JPS5851733B2 - How to install an artificial reef - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an installation method in which an artificial fish reef suspended by a carrier vessel is sequentially lowered into the sea and is deposited on a predetermined seabed.

In recent years, against the backdrop of social demands to secure and multiply fish and shellfish, which form the core of Japan's important animal protein resources, it has become necessary to construct large-scale fish reef zones.

Artificial reefs have a long history, and were previously built using old wooden ships, trees, broken stones,
Extremely simple and small-scale fishing grounds have been created using dohyo rings, old iron materials, clay pipes, etc., but recently reinforced concrete three-dimensional frame-shaped blocks have become mainstream, but it is not possible to plan these concrete blocks as small blocks. If holes are made without proper placement, or if they are put in and left as they are, no matter how many of them are put in, they will not only be destroyed by currents and waves, or buried in drifting sand, making it difficult to produce a fish reef effect for a long period of time. At present, the location of the sinking is unclear due to hole drilling and random loading, which is causing problems in operations such as ``bottom trawl fishing'' and ``purse seine fishing.''

For this reason, planning and layout have become important issues.

Further, as described above, it is an important issue to sequentially deposit the artificial reefs at predetermined positions along the reference line.

For this reason, conventionally, target buoys, etc. are installed on both sides of the line to be sunk, a reference line is set between these two target buoys, the carrier is stopped at a predetermined position along this line, and the carrier is hoisted by the carrier. Artificial fish reefs are lowered into the sea one by one and placed on the seabed.

However, there are ocean currents in the sea, and the artificial fish reef suspended by a carrier vessel is swept away and swayed by the ocean current, so that it is not located directly below the carrier vessel (or is suspended at a position considerably offset from the carrier vessel). Particularly when the vessel is sunk in a deep seabed, the length of the suspended wire becomes quite long, so the position of the carrier vessel and the artificial reef suspended by it may be considerably misaligned. Ta.

For this reason, even if the carrier ship is stopped at a predetermined position, the artificial fish reef suspended in the sea by the carrier ship is shifted from the position of the carrier boat, so if it is sunk and installed in this shifted position, Therefore, there were cases in which the artificial reef could not be sunk in a predetermined position, so that the effect of the fish reef could not be fully demonstrated, and operations such as net fishing were sometimes hindered.

Additionally, there were times when the dialer was at risk when working on the deep seabed.

The present invention has been made to improve the above-mentioned situation, and its purpose is to provide an underwater propulsion device that automatically controls the underwater position of an artificial fish reef suspended on a carrier ship, To provide a method for installing an artificial fish reef that can be reliably placed on a predetermined seabed without shifting its position.

The present invention will be explained below with reference to embodiments shown in the drawings.

First, the artificial reef 1 used in this embodiment is one that has been widely used in the past, and consists of a ring body 2 and a rectangular frame body 3 that are successively connected by bolts into a horizontal triangular prism shape. The size can be configured arbitrarily.

After assembling the artificial reef 1 on land such as the coast,
Either it is lifted by a large crane or the like placed on the coast and lowered into the sea near a quay and placed on the seabed 4, or it is assembled and placed directly on the seabed 4.

Next, as shown in FIG. 1, a suspension boat 5 is positioned on the sea surface above the artificial reef 1 placed on the seabed 4. To briefly explain this suspension boat 5, Four wires 7 are connected to each prime number device 6 provided on each side of the front and rear sides.
The other ends of the wires 1 are hooked onto the hooks 9 on the upper side of the movable pulley 8 directly below the center of gravity of the hanging ship 50, and one end of the wire 10 of the movable pulley 8 is hooked. It is connected to a winch 11 disposed in the center of the hanging ship 5.

Then, the upper end of an underwater propulsion device 13, which will be described later, is hooked onto the hook 12 on the lower side of the movable pulley 8.

That is, as shown in FIG. 2, in the underwater propulsion device 13, the center portion of a propulsion device 15 disposed horizontally is swingably attached to the center portion of a mounting rod 14 disposed vertically. , this propulsion device 15 is always set to be horizontal in the sea, and if the attachment rod 14 is maintained vertically, the attachment angle of the propulsion device 15 to the attachment rod 14 is 90 degrees. Therefore, the propulsion unit 15 does not operate at all, but if the mounting rod 14 is tilted from vertical, the propulsion unit 15 will not operate at all after propulsion.
The mounting angle with the 90 degrees is different from 90 degrees.
When it deviates from 0 degrees, a current is sent from the carrier 5 through the cord 16 to the screw 1 disposed in front of the propulsion machine 15.
7 is automatically driven.

