Note: Descriptions are shown in the official language in which they were submitted.
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TWO IRON TOOL PACK AND METHOD FOR FORMING TALL METAL
BOTTLE SHAPED CONTAINERS AND SUCH A METAL BOTTLE
Technical Field
[0001] This disclosure relates to a tool pack for use in manufacturing metal
containers,
and in particular, to a tool pack that includes a redraw die and two ironing
dies for consistently
forming tall, aluminum cups for use in producing bottle-shaped containers at
high production
speeds.
Back2round of the Disclosure
[0002] Thin-walled, two-piece metal cans are often produced using drawing and
ironing
processes. In a drawing and ironing process, a flat circular blank of metal is
drawn through one
or more drawing dies to form a shallow preform cup. The preform cup is then
mounted on a free
end of a punch which extends from a reciprocating ram. The preform cup is then
passed through
one or more redraw dies and is then "ironed" by passing through one or more
ironing dies to
lengthen and thin the sidewall of the cup to form a formed cup. The term
"ironing" refers to the
operation of forcing the cup through an ironing die by means of the punch
resulting in a
reduction of the sidewall thickness of the cup and an elongation in the height
of the cup. Once
the cup is formed, a cutter removes any excess length of the cup and a
stripper assembly removes
the formed cup from the punch.
[0003] After one or more additional manufacturing steps, such as applying ink
or other
coatings to the cup, a liquid is placed in the cup and a lid is clamped onto
the formed cup to
complete the formation of the two-piece metal can. In order to economically
produce cans using
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drawing and ironing technology, drawing and ironing machines produce cans at a
high rate, for
example, 400 cans per minute. The general design and function of a bodymaker
used to form
two-piece metal cans is described in various patents, including U.S. 3,696,657
to Maytag filed
November 19, 1970; U.S. 4,685,322 to Clowes filed September 3, 1985; U.S.
5,335,532 to
Mueller et al. filed June 16, 1992; and 5,477,722 to Dziedzic et al. filed
Mach 13, 1995, the
disclosures of which are incorporated herein by reference for all purposes.
[0004] Recently, metal forming processes similar to those used to form two-
piece metal
cans have been used to form metal, bottle-shaped containers that have a narrow
neck and an open
end that is either threaded to receive a cap or includes a lip to receive a
crown. The narrow neck
and slender shape of metal, bottle-shaped containers provide more comfort for
drinkers holding
the bottle and also provide an appealing visual appearance. However, the
elongated body shape,
the narrow neck shape and the threaded or crowned opening of metal bottles
require increased
deformation of the original aluminum cup during the drawing and ironing
process and have
resulted in increased manufacturing defects and higher rejection rates when
compared with two-
piece aluminum can manufacturing.
Summary
[0005] In a first aspect, there is described an apparatus for making a bottle-
shaped
container that includes a bodymaker with a redraw die, a first ironing die and
a second ironing
die. The bodymaker has about a 30-inch stroke length and forms a metal cup
with a height of
between about 8.83 inches and about 9.76 inches and a wall thickness between
about .0083
inches and about .0096 inches.
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[0006] In some embodiments, the first ironing die reduces a sidewall thickness
of the cup
by between about 10 and about 40 percent.
[0007] In other embodiments, the second ironing die reduces a sidewall
thickness of the
cup by between about 35 and about 44 percent.
[0008] In yet other embodiments, the second ironing die reduces a sidewall
thickness of
the cup by between about 38 and about 42 percent.
[0009] In still other embodiments, the second ironing die reduces a sidewall
thickness of
the cup by between about 39 and about 41 percent.
[0010] In another embodiment, a contact portion of a working land of the
redraw die is
spaced about 4.5 inches from a contact portion of a working land of the first
ironing die.
[0011] In still another embodiment, a contact portion of a working land of the
first
ironing die is spaced about 6.6 inches from a contact portion of a working
land of the second
ironing die.
[0012] In yet another embodiment, a contact portion of a working land of the
redraw die
is spaced about 11.1 inches from a contact portion of a working land of the
second ironing die.
[0013] In some embodiments, the metal cup has a height between about 9.08
inches and
about 9.36 inches.
