KR102278555B1 - Shell arrangement device for farming oyster - Google Patents

Abstract

The present invention relates to a shell alignment device for oyster culture, and more particularly, an oyster culture that can automatically sequentially align a hole by drilling a hole in the shell, and can automatically sequentially align a tube for maintaining a gap between shells if necessary It relates to a shell alignment device for dragons.
The shell alignment apparatus for oyster culture according to the present invention comprises: a drilling machine including a drill for drilling a hole in the shell vertically in the upper direction of the shell placed in a predetermined position; a support part on which the shell is placed before the shell's hole is drilled, and rotates in one direction when the shell's hole is drilled by the drilling machine so that the shell falls down; The drill and the center line coincide with the alignment bar, which is located below the support part, and is aligned with a perforated shell threaded therein; may be included.

Description

Shell sorting device for oyster culture {SHELL ARRANGEMENT DEVICE FOR FARMING OYSTER}

The present invention relates to a shell alignment device for oyster culture, and more particularly, an oyster culture that can automatically sequentially align a hole by drilling a hole in the shell, and automatically sequentially align a tube for maintaining a gap between shells, if necessary It relates to a shell alignment device for dragons.

In general, oysters are cultured by hanging scallop shells (hereinafter referred to as "shells") on a line at regular intervals in a submerged oyster farm.

Conventionally, a line for hanging shells is a synthetic resin-coated braid made of a material that can withstand the floor for a long time, coated with a synthetic resin-coated wire, and is called a suha-yeon.

In the conventional hanging-type oyster shells, a plurality of shells are hung at regular intervals on a rope hanging on a rope installed at a certain height above the surface of the sea. In this case, in order to hang a plurality of shells at regular intervals on the bottom edge of the sea, Bundled knots should be formed at regular intervals on the lower part of the body.

However, in order to hang a plurality of shells at regular intervals on the lower lip, a method of threading a plurality of shells on the lower lip in advance, and then forming bundle knots on the lower lip at regular intervals so that the plurality of shells can be positioned at regular intervals A plurality of shells are hung at regular intervals.

This conventional method is by a method of forming a connecting knot on the lower lip and inserting a shell, forming a connecting knot again, and alternately fitting the shell.

However, since dozens of shells have to be sewn into one suha-yeon, it is very difficult and labor cost is high by manually doing it one by one.

Various methods have been developed to solve these problems, and are disclosed in Korean Patent Application Laid-Open No. 10-2017-0088564 as 'a mathematically automated shell binding apparatus and method for oyster culture'.

However, Korean Patent Laid-Open Publication No. 10-2017-0088564 has a problem in that the binding device is complicated, and in addition, dozens of shells have to be sewn, but this part has a problem in that it has to be done manually.

The present applicant has also been conducting various studies such as Utility Model 20-0481879, Patent 10-1564082, Patent 10-1564080, and Patent 10-1564081 to solve these problems.

: Republic of Korea Patent Publication 10-2017-0088564 : Republic of Korea utility model registration 20-0481879 : Republic of Korea Patent 10-1564082 : Republic of Korea Patent 10-1564080 : Republic of Korea Patent 10-1564081

An object of the present invention for solving the above-mentioned conventional problems is to provide a device capable of automatically aligning dozens of shells on the lower edge, which takes precedence over the automatic binding device of shells for oyster culture.

In addition, an object of the present invention is to provide a device capable of alternately aligning the gap maintaining tubes with the shells so that a predetermined interval can be maintained between the aligned dozens of shells and the shells.

In addition, the sorted shells can be stored separately by locating them in a certain pipe or steel material, and it is intended to be used as an independent shell sorting product group so that it can be used for automatic alignment.

A shell alignment apparatus for oyster culture according to the present invention for achieving the above object, a drilling machine including a drill for drilling a hole in the shell vertically in the upper direction of the shell placed in a predetermined position; a support part on which the shell is placed before the shell's hole is drilled, and rotates in one direction when the shell's hole is drilled by the drilling machine so that the shell falls down; The drill and the center line coincide with the alignment bar positioned below the support, the shells are arranged in sequence with the perforated shell threaded; may be made to include.

Here, the support portion is made of a pair of left and right in a symmetrical structure, each of the support portions abutting each other in a horizontal state to form a support shape, hinge-coupled to both ends, it is preferable that the structure is rotated in the opposite downward direction to open.

