Note: Descriptions are shown in the official language in which they were submitted.
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TITLE: ASSEMBLY FOR HARVESTING SHELLFISH SUCH AS SCALLOPS AND
ALIKE
1. BACKGROUND OF THE INVENTION
1. Definition of the Invention
The present invention refers, in general, to apparatuses for harvesting
shellfish and, more
particularly, to an assembly for harvesting shellfish such as scallops and
alike.
2. Description of the State of Art
As a rule, shellfish living on or in the sea bottom are harvested with the aid
of draggers or the
like which are dragged along the sea bottom. Such draggers or the like are
provided with tines or
knives reaching into the bottom, such that the tines or knives are pulled
through the sea bottom.
Ajet of water is directed to the sea bottom, so that the soil of the sea
bottom is stirred up and
raised. As a result, a quantity of shellfish is disengaged. Behind the tines
or the knives, in the
dragger, a collecting basket is located in which the shellfish is caught,
while mud, sand,
sediment, undersized shellfish and the like can flow back through the basket.
As a result of the
water injection and the direction of the latter, a relatively large mass of
sediment is flushed from
the bottom. The fact that as a result of on the one hand, the pulling force
applied to the dragger
and, on the other hand, the force of the water jet directed approximately
vertically during the
harvesting operation, a buoyant force is applied to the dragger which must be
compensated by
the weight of the dragger.
Thus, one can conclude, that the known methods of harvesting shellfish suffer
the problem of
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severely disturbing or destroying the shellfish beds. Such destruction of
shellfish beds limits the
ability of the latter to regenerate themselves, thus reducing the quantity of
shellfish available for
harvesting in the future.
Various attempts have been made to solve or at least to mitigate the negative
aspects of the
existing shellfish harvesting. Some attempts can be exemplified in the
following prior art
references: U.S. Patent Application Publication No. 2006/0037550 to May et al.
published Feb.
23, 2006 with the title "Apparatus and method of harvesting shellfish"
describes an assembly
comprising a boom positioned with one end over the deck of the boat and
attached with another
end to a turret, and a gathering device. The latter has a rake with a
plurality of spaced apart
prongs to entrap shellfish. The rake contains also a spray bar with a
plurality of spray ports. A
hydraulic cylinder is mounted on the boom, while another hydraulic cylinder is
mounted to a
gathering arm. The foregoing apparatus has several important disadvantages,
among which are:
the depth of harvesting is limited by the length of the gathering arm and the
use of hydraulic
cylinders renders the apparatus relatively expensive and less reliable.
Another example is: U.S.
Pat. No. 5,027,533 to Holt et al. issued Jul. 2, 1991 for a "Vibratory
shellfish harvesters and
methods". Basically, a Holt's harvester includes a sledge having a pair of
runners designated to
slide over the submarine surface of a shellfish growing substrate and a
plurality of tines
extending downward from the sledge for penetration into the substrate. A
vibratory device is
used to impart a vibratory motion to those tines, in a substantially normal
direction to to the
submarine surface. The vibratory device includes a rotatable, off-center mass
and a hydraulic
motor for rotating the mass; a shock absorber device is used to reduce
vibration of the runners by
the vibratory device. The solution described in this patent is an example of
substrate disturbance
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by the plurality of tines. Moreover, the use of a vibratory device negatively
affects the submarine
interface between bottom sediment and the water just above it, which is a very
important region
of submarine water.
II. SUMMARY OF THE INVENTION
Based on the above presentation, it will become apparent that the forthcoming
objectives of the
present invention are not accomplished by presently available apparatuses.
Accordingly, a basic objective of the present invention is to design an
assembly which minimize
undesirable habitat damage by reducing the disruption of the beds in which
remaining shellfish
continue to grow.
Another important objective is to obtain dynamic fluid forces able to extract
shellfish and divert
it into a subassembly for collecting and discharging.