[0014] In a second aspect, there is described a method of creating a metal
bottle-shaped
container that includes providing a redraw die, a first ironing die and a
second ironing die,
wherein a contact portion of the redraw die is positioned about 4.5 inches
from a contact portion
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of the first ironing die and the contact portion of the first ironing die is
positioned about 6.6
inches from a contact portion of the second ironing die. The method also
includes forcing a cup
through the redraw die, the first ironing die and the second ironing die and
producing a finished
cup with a height to width ratio of about four at production speeds of about
200 to 230 cups per
minute.
[0015] In some embodiments, forcing the cup through the second ironing die
reduces a
sidewall thickness of the cup by between about 38 and about 42 percent.
[0016] In other embodiments, forcing the cup through the second ironing die
reduces a
sidewall thickness of the cup by between about 39 and about 41 percent.
[0017] In yet other embodiments, forcing the cup through the second ironing
die reduces
a sidewall thickness of the cup by about 40 percent.
[0018] In still other embodiments, the height to width ratio of the finished
cup is about
4.03.
[0019] In another embodiment, a bottle formed from the finished cup is about
9.4 inches
tall and has a sidewall thickness of between about .0083 inches and .0086
inches.
[0020] In still another embodiment, the cup includes 3104 series aluminum
alloy.
[0021] In some embodiments, the method includes providing a bodymaker, wherein
the
bodymaker includes about a 30-inch stroke and the redraw die, the first
ironing die and the
second ironing die are located in the bodymaker.
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[0022] In a third aspect, there is described a bottle made by a process that
includes the
steps of proving a bodymaker having about a 30-inch stroke and providing a
redraw die, a first
ironing die and a second ironing die, wherein a contact portion of a working
land of the redraw
die is about 4.5 inches from a contact portion of a working land of the first
ironing die and the
contact portion of the working land of the first ironing die is about 6.6
inches from a contact
portion of a working land of the second ironing die. The process also includes
forcing a cup
through the redraw die, the first ironing die and the second ironing die to
produce a formed cup
with a height between about 9.08 inches and about 9.36 inches and a sidewall
thickness of
between about .0083 inches and about .0086 inches.
[0023] In some embodiments, the first ironing die reduces the sidewall
thickness of the
cup by between about 10 and about 40 percent.
[0024] In other embodiments, forcing the cup through the redraw die, the first
ironing die
and the second ironing die occurs at between about 200 to 230 cups per minute.
[0025] Other aspects, features, and advantages will become apparent from the
following
detailed description when taken in conjunction with the accompanying drawings,
which are a
part of this disclosure and which illustrate, by way of example, principles of
the inventions
disclosed.
Description of the Fi2ures
[0026] The accompanying drawings facilitate an understanding of the various
embodiments.
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[0027] FIG. 1 is an exploded view of a bodymaker that includes a redraw die, a
first
ironing die and a second ironing die in accordance with this disclosure.
[0028] FIG. 2 is a side view of a redraw die, a first ironing die and a second
ironing die
in accordance with this disclosure.
[0029] FIG. 3 is a schematic side view of a cup formed by the tool pack of
FIG. 2 in
accordance with this disclosure.
[0030] FIG. 4. is a schematic side view of an thin-walled, aluminum, bottle-
shaped
container formed in part by the tool pack of FIG. 2 in accordance with this
disclosure.
[0031] FIG. 5 is a schematic block diagram showing a process for creating a
metal,
bottle-shaped container using the tool pack of FIG. 2 in accordance with this
disclosure.
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Detailed Description
[0001] FIGURE 1 is an exploded view of a bodymaker 100 that includes a ram 108
and
ram assembly 110, a yoke slide 112, a primary bulkhead 114, a secondary
bulkhead 116, a
redraw assembly 118, a redraw die 102, a first ironing die 104, a second
ironing die 106, a dome
die 120 and a stripper assembly 122. As will be discussed in more detail
below, the bodymaker
100 has a stroke length of about 30 inches and, when used in conjunction with
the tool pack 200
of FIG. 2, can be used to form a cup with a height to diameter ratio of about
4 and a total height
of about 9.4 inches which may then be used to form a bottle-shaped container
with a height to
diameter ration of about 4.
