Fish calming device

Abstract

[Problem] To provide a fish sedating device that can reliably electrify and sedate fish for a successful slaughter operation. [Solution] This fish sedating device is characterized by comprising: a fish placement means 3 capable of placing fish F thereon; electrodes 4a, 4b for electrifying the fish F placed on the fish placement means 3 through high-resistance water that is present on the fish placement means 3 and that has a higher electrical resistance than the fish; and a power source for electrifying the electrodes 4a, 4b.

Description

[Technical Field]

[0001] The present invention relates to a fish tranquilizer, and more particularly to a fish tranquilizer suitable for tranquilizing live fish that have been landed when they are killed. [Background technology]

[0002] Generally, if fish thrash about when they are landed, lactic acid builds up in their bodies, bruises form, and the quality of the fish deteriorates. Therefore, electric shocks have traditionally been used to calm fish before landing.

[0003] For example, a method has been proposed in which an electric current is passed between electrodes placed in water to give an electric shock to fish present between the electrodes, thereby tranquilizing them.

[0004] As an example, since seawater has a higher electrical conductivity than fish, simply passing a current between electrodes does not allow current to flow easily through fish in seawater. Therefore, it has been proposed to apply an electric shock to fish swimming near the net by passing a current through a net equipped with an electrode function that can pass electricity through fish in the water, thereby tranquilizing the fish, and then capturing the tranquilized fish in the net and removing them from the water (see Patent Document 1).

[0005] It has also been proposed to use a landing net to scoop up multiple fish with spines from the sea, and after all the fish have been taken out of the sea 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, tranquilizing the fish by electrocuting them to a degree that does not damage their spines, and then the tranquilized fish are taken out of the landing net and sent to the next process (see Patent Document 2).

[0006] In order to maintain the freshness of live fish after landing, they are often subjected to a killing process. In order to prevent the live fish from thrashing about during this killing process, it has been proposed to calm the live fish by placing them on a urethane mat and passing electricity between electrodes attached to the urethane mat. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-165720 [Patent Document 2] Japanese Patent Application Publication No. 2017-018028 Summary of the Invention [Problem to be solved by the invention]

[0008] When continuing the slaughtering process by passing electricity through live fish placed on a urethane mat as described above, there is an inconvenience that the electrodes used for passing electricity are electrically connected by so-called moisture, which consists of mucus and / or seawater and fresh water attached to the live fish, and the current mainly flows through the low-resistance moisture, which has a higher electrical conductivity than the live fish, and no electricity is passed through the live fish.

[0009] The present invention has been made in consideration of these points, and aims to provide a fish tranquilizing device that can reliably pass electricity through fish to tranquilize them and allow the killing operation to be carried out smoothly. [Means for solving the problem]

[0010] In order to achieve the above-mentioned object, a first form of fish calming device according to the present invention is characterized by having a fish placing means on which fish can be placed, an electrode that passes electricity through high-resistance water that is present in the fish placing means and has a higher electrical resistance than the fish, and a power source that passes electricity through the electrode.

[0011] By adopting this configuration, electricity can be reliably passed through electrodes to the fish placed on the fish placing means through the high-resistance water that is present in the fish placing means and has a higher electrical resistance than the fish, thereby calming them down and allowing the finishing operation to be carried out smoothly.

[0012] In addition, a second form of fish calming device according to the present invention is characterized by having a fish placing means on which fish can be placed, electrodes that pass electricity through high-resistance water that is present in the fish placing means and has a higher electrical resistance than the fish placed on the fish placing means, a power source that passes electricity through the electrodes, and water accumulation prevention means that prevents resistance-reducing water that reduces the electrical resistance between the electrodes from accumulating in the fish placing means.

[0013] Furthermore, by adopting this configuration, the moisture accumulation prevention means prevents the accumulation of resistance-reducing moisture that reduces the electrical resistance between the electrodes on the fish placing means, so that electricity can be reliably passed through the electrodes to calm the fish placed on the fish placing means, allowing the finishing work to be carried out smoothly.

[0014] Furthermore, a third form of the fish calming device according to the present invention is characterized in that in the first or second form, the resistance-reducing water contains at least one of mucus from the fish, seawater, and freshwater.

[0015] By adopting this configuration, resistance-reducing moisture, such as mucus adhering to the outer surface of the fish, mucus excreted from the body of the fish, seawater or freshwater brought in at the same time as the fish is placed on the fish placing means, and seawater or freshwater that may be added for the finishing operation, is appropriately removed by the moisture accumulation prevention means, and electricity can be reliably passed through the electrodes to calm the fish placed on the fish placing means, allowing the finishing operation to be carried out smoothly.