Here, the drill is movable in the downward direction, and at the time of drilling the hole of the shell, the tip of the drill and the tip of the alignment bar are preferably spaced apart from each other by a predetermined distance so that the shell is not separated.

Here, the alignment bar may have a straight or 'L' shape, a pipe shape, or an iron core without an inner diameter.

Here, the alignment bar has a 'L' shape in which a vertical part and a horizontal part are combined, a vertical fixing part supporting the horizontal part is further formed, and the vertical fixing part is hinged to one end and can be rotated.

Here, on one side of the alignment bar, a transfer unit for horizontally moving by a cylinder to move the shell located in the horizontal portion in the other direction may be further formed.

Here, a horizontal fixing unit for supporting a portion in which the alignment bar is bent by moving horizontally with the conveying unit by the cylinder may be further formed.

Here, one end is hinged to the upper side of the support and further comprises a rotating tube transfer insert, wherein the tube transfer insert is alternated with the shell by transporting a gap maintaining tube for maintaining a gap between the shells aligned on the alignment bar. It can be implemented to insert so that it can be sorted logically.

Here, a tube insertion hole is formed in the center of the support portion, a guide is formed in a horizontal direction in front, the tube transfer insertion portion is formed with a tube seating portion, and the tube seating portion coincides with the tube insertion hole and the center point by rotation. it is preferable

According to the above-described configuration of the present invention, it is possible to provide a device capable of automatically aligning dozens of shells on the lower lip, which takes precedence over the automatic binding device of shells for oyster culture.

In addition, it is possible to provide a device capable of alternately aligning the gap maintaining tubes with the shells so as to maintain a predetermined interval between the aligned dozens of shells and shells.

In addition, it is possible to separate the sorted shells by placing them in a certain pipe or steel material, and it can be used as an independent shell sorting product group for automatic sorting.

In addition, since the automation device is simple and can be manufactured at a low cost, it is possible to significantly reduce the cost of the automation device together with the reduction of the existing labor cost.

1 and 2 are schematic views of a shell alignment device for vertical oyster culture according to an embodiment of the present invention.
3 to 5 are schematic views of a shell alignment device for horizontal oyster culture according to another embodiment of the present invention.
Figure 6 is a schematic view of adding an automatic insertion device for maintaining the spacing between the shells to the shell alignment device for vertical oyster culture according to an embodiment of the present invention.
7 is a perspective view of the support and the tube transfer insert applied to the vertical oyster shell alignment device according to an embodiment of the present invention.

Hereinafter, the structure and effect of the shell alignment device for oyster culture according to the present invention will be described with reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The detailed description of specific embodiments shown in the accompanying drawings is read in conjunction with the accompanying drawings, which are considered to be part of the entire description of the invention. References to directions or directions are for convenience of description only, and are not intended to limit the scope of the present invention in any way.

Specifically, terms indicating positions such as "down, up, horizontal, vertical, upper, lower, upward, downward, upper, lower", or derivatives thereof (for example, "horizontally, downwardly, upwardly") etc.) should be understood with reference to both the drawings and related descriptions being described. In particular, since these relative words are only for convenience of description, it is not required that the device of the present invention be configured or operated in a specific direction.

In addition, terms indicating a mutual coupling relationship between components such as "mounted, attached, connected, connected, interconnected", unless otherwise specified, refer to a state in which individual components are directly or indirectly attached, connected, or fixed. can mean, and this should be understood as a term encompassing a state in which it is movable, attached, connected, fixed, as well as a state in which it cannot be moved.

In adding reference numerals to the components of each drawing, it should be noted that the same components are given the same reference numerals as much as possible even though they are indicated on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

The shell aligning device for oyster culture of the present invention discloses a vertical shell arranging device for oyster culture as shown in FIGS. 1 and 2 according to a shell alignment method, and a horizontal shell arranging device for oyster culture as shown in FIGS. 3 to 5 . is disclosed, and an automated device for maintaining the gap between the shells is added as shown in FIGS. 6 and 7 .