Broadly stating the assembly for harvesting shellfish such as scallops and
alike, according to the
present invention, comprises
a frame-enclosure truss subassembly to which are attached
an internal subassembly for directing a flow of encountered water during a
dragging
operation of the assembly for harvesting shellfish;
a subassembly for collecting and discharging harvested shellfish; and
an external subassembly for encasing the frame-enclosure truss subassembly
together with
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the internal subassembly for directing a flow of encounter water during a
dragging.
The frame-enclosure truss subassembly includes a pair of lateral trusses
extending longitudinally
and spaced at a distance commensurable with a working width of the assembly
for harvesting
shellfish.
The internal subassembly for directing a flow of encountered water during a
dragging operation
includes an anterior, curved panel having its concavity forwards oriented and
a posterior, curved
panel having its concavity backwards oriented. The anterior and posterior
curved panels are
flanked by the pair of lateral trusses.
The subassembly for collecting and discharging harvested shellfish, disposed
behind the internal
subassembly for directing a flow of encountered water during a dragging
operation, includes a
louver type grille-platform, a metal grid receptacle supported by the louver
type grille-platform
and a mechanism for topple over the metal grid receptacle when loaded with
shellfish.
At least a pair of sets of a multiplicity of hinged flexible flaps is used, a
first, front one being
attached to a lowest part of the internal subassembly for directing a flow of
encountered water
during a dragging operation, where the anterior and posterior curved panels
meet, while a second
multiplicity of hinged flexible flaps is attached at a frontal part of
thelouver type grille-platform.
III. BRIEF DESCRIPTION OF THE DRAWINGS
Although the characteristic features of the invention will be particularly
pointed out in the
claims, the invention itself and the manner in which it may be made and used
may be better
understood by referring to the following description and accompanying
drawings, where like
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reference numerals refer to like parts throughout the several views of the
drawings, in which:
FIGURE 1 is a perspective view of the assembly for harvesting shellfish such
as scallops and
alike;
FIGURE 2 shows an exploded view of the assembly depicted in FIG. 1;
FIGURE 3 is a top plan view of the assembly depicted in FIG. 1;
FIGURE 4 is a longitudinal cross section taken along line X1-X1, depicted in
perspective, of
FIG. 3;
FIGURE 5 is a longitudinal cross section taken along line X1-X1 of FIG. 3;
FIGURE 6 is a perspective view of a frame-enclosure truss subassembly;
FIGURE 7 is an enlarged fragmentary perspective view of "DETAIL A" depicted in
FIG. 2;
FIGURE 8 is an exploded view of a louver type grille-platform according to the
present
invention;
FIGURE 9 is an enlarged fragmentary view of "DETAIL C" depicted in FIG. 8;
FIGURE 10 is a perspective view of a mechanism for topple over a loaded metal
grid receptacle;
FIGURE 11 is an enlarged fragmentary view of "DETAIL B" depicted in FIG. 2;
FIGURE 12 is an exploded view of a flat panel; and
FIGURE 13 is a longitudinal cross section as shown in FIG. 5, wherein the flow
of water and
shellfish is diagrammatically shown.
IV. DESCRIPTON OF THE PREFERRED EMBODIMENT
The accompanying drawings, as above described, illustrate a preferred
embodiment of an
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assembly for harvesting shellfish such as scallops and alike, generally
referenced as 10. For
convenience, in the following disclosure, the foregoing assembly will be named
"assembly 10".
As a caveat, it is to be agreed, that terms, such as "top", "bottom", "front",
"back", "vertical",
"horizontal", "upward", "downward" and "outward" are conventionally employed
in the present
specification with reference to the normal position in which assembly 10 will
be used.
Broadly describing, with reference to FIGURES 1 through 5, assembly 10
comprises a frame-
enclosure truss subassembly 100, to which are attached other subassemblies
which compose
assembly 10, namely:
an internal subassembly 200 for directing a flow of encountered water during a
dragging of
assembly 10, when the latter is immersed; and
a subassembly 300 for collecting and discharging harvested shellfish; and
an external subassembly 400 for encasing frame-enclosure truss subassembly 100
together
with internal subassembly 200 and subassembly 300 for collecting and
discharging harvested
shellfish.