Then, the attachment ring 18 attached to the upper end of the attachment rod 14 is hooked onto the lower hook 12 and attached, and another attachment ring 19 is attached to the lower end of the attachment rod 14.

Further, a wire 21 is attached to a sling having a self-releasing hook 20 by gravity on the artificial reef 1 placed on the seabed 4.
After hooking both ends of the wire 210 to the attachment ring 19 provided at the lower end of the underwater propulsion device 13, the wire 10 is wound up by the winch 11, and the artificial reef 1 is slinged. is hoisted up and suspended in the sea directly below the center of gravity by the above-mentioned hanging ship 5.

In this way, the assembled artificial reef 1 is transported under the sea to a relatively deep position while being suspended in the sea just below the center of gravity of the hanging ship 50.

After the artificial reef 1 is transported underwater to a predetermined position, the hanging boat 5 is stopped at the predetermined position and the wire 10 is reeled back by the winch 11, so that the artificial reef 1 suspended by the hanging boat 5 is At this time, when the artificial reef 1 suspended by the hanging boat 5 is pushed by the ocean current, the reef 1 swings and deviates from the position directly below the hanging boat 5.

When the fish reef 1 swings and shifts, the mounting rod 14 of the hydraulic propulsion device 13 tilts at an angle of θ degrees with respect to the vertical line 22.
The propulsion unit 15 and the mounting rod 1 are always maintained in a horizontal state.
Since the mounting angle with respect to 4 deviates from 90 degrees, the screw 17 of the propulsion device 15 is automatically driven, the propulsion device 15 moves in the direction of arrow A, and the suspended artificial reef 1 is moved in the direction of arrow A. The artificial reef 1 is moved to a position directly below the hanging ship 5 (the position of the vertical line 22), and when this position is reached, the propulsion device 15 automatically stops, and the artificial reef 1 is moved again.
When the artificial fish reef 1 is swept away by the ocean current, the propulsion device 15 is activated, and thus the artificial reef 1 is always positioned directly below the hanging ship 5.

If the artificial reef 1 is lowered in this state, this artificial reef 1
surely reaches a predetermined position on the relatively deep seabed 4.

After the artificial reef 1 reaches the deep seabed 4, when the wire 10 is further unwound and loosened, the self-release hook 2
0 is released and the wire 21 is connected to the artificial reef 1.
When the wire 21 comes off automatically, the sling pulls up the wire 21 and the like using the winch 11.

In this way, the assembled artificial reef 1 is reliably deposited at a predetermined position on the relatively deep seabed 4.

Note that the hydraulic propulsion device 13 is not limited to the above-mentioned embodiments, but may be configured to automatically operate by detecting the displacement of the artificial reef 1 with respect to the carrier ship 5 using a light receiving element or by detecting pressure. Of course, there is no problem.

As detailed above, the present invention provides an underwater propulsion device that automatically controls the underwater position of the artificial reef in the vicinity of the artificial reef suspended on a carrier, and uses this underwater propulsion device to move the artificial reef to the carrier. It is characterized by being placed on the seabed while controlling its position.

Therefore, when an artificial reef suspended by a carrier vessel is swept away by ocean currents and deviates from the position of the carrier vessel, the underwater propulsion device automatically operates to correct the position of the artificial reef with respect to the carrier vessel. Since the artificial reef will not shift, by stopping the carrier vessel in a designated position, the artificial reef can be reliably deposited at the designated location on the seabed, and the reef effect can be fully exerted, and it will not interfere with operations such as net fishing. It won't cause any harm.

Furthermore, since the underwater propulsion device operates automatically, there is no need for a dipper or the like to work underwater, making the operation easy and safe.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention, FIG. 2 is a perspective view of an underwater propulsion device of the same embodiment, and FIG. 3 is an explanatory diagram illustrating the operation of the same embodiment. 1...Artificial reef, 5...Carrier ship? ,
10゜21... Each wire 13...
Hydraulic propulsion device.

Claims (1)

[Claims] 1. In a system in which an artificial fish reef suspended by a carrier vessel is lowered into the sea one after another and deposited on a predetermined seabed, an underwater propulsion device is installed near the suspended artificial reef to automatically control the position of the artificial reef in the sea. 1. A method for installing an artificial fish reef, characterized in that the underwater propulsion device is used to control the position of the artificial reef with respect to a carrier ship while sinking the artificial reef into the seabed.