above, in which the first opening and closing gate and the tilting mechanism are configured to work together so that the side of the first opening and closing gate of the lattice electrode is positioned lower when the first opening and closing gate is open.

A fifth aspect of the live fish tranquilizing system according to the present invention is any one of the first to fourth aspects described above, further comprising a first tank that receives fish that fall through the gap of the specified width between adjacent electrode bars.

The sixth aspect of the live fish tranquilizing system of the present invention is the third aspect described above, in which the casing includes a hopper section that narrows downward to receive fish that fall from the gaps between adjacent electrode bars, and a chute section that is connected to the lower end of the hopper section and sends the fish that fall from the hopper section to a specified location.

The seventh aspect of the live fish tranquilizing system according to the present invention is any one of the first to sixth aspects described above, further comprising a retention section for temporarily retaining the live fish sent to the grid electrode.

The eighth aspect of the live fish tranquilizing system according to the present invention is the seventh aspect described above, further comprising a second opening/closing gate between the retention section and the lattice electrode, and is configured so that the second opening/closing gate is closed when the lattice electrode is energized.

A ninth aspect of the live fish tranquilizing system of the present invention is configured in the seventh or eighth aspect above, wherein the retention section includes a sorting table having gaps formed therein for allowing fish smaller than a predetermined size to fall through, and live fish that are sorted without falling through the gaps in the sorting table are sent onto the lattice electrode.
A tenth aspect of the live fish tranquilizing system according to the present invention is the above-mentioned ninth aspect, wherein the sorting table is arranged in an inclined manner so as to become lower as it approaches the grid electrode.

An eleventh aspect of the live fish tranquilizing system according to the present invention is the ninth aspect described above, further comprising a sorting table tilting mechanism that tilts the sorting table, and the sorting table tilting mechanism tilts the sorting table so that the lattice electrode side of the sorting table is positioned low.

A twelfth aspect of the live fish tranquilizing system according to the present invention is any one of the ninth to tenth aspects described above, further comprising a vibration imparting device for vibrating the sorting table to shake off live fish on the sorting table that are smaller than a predetermined size through the gaps in the sorting table.

According to the live fish sedation system of the present invention, a fish can be placed on a grid-like electrode in which electrode rods of different polarities are arranged alternately, and electricity is passed through it, causing a current to flow through the surface of the fish's body, providing electrical stimulation and seducing it. By arranging multiple fish on the grid-like electrode, each fish comes into contact with an electrode rod of a different polarity, and electrical stimulation can be uniformly provided to multiple fish placed on the grid-like electrode.

1 is a perspective view showing a first embodiment of a live fish tranquilizing system according to the present invention, with a portion cut away and a portion enlarged view; FIG. FIG. 2 is a perspective view showing the operating state of the live fish tranquilizing system of FIG. 1. FIG. 2 is a perspective view showing another operating state of the live fish tranquilizing system of FIG. 1. FIG. 2 is a perspective view showing a second embodiment of a live fish tranquilizing system according to the present invention.

An embodiment of a live fish tranquilizing system according to the present invention will be described below with reference to Figures 1 to 4. Identical or similar components are designated by the same reference numerals throughout all figures and all embodiments.

First, a first embodiment of a live fish tranquilizing system according to the present invention will be described with reference to Figures 1 to 3. The live fish tranquilizing system 1 is a system for passing an electric current through live fish to tranquilize them, and includes a lattice-shaped electrode 4 in which electrode rods 2 and 3 of different polarities are supported in parallel, alternately with a predetermined gap G1 between them, and a controller 5 that controls the output of the electric current passed through the lattice-shaped electrode 4.

In the illustrated example, the electrodes 2 and 3 are stainless steel pipes with a diameter of 18 mm, and the distance G1 between adjacent electrodes 2 and 3 is set to 25 mm. The diameter of the electrodes 2 and 3 and the distance G1 between the electrodes 2 and 3 can be set appropriately.

The electrodes 2, 3 are supported by connecting both ends to a rectangular frame 6, forming a grid-like electrode 4. The frame 6 is made of an insulating material such as hard plastic, and the positive electrode 2 and the negative electrode 3 are electrically insulated. The positive electrode 2 is connected to a common wiring 2A, and the negative electrode 3 is connected to another common wiring 3A, which is connected to the positive and negative poles of a DC power source 7 via a controller 5, as described below.