[0016] In addition, a fourth form of the fish calming device of the present invention is characterized in that, in any of the first to third forms, the water accumulation prevention means includes at least one of: being formed by providing a plurality of water passage holes in the thickness direction of the fish holding means; being formed by providing a vacuum means for forcibly discharging the resistance-reducing water from the fish holding means; and being formed by imparting a water-repellent function to the fish holding means.

[0017] By adopting such a configuration, resistance-reducing moisture near at least the fish on the fish-holding means is adequately removed by some type of moisture accumulation prevention means, and electricity can be reliably passed through electrodes to calm the fish on the fish-holding means, allowing the finishing operation to be carried out smoothly.

[0018] In addition, a fifth form of fish calming device according to the present invention is characterized in that, in any of the first to fourth forms, the fish placing means is elastic and is formed so as to make wide contact with the underside of the placing side of the fish placed thereon.

[0019] Furthermore, by adopting this configuration, there is wide contact between the underside of the fish placed on the elastic fish placing means and the upper surface of the elastically deformed fish placing means, so that electricity can be reliably passed through electrodes to calm the fish on the fish placing means, allowing the killing operation to be carried out smoothly. [Effects of the Invention]

[0020] According to the fish tranquilizing device of the present invention, it is possible to reliably pass electricity through the fish to tranquilize them and successfully carry out the killing operation. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a schematic perspective view showing one embodiment of a fish calming device according to the present invention; [Figure 2] Enlarged cross-sectional view along line II-II in Figure 1. [Figure 3] A cross-sectional view showing the mat elastically deforming with a fish placed on it. DETAILED DESCRIPTION OF THE INVENTION

[0022] 1 to 3 show one embodiment of the present invention, and a fish calming device 1 is installed on the deck of a fishing boat (not shown) as an example.

[0023] The fish tranquilizing device 1 comprises a rectangular urethane sponge mat 3 detachably placed on a rectangular resin workbench 2, and a pair of electrodes 4a, 4b (positive and negative electrodes) attached to the mat 3. The mat 3 is one type of fish placement means for placing fish in the present invention. The fish placement means is not limited to the mat 3 and may be made of any material suitable for the slaughtering of fish F, such as a resin plate, non-conductive metal, resin pipe, or netting. The workbench 2 is fixed to the deck by legs 2a. The pair of electrodes 4a, 4b are configured to be energized via a cable 6 from a power source (not shown) built into the electrical stimulation generator 5. The electrical stimulation generator 5 is equipped with a switch 7 for turning on and off the power to the electrodes 4a, 4b and for cutting off the power in an emergency.

[0024] To explain further, as shown in FIG. 2, the work table 2 is provided with a number of holes 8 penetrating in the thickness direction to remove moisture (resistance-reducing moisture) that reduces the electrical resistance between the electrodes 4a and 4b. As shown in FIG. 3, the mat 3 is formed so that when a fish F is placed on it, it elastically deforms and recesses, making wide contact with the underside of the side on which the fish F is placed. Furthermore, the mat 3 is formed to be porous or made of a water-repellent material to easily drain the resistance-reducing moisture on the upper surface. FIG. 2 shows an example in which a number of through holes 3a are formed in the mat 3 in the thickness direction. Furthermore, as a moisture accumulation prevention means to prevent resistance-reducing moisture from accumulating on the mat 3 at least near the fish F, a mechanism is formed to forcibly remove resistance-reducing moisture appropriately, including the mat 3 and work table 2. 2, a drain collection pan 9 in the form of a container that opens upward is fixed to the underside of the workbench 2 to temporarily collect the resistance-reducing water that flows downward through the numerous holes 8, and a drain discharge port 10 for discharging the collected drain is opened in the bottom surface of the drain collection pan 9, and a vacuum port 11 for drawing a vacuum is opened in the side surface of the drain collection pan 9. A vacuum pump (not shown) is connected to the vacuum port 11.

[0025] Next, the operation of this embodiment will be described.

[0026] When starting the process of finishing the fish F, first the switch 7 is turned on to energize the pair of electrodes 4a, 4b.

[0027] Next, the fish F is placed or dropped onto the upper surface of the mat 3. When the fish F is placed on the upper surface of the mat 3, the mat 3 elastically deforms and recesses according to the weight of the fish F, making wide contact with the underside of the placed fish F. In this state, electricity is passed through the pair of electrodes 4a, 4b to the fish F through an appropriate amount of moisture on the surface of the mat 3, tranquilizing the fish F. The slaughtering process is then carried out on the tranquilized fish F. Here, the appropriate amount of moisture on the surface of the mat 3 refers to moisture that is present in the mat 3, which is the fish placement means, and that has a higher electrical resistance than the fish F (high-resistance moisture), and the current passed through the pair of electrodes 4a, 4b flows through the high-resistance moisture and the fish F, ensuring that the fish F is electrocuted.

