U.S. patent application number 11/295016 was filed with the patent office on 2008-04-24 for optically transmissive armor composite.
Invention is credited to Richard L. Cook.
Application Number | 20080092729 11/295016 |
Document ID | / |
Family ID | 38049095 |
Filed Date | 2008-04-24 |
United States Patent
Application |
20080092729 |
Kind Code |
A1 |
Cook; Richard L. |
April 24, 2008 |
Optically transmissive armor composite
Abstract
An exemplary apparatus providing a substantially optically
transparent/translucent composite armor material is disclosed as
having: a first layer of hard transparent material (i.e., a glass
facing layer) adapted for attachment to a second layer of polymer
backing (i.e., a kinetic layer) and a layer of elastomeric bonding
material disposed between the first and second layers. Disclosed
features and specifications may be variously controlled, adapted or
otherwise optionally modified to improve and/or modify the
performance characteristics of the transparent/translucent armor
composite. Exemplary embodiments of the present invention generally
provide lightweight transparent/translucent armor for use as, for
example, bulletproof windows in vehicles and buildings.
Inventors: |
Cook; Richard L.;
(Flagstaff, AZ) |
Correspondence
Address: |
NOBLITT & GILMORE, LLC.
4800 NORTH SCOTTSDALE ROAD, SUITE 6000
SCOTTSDALE
AZ
85251
US
|
Family ID: |
38049095 |
Appl. No.: |
11/295016 |
Filed: |
December 5, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60633365 |
Dec 3, 2004 |
|
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Current U.S.
Class: |
89/36.02 |
Current CPC
Class: |
F41H 5/0492 20130101;
F41H 5/0407 20130101 |
Class at
Publication: |
89/36.02 |
International
Class: |
F41H 5/02 20060101
F41H005/02 |
Claims
1. A substantially optically transmissive armor composite, said
composite comprising: a facing layer having a first thickness, said
facing layer comprising an at least partially at least one of
transparent and translucent glass material; a kinetic layer having
a second thickness, said kinetic layer comprising an at least
partially at least one of transparent and translucent polymeric
material suitably configured for attachment to said first layer;
and an optional layer of an elastomeric material, said optional
layer at least partially disposed between said first layer and said
second layer; and wherein the ratio of said second thickness to
said first thickness is at least about unity.
2. The armor composite of claim 1, wherein said ratio of the
kinetic layer thickness to the facing layer thickness is about
1.625.
3. The armor composite of claim 1, wherein said facing layer is
suitably configured to at least one of: substantially blunt a
projectile striking the facing layer's surface; at least partially
remove a coaxial portion of a projectile striking the facing
layer's surface; at least partially diminish the structural
integrity of a coaxial portion of a projectile striking the facing
layer's surface; and at least partially deform the shape of a
projectile striking the facing layer's surface.
4. The armor composite of claim 1, where said kinetic layer is
suitably configured to at least partially reduce the kinetic energy
of a projectile penetrating at least partially into said kinetic
layer.
5. The armor composite of claim 1, wherein said facing layer is
substantially articulated.
6. The armor composite of claim 5, wherein said facing layer
comprises a plurality of at least one of discrete tiles, spheres,
marbles, polyhedra, cylinders and regular solids.
7. The armor composite of claim 1, wherein the indices of
refraction of the facing layer and the kinetic layer are
substantially equivalent for a pre-determined temperature
range.
8. The armor composite of claim 1, wherein said facing layer
comprises a plurality of hard facing sub-layers.
9. The armor composite of claim 8, wherein at least one of said
facing sub-layers is substantially articulated with a plurality of
at least one of discrete tiles, spheres, marbles, polyhedra,
cylinders and regular solids.
10. The armor composite of claim 9, wherein the articulation
boundaries of at least two articulated facing sub-layers are
configured in at least one of a substantially staggered geometry
and a substantially offset geometry.
