FR2657750A1 - Self-supporting structure with controlled inversion for aquaculture and fish-breeding - Google Patents

Abstract

Device for supporting and changing the nets closed into a pouch in aquaculture and fish-breeding. A structure making it possible to change immersed nets from the surface without the need of human underwater intervention. This device is made up of a hollow module (1) on which valves (8) (9) (10) (11) permit or do not permit the entry of water and/or of pressurised air inside the module (1), as well as two ballasted frames (6) (3) connected, on the one hand, to the module (1) and, on the other hand, to buoys (4) by means of cables (7) passing through the frame structure (3). When an immersed valve (8) is opened, the water entering inside the module (1) makes it list as far as equilibrium with air trapped in the module. The immersion as far as the vertical is controlled by immersed valves (11). The exchange of the nets is done by deploying one (5) and folding back the other (2). This change causes a reverse unbalancing of the whole. Pressurised air is blown in through the valve (10), which expels the water through the valves (8) and (9). The module gradually recovers its buoyancy having described an angle of 180 DEG and thus performed its inversion.

Description

 Self-supporting structure with controlled inversion in open water.

 The present invention relates to structures serving as a support for pocket nets, forming rearing or protection basins in open water (sea or freshwater).

 Due to the permanent immersion of the nets, a proliferation of algae and concretions is created on their surface; the meshes are blocked, blocking all circulation of water. This results in a depletion of oxygen which generates an increase in ammonia and nitrites inside the enclosure. In order to remedy this, it is essential to exchange the nets as often as possible. The permanent presence of the animals makes this operation delicate. To achieve this, the pocket is doubled in place with a second pocket threaded from the bottom up to the surface. This maneuver requires a support allowing pedestrian circulation on its periphery, in the form of an expensive pontoon, two people on this pontoon, a scuba diver, that is to say a big investment in man and in material.

The self-supporting structure, object of the present invention, allows the exchange of a net in a pocket from the surface, by one or two people without plunger or circulation pontoon, by inversion of 1800 of the pre-installed assembly. (Dimensions: Length 4 to 8m Width 4 to 8m Depth 5m)
The structure is made up
- a module of integral plastic hollow tubes, in quadri form
latere, following the shape of the net on the surface.

- two frames in internally weighted tubes, of shape and
adequate construction, one placed at the bottom of the net, the other
on the cover of the module.

- sets of valves arranged in suitable locations on
the module and allowing inter communication between the interior
of the module with water and / or pressurized air.

 - cables connecting the module to the ballasted bottom.

 By maneuvering on the opening and / or closing of the valves as well as on the ropes of the structure, the assembly is brought back to 1800.

Presentation of the material
Plate 1/11: presents the floating module assembly (1) weighted frames (3) (13) and net (2).

 Plate 2/11: positioning of the control valves (8) (9) (10) (11) on the module (1) on each side (fig. 1 initial position / fig. 2 inverted position 1800).

 Plate 3/11: presents the frames fig. 3 (3) (13) with detail of the passage fig. (4-5-6) cables (7) (13) (14) in the frame.

Plate 4/11: preparation of the assembly before exchange of net including
- installation of the new net (5) on the cover (6) and
fixing the bottom of the net.

- fixing the new thread top (5) on the floating module
(1).

 Note the net in use (2) fixed and supported by the floating module (1), stretched by the weighted frame (3) this being connected on the one hand to the module (1) on the other hand free buoys (4).

 The valves (8) (9) (10) (11) are closed.

Operation
Plate 5/11: the opening of the valve (8) then of the valve (9) causes, by the entry of water inside the module, a gite followed by a progressive immersion and a tilting of the whole of the structure up to the equilibrium point between the pressure of the penetrating water and the compression of the air trapped in the module (1).

 Plate 6/11: the buoy (4) gives the ballasted frame (3) an upward movement and tends to move it away from the module (1) while creating a rotation up to 90 ".

 Plate 7/11: to allow the assembly to take a vertical position relative to the surface, the valves (10) and (11) will be used to gradually expel the compressed air inside the module (1) until 'to achieve the desired immersion.

 Plate 8/11: the new net (5) is deployed horizontally.

A buoy (12) is fixed to the rope (14) sliding in the weighted frame (6) and fixed to the module (1).

 Plate 9/11: The net to be changed (2) is brought back using the weighted frame (3) against the module (1), and in doing so, chases the animals in the new net (5). the net frame assembly is fixed to the module (1).

 Plate 10/11: a pressurized air supply is placed on the valve (10); the opening of the valve (10) flushes the water through the valves (8) and (9) and while the module (1) regains its buoyancy, the rope (14) is gradually released, releasing the weighted frame (6 ) which when inserted prints a rotation of the module (1) by 90 ".

 Board 11/11: as soon as the valve (8) is accessible, it is closed.

When the module reaches its emerged position and the water is completely evacuated, the valve (9) is closed. The buoy (12) is put on position and a buoy (4) is placed at the end of the line (13) for the next turnaround.

The used net can then be removed.

 Given the aquaculture development of the Mediterranean region, it is necessary to provide companies with practical and inexpensive equipment. Currently there is no material allowing an easy and achievable exchange of nets by aquaculturists who are not divers.

 On the other hand, the price of such a structure is half the price of the floating pontoons currently in existence and responding to the cry of open water.

Claims (5)

 1) Aquaculture device for supporting and changing fish and marine farming nets, in open water, from the surface, characterized by a module made of semi-rigid hollow tubes (1) on which valves have been fixed, by a game weighted frames (3) (13) and ropes (7) (14) (13).  2) Device according to claim N01 characterized in that the shape and the internal ballasting of the frames (3) (13) allow a regular tension of the net (2) (5).  3) Device according to claim N02 characterized in that the weighted frames (3) (13) are provided with table passages 3/11 fig. (3) (4) (5) (6) to guide the circulation of the ropes in their structure.  4) Device according to claim N "1 characterized in that the simultaneous and / or successive opening and / or closing of one or more valves (8) (9) (10) (11) allows the inlet and / or outlet of water and / or pressurized air.  5) Device according to claims NOl-2-3-4, characterized in that the judicious order of use of the air and / or water inlets and / or outlets allows the assembly of 800 to be turned over .