JP2016182072A - Net body, trawl system, and fishing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance reliability of expanding a fishnet in a bag-shaped net body having a part of an opening in contact with a water bottom.SOLUTION: A net body 20 includes: a ground rope 30; bobbins 51, 52; and a net 22. Each of the bobbins 51, 52 includes: a base body 53 attached on the ground rope 30; and a blade 54 arranged on an outer periphery of the base body 53 so as to be inclined with respect to a plane perpendicular to the ground rope 30. The net 22 is formed in a bag shape with a part of an edge of an opening attached in an area sandwiching the bobbins 51, 52 of the ground rope 30. The ground rope 30 is moved in a towing direction 90 crossing an extention direction of the ground rope 30, thereby the bobbins 51, 52 in contact with the water bottom deform the ground rope 30 so as to approach a straight line perpendicular to the towing direction 90.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a bag-shaped net whose part of an opening is in contact with a water bottom, a trawl system using the net, and a fishing method.

  In bottom net fishing, the nets are expanded, especially in the horizontal direction, using methods such as double-hulling, turning, and otter trawling. The two-handed ship is towed while opening the net with two ships.

  First, the tow line is dropped into the sea and towed while one end of one tow line is connected to the buoy. When the tow line is submerged to some extent, the direction is changed and the tow is further towed. Proceed further, after dropping the net, turn slightly to approach the buoy side. After that, with the net opening fully open, the ship is brought close to the buoy and the end of the towline is recovered. In this way, fishing is performed by advancing the ship while pulling the net in a state where the pulling lines on both sides of the net are secured on the ship.

  In the otter trawl, a winged otter plate is placed on each of the two pull ropes near the net. By pulling the towline in this state, the otter board receives a force in the direction of spreading in the water flow. Thereby, the opening part of a net | network spreads in a horizontal direction.

JP 2002-315472 A

  When bottoming net fishing is performed, the fuel cost for two fishing boats is required for double fishing. In addition, operators and workers are required for each ship. For this reason, more energy is consumed and costs tend to be higher than fishing at a glance.

  In sprinkling, a special net spreader is not used, so the time required to start fishing increases. In addition, the opening that has once expanded closes in a few tens of minutes, and cannot be kept for a long time. For this reason, it is difficult to fish efficiently.

  The otter board used in the otter troll is large in order to obtain a relatively large net expansion force. For this reason, otter boards tend to be heavy. Therefore, handling a large and heavy otter board requires a lot of labor and is difficult to work.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to improve the reliability of expansion of a bag-like net body in which a part of the opening is in contact with the water bottom, and to improve workability without requiring a large amount of labor.

  In order to achieve the above-mentioned object, the present invention provides a ground rope attached to a portion in contact with a water bottom, a base attached to the ground rope, and an outer periphery of the base in an inclined manner with respect to a towing direction. And a bag-like net having a part of the edge of the opening attached to the ground rope.

  In the troll system, the present invention includes a ground rope attached to a portion in contact with the water bottom, a base body attached to the ground rope, and a blade provided on the outer periphery of the base body with an inclination with respect to the towing direction. A net having a bobbin, a bag-like net having a part of an edge of an opening attached to the ground rope, and a ship that pulls both ends of the ground rope. .

  Further, in the fishing method, the present invention includes a ground rope attached to a portion in contact with the bottom of the water, a base attached to the ground rope, and a blade provided on the outer periphery of the base with an inclination with respect to the towing direction. And pulling both ends of the ground rope with a single ship using a net having a bobbin and a bag-like net with a part of the edge of the opening attached to the ground rope. Features.

  According to the present invention, in the bag-like net body in which a part of the opening is in contact with the water bottom, the reliability of the expansion of the net is increased, and a large amount of labor is not required, thereby improving workability.

1 is a perspective view of a first embodiment of a net according to the present invention. It is a front view which shows typically partial expansion of 1st Embodiment of the net | network body which concerns on this invention. It is a top view which shows typically the moving direction of a bobbin, and the force which acts on a bobbin in 1st Embodiment of the net | network body which concerns on this invention. It is a perspective view which shows typically the fishing method performed using 1st Embodiment of the net body which concerns on this invention. It is a front view which shows typically a partial expansion of 2nd Embodiment of the net | network body which concerns on this invention.

  Several embodiments of a mesh body according to the present invention will be described with reference to the drawings. This embodiment is merely an example, and the present invention is not limited to this. The same or similar components are denoted by the same reference numerals, and redundant description is omitted.

[First Embodiment]
FIG. 1 is a perspective view of a net body according to the present embodiment. FIG. 2 is a partially enlarged front view of the net body of the present embodiment.

  The net body 20 of the present embodiment includes a net 22, a ground rope 30, and bobbins 51 and 52. The bobbins 51 and 52 have a base 53 and blades 54.