11. The armor composite of claim 1, wherein said facing layer
comprises at least one of an amorphous glass material and a
crystalline glass material.
12. The armor composite of claim 1, wherein said kinetic layer
comprises a plurality of kinetic sub-layers.
13. The armor composite of claim 12, wherein the kinetic layers
comprise layers of at least one of polycarbonate, acrylic and
urethane interspersed with layers of elastomeric polymer.
14. A method for protecting an object from projectile damage behind
an at least partially optically transmissive barrier, said method
comprising the steps of: providing a facing layer having a first
thickness, said facing layer comprising an at least partially at
least one of transparent and translucent glass material; providing
a kinetic layer having a second thickness, said kinetic layer
comprising an at least partially at least one of transparent and
translucent polymeric material suitably configured for attachment
to said first layer; and providing an optional layer of an
elastomeric material, said optional layer at least partially
disposed between said first layer and said second layer; and
wherein the ratio of said second thickness to said first thickness
is at least about unity.
15. The method of claim 14, wherein said ratio of the kinetic layer
thickness to the facing layer thickness is about 1.625.
16. A substantially optically transmissive armor composite, said
composite comprising: a facing layer having a first thickness, said
facing layer comprising an at least partially at least one of
transparent and translucent glass material; a kinetic layer having
a second thickness, said kinetic layer comprising an at least
partially at least one of transparent and translucent polymer
material suitably configured for attachment to said first layer;
and an elastomeric layer comprising at least one polymer material,
said elastomeric layer disposed between said first layer and said
second layer; and wherein the ratio of said second thickness to
said first thickness is at least about unity.
17. The armor composite of claim 16, wherein said facing layer
comprises at least one of: two sheets of glass dimensioned with
approximate thicknesses of 3/32'' and 1/8'' respectively; two
sheets of glass dimensioned with approximate thicknesses of 3/32'';
and two sheets of glass dimensioned with approximate thickness of
1/8''.
18. The armor composite of claim 16, wherein said facing layer
comprises at least one sheet of glass dimensioned with an
approximate thickness of 1/8'' bonded to a polymer layer, wherein
said polymer layer is suitably dimensioned to contain spall
generated when a projectile strikes the surface of said facing
layer.
19. The armor composite of claim 16, wherein said kinetic layer
comprises a plurality of semi-rigid polymer layers interspersed
with layers of elastomeric polymer.
20. The armor composite of claim 16, wherein said kinetic layer
comprises a plurality of semi-rigid polymer layers having an
approximate thickness of about 1/4'' interspersed with layers of
elastomeric polymer having an approximate thickness of up to about
0.05''.
Description
RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent
Application Ser. No. 60/633,365 (entitled `Transparent Armor`)
filed in the United States Patent and Trademark Office on Dec. 3,
2004 by Richard Cook.
FIELD OF INVENTION
[0002] The present invention generally provides improved systems,
compositions and methods for substantially transparent/translucent,
breakage-resistant composite structures; and more particularly,
representative and exemplary embodiments of the present invention
generally relate to bullet-resistant windows and/or ballistic
laminate materials. In one representative aspect, various exemplary
embodiments of the present invention relate to ballistic glass and
transparent armor useful in military and security vehicle
applications. Still other representative embodiments of the present
invention relate to architectural and design elements for security
purposes in hostile environments.
BACKGROUND
[0003] In recent times, security has become increasingly important.
With respect to vehicle structures in general, military vehicles
generally require greater than average protection for the
occupants. This has given rise to various transparent armor
structures for windshields and side windows that are designed to
resist the incursion of small arms projectiles and shrapnel.
[0004] In constructing transparent armor, `bullet-proof glass`
sandwiches fabricated from glass are bonded together to form
complex composites. The resulting composites are generally
transparent and substantially free of optical distortion, while
maximizing the ballistic protection from penetrators. In use, the
inner and outer layers of the composite will typically be subjected
to shock, scratching, abrasion and adverse weather
conditions--particularly when a transparent armor composite is used
in military applications.
