Note: Descriptions are shown in the official language in which they were submitted.
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B~CKGROU~p OF T~IE INVEWTION
The p~esent invention relates to imeroved plastic
coated metal wire mesh undeLwater traps for marine life and a
method of ~aking same. More particularly the present invention
Lelates to undecwatèr traps such as lobster traps.
Conventionally, metal wire mesh underwater traps such
as ]obster traps are made by cutting appropriate ~ire portions
from a roll of coated wiLe mesh (such as plastic coated steel
wiLe mesh), forming such portions into the desired shapes, for
example, for the body, end~ and bridge tif a lobster tra~ is
being manuactured), clieping these portions in theiL proper
relative locations either by bending free ends of the wire mesh
of one portion over the wires of the mesh of an adjacent
portion OL by using metal clies to clip together adjacent
eortions, and then forming the aeproeriate oeenings, installing
the gate or door to the trae, and, in the case of a lobster
trae, installing the side (or kitchen) heads and earlor heads
which guide the lobster entering the trap body ancl erevent it
e~om escaeing thereerom. ~t eresent all wire mesh sold for
lobster trap productlon is p.v.c. coated.
While lobster traps manufactured acco~ding to such
conventional methods are currently very eopular, they suffer
Geveral serious drawhacks. Firstly, the ends of the wire mesh
eortions making ue the main body of the trap Oe necessity have
metal (steel) exposed to the environment. This results in such
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traps tending to coLeode relatively quickly because of the
coLLosive, undeLwater envilonment to which they are exposed.
~lso these exposed encls tend to cut clothing and gloves. As
well, when adjacent coated wire mesh portions are clamped
togetheL with metal (e.cJ. aluminium~ clies, the clips o-ften cut
the plastic coating eY~posing more of the metal wi~e of the ;nesh
to cotrosion and thus ceducing trap life. If, instead of
clamps, the ends of the wires of the mesh aLe folded over
adjacent E)octions of wiLe mesh to secure the two adjacent
eortions in place, the radical bend being ae~lied to the ends
Oe the wires causes the coating to stretch and thin out on the
outside edcJe o the curve that is being formed. This reduction
in thickness reduces the ability of the coating to withstand
scuffing and abrasions. Since the outside edges and corners of
the trap are the areas which would sustain the most damage in
use, and it is these outside edges and corners of the trap
where such Ladical bends are required, the conventional method
of clameing tends to put the least amount of coating on the
most ctitical and abused points of the trap.
It is an object of the present invention to erovide an
improved plastic coated metal wire mesh underwater trap for
marine life which avoids oc reduces many of the eroblems of
tcaLs made acco~dincJ to such conventional -techniques, and to
~rovide a method of making such improved traes.
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SUMMA~ OF THE IW ~NTIO~
According to the present invention there is provided a
method of makin~ plastic coated metal wire mesh underwater
traps for marine life, such as lobster traps. The method
comprises forming wire portions of the trap from uncoated metal
wire mesh and securing together these portions to assemble them
in proper locations to form the main body of the trap. The
assembled ~ire portions of the trap are then coated to
completely encase the wire thereof with plastic so that the
structural capacity of the plastic coating enhances that of the
secured together metal wire mesh portions of the trap.
In a preferred embodiment of the present invention,
the assembled wire portions of the trap are coated by means of
an electrostatic airless spray coating process. When the
coating step is completed, it is preferred that the trap be
subjected to a heatin~ step to set and bond the plastic to the
metal.
The invention further comerises traps made accordin~
to this process.
Traps such as lobster traps made in accordance with
the present invention have severaL advantages over pLastic
coated metal wire mesh traps made according to conventional
methods~ Firstly, because the coatin~ of the wire mesh takes
place after the wire portions of the trap have been assembled,
there is no exposure of raw metal on wire ends to the
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corrosive, saline, underwater environment. Thus, traps
manufactured according to the method of the present invention
have increased trap life. ~s well, the use of the
electrostatic airless spray pLocess to coat the metal wire mesh
according to the present invention enables a relatively uniform
thickness of coating on all parts of the wire mesh including on
outside edges and corners of the trap where ands of wirQs may
have been bent over to secure and place adjacent portions of
wire mesh.
Thirdly, and perha~s most importantly, because the
wire mesh is coated after construction of the main body of the
trap, the structural capacity of the coating material is used
in combination with that of the metal of the mesh and, where
used, metal clies or clamps, to enhance the stLuctural rigidity
of the trap which is fo~med according to the method oE the
present in~ention. In the past, because wire mesh in all
instances was coated prior to the construction of the trap,
this important structural potential of the coating material was
lost. The coating for its intended application, lobster trap
or otherwise, was simply to protect the mesh and no structural
capaci~:y was attributed to it. In the method according to the
present invention, a synergist;c increase in the strength and
structural integrity o~ the trap results when the wice edges,
which aLe secured together by clamping or otherwise, are then
coated. As the coating hardens o~er any two parallel wires
secured together, it fuses them together adding eurther
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strength and stopping the chaffing which would othecwise oceur
while the trap was in use. Thus, the strength and life
expectancy of the trap are greatly increased without increasing
its land weight or increasing the gauge of wire used or the
overall cost of the material in the trap. In other words,
while altering the traditional technology by changing the order
of the procedures by which the trap is made, a stronger and
longer-lasting product in accordance with the present inventio~
has suprisingly resulted.