Describing now in detail, frame-enclosure truss subassembly 100 (see FIGURE
6), which is a
space truss of welding design, includes:
a tubular member 105 frontally located and transversally extending with
respect to assembly
10; tubular member 105 has a length generally commensurable with a working
width of the
aforementioned assembly 10;
a pair of lateral trusses 110 extending backward from tubular member 105,
namely from
longitudinal extremities of the latter; each lateral truss 110 is made of
standard L-section
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beams and incorporates an inclined upper truss member 115 starting from
tubular member
105, to which it is permanently secured, and extending upwardly; an
intermediary upper
truss member 120 forms a butt joint with inclined upper truss member 115 and
extends
backward, slightly deviating upwardly from the horizontal direction; an upper
end truss
member 125, which after forming a butt joint with intermediary upper truss
member 120
extends backward, slightly deviating downwardly from the horizontal direction;
each lateral truss 110 further incorporates a lower truss member 130,
characterized by a
contour similar to a longitudinally stretched S, which starts from tubular
member 105, to
which it is permanently secured, and extends backward and downwards; lower
truss
member 130 has a length, when projected on a horizontal plane, generally
similar to
compounded lengths, when projected on a horizontal plane, of inclined upper
truss member
115 and intermediary upper truss member 120;
each lateral truss 110 yet further includes: a) a vertical strut 135 which
starts from
intermediary upper truss member 120, more precisely, starts in proximity of
the zone where
intermediary upper truss member 120 forms a butt joint with inclined upper
truss member
115, and joins lower truss member 130; b) an inclined strut 140 which extends
from a
bottom of vertical strut 135 and ends, after contacting an upper end of lower
truss member
130, in a vertical imaginary plan which passes through an end surface of lower
truss
member 130; and c) a connecting truss member 145 which joins a lower terminal
zone of
upper end truss member 125 and an upper terminal zone of lower truss member
130;
connecting truss member 145 has a profile similar to an arc of a circle
subtending an angle
somewhat more than 90 ; a top segment of connecting truss member 145 departs
upwards
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from its normal circular contour;
finally, each lateral truss 110 is also provided with a diagonal type strut
150 which generally
joins a middle zone of intermediary upper truss member 120 with a middle zone
of
connecting truss member 145;
in order to secure a spatial rigidity of frame-enclosure truss subassembly
100, the pair of
lateral trusses 110 are interconnected as follows:
by 1) aforementioned tubular member 105;
2) a first flat bar 155 so joining the underneaths of vertical struts 135 as
to coincide
with a segment of a lower external contour of lower truss member 130;
3) a second flat bar 160 joining inclined strut 140 with lower truss member
130 in a
zone where inclined strut 140, after contacting an upper end of lower truss
member 130, ends in a vertical imaginary plane which passes through an end
surface of lower truss member 130;
4) an inversed L-beam 165 which captures and joins connecting truss member
145,
respectively its upper part, and lower terminal zone of upper end truss member
125, where the former and the latter form a junction.
Inclined upper truss member 115, intermediary upper truss member 120, upper
end truss
member 125, lower truss member 130 and connecting truss member 145, all made
of
standard L-section beams, have all their laterally oriented legs traversed
along their length
by a plurality of equally spaced apertures 170 whose use will be described
further in this
disclosure; second flat bar 160 is longitudinally provided with equally spaced
openings 175
and their use will be explained in the forthcoming disclosure.
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A first set of a multiplicity of hinged flexible flaps 180, made of rubber or
equivalent
materials, is secured along second flat bar 160 via conventional fasteners
such as bolts 185
inserted into equally spaced openings 175 and tightened by nuts 190.
Internal subassembly 200 includes basically an anterior, curved panel 205 with
its concavity
forwards oriented, followed by a posterior, curved panel 210 with its
concavity backwards
oriented.
Anterior, curved panel 205 starts from tubular member 105 to which it is
secured,
then extends downwards and backwards, being continuously superimposed on and
secured
to:
lower truss member 130, respectively its lower external surface;
bottom of first flat bar 155; and
bottom of second flat bar 160.
Posterior, curved panel 210 is so profiled as to coincide with connecting
truss member
145, on which is superposed and to which is attached.