[0005] The various layers used in the composite may be chosen for
their different projectile resistance characteristics and
functions. For example, glass layers are hard and thus readily
erode bullets and are highly abrasion resistant; however, glass
layers are also brittle, which generally causes any glass layers
opposite a penetration threat to spall, which in turn creates
shrapnel fragments. The shrapnel may produce numerous projectiles
on the interior surface of the vehicle. The resulting spall (or
fragments) may in fact be more dangerous than the original
penetrator. Plastic material layers used as part of a composite
sandwich provide a means to introduce flexibility into the
transparent armor composite. The addition of one more plastic
layers to the composite changes the failure mode of the transparent
armor so it fails in a more ductile manner rather than spalling.
Acrylic-, polyurethane- and polycarbonate-based materials are among
the plastic materials which have been shown to have utility in
producing transparent armor composites.
[0006] One class of plastics that has proven both useful and
reliable in constructing transparent armor composites and
architectural bandit type barriers is polycarbonate. Polycarbonate
has demonstrated superior characteristics in terms of providing
overall protection because it demonstrates the highest spread
between brittleness transition temperature and heat distortion
temperature. For this reason, polycarbonates are generally
preferred materials in transparent armor composites. Unfortunately,
polycarbonate and the other plastic materials are also soft and
easily abraded by the action of dirt and dust. Furthermore,
polycarbonates are frequently adversely affected by solvents and
cleaning solutions when used to remove dirt. Thus, the cleaning of
surface dirt and grime will inevitably cause scratching. This
causes the optical properties to be adversely effected. Scratching
can cause the transparency of the armor composite to substantially
degrade in under one year. The substantial degradation of
transparency generally necessitates replacement of the composite.
Since transparent armor composites are expensive, frequent
replacement creates a substantial financial burden on maintenance
budgets.
[0007] In the conventional art, heavy glass in thicknesses in the
vicinity of 0.5 inches have been used to blunt and decelerate
bullets where the resulting spall is stopped by a polymeric
backing. The attendant peripheral damage, both ballistically and
optically, is severe and broad in scope.
SUMMARY OF THE INVENTION
[0008] In representative aspects, the present invention provides
systems, devices and methods for providing bullet resistant windows
(e.g., ballistic glass) utilizing thin laminate glazing over
resilient polymer backing capable of sustaining multiple close
proximity hits from a variety of munitions. Advantages of the
present invention will be set forth in the Detailed Description
which follows and may be apparent from the Detailed Description or
may be learned by practice of exemplary embodiments of the
invention. Still other advantages of the invention may be realized
by means of any of the instrumentalities, methods or combinations
particularly disclosed herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Representative elements, operational features, applications
and/or advantages of the present invention reside in the details of
construction and operation as more fully hereafter depicted,
described and claimed--reference being made to the accompanying
drawings forming a part hereof, wherein like numerals refer to like
parts throughout. Other elements, operational features,
applications and/or advantages may become apparent in light of
certain exemplary embodiments recited in the Detailed Description,
wherein:
[0010] FIG. 1 representatively illustrates a three-quarter,
isometric view of a substantially optically transmissive armor in
accordance with an exemplary embodiment of the present
invention;
[0011] FIG. 2 representatively illustrates a three-quarter,
isometric view of another substantially optically transmissive
armor in accordance with an exemplary embodiment of the present
invention;
[0012] FIG. 3 representatively illustrates a three-quarter,
isometric view of another substantially optically transmissive
armor in accordance with an exemplary embodiment of the present
invention;
[0013] FIG. 4 representatively illustrates a three-quarter,
isometric view of yet another substantially optically transmissive
armor in accordance with an exemplary embodiment of the present
invention;
[0014] FIG. 5 representatively illustrates a three-quarter,
isometric view of another substantially optically transmissive
armor in accordance with an exemplary embodiment of the present
invention; and
[0015] FIG. 6 representatively illustrates a three-quarter,
isometric view of still another substantially optically
transmissive armor in accordance with an exemplary embodiment of
the present invention.