[0028] The above finishing process is carried out for each fish F in turn.

[0029] As this series of slaughtering operations is carried out on the fish F, so-called low-resistance water (resistance-reducing water) that has a lower electrical resistance than the fish F gradually accumulates, which is a combination of the mucous membranes attached to the surface of the fish F's body, the mucous membranes excreted from the fish F's body, and the seawater or freshwater that accumulates on the mat 3.

[0030] In this embodiment, the moisture accumulation prevention means functions to reliably prevent excess low-resistivity moisture (resistance-reducing moisture) from accumulating in the mat 3.

[0031] Specifically, negative pressure is created inside the drain storage pan 9 through the vacuum port 11, and excess low-resistance moisture (resistance-reduced moisture) near the mat 3 and the fish F is forcibly sucked through the porous parts of the mat 3 and the numerous holes 8 in the work table 2 and stored in the drain storage pan 9, and then drained from the drain storage pan 9 to the outside through the drain port 10.

[0032] In this way, the moisture accumulation prevention means adequately removes low-resistance moisture (resistance-reducing moisture) at least near the fish F on the mat 3, and electricity can be reliably passed through the electrodes 4a and 4b to calm the fish F on the mat 3, allowing the killing operation to be carried out smoothly.

[0033] In addition, the moisture accumulation prevention means may be formed by at least one of providing a large number of water-passing holes in the thickness direction of the mat 3, providing a vacuum means 11 for forcibly discharging resistance-reducing moisture from the mat 3, and imparting a water-repellent function to the mat 3.

[0034] The present invention is not limited to this configuration, and various modifications are possible as needed. The fish calming device of the present invention can be installed not only on fishing boats but also on land. [Explanation of symbols]

[0035] 1 Fish calming device 2 workbenches 3. Matt 4 electrodes 5 Electrical stimulation generator (built-in power supply) 6 Cables 7 Switch 8 holes 9 Drain pan 10 Drain port 11 Vacuum port

Claims

1. a fish placement means capable of placing fish; Moisture present in the fish placing means in contact with the fish placed on the fish placing means; an electrode that conducts electricity through the moisture; a power source for energizing the electrodes; A fish tranquilizing device comprising: The electrode is formed by a pair of electrodes spaced apart from each other on the fish-holding means, The water retention prevention means includes a water retention prevention means for preventing the accumulation of the mucous membrane of the fish, seawater, or freshwater, which is a resistance-reducing water that reduces the electrical resistance in the water present between the pair of electrodes, The fish placement means is formed by a plate-like member having a flat surface with no protrusions on its outer surface, and the water is stored on the flat surface, The moisture retention prevention means is a plurality of water passage holes provided in the thickness direction of the plate-like member of the fish placement means, which allow the resistance-reducing water stored on the flat surface of the plate-like member to pass to the underside of the plate-like member; A water-repellent function is imparted to the flat surface of the plate-like member; and The moisture present in the fish placement means is made high resistance moisture having an amount that makes the moisture present in the fish placement means higher in electrical resistance than the fish by the moisture accumulation prevention means. A fish calming device characterized by:

2. a fish placement means capable of placing fish; Moisture present in the fish placing means in contact with the fish placed on the fish placing means; an electrode that conducts electricity through the moisture; a power source for energizing the electrodes; A fish tranquilizing device comprising: The electrode is formed by a pair of electrodes spaced apart from each other on the fish-holding means, The water retention prevention means includes a water retention prevention means for preventing the accumulation of the mucous membrane of the fish, seawater, or freshwater, which is a resistance-reducing water that reduces the electrical resistance in the water present between the pair of electrodes, The fish placement means is formed by a plate-like portion having a flat surface on which the water is stored, The water accumulation prevention means converts the water present in the fish placement means into high-resistance water having an amount that makes the water have a higher electrical resistance than the fish, and by passing electricity through the pair of electrodes on the flat surface of the plate-like member, electricity is passed through the high-resistance water to calm the fish on the flat surface. A fish calming device characterized by:

3. 3. The fish calming device according to claim 1, wherein the resistance-reducing water contains at least one of mucus from the fish, seawater, and freshwater.

4. The fish calming device described in claim 1, characterized in that the moisture accumulation prevention means is formed by providing, in addition to at least one of the water passage holes and the water-repellent function, a vacuum means for forcibly expelling the resistance-reducing moisture from the fish placement means.

5. A fish calming device as described in any one of claims 1 to 4, characterized in that the fish placing means is elastic and is formed so as to make wide contact with the underside of the placing side of the fish placed thereon.

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