Subassembly 300 adapted for collecting and discharging harvested shellfish,
such as scallop and
alike includes:
A) a louver type grille-platform 302;
B) a metal grid receptacle 304 supported by louver type grille-platform 302;
C) a mechanism for topple over 306 a loaded metal grid receptacle 304; and
D) a second and a third set of a multiplicity of hinged flexible flaps,
respectively 308 and
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309, secured to louver type grille-platform 302.
Louver type grille-platform 302 (see FIGS. 8 and 9) is spaced behind a lower
part of curved
panel 210 and incorporates a first grille section 310, followed by a second
grille section
312, both being horizontally positioned and having the same width, generally
commensurate with the working width of assembly 10. A gap G is provided
between first
and second grille sections 310 and 312.
First grille section 310 comprises a frontal L-section beam 314 provided at
each end with a
pair of hinge brackets 316 having coincidental eyelets. Frontal L-section beam
314 is
traversed along its length by a series of bolt-holes 318.
A strip 320 is placed oppositely frontal L-section beam 314 and spaced at a
relatively
small distance from the latter. The former is traversed along its length by a
plurality of
bolt-openings 322. Frontal L-section beam 314 and strip 320 are rigidly
secured together,
at their ends, in order to form a rectangular frame, by a pair of L- section
segments 324.
Each L-section segment 324 has a cut-out for adjusting to frontal L-section
beam and also a
lateral perforation 326. A plurality of vertical spacers 328 is placed at
equal intervals
between frontal L-section beam 314 and strip 320.
Second grille section 312, as viewed in plan, has also a rectangular shape and
includes an
anterior L-section beam 330 and a posterior inversed L-section beam 332, the
latter,
positionally, constituting a mirror image of the former. Anterior L-section
beam 330 is
traversed along its length by a plurality of bolt-openings 332 coincidental
with those of
strip 320.
A pair of elongated flat plates 334, each provided at each end with a cut-out
for engaging an
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adjacent leg at the extremities of anterior L-section beam 330 and posterior
inversed L-
section beam 332, is used. Each elongated flat plate 334 of the aforementioned
pair is
provided along its length with a plurality of equally spaced apertures 170,
similar with
those used in the pair of lateral trusses 110.
Several elongated flat plates 334', distinguishable from the pair of elongated
flat plates 334
only by the fact that the plurality of equally spaced apertures 170 is
missing, are placed
parallel to the pair of elongated flat plates 334 and equally spaced among
themselves.
Several sloping boards 336, located in the same plan with the several
elongated flat plates
334', are perpendicularly disposed relatively to the later, and form together
a series of
chutes 338.
Metal grid receptacle 304 is parallelepiped-shaped, made of grading screen,
and open only
in the front. It is obvious, that metal grid receptacle 304 can be changed for
another screen
having a different mesh size to suit specific species of the selfish to be
harvested.
Mechanism for topple over 306 comprises a pair of polygonal structures 340,
laterally and
vertically located as to sidewise engage metal grid receptacle 304. Each
polygonal structure
340 has four sides a. A pair of sides a converge and intersect frontally
forming an acute
angle, an opposed pair of sides a define an obtuse angle, while the remaining
angles are
right angles. Each zone of convergence of a pair of sides a corresponding to
the acute
angle is provided with a hole b. Four transversal elongated bars 342 connect
between them
the pair polygonal structures 340, namely between each intersection of a pair
of sides a.
Starting from a bottom of each polygonal structure 340, three rigidity bars
344 are used to
secure, at their midway, two successive transversal elongated bars 342.