[0016] Elements in the Figures are illustrated for simplicity and
clarity and have not necessarily been drawn to scale. For example,
the dimensions of some of the elements in the Figures may be
exaggerated relative to other elements to help improve
understanding of various embodiments of the present invention.
Furthermore, the terms "first", "second", and the like herein, if
any, are generally used for distinguishing between similar elements
and not necessarily for describing a sequential or chronological
order. Moreover, the terms "front", "back", "top", "bottom",
"over", "under", and the like, if any, are generally employed for
descriptive purposes and not necessarily for comprehensively
describing exclusive relative position or order. Any of the
preceding terms so used may be interchanged under appropriate
circumstances such that various embodiments of the invention
described herein, for example, are capable of operation in
orientations and environments other than those explicitly
illustrated or otherwise described.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0017] The following representative descriptions of the present
invention generally relate to exemplary embodiments and the
inventor's conception of the best mode, and are not intended to
limit the applicability or configuration of the invention in any
way. Rather, the following description is intended to provide
convenient illustrations for implementing various embodiments of
the invention. As will become apparent, changes may be made in the
function and/or arrangement of any of the elements described in the
disclosed exemplary embodiments without departing from the spirit
and scope of the invention.
[0018] In the past, multiple layers of glass in thicknesses in the
vicinity of 1/2'' were used in ballistic glass applications. The
resultant peripheral damage, both ballistically and optically, was
severe and broad in scope. Various embodiments of the present
invention provide a tough kinetic backing layer with an overlying,
relatively thin glass facing. The glass facing, being only of
sufficient thickness to spoil the pointedness of the incoming
projectile (e.g., 1/8'') may be bonded to the kinetic layer with an
elastic medium.
[0019] When a projectile strikes the thin glass facing, the facing
fractures, but in a much smaller area than that of convention
ballistic glass assemblies.
[0020] In accordance with an exemplary embodiment representatively
depicted in FIG. 1, the present invention provides an improved
optically transmissive armor. The optically transmissive armor has
a first layer 110 (e.g., a `facing layer` presenting a surface of
first contact to an incoming projectile), a second layer 100 (e.g.,
a `kinetic layer` for depleting the projectile's energy), and an
optional elastomeric layer at least partially disposed therebetween
(e.g., a `bonding layer` suitably configured for immobilizing
facing layer 110 with respect to the disposition of kinetic layer
110). The bonding layer may be composed of material having high
elongation characteristics, or any other suitable material capable
of mitigating temperature-rated expansion differentials associated
with the kinetic layer 100 and the facing layer 110. If the bonding
layer does not have suitable elongation characteristics over a
given temperature range, the bonding layer may become damaged
should the first and second layers expand or contract.
[0021] Generally, the thickness ratio of the kinetic layer 100
(e.g., polymeric material) to the facing layer 110 (e.g., glass
material) should be at least approximately unity. It will be
appreciated, however, that various other thickness ratios may be
alternatively, conjunctively or sequentially employed to achieve a
substantially similar result. It will also be appreciated that
different thickness ratios will produce different armor
characteristics that are uniquely adapted for particular threats or
operating environments.
[0022] The facing layer 110 may be comprised of a hard, glass-like
material that operates to blunt or otherwise deform a bullet or
projectile incident to its surface. The facing material may be
almost any composition, such as, for example: soda lime; crown;
borosilicate; aluminum oxynitride; sapphire; etc. Any glass
material, whether now known or otherwise hereafter described in the
art, may be alternatively, conjunctively or sequentially employed
in order to achieve a substantially similar result.