  The base 53 is attached to the ground rope 30. For example, a through hole is formed in the base 53, and the base 53 is attached to the ground rope 30 by inserting the ground rope 30 into the through hole. In FIG. 2, the base bodies 53 are schematically shown so as to be spaced apart from each other. However, in actuality, the bases 53 are inserted without any gaps, and the two pieces at both ends are locked by the metal fittings 58 so that they do not come out and do not move. To be made.

  The blades 54 are provided on the outer periphery of the base 53 so as to be inclined with respect to the towing direction 90. The bobbins 51 and 52 are classified into a first bobbin 51 and a second bobbin 52 according to the direction of the blades 54. The sign of the tilt angle of the first bobbin 51 with respect to the towing direction 90, that is, the sign of the tilt angle, differs from the tilt angle of the second bobbin 52 with respect to the towing direction 90. For example, the blades 54 of the second bobbin 52 are symmetrical to the blades 54 of the first bobbin 51 with a vertical plane parallel to the towing direction 90 as a symmetry plane. For example, a plurality of blades 54 are provided for one base 53.

  The first bobbin 51 is disposed on one side with respect to the boundary point 27 located at the center of the ground rope 30. The second bobbin 52 is disposed on the side opposite to the first bobbin 51 with respect to the boundary point 27. Both the first bobbin 51 and the second bobbin 52 are arranged on the front sleeve, which is a straight line when the opening of the net expands in a substantially U shape by towing. A third bobbin 50 is disposed on the rear sleeve, which is a substantially U-shaped curved portion. The third bobbin 50 is formed only by the base 53 without the blades 54.

  The net 22 has a bag shape with an opening. The lower edge of the opening of the net 22 is attached to the ground rope 30. A floating body 40 is attached to the upper edge of the opening of the net 22. That is, the edge of the opening of the net 22 includes a portion attached to the ground rope 30 to which the bobbins 50, 51 and 52 are attached, and a portion opposite to the portion to which the floating body 40 is attached. .

  The bobbins 50, 51, 52 have a specific gravity greater than seawater. The floating body 40 has a specific gravity smaller than seawater. For example, the base 53 is made of rubber containing iron, and the bobbins 51 and 52 are obtained by attaching iron blades 54 to the base 53. The bobbins 51 and 52 should have a specific gravity so as to come into contact with the bottom 80 with a pressing force enough to receive contact resistance from the bottom 80, considering the buoyancy of other components such as the ground rope 30, the floating body 40, and the net 22. I must. The floating body 40 is made of, for example, a synthetic resin.

  FIG. 3 is a top view schematically showing the moving direction of the bobbin and the force acting on the bobbin in the present embodiment.

  When the ground rope 30 (see FIG. 1 and the like) moves in the towing direction 90, the second bobbin 52 comes into contact with a water bottom 80 (see FIG. 4) such as sand and mud, thereby causing a force 93 in a direction perpendicular to the blades 54. Receive. A component 91 of the force 93 in a direction perpendicular to the towing direction 90 acts on the ground rope 30 in a leftward direction in the towing direction.

  Similarly, a component force in a direction perpendicular to the towing direction 90 acts on the first bobbin 51 with respect to the ground rope 30. However, the component force acting on the first bobbin 51 acts in a direction symmetrical to the towing direction 90 of the component force 91 acting on the second bobbin 52.

  Although the third bobbin 50 is not provided with the blades 54, a similar component force is generated depending on the angle of the base 53 with respect to the towing direction. That is, when the third bobbin 50 is arranged on the left side of the ground rope 30 like the second bobbin 52 and on the rear sleeve, which is a curved portion when it is substantially U-shaped, the length of the third bobbin 50 The direction, ie the through-hole direction, is inclined counterclockwise with respect to the towing direction. Therefore, a force in a leftward direction acts on the third bobbin 50 in the towing direction as in the second bobbin 52.

  Similarly, when the third bobbin 50 is disposed on the right side of the ground rope 30 and on the rear sleeve, like the first bobbin 51, a force acts in the same direction as the first bobbin 51.

  As a result, the ground rope 30 becomes substantially U-shaped by towing, and the opening of the net 22 can be expanded in the lateral direction.

  FIG. 4 is a perspective view schematically showing a fishing method performed using the net body of the present embodiment.

  When bottom net fishing is performed using the net body 20, the two pull ropes 24 respectively connected to both ends of the ground rope 30 are pulled by a single ship 10. At this time, the ground rope 30 spreads left and right by the action of the bobbins 50, 51, 52. Further, the upper edge of the opening of the net 22 is raised by the action of the floating body 40 provided in the net body 20. In this way, the opening of the net 22 is expanded. As a result, the net 22 moves starting from the opening with the opening open, and fish and other organisms / objects to be fished enter the net 22 from the opening.

