AU738470B2 - A mesh and a panel for use in Cultured Pearl Farming Operations - Google Patents

Description

P/00/01il 28/5/91 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Actual Inventors Address for service is: Atica Marine Pty Ltd Jerry George Ventouras, George Jerry Ventouras, Cliff Robert Green RA4 -o22-10 U1 .W9RAY ASCCOCIATIES ,1-Kc /~ltirle L+&4 2;39,Ndolaido Tcrrac fPO go- Preith, WNA 6999 HAMILON HIfLL wn~f 6103

I.

Attorney code: WR Invention Title: "A Mesh And A Panel For Use In Cultured Pearl Farming Operations" Details of Associated Provisional Application No: P08263 28 July 1997 The following statement is a full description of this invention, including the best method of performing it known to me-- -2- This invention relates to a mesh and a panel for use in cultured pearl farming operations.

In the farming of cultured pearls, a live oyster shell is usually deposited within a pocket formed in a pearl panel. Pearl panels come in two main types: one comprising a net attached to a substantially rigid frame; and the other comprising a folded plastic mesh arrangement. Both of these types are configured so that the panel has a plurality of pockets for supporting oyster shells therein, one in each pocket. During the farming operation, pearl panels are suspended from a buoyed line at spaced apart locations, approximately 10 feet below the surface i ~10 of the water, in order for the oysters to grow and culturing of pearls to occur within the live oyster.

In the past differently sized panels have been provided having pockets of sizes proportional to the size of the corresponding panel to accommodate So. appropriately sized oyster shells, depending upon the particular stage of the 15 farming operation. In this respect, oysters caught in the wild are housed within what are known as transportation panels having correspondingly sized small pockets that are used to hold the oyster shells during transport from their natural environment to the farming area. Upon arrival at the farm, the oyster shells are then operated on and then placed into holding panels which are generally 20 provided with a larger sized pocket to allow for growth of the oyster shell. Then, when the oyster shells have outgrown the holding panels and are ready for pearl culturing, the shells are transferred into growing panels having a larger size pocket again to accommodate relatively large sized oyster shells.

Any of these panels may be stored under the ocean for a period of two to four years and thus are generally subject to the growth of marine organisms such as algae and the like thereon. Consequently, panels configured such that the growth of these organisms is minimised are preferred to panels which promote their growth, in order to minimise maintenance and damage to the panels.

-3- Further, barnacles and similar organisms tend to grow on the oyster shells, which must be removed typically by using a chisel. Removing the oyster shell from its pocket to remove a barnacle is considered too time consuming. To avoid removing the oyster shell from its pocket, the barnacles are removed in situ, by chiselling at the barnacle through apertures in the pocket. Such chiselling creates a risk of damaging the pearl panel, especially the pocket.

Traditional pearl panels of the net and frame type utilise rope or cord configured in a mesh-like arrangement to provide the pockets for the oyster shells. These rope or cord pockets have generally required closing devices which are reasonably complex and time consuming to operate. The rope or cord also tends to collapse around the oyster shell, thus usually providing a reasonably tight fitting pocket which may restrict the growth of the oyster shell. A further *limitation of this type of panel is that the rope or cord is tied around and upon the frame, presenting a large number of discrete protrusions on the otherwise smooth surface of the frame. These protrusions unfortunately present ideal growth sites for marine organisms of the aforementioned type and consequently detract from the performance of the panel.

Pearl panels of the plastic mesh type use a simpler frame construction than the net and frame type panel and rely upon the use of a plastic mesh wrapped around the frame in a folded arrangement which is clipped together by a series of stainless steel staples to form the outline of discrete pockets. Since the mesh is disposed on the outside of the frame, again a large number of discrete protrusions are provided which similarly form ideal growing sites for marine organisms.

Additionally, such plastic mesh has included at least one flat surface. The edge between the flat and curved surfaces also presents an ideal growth site for algae.