BRIEF DESCRIPTION OF T~E DRAWINGS
These and other objects and advantages of the
invention will become apparent upon reading the following
detailed description and upon referring to the drawings in
which:
E'IGURE l is a schematic, perspective view of a plastic
coated metal wire mesh underwatec lobster trap o~ the type to
which the present invention is diceeted; and
E'IGURE 2 is an enlarged, partial view in perspective
of elipped together adjacent portions of a wire mesh lobster
trap manufactured according to conventional methods; and
F'L~URE 3 i6 an enlarged, partial view in perspective
of clipped together adjacent portions of a wire mesh lobster
trap manu~actured according to the method of the present
invention.
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While the invention will be described ln conjunction
with an example embodiment, it will be understood that it is
not intended to limit the invention to such embodimerlt. On ~he
contrary, it is intended to cover all alternatives,
modifications and equivalents as may be included within the
spirit and scope of the invention as defined by the appended
claims. For example, in this regard, the method and product of
the present invention, while described particularly with
respect to lobster traps, may be equally well applied to
shrimp, crab and eel traps, and the like.
DETAILED DESCRIPTION OF THE INVENTION
Turning to the drawinys, there is illustrated a
plastic coated steel wire mesh lobster trap, of conventional
shape, to which the method of the present invention is
particularly well-suited. The trap 2 comprises a body ~ having
a base 6 and sides ~ formed Prom a single rectangular strip of
pLefe~ably galvanized steel wire mesh. To body ~ are secured,
by me~ns of clips 10 (F'IGU~E 2) or by bencling ends of wire over
adjacent portions are end postions 12 and bridge portion l~.
Appropriate holes are cut in sides B ~or conventional kitchen
(or side) heads 16 and parlor heads l~. A pivoting door 20 is
fastened to a portion o~ body g to cover the opening over which
bridge lg extends on the side of body g opposite ba6e 6.
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Many of the problems with conventional construction oE
SUC~I traps, in which the wire mesh portions of the trap are
formed from plastic coated mesh are illustrated in FIGU~E 2.
Clips 10, for example holding end 12 to side ~, can bite into
the plastic coating of the wire mesh to cut the coating and
thus reduce trap life. WheLe ends of wire of mesh from end
portion 12 are bent over the wire of adjacent base 6, -the
coating of the mesh on the bends will be understood to be
thinned on the outer sides of the bends. As well, those ends
will each have exposed metal. Also, because the wire is coated
prior to trap construction, it can be seen that no benefit from
the structural potential of the coating of the wire is attained.
In the corresponding portion of trap 2 illustrated in
FIGURE 3, made according to the peocess oE the present
invention, clips lO are secured directly on the metal of the
mesh and ends of the wire from end portion 12 are bent o~er the
wire of the adjacent base 6 before coating with plastic. Tn
this manner all of the metal of the mesh and clips 10 are
completely shielded from the corrosive saline environment of
the ocean when the trae is in use. Also, the structueal
potential of the coating material i~ taken advantage Oe. When
the wires of side 6 and end 12 which are adjacent to each other
are clamped o~ o~herwise secured together and then coated, as
the coating hardens ovee them, it fuses adjacent wires
together, thereby adding stren~th and stopping the chaEfing
which would otherwise occur when the trap was in use. As
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previously indicated, this process thus greatly increases the
strength and life expectancy oE ~he trap without increasing its
land weight or increasing the gauge o-E the wire used Gr
inceeasing the overall cost of the material in the trap.
It is preferLed, in accordance with the present
invention, to use a recently developed method of coating the
wire mesh which method is called electrostatic airless
spraying. It is preferLed that the coating material be an
epoxy/polyester material which is more flexible and has better
scuff and corrosive resistant qualities than previously used
p.v.c. compositions. According to the electrostatic airless
seray method, a seray of powdered coating material is delivered
simultaneously from computer controlled guns onto the subject
wire mesh trap frame which is approeriately mounted in a vacuum
work area. When appropriate powder has been delivered to the
mesh of the trap, the trap is then moved to a heating booth
where the epoxy/polyester coating is cured and securely bonded
to the wire. The method according to the present invention
eliminates all exeosed ends of wire as well a6 eroviding
uniform thickness and increased bonding capacity on the wire
body o~ the trap. The structural capacity of the COatirlg
material is u~ed in combination with that of the wire to
provide the greatly increased strength achieved in the trap
made in accordance with the present invention.
Of course, once the metal mesh of the trap 2 has been
coated in accordance with the present in~ention, appropriate
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kitchen heads 16, parlor head 18 and door 20 can be installed
in the lobster trap in conventional fashion.
Thus it is apparent that there has been provided in
accordance with the invention an improved underwater trap for
marine life that fully satisfies the objects, aims and
advantages set forth above. While the invention has been
described in conjunction with a specific embodiment thereof, it
is evident that many alternatives, modifications and variations
will be apparent to those skilled in the art in light of the
lQ foregoing description. Accordingly, it is intended to embrace
all such alternatives, modifications and variations as fall
within the s~irit and broad scope of the invention.
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