Animal husbandry – Aquatic animal culturing – Fish culturing
Reexamination Certificate
2000-03-02
2002-05-14
Jordan, Charles T. (Department: 3644)
Animal husbandry
Aquatic animal culturing
Fish culturing
C119S452000, C043S102000
Reexamination Certificate
active
06386146
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates generally to an aquaculture method and apparatus and, more particularly, to an aquaculture method and apparatus employing a cage formed out of a vertically contractible, non-buoyant mesh material.
Aquaculture is a rapidly expanding industry providing increasing quantities of various fish products. In comparison to conventional commercial fishing techniques, aquaculture offers the advantages of a predictable harvest and reduced labor and equipment cost. However, present systems are plagued with a variety of serious problems.
Typical aquaculture systems utilize weighted, fiber mesh nets suspended in a suitable water body by floatation rings. After a given growth period, the cage is lifted to the surface of the water body for harvest of a retained fish crop. Serious losses are caused in such aquaculture systems by large aquatic predators such as sharks, tuna and seals that easily penetrate the fiber mesh nets and feed upon the resident fish. Further losses occur when remaining fish escape through the openings created in the net by the predators.
To alleviate the predator problem, many aquaculture systems provide an auxiliary net that surrounds and is spaced from the fish retaining primary net. However, such protective netting also is subject to penetration by predators. Other disadvantages of currently employed fiber mesh nets are a requirement for extensive anchoring and a tendency for the flexible nets to be displaced by tidal flows and thereby undesirably crowd resident fish. An improved aquaculture system is disclosed in U.S. Pat. No. 5,967,086. That system includes a cage having contractible mesh side walls formed with relatively rigid, linked spiral wire resistant to planar deformation. Efficient farming operation, however, requires cages with side walls of a substantial size which creates a problem for transportation between a factory and a site of use.
The object of this invention, therefore, is to provide an improved aquaculture system that reduces problems inherently present in existing systems.
SUMMARY OF THE INVENTION
The invention is an aquaculture cage including a buoyant upper support for disposition at the surface of a water body; a side wall having an upper edge secured to the upper support so as to project below the surface of the water body, the side wall being formed with a plurality of vertically contractible, non-buoyant panels having vertically adjacent edges joined to form an enclosure and each of the joined vertical edges defining a plurality of vertically spaced apart loops; and an elongated connector element extending through the loops of the adjacent edges so as to secure together the panels. Also included is a bottom wall joined to the side wall to close the bottom of the enclosure. The use of panels permits convenient assembly of the cage at a site of desired use.
According to certain features of the invention, each panel is formed with metallic, spirally linked wires defining a mesh having substantial planar rigidity so as to resist horizontally directed deformation and end portions of the wires are formed into the loops which are aligned vertically. Efficient use of the cage is enhanced by these features.
According to another feature of the invention, the connector is substantially flaccid so as to be vertically contractible. The flaccid connector can collapse during contraction of the panels.
According to an additional feature of the invention, the mesh has interstices having a maximum diagonal of length D and loops have a minimum diagonal of length d greater than D. This feature restricts passage of the loops through the interstices thereby preventing the mesh from unraveling.
According to yet another feature, the invention includes a powered lift mechanism for applying upwardly directed force to the bottom so as to produce upward movement thereof and contraction of the panels. The lift mechanism is used during harvest of fish grown in the cage.
According to a further feature of the invention, the bottom includes a wire mesh central portion, and a rigid annular support disposed between a perimeter of the mesh portion and bottom edges of the panels. The central portion allows water passage and the rigid support facilitates contraction of the panels by the lift mechanism.
According to still another feature of the invention, a wire end portion has an inner portion formed into a loop and an outer portion wound around an inner section of the inner portion. These features provide efficient, stable loops for receiving the connector.
The invention also encompasses an aquaculture method including the steps of forming a plurality of contractible non-buoyant mesh panels having side, bottom and top edges; transporting the panels to a location having a water body; joining adjacent side edges of the panels to form an enclosure; and attaching a closure to the bottom edges to close the bottom of the enclosure. Additional steps include positioning the enclosure in the water body; supporting the enclosure from the surface of the water body with a buoyant support; growing a fish crop in the enclosure; applying a force to move the closure upwardly to contract the enclosure; and harvesting the fish crop at the surface of the water body.
According to one feature of the method, the forming step includes forming the panels with metallic, spirally linked wires having substantial rigidity so as to resist deformation by water currents and creatures, and forming loops with end portions of the wires at the side edges of the panels; and the joining step includes inserting an elongated connector element through the loops. These features facilitate assembly of the enclosure.
According to another feature of the method, the forming step includes forming an inner portion of each end portion into a loop, and winding an outer portion of each end portion around an inner section of the inner portion. These features provide efficient, stable loops.
REFERENCES:
patent: 2603028 (1952-07-01), Roberts
patent: 2854782 (1958-10-01), Daugherty
patent: 3374770 (1968-03-01), Freudenberger
patent: 4079698 (1978-03-01), Neff et al.
patent: 4084543 (1978-04-01), Pequegnat
patent: 4244323 (1981-01-01), Morimura
patent: 4257350 (1981-03-01), Streichenberger
patent: 4890413 (1990-01-01), Nelson et al.
patent: 5009189 (1991-04-01), Neff
patent: 5549076 (1996-08-01), Kaarstad
patent: 5617813 (1997-04-01), Loverich et al.
patent: 5967086 (1999-10-01), Knott, Sr.
Jarcho Harold G.
Jordan Charles T.
Nelson Judith A.
Toupal John E.
LandOfFree
Aquaculture method and apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Aquaculture method and apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Aquaculture method and apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2914502