As shown in the figure, the controller 5 is connected between the DC power supply 7 and the grid electrode 4. The controller 5 can include an on/off switch and circuits for adjusting the current application time, current application voltage, and pulse waveform of the current application to control the output of the current applied to the grid electrode 4. The current application time and current application voltage (current application) must be adjusted according to the size of the target fish to be sedated. For example, in the case of a two-year-old coho salmon, the controller settings can be set to an output voltage of 35-100V, a current application of 5-20A, a pulse width of 2-10 milliseconds, and a current application time of 6-40 seconds, making it possible to sedate the coho salmon without breaking any bones or causing internal bleeding.

The grid electrode 4 is housed in a casing 8. The casing 8 has a peripheral wall 8a that surrounds the grid electrode 4. The casing 8 has a first opening/closing gate 8a1 that can be driven to open and close on a portion of the peripheral wall 8a. In FIG. 1, the casing 8 is illustrated with a portion of the peripheral wall 8a cut away.

In the illustrated example, the first opening/closing gate 8a1 is provided so as to be slidable up and down, and opens and closes up and down as the hoisting device 10 winds up and down the connected chain 9. The hoisting device 10 can be equipped with an electric motor and a winding roller, not shown. The first opening/closing gate 8a1 is a vertical opening/closing type in the illustrated example, but it can also be a horizontal opening/closing type. The first opening/closing gate 8a1 is provided to form an opening in the peripheral wall 8a for sending the fish tranquilized on the lattice electrode 4 to the next process, for example, to a live-killing stand, but it is also possible to provide a configuration in which the first opening/closing gate 8a1 is not provided and only an opening for sending the fish from the lattice electrode 4 is provided in part of the peripheral wall 8a.

The live fish tranquilizing system 1 is equipped with a tilting mechanism that tilts the lattice electrode 4. The tilting mechanism supports one end of the lattice electrode 4 so that it can rotate freely around a rotating shaft 11, and can tilt the lattice electrode 4 by winding up or rewinding the chain 12 connected to the other end of the lattice electrode 4 with a hoisting device 10 (see Figure 3).

The lattice electrode 4 is supported by a rotating shaft 11 on the side of the first opening/closing gate 8a1 so that it can rotate freely. When the hoisting device 10 is operated to lift the other end of the lattice electrode 4, the lattice electrode 4 tilts so that the side of the first opening/closing gate 8a1 is positioned lower, as shown in FIG. 3. When the lattice electrode 4 is tilted in this manner, the fish that have been sedated on the lattice electrode 4 slide down along the inclined surface of the lattice electrode 4 toward the first opening/closing gate 8a1, and the fish on the lattice electrode 4 are automatically sent out of the lattice electrode 4 through the first opening/closing gate 8a1.

The casing 8 includes a hopper section 13 that narrows downward and receives fish that fall from the gap G1 between the adjacent electrode bars 2 and 3 of the lattice electrode 4, and a chute section 14 that is connected to the lower end of the hopper section 13 and sends the fish that fall from the hopper section 13 to a predetermined location. In the illustrated example, the chute section 14 sends the fish that fall from the hopper section 13 to a first water tank 15 installed near the hopper section 13. The chute section 14 can also be configured to send the fish that fall from the hopper section 13 to, for example, an offshore fish pen instead of the first water tank 15. The fish that fall and are collected from the gap G1 can be returned to the fish farm and raised until they reach a size suitable for shipping.

In the illustrated example, the first opening/closing gate 8a1 and the hoisting device 10 of the tilting mechanism are shared by driving a single electric motor, and the opening operation of the first opening/closing gate 8a1 is linked to the tilting of the lattice electrode 4. As a result, when the first opening/closing gate 8a1 opens, the lattice electrode 4 tilts from a horizontal position to an inclined position so that the first opening/closing gate 8a1 side of the lattice electrode 4 becomes lower.

A retention section 16 is disposed adjacent to the lattice electrode 4, which temporarily retains live fish sent to the lattice electrode 4. The retention section 16 temporarily stores subsequent live fish while the lattice electrode 4 is energized, i.e., while the preceding live fish is being sedate-processed on the lattice electrode 4, and after the preceding live fish has been sedate-processed, the temporarily stored subsequent live fish is supplied onto the lattice electrode 4, thereby enabling the continuous sedate-processing of live fish supplied one after the other.