[0002] As described above, the longest stroke length currently available in a
commercial,
high-speed bodymakers is about 30 inches. Conventional tool pack designs in 30-
inch stroke
length bodymakers have been found to be ineffective in forming tall, thin-
walled, bottle-shaped,
aluminum containers on a consistent basis at high speeds. For example,
conventional tool pack
designs have been found to be ineffective in creating cups for use in forming
bottle-shaped metal
containers with heights over about 8 inches and necked portions with small
drinking openings
due to overworking of the metal material which causes manufacturing defects,
such as tearing
and splitting of the material. The tool pack design of the present disclosure
allows for high-
speed production of tall cups and allows for controlling the work performed on
the cups by each
die to reduce defect rates in the production of tall, bottle-shaped aluminum
containers. As will
be described in more detail below, it has been found that the tool pack allows
for the creation of
a bottle with an overall height of about 9.37 inches while avoiding contact
between the cup and
more than one die 102, 104 or 106 at a time during production to thereby lower
the risk of
tearing the cup material. It has also been found that the tool pack 200 allows
for an appropriate
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amount of work hardening to the cup to allow the cup to be necked, threaded
and flanged with
low instances of cracking or tearing during these operations.
[0003] FIG. 1 shows a 30-inch bodymaker 100 for use with an improved tool pack
design
200 (FIG. 2). The bodymaker 100 includes a ram 108 that reciprocates within
the bodymaker
100 to force a metal cup (not shown) through the tool pack 200, i.e., the
redraw die 102, the first
ironing die 104 and the second ironing die 106. The ram 108 may be any type of
ram 108 and
the ram 108 moves within the yoke slide 112 and the ram assembly 110. The
secondary
bulkhead 116 of the bodymaker 100 couples the ram assembly 110 to the primary
bulkhead 114.
The primary bulkhead 114 is coupled to the redraw assembly 118 and the dome
die 120.
[0004] Referring now to FIGURE 2, a tool pack 200, including a redraw die 102,
a first
ironing die 104 and a second ironing die 106, is shown in greater detail. The
redraw die 102, the
first ironing die 104 and the second ironing die 106 are generally aligned
along a central axis 218
and are spaced from one another within the bodymaker 100. The redraw die 102,
the first
ironing die 104 and the second ironing die 106 each include a working land
202, 204 and 206
that is configured to contact a cup (not shown) that is forced through the
tool pack 200. Each
working land 202, 204 and 206 includes a portion configured to contact the cup
as the cup is
forced through the die 102, 104 or 106, referred to herein as the contact
portions 208, 210 and
212. In use, the redraw assembly 118 accepts a cup, which may be formed of a
3104 series
aluminum alloy, and the ram 108 forces the cup through the redraw die 102. As
the cup
sidewalls contact the contact portion 208 of the working land 202 of the
redraw die 102, the
redraw die 102 elongates the sidewalls of the cup, decreases the sidewall
thickness of the cup
and decreases the overall diameter of the cup. After passing through the
redraw die 102, the cup
passes through the first and second ironing dies 104 and 106 where the cup is
further lengthened
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and the sidewall of the cup is further thinned as the cup contacts the contact
portions 210 and 212
of the working lands 204 and 206 of the first and second ironing dies 104 and
106, respectively.
Referring again momentarily to FIG. 1, after passing through the first ironing
die 104 and the
second ironing die 106, a bottom portion of the cup engages the dome die 120
to form a dome-
shaped indentation in the cup. The cup is then cut and the stripper assembly
122 removes the
cup from the ram 108. The cup may then be further shaped, for example, by
forming the cup
with one or more necking dies, expanding dies, threading machines, or other
forming equipment.