-4- Some pearl panels have been made using commercially available plastic trellis mesh that is provided in large sheets. The plastic mesh must be cut to the size required for each pocket. Cutting the plastic mesh produces sharp edges which create a risk of injury to persons handling the pearl panel. A further limitation of using such plastic mesh is that the spacing of the mesh requires some degree of overlap between pockets. This overlapping makes it difficult to access the lower pockets and also creates an increased potential for algae growth and other marine fouling. Additionally, the plastic mesh is typically folded around the outside of the frame of the panel and clipped together to form the pockets. The discrete protrusions formed by the mesh folding around the outside of the frame again creates an ideal growth site for algae.

*The plastic mesh described above takes the form of a regular grid of squares.

The side length of each square varies between the different types of meshes and is typically in the range of 40 to 50mm. This grid size makes it difficult for persons maintaining the pearl panels to chisel barnacles from the oyster shells without damaging the plastic mesh. Increasing the mesh spacing such that the squares forming the mesh are larger provides better access to the oyster shells but at the cost of structural strength of the plastic mesh and consequently the pockets.

In accordance with a first aspect of this invention, there is provided a mesh for a pearl panel comprising a plurality of filaments arranged to form said mesh and define a plurality of apertures, wherein one of said apertures is provided substantially centrally in said mesh, said one aperture being relatively large when compared with the other apertures.

Preferably, said filaments approximate a grid, each filament defining a substantially arcuate path, or a piecewise-linear approximation thereof.

Preferably, the curvature of said arcuate paths of filaments adjacent said one aperture is greater than the curvature of the arcuate paths of filaments that are spaced from said one aperture.

Preferably, the ratio of the area of said one aperture to the area of any one of said other apertures is at least Preferably, said mesh further comprises a peripheral member, each filament being attached to said peripheral member.

Preferably, said filaments and said peripheral member are formed of a resilient flexible material.

Preferably, said filament and said peripheral member are circular or elliptical in cross-section.

In accordance with a second aspect of this invention, there is provided a mesh *for a pearl panel comprising at least two sections, each section comprising a plurality of filaments, said filaments arranged to form said mesh and define a V plurality of apertures, wherein one of said apertures in each section is provided substantially centrally in said section, each said one aperture being relatively large when compared with the other apertures in said section.

Preferably, said filaments approximate a grid, each filament defining a substantially arcuate path, or a piecewise-linear approximation thereof.

Preferably, the curvature of said arcuate paths of filaments adjacent one of said one apertures is greater than the curvature of the arcuate paths of filaments that are spaced from said one apertures.

Preferably, the ratio of the area of said one apertures to the area of any one of said other apertures is at least -6- Preferably, each section is provided with a peripheral member, each filament in each section being attached to a corresponding peripheral member.

Preferably, said filaments and said peripheral member are formed of a resilient flexible material.

Preferably, said filament and said peripheral member are circular or elliptical in cross-section.

Preferably, each section is approximately square in shape.

i In accordance with a third aspect of this invention, there is provided a pearl panel comprising a frame and a plurality of meshes according to the first or S 10 second aspect of this invention attached to said frame and arranged to define a ;.••plurality of pockets.

o *oIn one arrangement, each mesh is as defined in the second aspect of this invention, each mesh comprising two sections and being folded such that said two sections are opposed to define a pocket therebetween.

co In an alternative arrangement, each mesh is as in the second aspect of this invention, each mesh comprising two sections, wherein a first mesh extends .i across said frame in opposing relation to a second mesh, said first and second meshes being attached together to define two pockets.

Preferably, each mesh is attached to an inner surface of said frame.

The invention will now be described by way of three embodiments with reference to the accompanying drawings, in which: Figure 1 shows a mesh for use in a pearl panel according to the first embodiment; -7- Figure 2 shows a pearl panel according to a second embodiment of the invention; Figure 3 is an enlarged view of a top portion of the pearl panel shown in figure 2; Figure 4 is a cross-sectional view through A-A of the pearl panel shown in figure 2; Figure 5 shows a pearl panel according to a third embodiment of the invention; Figure 6 is an enlarged view of the top portion of the pearl panel shown in figure 5; and .t Figure 7 is a cross sectional view through B-B of the pearl panel shown in figure The first embodiment is directed towards a mesh 10 for a pearl panel which is shown in figure 1.