For shells for oyster culture, a shell mounting part (previously bundled knot) is formed at a certain height on the lower edge (synthetic resin-coated braided yarn covered with a synthetic resin covering wire), and one shell is mounted on the shell holding part, resulting in dozens of shells. It is lined up with a certain distance from top to bottom, and it is lowered down to the sea farm and applied to the oyster aquaculture industry.

The shell alignment device for oyster culture of the present invention automatically drills a hole for threading dozens of shells on the lower limb before hanging on the lower limb, and at the same time the hole is drilled, an alignment rod (a pipe having an inner hole or an inner hole) Provided is a device for sequentially aligning to the non-iron core), and a device for alternately inserting a spacer tube to maintain a gap between the aligned shells.

The shells aligned on the sorting bar can then be mounted on the lower lip by a separate device of the same process, or can be stored and stored independently in units of the sorting bar in which the shells are aligned, so that the shells can be stored with a separate automated device or manually in the future. It has the form of a standalone product that can be hung on the lower edge.

1 and 2 are schematic views of a shell alignment device for vertical oyster culture according to an embodiment of the present invention.

1 is a state diagram before a hole is drilled in the shell 110a, and FIG. 2 is a state diagram in which a hole is drilled in the shell 110b and vertically aligned with the alignment bar 113. As shown in FIG.

As shown in Figures 1 and 2, the shell alignment apparatus for vertical oyster culture according to an embodiment of the present invention is a base 111, an alignment bar 113, a drilling machine 115, a drill 117, It may include a fixing part 119 and a support part 121 .

The base 111 supports the device and functions as a frame in contact with the ground.

The alignment bar 113 has a straight vertical structure, and may be a pipe having an inner hole or an iron core without an inner hole, and may be made of a metal material or a plastic material.

The alignment bar 113 is a member in which the shells 110a and 110b with holes are sequentially aligned, and may have a straight rod structure or a lower end of a fallopian tube structure, and in the case of a fallopian tube form, a form of fastening the fallopian tube portion or A one-piece structure is possible.

The drilling machine 115 is located on the upper side, is a device capable of drilling a hole in the shell, and a drill 117 is mounted at the tip.

The drilling machine 115 or the drill 117 may move in the direction of the arrow in the direction ①.

The fixing part 119 serves to hold the shell 110a when drilling a hole in the shell 110a and may be formed on the outside of the drill 117 at least one, and may be operated in the direction of the arrow in the direction ②.

The support part 121 is a part on which the shell 110a is placed when a hole is drilled in the shell 110a, and is placed in a horizontal state before the shell hole is drilled as shown in FIG. Afterwards, it has a structure that opens left and right in the direction of the arrow in the direction of ③.

The opening structure of the support part 121 is only a preferred example, and any shape is irrelevant as long as the shell can be vertically dropped whether it is opened by horizontal rotation.

As the drill 117 goes down while drilling the shell, the tip of the drill 117 and the tip of the alignment bar 113 are aligned to the extent that they almost come into contact with each other, and the alignment bar 113 and the drill 117 are at the center line of each other. It is formed so as to lie on this straight line.

The reason is to create a structure in which when a hole is drilled in the shell by the drill 117, the shell is directly inserted into the alignment bar 113 during vertical fall to fall downward.

Looking at the operation, the shell 110a is placed on the support part 121 in the set state as in FIG. 1 , and the shell 110a is fixed by the fixing part 119 , the drilling machine 115 . And a hole is drilled in the center of the shell (110a) by the drill (117).

At the same time as the hole is drilled, as shown in FIG. 2, the support part 121 is opened left and right in the direction of the arrow in the ③ direction, and the shell 110a falls vertically while the hole is inserted in the alignment bar 113 and is sequentially aligned from the bottom. do.

When dozens of shells are sequentially drilled and stacked sequentially on the alignment rod 113, a set of shell alignment is made, and the alignment rod 113 in which the shells are aligned is moved to a process that can be mounted on the lower lip or , it can be properly loaded in the storage so that it can be mounted on the luggage compartment later.

The shells aligned by the vertical oyster culture alignment device of the present invention can be automatically mounted on the sagging edge by the alignment bar 113 itself, and examples thereof include the following.

Products in which shells are aligned by a vertical oyster culture alignment device as shown in FIGS. 1 and 2 are sequentially separated by using the shell hanging mechanism for oyster culture of Patent 10-1564080, which the applicant applied for and received a patent registration for. Automatic mounting is possible on the cradle.