[0005] Referring again to FIG. 2, the distance between the dies 102, 104 and
106 is
controlled in order to consistently form tall, thin-walled cups for use in
creating tall, bottle-
shaped containers at high production speeds with low defect rates. In some
embodiments, the
contact portion 208 of the redraw die 102 is spaced by a distance 214 that is
between about 4.4
inches and about 4.6 inches from the contact portion 210 of the first ironing
die 104. In other
embodiments, the contact portion 208 of the redraw die 102 is spaced by a
distance 214 that is
between about 4.49 inches and about 4.55 inches from the contact portion 210
of the first ironing
die 104. In yet other embodiments, the contact portion 208 of the redraw die
102 is spaced by a
distance 214 that is about 4.5 inches from the contact portion 210 of the
first ironing die 104. In
some embodiments, the contact portion 208 of the redraw die 102 is spaced by a
distance 214
that is about 4.4924 inches from the contact portion 210 of the first ironing
die 104.
[0006] In some embodiments, the contact portion 210 of the first ironing die
104 is
spaced by a distance 216 that is between about 6.5 inches and about 6.7 inches
from the contact
portion 212 of the second ironing die 106. In other embodiments, the contact
portion 210 of the
first ironing die 104 is spaced by a distance 216 that is between about 6.6
inches and about 6.65
inches from the contact portion 212 of the second ironing die 106. In some
embodiments, the
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contact portion 210 of the first ironing die 104 is spaced by a distance 216
that is about 6.6265
inches from the contact portion 212 of the second ironing die 106.
[0007] In many cases, tool pack designs used to form metal cans include at
least one
redraw die and three ironing dies in a 30-inch stroke bodymaker. It has been
found, however,
that such "three-iron" tool packs do not consistently produce tall, thin-
walled cups for use in
forming tall, thin-walled bottle-shaped containers at high production speeds.
By restricting the
number of dies, and, specifically, by incorporating only 2 ironing dies 104
and 106 into a 30-inch
bodymaker 100, it has been found that defect rates in the production of tall,
thin-walled, bottle-
shaped containers can be reduced and that the amount of work performed on the
cup can be
controlled to more consistently produce acceptable cups for use in forming
tall, thin-walled,
bottle-shaped metal containers. In some embodiments, the above-described
distances between
the redraw die 102, the first ironing die 104 and the second ironing die 106
provide for a tool
pack 200 that can be contained within a 30 inch stroke bodymaker 100 to
consistently produce a
tall, aluminum, bottle-shaped containers at high production speeds. For
example, it has been
found that the above-described distances between the redraw die 102, the first
ironing die 104
and the second ironing die 106 provide for a tool pack 200 that can
consistently produce a cup
that has a total height between about 8.285 inches and about 9.76 inches and a
sidewall thickness
of between about .0083 inches and about .0086 inches at high production speeds
of between
about 200 and about 230 bottles or cups per minute. In other embodiments, it
has been found
that the above-described distances between the redraw die 102, the first
ironing die 104 and the
second ironing die 106 provide for a tool pack 200 that can consistently
produce a cup that has a
total height of about 9.4 inches and a sidewall thickness of between about
.0083 inches and about
.0086 inches at high production speeds of between about 200 and about 230
bottles or cups per
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minute. It is expected that higher production speeds and thinner sidewall
thicknesses will be
possible in the future. For example, it is expected that the tool pack will be
able to consistently
produce a cup that has a total height of about 9.4 inches and a sidewall
thickness of less than
about .0083 inches at high production speeds of between about 250 and about
280 bottles per
minute or higher.
[0008] In some embodiments, the percent reduction in sidewall thickness
performed on
the cup by the redraw die 102, the first ironing die 104 and the second
ironing die 106 is also
controlled to allow the cups to be used to form tall, thin-walled, bottle-
shaped containers at low
defect rates. In some embodiments, the first ironing die 104 reduces the
sidewall thickness of the
cup by between about 10 and about 40 percent. In some embodiments, the second
ironing die
106 reduces the sidewall thickness of the cup by between about 35 percent and
about 44 percent.
In other embodiments, the second ironing die 106 reduces the sidewall
thickness of the cup by
between about 38 percent and about 42 percent. In other embodiments, the
second ironing die
106 reduces the sidewall thickness of the cup by between about 39 percent and
about 41 percent.
In still other embodiments, the second ironing die 106 reduces the sidewall
thickness of the cup
by about 40 percent. It has been found that the above-described percents of
sidewall thickness
reduction allow for consistent production of tall, thin-walled cups for use in
producing tall,
bottle-shaped containers while avoiding many of the problems associated with
the use of more
than two ironing dies, such as over work hardening of the material and tearing
of the material.