Transversal elongate
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bar 342, adjacent hole b is somewhat backwards retracted from an apex of the
intersection of the corresponding pair of sides a. Rigidity bar 344 that is
located at the
bottom of polygonal structure will always be placed beneath metal grid
receptacle 304
A first tilt lever 346, disposed in a vertical plan and inclined with respect
to a horizontal
plan, is attached at the middle of an upper transversal elongated bar 342. To
enhance the
reliability of the attachment of the forrner with respect to the latter from
both sides, a pair of
side reinforcing gussets 348 is used. First tilt lever 346 is provided, at its
front side, with
an opening c. A second tilt lever 350, forwards directed, follows first tilt
lever 346. Second
tilt lever 350 includes at its back end a double-bracket hinge 352 traversed
by an opening
c. Double-bracket hinge 352 receives front side of first tilt lever 346 and a
conventional
pin is used to articulate first and second tilt levers 346 and 350. A hooking
bracket 354
used for lifting is secured at the upper back end of second tilt lever 350. A
rod 356 is
perpendicularly attached at that end of second tilt lever 350 that is opposite
located with
respect to double-bracket hinge 352. Each end of rod 356 is, by insertion,
lodged as a
bearing journal into a sleeve 358. Both sleeves are secured to inversed L-beam
165
incorporated in frame-enclosure truss subassembly 100. To enhance the
reliability of an
attachment of a front end of second tilt lever 350 to rod 356, a pair of side
reinforcing
gussets 348 is used.
Second set of a multiplicity of hinged flexible flaps, see reference number
308, is formed
as a succession of longitudinally overlapping flaps that extend downwardly
closer to the
seabed (in comparison with first set of a multiplicity of hinged flexible
flaps 180). A front
strap 360 provided with a series of holes coincidental with the series of bolt-
holes 318 of
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frontal L- section beam 314 and a corresponding multiplicity of conventional
fasteners,
such as bolts 185 inserted into equally spaced bolt-holes 318 and tightened by
nuts 190.
Third set of a multiplicity of hinged flexible flaps (an optional set intended
for large rocky
bottoms), see reference number 309, is inserted into gap G formed between
strip 320 of
first grille section 310 and anterior L-section beam 330 of second grille
section 312. Since
anterior L-section beam 330 is traversed along its length by a plurality of
bolt-openings
332 coincidental with those of strip 320, for attaching the multiplicity of
hinged flexible
flaps, use is made of bolts 185 and nuts 190 as in previous flaps attachments.
Third set of a multiplicity of hinged flexible flaps 309 is relatively shorter
than first set of a
multiplicity of hinged flexible flaps 180.
External subassembly 400 for encasing frame-enclosure truss subassembly 100
together
with internal subassembly 200, and, as well, subassembly 300 for collecting
and
discharging harvested shellfish,, comprises:
A pair of vertical, sturdy, lateral walls 402 extending longitudinally for
flanking encasing
frame-enclosure truss subassembly 100 and the other subassembly attached to
it. A foil F is
also flanked by the pair of vertical, sturdy, lateral walls 402, being located
transversally
to the latter, and generally, corresponding to a center of a cavity formed in
the front of
internal subassembly 200.
At its uppermost part, each vertical, sturdy, lateral wall 402 is defined by
an upper
periphery, which, basically, reproduce a continuous corresponding successively
to a top of
inclined upper truss member 115 starting from tubular member 105, to a top of
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intermediary upper truss member, to a a top of upper end truss member 125,
and, then,
after abruptly descending, to a top of L-section segment 324 and, finally, to
a top of
elongated flat plate 334.
A lower contour of each vertical, sturdy, lateral wa11402 starts from tubular
member 105
and continues with a curvilinear descent that forms, as seen from outside, a
convex shape,
to change into a horizontal line extending up to an end of assembly 10.
A sole 404, made from a flat bar, is secured to a bottom of and outwardly from
each
vertical, sturdy, lateral wal1402, namely through the length of its lower
contour. Several
spaced stiffeners 405 are used to enhance a reliability of the joint between
each vertical,
sturdy, lateral wal1402 and sole 404. A runner 406 having a profile
reproducing sole 404 is
removably attachable to the latter. Sole 404 and runner 406 are each provided
with
coinciding openings 408 which via bolt-nut connections 410 allow their
attachment.
There is a distance between a lowest point of anterior, curved pane1205 of
internal
subassembly 200 and a bottom of each runner 406 which touches the submarine
surface. In
a space created by that distance extend downwardly first, second and third
sets of multiple
hinged, flexible flaps, respectively 180, 308 and 309.