  Thus, the net body 20 of the present embodiment deforms the ground rope 30 into a substantially U shape by moving the bobbins 50, 51, 52 while contacting the water bottom 80. That is, the openness of the opening of the net 20 is naturally secured. Since the force generated by the water flow is not used, the openness of the opening of the net body 20 can be secured even at a low net speed of about 2 to 4 knots in bottom fishing.

  Further, since the ground rope 30 is deformed into a substantially U shape by the bobbins 50, 51, 52, even if both ends of the ground rope 30 are pulled by a single ship, that is, substantially at one point, the expansion of the net Certainty can be maintained. On the other hand, since the net body 20 is rowed by a single ship, the net body 20 can be easily moved while suppressing fuel costs and labor costs compared to the case where both ends of the ground rope 30 are run by two ships. Fishing. Furthermore, since heavy objects such as an otter board are not used, less energy is consumed.

  As described above, according to the present embodiment, in the bag-like net body in which a part of the opening is in contact with the water bottom, the net body can be easily moved while maintaining the certainty of the expansion. .

[Second Embodiment]
FIG. 5 is a front view schematically showing a partial enlargement of the second embodiment of the net according to the present invention.

  In the net body 20 of the present embodiment, the angles of the blades 54 provided on the first bobbin 51 and the second bobbin 52 are different from those of the first embodiment. The angle with respect to the towing direction 90 (see FIG. 1) of the blades 54 provided on the first bobbin 51 disposed on the rear sleeve, which is a curved portion when the ground rope 30 is substantially U-shaped, is determined by the ground rope 30. It is the same as the blade | wing 54 provided in the 1st bobbin 51 arrange | positioned at the front sleeve which is a linear part when it becomes a substantially U shape.

  In the curved portion that is the rear sleeve of the ground rope 30, the inclination angle of the base 53 with respect to the towing direction 90 differs depending on the position. For this reason, the angle with respect to the longitudinal direction of the base | substrate 53, ie, the through-hole direction, of the blade | wing 54 provided in the 1st bobbin 51 arrange | positioned at the curved part which is a back sleeve changes with places.

  The angle with respect to the towing direction 90 (see FIG. 1) of the blades 54 provided on the second bobbin 52 disposed on the rear sleeve, which is a curved portion when the ground rope 30 is substantially U-shaped, is determined by the ground rope 30. It is the same as the blade | wing 54 provided in the 2nd bobbin 52 arrange | positioned at the front sleeve which is a linear part when it becomes a substantially U shape. That is, as in the case of the first bobbin 51, the angle of the blades 54 provided on the second bobbin 52 arranged on the curved portion that is the rear sleeve with respect to the longitudinal direction of the base 53, that is, the through-hole direction, is the place where it is arranged. It depends on.

  According to the present embodiment, as in the first embodiment, in the bag-like net body in which a part of the opening is in contact with the water bottom, the net body can be easily moved while maintaining the reliability of the net expansion. Can be. Furthermore, a reliable net expansion force can be obtained for the bobbin disposed in the rear sleeve portion. In addition, the angle of the blade | wing 54 provided in the bobbin is not limited to the example of these embodiment.

DESCRIPTION OF SYMBOLS 10 ... Ship, 20 ... Net body, 22 ... Net, 24 ... Pull rope, 27 ... Boundary point, 30 ... Ground rope, 40 ... Floating body, 51 ... First bobbin, 52 ... Second bobbin, 53 ... Base body, 54 ... Feather, 58 ... metal fitting, 80 ... bottom of water, 90 ... towing direction

Claims (6)

A ground rope attached to the part in contact with the bottom of the water;
A bobbin provided with a base body attached to the ground rope and a blade provided on the outer periphery of the base body with an inclination with respect to the towing direction;
A bag-like net with a part of the edge of the opening attached to the ground rope;
A mesh body characterized by comprising:   The net body according to claim 1, wherein the bobbin includes a first bobbin and a second bobbin having a sign of an inclination angle with respect to a towing direction of the blade with respect to the first bobbin.   The net body according to claim 1, wherein the bobbin has a specific gravity greater than seawater.   The net body according to any one of claims 1 to 3, further comprising a floating body having a specific gravity smaller than seawater attached to a region other than a region attached to the ground rope at an edge of the opening. . A bobbin provided with a ground rope attached to a portion in contact with the bottom of the water, a base attached to the ground rope, and a blade provided on the outer periphery of the base with an inclination relative to the towing direction; and an edge of the opening in the ground rope A net having a bag-like net attached to a part of
A ship that pulls both ends of the ground rope;
A trawl system comprising: A bobbin provided with a ground rope attached to a portion in contact with the bottom of the water, a base attached to the ground rope, and a blade provided on the outer periphery of the base with an inclination relative to the towing direction; and an edge of the opening in the ground rope A fishing method, comprising: using a net having a bag-like net attached to a part of the ground rope, and pulling both ends of the ground rope with a single ship.

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