The mesh 10 comprises a first section 12 and a second section' 14, each of which comprises a peripheral member 16 and a plurality of filaments 18.

15 Each of the sections 12 and 14 are substantially square-shaped and are bounded by their respective peripheral member 16. The sections 12 and 14 are joined along one side to share a common portion 20 of each peripheral member 16. Each of the sections 12 and 14 has two truncated corners 22, being the corners remote from the common portion The filaments 18 in each of the sections 12 and 14 are arranged in a grid-like configuration and define a plurality of apertures 24. Each filament 18 extends between opposing sides of the respective section 12, 14 and is attached at each end thereof to the corresponding peripheral member 16. Each filament 18 approximates an arcuate path, with centrally disposed filaments with each -8section defining an arcuate path of greater curvature than filaments 18 that are more peripherally disposed.

A central aperture 26 is defined by the filaments 18 in each of the sections 12 and 14. Each aperture 26 is centrally disposed in its respective section 12, 14 and is defined by the four most centrally disposed filaments 18. Since the most centrally disposed filaments 18 have the greatest curvature, the central aperture 26 is relatively large when compared with the other apertures 24.

The filaments 18 and the peripheral members 16 are formed from a resilient, flexible plastics material and are substantially circular in cross-section.

10 The use of the mesh 10 will be described below in relation to the second and third embodiments.

The second embodiment comprises a panel 40 for use in pearl farming which is shown in figures 2,3 and 4.

The panel 40 comprises a rigid frame 42 and six meshes 10 arranged to form six pockets arranged in a 2x3 array. Each mesh 10 is folded about its common portion 20 such that the sections 12 and 14 of each mesh 10 are in an opposed relation. The common portion 20 is attached to the frame 42 by means of *i releasable fasteners 44. The frame 42 is sufficiently wide to receive two meshes when folded, one connected to each side of the frame 42. When the sections 12 and 14 of each of the two meshes are folded over, the ends of each of the meshes 10 remote from the common portion 20 are proximate each other and are connected together by means of releasable fasteners 46.

The two lowermost sides of each mesh 10 and one of the upper most sides of the mesh 10 therebeneath are connected together using releasable fasteners 48, thereby leaving an upper-most side 49 of each mesh 10 unattached. An -9opening 50 for each pocket is defined between the unattached side of 49 of each mesh 10 and the corresponding attached side thereof.

The fasteners 44, 46 and 48 are formed of stainless steel to avoid rusting when exposed to seawater. Stainless steel allows the fasteners to be opened and refastened, facilitating the replacement of a damaged mesh.

The truncated corners 22 on each mesh 10 prevent the corners of four adjacent meshes 10 from intersecting, thereby eliminating a potential algae growth site.

The panel 40 is also provided with a rope 52 that is used to suspend the panel from a buoyed line.

In use, a pearl shell is located within each of the pockets defined by the meshes and the panel 40 is suspended beneath the water from a buoy line. During maintenance of the panel 40, the central aperture 26 in each section 12 and 14 of each mesh 10 provides ready access to the pearl shells located therein, allowing the removal of barnacles and the like if necessary.

Further, the circular cross-section of the filaments 18 assists in reducing algae growth on the pearl panel 40. Similarly, attaching the meshes 10 to the inside of the frame 42 rather than folding the meshes 10 around the exterior of the frame o 42 reduces the number of protuberances around the frame 42, thereby also assisting in reducing the growth of algae. Further, the truncated corners 22 prevent the intersection of four adjacent meshes 10, thereby eliminating a further algae growth zone.

In this configuration, the opening 50 of each pocket is relatively wide.

The third embodiment is also directed towards a panel 70 for use in pearl farming and is shown in figures 5, 6 and 7.

The pearl panel 70 comprises a frame 72 and six meshes 10 arranged to provide six pockets in a 2x3 array.

The meshes 10 are arranged in pairs, with the meshes in each pair provided in an opposing relation to one another. Each mesh extends across the width of the frame 72. The ends of each mesh 10 are attached to the frame 72 at an inner surface using releasable fasteners 74. The common portion 20 of each mesh in the pair of meshes 10 are connected using releasable fasteners 76. The two lower-most sides of each mesh 10 in the pair of meshes are connected together and to the upper-most side of one of the meshes 10 in the pair of meshes below by releasable fasteners 78.