The retention section 16 is equipped with a sorting table 16a having a gap G2 formed therein for sorting and dropping fish smaller than a predetermined size. The size of the gap G2 can be smaller than the size of the gap G1, for example. For example, small fish other than those to be tranquilized can be sorted and dropped. The sorting table 16a can be configured with multiple rods 17 supported in parallel with the gap G2. The rods 17 may be made of metal or resin.

The sorting table 16a is arranged at an incline so that it becomes lower as it approaches the lattice electrode 4. The retention section 16 has a side wall 18 installed so as to surround the sorting table 16a, and is provided with a second opening/closing gate 19 between the retention section 16 and the lattice electrode 4. The second opening/closing gate 19 can be opened and closed vertically by winding up or rewinding the connected chain 20 with a winding device 21, as shown in FIG. 2.

The live fish which have been selected without falling through the gap G2 of the sorting table 16a slide along the inclined surface of the sorting table 16a and are sent onto the grid electrode 4 through the second opening/closing gate 19.
A second water tank 22 is provided below the sorting table 16a to receive the fish that fall from the sorting table 16a.

The retention section 16 is connected to a gutter-shaped live fish transport path 23. Live fish sucked up together with seawater from marine fish pens, etc. by a fish pump (not shown) are sent to the retention section 16 through the live fish transport path 23. Instead of a fish pump, live fish can be scooped up from the fish pens, etc. with a fish pen net and supplied to the retention section 16.

Live fish that do not fall through the gap G2 in the sorting table 16a and remain on the sorting table 16a slide down the inclined surface of the sorting table 16a and are sent onto the grid electrode 4 when the hoisting device 21 is operated to open the second opening and closing gate 19 as shown in Figure 2.

Live fish that fall through the gaps G1 of the lattice electrode 4 are discharged into the first tank 15. Press the on/off switch of the controller 5 to start passing electricity through the lattice electrode 4, and apply an electrical stimulus to the live fish that do not fall onto the lattice electrode 4 and remain there to calm them down. The controller 5 stops passing electricity after passing electricity for a specified period of time.

After the current is stopped, as shown in FIG. 3, the hoisting device 10 is operated to open the first opening/closing gate 8a1 and tilt the lattice electrode 4, causing the live fish that has been tranquilized on the lattice electrode 4 to slide down the lattice electrode 4 and be discharged from the first opening/closing gate 8a1. By linking the cessation of current with the opening operation of the first opening/closing gate 8a1 and the tilting of the lattice electrode 4, the live fish can be discharged from the first opening/closing gate 8a1 at the same time as the current is stopped. The tranquilized live fish discharged from the first opening/closing gate 8a1 are then subjected to processing such as killing in the next process.

The fish pump continues to operate while the lattice electrode 4 is energized, during which time the second opening and closing gate 19 is closed and the live fish supplied through the fish pump are temporarily retained in the retention section 16. The tranquilized live fish are discharged from the lattice electrode 4 through the first opening and closing gate 8a1, and after the opening and closing gate 8a1 is closed, the second opening and closing gate 19 is opened and the live fish retained in the retention section 16 are sent onto the lattice electrode 4. In this way, the live fish continuously supplied from marine fish pens etc. through the fish pump are almost continuously tranquilized.

Next, a second embodiment of the live fish tranquilizing system according to the present invention will be described with reference to FIG. 4. The live fish tranquilizing system 1B of the second embodiment is provided with a hopper section 16b and a chute section 16c below the sorting table 16a of the retention section 16, and live fish smaller than a predetermined size selected by the sorting table 16a are discharged from the hopper section 16b through the chute section 16c. The live fish discharged from the chute section 16c are returned to the original fish tank or the like through a conveying means 16d such as a trough. In the second embodiment, the gap G2 (see FIG. 1) of the sorting table 16a is set to a dimension that allows live fish that do not meet the size required for live-killing and shipping to be selected. As a result, live fish of a size suitable for live-killing are sent to the lattice electrode 4 during retention in the retention section 16, so that when the live fish are supplied to the lattice electrode 4, they can be immediately energized and tranquilized.