3 to 5 are schematic views of a shell alignment device for horizontal oyster culture according to another embodiment of the present invention.

The horizontal type shell alignment apparatus for oyster culture of FIGS. 3 to 5 has the same basic principle as the vertical type shell alignment apparatus for oyster culture of FIGS. 1 and 2, only the shapes of the alignment bars 113 and 313 are different, The only difference is the way the shells move.

The horizontal shell alignment apparatus for oyster culture of the present invention may include a processing unit 310 , a moving unit 320 , a fixing unit 330 , and an alignment unit 340 .

The processing unit 310 has the same configuration as the shell alignment device for vertical oyster culture shown in FIGS. 1 and 2 and makes a hole in the shell by the same operation, drilling machine 315, drill 317, high It includes a top part 319 and a support part 321, and each configuration is the same as that of FIGS. 1 and 2 .

The moving unit 320 is used to move the shell, and in the case of the vertical type, there is no need for a separate moving device because the shell descends vertically, but in the case of the horizontal type, the shell moves from the left to the right of the drawing in a horizontal state. Because it has to be moved to the , a separate moving device is required.

The moving unit 320 includes a cylinder 311 , a horizontal fixing unit 325 , and a conveying unit 327 , and the horizontal fixing unit 325 and the conveying unit 327 are moved from left to right by the action of the cylinder.

The horizontal fixing part 325 is elastically moved by the cylinder 311 in a state supported by the spring 325b on the support plate 329 .

The elastically moved horizontal fixing unit 325 causes the tongs 325a to support the first alignment bar 313 .

By the action of the cylinder 311, the transfer unit 327 is moved from left to right, and while pushing the vertical fixing unit 330, the first alignment bar 313 is supported by the tongs 327a. will transfer

The horizontal fixing part 325 and the conveying part 327 are simultaneously moved from the left to the right by the cylinder 311, and the horizontal fixing part 325 is the first alignment bar 313 by the elasticity of the spring 325b. From this time, only the transfer unit 327 is moved from left to right when supporting.

The vertical fixing unit 330 is mounted on the first alignment bar 313 and is pushed down by the transfer unit 327 while being pushed down by a hinge fastened to one end in the downward direction.

As the vertical fixing unit 330 descends, the first alignment bar 313 is supported by the transfer unit 327 at the same time.

The alignment unit 340 is an alignment bar for aligning the shells, and may be divided into a first alignment bar 313 and a second alignment bar 313a.

The first alignment bar 313 may have a 'L' shape, and the second alignment bar 313a may have a vertical straight shape, and may be formed in a structure capable of being separated and fastened to each other.

The first alignment bar 313 is a structure capable of aligning the shells in a horizontal state, and the second alignment bar 313 is a vertical alignment structure having the same function as the alignment bar 113 of FIGS. 1 and 2 .

The second alignment bar 313a is a configuration that can be added as needed.

An operation process will be described with reference to FIGS. 3 to 5 .

As shown in FIG. 3 , the shell hole is drilled by the drilling machine 315 in a state where the shell 310a is positioned on the support part 321 and fixed by the fixing part 319 .

Next, as shown in FIG. 4 , when a hole in the shell is drilled (or at the same time it is drilled), the support part 321 is opened while being spread to both sides in the downward direction, and the shell falls to the first alignment bar 313 in the vertical direction.

Next, as shown in FIG. 5 , the cylinder 311 operates and the horizontal fixing unit 325 is fixed by mounting the first alignment bar 313 .

Simultaneously with the operation of the cylinder 311 , the vertical fixing unit 330 moves down in the direction of the arrow with respect to the hinge axis while pushing the vertical fixing unit 330 while the conveying unit 327 moves.

The vertical fixing part 330 goes down to horizontally move the shell.

The transfer unit 327 moves horizontally while lowering the vertical fixing unit 330 and at the same time supporting the first alignment bar 313 supported by the vertical fixing unit 330 by the tongs 327a as it is, and also the shell ( 310a) and horizontally moves the shell 310a from the left to the downward direction.

In this case, when the first alignment bar 313 is configured, a prevention portion is formed at the tip to prevent the shell 313a from falling out, so that the shells can be horizontally aligned in this state.