[0023] It should be noted that the term "projectile" may refer to
any object that may strike the surface of a optically transmissive
armor assembly. These may include projectiles used to attack the
integrity of the optically transmissive armor such as ballistic
items (bullets, shrapnel, thrown objects such as bricks, stones and
other similar objects) and self-propelled items (such as RPGs,
missiles, and other rocket-like objects). Projectiles may also
include objects used to directly strike the surface of the
optically transmissive armor, such as, for example: bricks, bats,
metal objects, stones, wooden clubs, etc. Finally, projectiles may
also include other objects that come into contact with the surface
of the optically transmissive armor. For example, if the optically
transmissive armor is used as part of a vehicle and that vehicle
were to be involved in an accident, portions of other vehicles, the
road, buildings or other objects may strike the surface of the
optically transmissive armor.
[0024] In the present embodiment, facing layer 110 has a preferable
thickness of about 1/8'' (.+-.approximately 50%). This is in
contrast to the conventional art, in which the principle structure
consists of a plurality of thick layers of glass--as conventional
glass layers are primarily used as kinetic depletion layers rather
than as facing and blunting layers, as representatively disclosed
and claimed in the instant application. In the present invention,
the glass material generally serves to merely blunt or otherwise
deform a projectile that is striking its surface, as opposed to
depleting a substantial fraction of the kinetic energy of the
projectile. Accordingly, glass facing layers in accordance with the
instant invention may be relatively thin compared to those of the
conventional art. A thinner layer of glass material is preferable
because it significantly reduces the weight of the armor assembly
without substantially decreasing penetration impedance, and
simultaneously provides improved optical characteristics and
retention of localized structural integrity after the armor
assembly is struck by a projectile.
[0025] For comparable stopping power, the present invention weighs
considerably less than that of conventional transparent armor
alternatives. Optical clarity after a projectile strike (i.e., hit
proximity performance) is also improved. As the thickness of the
glass facing material decreases, the damaged area (i.e., hit
radius) and glass loss also decreases. For example, the glass loss
in a 1/8'' facing is only about 1'' diameter; however, with 1/4''
glass, this area extends out to roughly 3'' in diameter or greater.
Accordingly, after a hit on a thinner layer of glass, less of the
material's optical characteristics will have been compromised.
[0026] By way of comparison, the optical occlusion of conventional
transparent armor extends out over a 6'' radius from any given hit.
Various exemplary embodiments of the present invention present an
occluded area of only about 1.5'' radius under similar conditions.
Second hit capability (i.e., the ability of the optically
transmissive armor assembly to stop a projectile that strikes its
surface in close proximity to the location of a prior hit) is
substantially improved due to the minimized glass loss that results
from use of thinner layers of glass facing. Generally, the glass
loss area after a first hit is greatly weakened and will not
provide much protection against a second hit. Accordingly, it is
preferable to employ a thinner layer of glass material in the
facing layer 110, thereby minimizing the amount of glass loss.
[0027] Present performance specifications for transparent armor
generally can require successful stoppage in a close hit pattern.
The disconcerting issue is that realistic threats are likely to
greatly exceed the specification requirement. The present invention
operates to overcome many problems associated with the conventional
art by providing a hit (and stoppage) capability in as low as 3/4''
spacing in all directions.
[0028] The kinetic layer 100 of the optically transmissive armor
generally comprises a tough, semi-rigid material having a high cut
and puncture resistance capable of catching the blunted projectile
by depleting its kinetic energy. For example, a single casting of a
clean, hard urethane polymer is an exemplary material that may be
employed in accordance with various embodiments of the present
invention. Hard urethane has demonstrated ease of casting and
superb close hit capability. Other materials having similar
characteristics (e.g., polycarbonate and acrylic), whether now
known or otherwise hereafter described in the art, may be
alternatively, conjunctively or sequentially employed to achieve a
substantially similar result.