The live fish tranquilizing system 1B further includes a sorting table tilting mechanism that tilts the sorting table 16a. This sorting table tilting mechanism can be the same as the tilting mechanism for the lattice electrode 4, and tilts the sorting table 16a so that the lattice electrode 4 side of the sorting table 16a is positioned lower. In the illustrated example, the sorting table 16a is supported so that it can swing freely around one end of the sorting table 16a as a fulcrum, and the sorting table 16a can be tilted by winding up or rewinding the chain 21a connected to the other end of the sorting table 16a with the hoisting device 21. The second opening/closing gate 19 and the sorting table 16a are linked, and when the second opening/closing gate 19 opens, the other end of the sorting table 16a is lifted and tilted, allowing it to be tilted.

Furthermore, the live fish tranquilizing system 1B is equipped with a vibration imparting device 24 for vibrating the sorting table 16a to shake off live fish on the sorting table 16a that are smaller than a predetermined size through the gap G2 of the sorting table 16a. The vibration imparting device 24 can be constructed by attaching a vibration motor to the sorting table 16a. The vibration imparting device 24 is not limited to a vibration motor, and can be anything that can impart vibration to the sorting table 16a.

The present invention is not limited to the above embodiment, and various modifications are possible within the scope of the present invention. For example, in the above embodiment, a tilting mechanism for tilting the lattice electrode 4 is provided, but the tilting mechanism can be omitted. In the above embodiment, the retention section 16 is installed adjacent to the lattice electrode 4, but the retention section 16 and the lattice electrode 4 may be connected by a live fish transport path. In the above embodiment, the retention section 16 is installed, but the retention section 16 can be omitted. Also, a hopper and a chute section can be provided for each of the lattice electrode 4 and the sorting table 16. Also, the vibration imparting device in the second embodiment can be provided on the lattice electrode.

Reference Signs List 1, 1B Live fish tranquilizing system 2 Positive electrode rod 3 Negative electrode rod 4 Lattice electrode 5 Controller 8 Casing 8a1 First opening/closing gate 13 Hopper section 14 Chute section 15 First water tank 16 Retention section 16a Sorting table 19 Second opening/closing gate 22 Second water tank 24 Vibration imparting device G1 Gap G2 Gap

Claims (9)

A live fish tranquilizing system for tranquilizing live fish by passing an electric current through the fish,
a grid-like electrode in which electrode bars of different polarities are supported in parallel at intervals of a predetermined width;
A controller for controlling the output of current applied to the grid-shaped electrodes;
a casing that houses the grid electrode and surrounds the grid electrode and has a first opening/closing gate that can be opened and closed vertically;
a tilting mechanism for tilting the grid-like electrode;
a hoisting device that is connected to each of the first opening/closing gate and the lattice electrode via a chain and that links the first opening/closing gate and the tilting mechanism so that when the first opening/closing gate is opened, the side of the lattice electrode facing the first opening/closing gate is in a low inclined position, and when the first opening/closing gate is closed, the lattice electrode is horizontal;
The live fish tranquilizing system comprises: The live fish tranquilizing system according to claim 1 , further comprising a first water tank for receiving fish that fall through the gaps of the predetermined width between adjacent electrode bars. The live fish tranquilizing system of claim 1, wherein the casing comprises a hopper section that narrows downward to receive fish falling from the gaps between adjacent electrode bars, and a chute section connected to the lower end of the hopper section to send the fish falling from the hopper section to a predetermined location. A live fish tranquilizing system as described in any one of claims 1 to 3 , further comprising a retention section for temporarily retaining the live fish sent to the lattice electrode. The live fish tranquilizing system of claim 4 , further comprising a second opening/closing gate between the retention section and the lattice electrode, the second opening/closing gate being configured to close when electricity is applied to the lattice electrode. A live fish tranquilizing system as described in claim 4 or 5, wherein the retention section includes a sorting table having gaps formed therein for allowing fish smaller than a predetermined size to fall through, and is configured so that live fish that are sorted without falling through the gaps in the sorting table are sent onto the lattice electrode. The live fish tranquilizing system according to claim 6 , wherein the sorting table is arranged in an inclined manner so as to become lower as it approaches the grid-like electrode. Further comprising a sorting table tilting mechanism for tilting the sorting table,
The live fish tranquilizing system according to claim 6 , wherein the sorting table tilting mechanism tilts the sorting table so that the lattice electrode side of the sorting table is positioned lower. A live fish tranquilizing system as described in claim 6 or 7 , further comprising a vibration imparting device for vibrating the sorting table to shake off live fish on the sorting table that are smaller than a predetermined size through the gaps in the sorting table.