In addition, if the structure is connected to the second alignment bar 313a at the tip of the first alignment bar 313, the shells may be vertically descended to the second alignment bar 313a to be sequentially aligned from the bottom to the top.

After each shell is aligned with the first or second alignment rods 313 and 313a, the horizontal fixing unit 325, the conveying unit 327, and the vertical fixing unit 330 automatically by the return of the cylinder 311 are is relocated

In the case of alignment by the first alignment bar 313, a separate lower edge is connected to the front end of the first alignment bar 313, and after continuous movement, a shell hanger is mounted at a predetermined position, and then the shell is moved one by one. You can automatically complete a set of cultured shells.

In the case of alignment by the second alignment bar 313a, the available method is the same as the shell alignment apparatus for vertical oyster culture shown in FIGS. 1 and 2 .

Figure 6 is a schematic view of adding an automatic insertion device for maintaining the interval between shells to the shell alignment device for vertical oyster culture according to an embodiment of the present invention, Figure 7 is a vertical oyster culture according to an embodiment of the present invention It is a perspective view of the support part and the tube transfer insertion part applied to the dragon shell alignment device.

The symbol 120 shown in FIGS. 1 and 2 and the symbol 320 shown in FIGS. 3 to 5 are gangyun maintenance pipes.

The spacing tube (120, 320) is located between the shells in the horizontally or vertically aligned shells to maintain a certain distance between the shells.

The gap maintaining tubes 120 and 320 maintain a predetermined distance between the shells.

Oyster culture goes through a seedling process before culture, and the aligned shells into which the spacing tubes 120 and 320 are inserted are used during seeding.

Referring to FIG. 6 , although the vertical alignment device for oyster culture shown in FIGS. 1 and 2 is illustrated as an example, the same may be applied to the horizontal type alignment device for oyster culture of FIGS. 3 to 5 .

A tube transport insert 523 is added to the alignment device of FIGS. 1 and 2 .

The tube transfer insertion part 523 is hinge-coupled at one end and rotates in the forward direction of the drawing, rotates while inserting the gap maintaining tube 520 and moves when the shell falls and is positioned above the alignment bar 513 to space The holding tube 520 is dropped.

From the bottom of the alignment bar (513), the shell → spacer tube → shell → spacer tube is aligned in the order.

Referring to Figure 7, while explaining the structure of the support portion 521 and the tube transfer insertion portion 523, the operation will be described in detail.

(A) is a state diagram of the pipe transport insertion unit 523 in its original position, (B) is a state diagram of a position in which the pipe transport insertion unit 525 can vertically drop the spacing maintaining tube 520 to the alignment bar 513 to be.

The support part 521 has a body 721 forming a tube insertion hole 717 in the center, and legs 719 spread out in all directions from the corners of the body 721 are formed, and between the legs 719 on the front side. A guide 715 is formed in the tube insertion hole 717, and the left and right first support portions 521a and second support portions 521b are formed on the basis of the tube insertion hole 717.

The tube transfer insertion part 523 has a T-shape, and one end is hinged by a hinge part 711 and can be rotated in the direction of the arrow.

The tube transfer insertion portion 523 is formed with a tube seating portion 713 of a circular hole on the other end side of the hinge portion 711 .

The tube seating portion 713 is rotated so that the center point coincides with the tube insertion hole 717 of the support portion 521 .

First, at the same position as (A), the gap maintaining pipe 520 is seated one by one by a separate pipe loading device (not shown) on the pipe seating part 713 . At this time, the spacing tube 520 is set in the tube seating portion 713 without falling downward by the guide 715 .

Thereafter, it rotates in the direction of the arrow, and at this time, the gap maintaining tube 520 moves in contact with the guide 715 , so the tube transfer insertion unit 523 rotates without falling.

When the tube transfer insertion unit 523 rotates and the center point of the tube seat portion 713 and the tube insertion hole 717 coincides with each other, the gap maintaining tube 520 does not have a supporting part on the lower surface, so it falls freely. .

During free fall, the alignment bar 513 is positioned on the lower side of the support part 521 , so that the spacing tube 520 is fitted to the alignment bar 513 .

Look at the configuration in which the shell 510 and the spacing tube 520 are sequentially and alternately aligned.