[0029] In accordance with another exemplary embodiment, as
generally depicted in FIG. 2 for example, interspersed kinetic
layers 200, 220, 240 may comprise 1/4'' polycarbonate optionally
interleaved with relatively thin layers of urethane 210, 230. Of
course, significant benefit may be derived from an optically
transmissive armor substantially comprising polymer and elastomeric
layers having various other thickness dimensions in combination
with a relatively thin, hard facing layer 250. The layers'
dimensions may be altered by up to approximately .+-.50% and still
provide significant performance improvement over the conventional
art. Additionally, the ratio of the facing:kinetic thickness
dimensions may be significantly, which may be alternatively,
conjunctively or sequentially employed to achieve a substantial
benefit over the conventional art. It will also be appreciated that
different thickness ratios will produce different armor
characteristics that are uniquely adapted for particular threats or
operating environments.
[0030] In accordance with another exemplary embodiment, as
generally depicted in FIG. 3 for example, the facing may comprise
more than one sheet of material 310, 320, 330 overlying a
relatively thicker kinetic layer 300. Suitable configurations of
the facing may comprise two sheets of glass material 310, 320; or
the facing may comprise more than two sheets of glass material 310,
320, 330. It will be understood that although specific dimensions
for the facing material have been provided vide supra, significant
benefit may be derived from the use of other dimensions as well.
For example, the thicknesses of glass facing material may be
significantly altered and still provide substantial benefit over
the conventional art.
[0031] In accordance with still another exemplary embodiment, as
generally depicted in FIG. 4 for example, a first layer 410 may be
substantially articulated. Facing layer 410 may be articulated with
a plurality of tile elements 420. Tile elements 420 may comprise
different shapes, including, for example: discrete tiles (as
generally depicted in FIG. 4); spheres; polyhedra; cylinders;
and/or regular solids. Marbles (e.g., spheres) have been
demonstrated as an efficient tile element material (with net area
density calculated in the range of 10-12 lbs/ft.sup.2); however,
even plate glass (1/4'' to 1/2'' thick) mosaics have demonstrated
themselves to be quite efficient with densities in the 14
lbs/ft.sup.2 range. Various tiles 420 may be coupled together with
any suitable polymer matrix; however, in some applications, an
important consideration may involve matching the indices of
refraction of the optically transmissive tile elements 420 with
that of the polymer matrix to eliminate or otherwise reduce optical
distortions.
[0032] An exemplary glass/polymer composite embodiment comprises
borosilicate glass (having a refractive index of about 1.48) and a
low modulus, low temperature curing urethane. By addition of low R1
plasticizers, the index of refraction match can be nearly perfect
(within a given temperature range). This limit of temperature range
may preclude the use of sphere tile elements, but flat mosaics may
be useful under similar conditions. Although it is generally
preferable to match the indices of refraction for certain
applications, substantial benefit may be derived from an optically
transmissive armor where the indices of refraction are dissimilar.
For example, even with mismatched indices of refraction, optically
transmissive armor would still function well under a variety of
conditions in diverse operating environments. Articulation of the
facing layer 410 has demonstrated minimization of the glass loss
that results after a projectile strikes the surface of the first
layer 410 by inter alia localizing fracture expansion to a single
tile (or nearest-neighbors) regime. Accordingly, the loss of facing
material will generally be confined to the particular tile or tiles
420 that were struck by the projectile.
[0033] In accordance with yet another exemplary embodiment, as
generally depicted in FIG. 5 for example, the facing may comprise
more than one layer of substantially articulated glass material
510, 530, 540. The articulation may be accomplished via a plurality
of tile elements 520. Tile elements 520 may comprise different
shapes, including, for example: discrete tiles (as generally
depicted in FIG. 5); spheres; polyhedra; cylinders; and/or regular
solids. In the representative embodiment illustrated in FIG. 5,
boundaries 525 of tile elements 520 in the sheets of glass facing
540, 530, 510 may be suitably configured so as not to substantially
overlap. Such a configuration may find particular utility in
specific applications where the boundaries 525 of tiles 520 are
generally less able to blunt or deform a projectile than the normal
substantially unitary surface of tiles 520 themselves. Accordingly,
should a projectile strike a boundary 525 of a tile 520, the
projectile may not be sufficiently blunted such that the kinetic
layer 500 can effectively stop or otherwise impede the projectile.