[0009] FIG. 3 shows an exemplary cup 300 formed by the tool pack 200 of FIG.
2. As
described above, in some embodiments, the cup 300 formed by the tool pack 200
has a height
302 of between about 8.825 inches and about 9.76 inches and a diameter 304 of
between about
2.32 inches and about 2.326 inches. In other embodiments, the cup 300 has a
height 302
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between about 9.08 and about 9.36 inches and a diameter 304 of about 2.323
inches. In some
embodiments, the formed cup 300 has a height 302 to diameter 304 ratio of
between about 4.2
and about 3.8. In other embodiments, the formed cup 300 has a height 302 to
diameter 304 ratio
of between about 3.9 and about 4.03. In other embodiments, the formed cup 300
has a height
302 to diameter 304 ratio of about 4.03. In some embodiments, the formed cup
300 has a
sidewall thickness between about .0083 inches and about .0086 inches.
[0010] As described above, in some embodiments the cup 300 is formed into a
bottle-
shaped container, similar to the container 400 shown in FIG. 4, through one or
more necking,
expanding and threading operations, or a combination of other forming
operations. FIG. 4 is a
schematic of an exemplary embodiment of an elongated bottle 400 made using the
tool pack 200
of FIG. 2, in conjunction with other forming processes. While the bottle 400
has a particular
geometry, other bottle geometries, designs, and variations are possible and
are within the scope
of this disclosure. The elongated bottle 400 includes a concave bottom portion
415, a cylindrical
portion 410 and a neck portion 405 that includes a threaded portion 420. The
bottom portion 415
includes a circular perimeter 417. The concave shape of the bottom portion 415
provides
structural support for pressurized beverage fluids contained therein and is
made by the dome die
120 shown in FIG. 1. The cylindrical portion 410 extends from the circular
perimeter 417 of the
bottom portion 415 and has a uniform diameter 412. In some embodiments, the
cylindrical
portion 410 has a wall thickness of between about .0083 inches and about .0086
inches.
[0011] The neck portion 405 is formed near the open end 491 of the bottle 400.
The neck
portion 405 has a varying diameter reduced from the uniform diameter 412 of
the cylindrical
portion 410. The varying diameter forms a tapered profile 407 that gradually
constricts the neck
portion 405 toward an opening 423. In some embodiments, a shoulder portion 411
of the neck
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portion 405 extends at an angle of about 45 degrees from the cylindrical
portion 410. In some
embodiments, a top neck portion 413 of the neck portion 405 extends at an
angle of about 6
degrees from a center line 403 of the bottle 400. In other embodiments, the
top neck portion 413
of the neck portion 405 extends at an angle of about 5.75 degrees from the
center line 403 of the
bottle 400. The neck portion 405 has a wall thickness of between about .0093
inches and about
.0096 inches.
[0012] In some embodiments, the neck portion 405 includes a threaded portion
420 that
has one or more exposed threads 422. The threads 422 enable a threaded cap
(not shown) to
close and seal the opening 423. In some embodiments, the threaded portion 420
further includes
a folded flange 425 that is folded outwardly from the opening 423 for safe
contact when a
beverage is consumed from the bottle 400. In other embodiments, the neck
portion 405 does not
include a threaded portion 420 and the opening 423 is closed in another
manner, such as, for
example, with a crown (not shown).
[0013] In some embodiments, a printed indicia 418 is applied onto the outer
surface of
the bottle 400. The print indicia 418 may be further sealed with a clear or
transparent coat 419
applied to the outer surface of the bottle 400. An inner coating 430 may be
applied to an inner
surface of the elongated bottle 400 for separating a beverage from the metal
of the bottle 400.
[0014] In some embodiments, the cylindrical portion 410 of the bottle 400 has
a height of
between about 6.2 inches and about 6.4 inches. In other embodiments, the
cylindrical portion
410 has a height of about 6.38 inches. In some embodiments, the bottle 400 has
an overall
height of between about 7.4 inches and about 9.4 inches. In other embodiments,
the bottle has an
overall height of about 9.37 inches.