The shell 510 is drilled by a drilling machine, and the support part 521 is opened and the shell 510 falls while being inserted into the alignment bar 513 .

After that, the support portion 521 is closed and the tube transfer insertion portion 523 on which the spacing maintaining tube 520 is seated rotates while the center of the tube seating portion 713 and the tube insertion hole 717 is aligned with the spacing maintaining tube ( 520 falls while being fitted to the alignment bar 513 .

As this process is repeated, the shell 510 and the spacing tube 520 can be alternately aligned.

3 to 5 are alternately aligned in the same manner in the horizontal type shell alignment apparatus for oyster culture, and simultaneous horizontal movement of the shell and the spacing tube by the transfer unit 327 is possible when the position in the horizontal line is moved.

Although the present invention as described in detail above has been described based on limited embodiments and drawings, the present invention is not limited thereto, and the present invention is described by those skilled in the art to which the present invention pertains. Various modifications and variations are possible within the spirit and equivalent scope of the claims.

However, it is clear that such simple modifications and variations cannot depart from the scope of the present invention.

111, 511: base 113, 313, 313a, 513: alignment bar
115, 315, 515: drilling machine 117, 317, 517: drill
119, 319, 519: fixed part 120, 320, 520: gap maintaining pipe
121, 321, 521: support part 310: processing part
311: cylinder 320: moving part
325: horizontal fixing part 327: transfer part
330: vertical fixing part 340: alignment part
523: tube transfer insertion portion 711: hinge portion
713: tube seat 715: guide
717: tube insertion hole

Claims (9)

a drilling machine including a drill for drilling a hole in the shell vertically in the upper direction of the shell placed at a predetermined position;
a support part on which the shell is placed before the shell's hole is drilled, and rotates in one direction when the shell's hole is drilled by the drilling machine so that the shell falls down;
The drill and the center line coincide with the alignment bar, which is located below the support part, and is sequentially aligned with the perforated shells threaded therein;
The alignment bar is in the form of a 'b' in which a vertical part and a horizontal part are combined,
A vertical fixing part for supporting the horizontal part is further formed,
The vertical fixing unit is hinged to one end and rotates, a shell alignment device for oyster culture. According to claim 1,
The support part consists of a pair of left and right symmetrical structures,
Each of the support parts abuts each other in a horizontal state to form a support shape, and is hinged at both ends to rotate in the opposite downward direction and open, an oyster shell alignment device. According to claim 1,
The drill is movable in a downward direction,
At the time of drilling the hole of the shell, the tip of the drill and the tip of the alignment bar are spaced apart from each other at a predetermined distance so that the shell does not separate, a shell alignment device for oyster culture. According to claim 1,
The alignment bar is a straight or 'L' shape, a pipe type or an iron core type without an inner diameter, a shell alignment device for oyster culture. According to claim 1,
When a hole is drilled in the shell, a fixing part operated in the vertical direction to hold the periphery of the shell is further formed, a shell alignment device for oyster culture. According to claim 1,
On one side of the alignment bar, a transfer unit for moving the shell located in the horizontal portion in the other direction by horizontal movement by a cylinder is further formed, an oyster shell alignment device. 7. The method of claim 6,
A shell alignment device for oyster culture that is further formed with a horizontal fixing unit for supporting the bent portion of the alignment bar by moving horizontally with the conveying unit by the cylinder. a drilling machine including a drill for drilling a hole in the shell vertically in the upper direction of the shell placed at a predetermined position;
a support part on which the shell is placed before the shell's hole is drilled, and rotates in one direction when the shell's hole is drilled by the drilling machine so that the shell falls down;
The drill and the center line coincide with the alignment bar, which is located below the support part, and is sequentially aligned with the perforated shells threaded therein;
Further comprising a pipe transfer insertion part which is hinged at one end to the upper side of the support and rotates,
The tube transfer inserting unit is inserted so as to be alternately aligned with the shell by transferring the spacing maintaining tube for maintaining the spacing between the shells aligned to the alignment bar, shell alignment device for oyster culture. 9. The method of claim 8,
A tube insertion hole is formed in the center of the support part, and a guide is formed in the horizontal direction in front,
The tube transfer insert is formed with a tube seat,
The tube seat portion coincides with the center point of the tube insertion hole by rotation, a shell alignment device for oyster culture.

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