By offsetting overlap of boundaries 525, it will be unlikely that a
projectile could have sufficient kinetic energy and angle-of-attack
to pass through a substantial linear distance of kinetic material
having first squarely struck any given boundary 525 of facing tiles
520.
[0034] Substantial benefit may be derived for configurations of the
facing layer(s) where some sheets of facing material are
substantially articulated and others are not. For example, the
first layer of facing material 540 presented to a projectile may
not be articulated, but the other sheets of facing material may be
articulated--thereby minimizing glass loss within those layers, as
well as reducing construction complexity and fabrication costs.
[0035] In accordance with yet another exemplary embodiment, as
generally depicted in FIG. 6 for example, the facing may comprise
more than one layer of glass material 610, 620, 630. Overlying
facing layer 630 may be substantially contiguous, so as to prevent
or otherwise impede dirt and/or other materials from lodging in the
interstitial regions between the tile elements of articulated
layers 610, 620. Tile elements may comprise different shapes,
including, for example: discrete tiles/blocks (as generally
depicted in FIG. 6); spheres; polyhedra; cylinders; and/or regular
solids. In the representative embodiment illustrated in FIG. 6, the
boundary edges between the tile elements in the articulated sheets
of glass facing 610, 620 may be suitably configured so as to
substantially overlap. Such a configuration may find particular
utility in specific applications where optically clarity is to be
maximized--especially where the indices of refraction between the
tile elements (as well as between overlying and underlying layers)
can be well-matched.
[0036] Optically transmissive armor composite assemblies, in
accordance with various embodiments disclosed herein, may be
constructed using vacuum and autoclave processes of laminate
stack-ups. The stacks may comprise a combination of multi-layered
thick glass, polymeric inner-layers and polymeric backing. The
composite laminate assembly may then be heated and cooled under
pressure. Various other embodiments of the present invention may
also be cast with conventional equipment.
[0037] In the foregoing specification, the invention has been
described with reference to specific exemplary embodiments;
however, it will be appreciated that various modifications and
changes may be made without departing from the scope of the present
invention as set forth herein. The specification and Figures are to
be regarded in an illustrative manner, rather than a restrictive
one and all such modifications are intended to be included within
the scope of the present invention. Accordingly, the scope of the
invention should be determined by the claims and their legal
equivalents rather than by merely the examples described above.
[0038] For example, the steps recited in any method or process
claim may be executed in any order and are not limited to the
specific order presented in the claims. Additionally, the
components and/or elements recited in any apparatus embodiment may
be assembled or otherwise operationally configured in a variety of
permutations to produce substantially the same result as the
present invention and are accordingly not limited to the specific
configuration recited in the claims.
[0039] Benefits, other advantages and solutions to problems have
been described above with regard to particular embodiments;
however, any benefit, advantage, solution to problem or any element
that may cause any particular benefit, advantage or solution to
occur or to become more pronounced are not to be construed as
critical, required or essential features or components of the
invention.
[0040] As used herein, the terms "comprising", "having",
"including" or any variation thereof, are intended to reference a
non-exclusive inclusion, such that a process, method, article,
composition or apparatus that comprises a list of elements does not
include only those elements recited, but may also include other
elements not expressly listed or inherent to such process, method,
article, composition or apparatus. Other combinations and/or
modifications of the above-described structures, arrangements,
applications, proportions, elements, materials or components used
in the practice of the present invention, in addition to those not
specifically recited, may be varied or otherwise particularly
adapted to specific environments, manufacturing specifications,
design parameters or other operating requirements without departing
from the general principles of the same.
* * * * *