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[0015] It has been found that the above-described bottle 400 can be produced
with
increased consistency and with a lower defect rate using the tool pack 200
than with traditional
3-iron tool packs that include three ironing dies in a 30-inch stroke
bodymaker. For example, it
has been found that the tool pack 200 allows for the creation of a bottle with
an overall height of
about 9.37 inches while avoiding contact between the cup and more than one die
102, 104 or 106
at a time during production to thereby lower the risk of tearing the cup
material. It has also been
found that the tool pack 200 allows for an appropriate amount of work
hardening to the cup to
allow the cup to be necked, threaded and flanged with low instances of
cracking or tearing
during these operations.
[0016] FIG. 5 illustrates an embodiment of a method 500 of creating a metal
bottle using
the tool pack 200 of FIG. 2. In some embodiments, the method 500 is performed
on a
bodymaker 100 that has about a 30-inch stroke. In some embodiments, the method
500 begins
and a redraw die 102, a first ironing die 104 and a second ironing die 106 are
provided, as shown
at block 502. In some embodiments, the contact portion 208 of the redraw die
102 is spaced by a
distance 214 that is about 4.4924 inches from the contact portion 210 of the
first ironing die 104.
In some embodiments, the contact portion 210 of the first ironing die 104 is
spaced by a distance
216 that is about 6.6265 inches from the contact portion 212 of the second
ironing die 106. As
such, the redraw die 102, a first ironing die 104 and a second ironing die 106
fit within a 30-inch
stoke bodymaker. As described above, in some embodiments the distances between
the redraw
die 102, the first ironing die 104 and the second ironing die 106 allow for
the consistent creation
of a tall cups that can be formed into bottle-shaped containers 400 with a
total height of about 9.4
inches or more.
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[0017] A cup is then forced by a plunger through the redraw die 102 to
lengthen the walls
of a cup, to decrease the wall thickness of the cup and to decrease the
diameter of the cup, as
shown at block 504. The plunger then forces the cup through the first ironing
die 104, as shown
at block 506, and the first ironing die 104 reduces the sidewall thickness of
the cup by between
about 10 and about 40 percent. The cup is then forced through the second
ironing die 106, as
shown at block 508, and the second ironing die 106 reduces the sidewall
thickness of the cup by
between about 35 and about 44 percent. In some embodiments, the second ironing
die reduces
the sidewall thickness of the cup by between about 38 and about 42 percent. In
other
embodiments, the second ironing die reduces the sidewall thickness of the cup
by between about
39 and about 41 percent. In yet other embodiments, the second ironing die
reduces the sidewall
thickness of the cup by about 40 percent. Additional forming processes, such
as necking to form
a necked portion of the bottle, may be performed to create a bottle that has a
height to width ratio
of about 4, as shown at block 510.
[0018] In the foregoing description of certain embodiments, specific
terminology has
been resorted to for the sake of clarity. However, the disclosure is not
intended to be limited to
the specific terms so selected, and it is to be understood that each specific
term includes other
technical equivalents which operate in a similar manner to accomplish a
similar technical
purpose.
[0019] In this specification, the word "comprising" is to be understood in its
"open"
sense, that is, in the sense of "including", and thus not limited to its
"closed" sense, that is the
sense of "consisting only of'. A corresponding meaning is to be attributed to
the corresponding
words "comprise", "comprised" and "comprises" where they appear.
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[0020] In addition, the foregoing describes only some embodiments of the
invention(s),
and alterations, modifications, additions and/or changes can be made thereto
without departing
from the scope and spirit of the disclosed embodiments, the embodiments being
illustrative and
not restrictive.
[0021] Furthermore, invention(s) have been described in connection with what
are
presently considered to be the most practical and preferred embodiments, it is
to be understood
that the invention is not to be limited to the disclosed embodiments, but on
the contrary, is
intended to cover various modifications and equivalent arrangements included
within the spirit
and scope of the invention(s). Also, the various embodiments described above
may be
implemented in conjunction with other embodiments, e.g., aspects of one
embodiment may be
combined with aspects of another embodiment to realize yet other embodiments.
Further, each
independent feature or component of any given assembly may constitute an
additional
embodiment.
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