**In this embodiment, the pockets are formed between a pair of meshes extending across the frame 72. In this configuration, the openings of each of go the pockets is relatively narrow.

In use, the panel 70 is used in a similar manner to the panel 40 described in 15 relation to the second embodiment.

*4It should be appreciated that the scope of the present invention need not be limited to the particular scope of the embodiments described above.

For example, it is envisaged that in other embodiments, meshes will be folded into a generally "U"-shaped configuration and connected along each side to form a pocket with an opening at the open end of the

Claims (21)

1. A mesh for a pearl panel comprising a plurality of filaments arranged to form said mesh and define a plurality of apertures, wherein one of said apertures is provided substantially centrally in said mesh, said one aperture being relatively large when compared with the other apertures.

2. A mesh as claimed in claim 1, wherein said filaments approximate a grid, each filament defining a substantially arcuate path, or a piecewise-linear approximation thereof.

3. A mesh as claimed in claim 2, wherein the curvature of said arcuate paths of filaments adjacent said one aperture is greater than the curvature of the *arcuate paths of filaments that are spaced from said one aperture.

4. A mesh as claimed in any one of the preceding claims, wherein the ratio of o° ~the area of said one aperture to the area of any one of said other apertures is at least 15

5. A mesh as claimed in any one of the preceding claims, wherein said mesh further comprises a peripheral member, each filament being attached to said peripheral member.

6. A mesh as claimed in claim 5, wherein said filaments and said peripheral member are formed of a resilient flexible material.

7. A mesh as claimed in claim 5 or 6, wherein said filament and said peripheral member are circular or elliptical in cross-section.

8. A mesh for a pearl panel comprising at least two sections, each section comprising a plurality of filaments, said filaments arranged to form said mesh and define a plurality of apertures, wherein one of said apertures in -12- each section is provided substantially centrally in said section, each said one aperture being relatively large when compared with the other apertures in said section.

9. A mesh as claimed in claim 8, wherein said filaments approximate a grid, each filament defining a substantially arcuate path, or a piecewise-linear approximation thereof. A mesh as claimed in claim 9, wherein the curvature of said arcuate paths of filaments adjacent one of said one apertures is greater than the curvature of the arcuate paths of filaments that are spaced from said one apertures.

10

11. A mesh as claimed in any one of claims 8 to 10, wherein the ratio of the area of said one apertures to the area of any one of said other apertures is at least

12. A mesh as claimed in any one of claims 8 to 11, wherein each section is e *provided with a peripheral member, each filament in each section being attached to a corresponding peripheral member.

13. A mesh as claimed in claim 12, wherein said filaments and said peripheral member are formed of a resilient flexible material.

14. A mesh as claimed in claim 12 or 13, wherein said filament and said peripheral member are circular or elliptical in cross-section.

15. A mesh as claimed in any one of claims 8 to 14, wherein each section is approximately square in shape.

16. A mesh for a pearl panel substantially as herein described with reference to the accompanying drawings. -13-

17. A pearl panel comprising a frame and a plurality of meshes as defined in any one of the preceding claims attached to said frame and arranged to define a plurality of pockets.

18. A pearl panel as claimed in claim 17, wherein each mesh is as defined in any one of claims 8 to 15, each mesh comprising two sections and being folded such that said two sections are opposed to define a pocket therebetween.

19. A pearl panel as claimed in claim 17, wherein each mesh is as defined in any one of claims 8 to 15, each mesh comprising two sections, wherein a iiiil 10 first mesh extends across said frame in opposing relation to a second mesh, said first and second meshes being attached together to define two pockets.

20. A pearl panel as claimed in any one of claims 17 to 19, wherein each mesh is attached to an inner surface of said frame.

21. A pearl panel substantially as herein described with reference to the accompanying drawings. Dated this 28th day of July 1998. Atica Marine Pty Ltd Applicant Wray Associates Perth, Western Australia Patent Attorneys for the Applicant