A unit of several eyelet hooks 412 for dragging and lifting is firmly secured
laterally to an
external surface of each vertical, sturdy, lateral wall 402.
Each of the latter is traversed by a number of perforations as follows:
perforation s for lateral truss 110 attachment; perforations s being coaxial
with the plurality
of equally spaced apertures 170 drilled into inclined upper truss member 115,
intermediary
upper truss member 120, upper end truss member 125, lower truss member 130,
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connecting truss member 145, and elongated flat plate 334; a perforation s is
also
compatible with lateral perforation 326 in L-section 324;
perforations t for locating and positionally adjusting foil F; one perforation
t for locating
foil F and three perforations t spaced backwards and disposed on an arc of a
circle; and a
pair of screws u for passing through two of the foregoing four apertures t and
for tightening
in threaded blind holes v provided at each lateral extremity of foil F; and
a discharge perforation x for air escape from a space in front of anterior,
curved panel 205.
An inclined top panel 414 starting from tubular member 105 extends backwards
along and
over a pair of inclined upper truss member 115. Inclined top pane1414 is
secured to the
pair of inclined upper truss members 115. An intermediary top pane1416
starting from a
back end of inclined top pane1414 extends also backwards along and over a pair
of
intermediary upper truss members 120. Intermediary top panel 416 is secured to
the pair
of intermediary upper truss members 120.
A flap panel 418 (set of 4) starting from an end of inclined top panel 414
extends, in general,
backwards, along and over a pair of upper end truss members 125. Flap pane1418
has a
rectangular shape and includes a plate 420 reinforced along its sides by
straps 422. A front
transversal edge 424 of plate 420 extends forwards beyond its adjacent strap
422 to lay on a
L-section deformable beam 426 secured at a beginning of the pair of upper end
truss
members 125. Plate 420 and straps 422 are provided with corresponding orifices
428 and
bolt-screw combinations 430 for joining together.
An extra strap 432 is superimposed on front transversal edge 424. The former
and the latter
are also provided with corresponding orifices 428 and bolt-screw combinations
430 for
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joining together.
A deformable strap 432 is attached on top of inversed L-beam 165 and is
intended to
alleviate impacts from an opposed posterior part of flap panel 418 when the
latter is
brusquely closing.
OPERATION
The present assembly 10 is attached by a cable to a floating vessel and
dragged over the sea
bottom. A hoisting mechanism (not shown), operating the cable, is attached to
the floating vessel
and is used to lower assembly 10 on the sea bottom before any dragging
operation starts and to
lift assembly 10 out of the water at an end of each harvesting operation. The
unit of several
eyelet hooks 412 for dragging and lifting is firmly secured laterally to an
external surface of each
vertical, sturdy, lateral wa11402 and is attachable by cable to the hoisting
mechanism atached to
the floating vessel.
Foil F, whose structure and attachment were disclosed before, provides a
surface designated to
maximize a force generated perpendicular to the water flow, i.e. a "lift",
while minimizing the
resistance under the water due to a friction of runners with the sea bed, i.e.
a "drag". Foil F is
provided with means for adjusting its attack angle by tilting in a fixed
position. An explanation
of the foil use is that the water flowing over foil F achieves a higher
velocity and a corresponding
lower pressure than the water flowing under foil F resulting in an upward
force /lift/; however,
due this pressure differential, the water near foil F tip tends to flow from
beneath foil F to above
the latter. This "leakage" around the tip forms foil tip vortices. When the
upper and lower water
flows meet at the trailing edge of foil F numerous little vortices are formed
and, then, unite to
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form a large vortex (at the tip of foil F).
This large vortex creates a spiral motion of water within a limited area,
namely a whirling mass
of water that sucks everything near it towards its center. Here intervenes
internal subassembly
200 with its anterior, curved panel 205 followed by posterior, curved panel
210. Thus, water
containing shellfish is carried away and then directed into metal grid
receptacle 304 via its open
front. Now the water can flow out of metal grid receptacle 304, while
shellfish is captured
therein.
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