U.S. patent application number 10/777389 was filed with the patent office on 2004-11-11 for ballistic-resistant laminate assemblies and panels.
Invention is credited to Brillhart, Lee Walker III, Krueger, Ronald G., Stewart, Ricky William.
Application Number | 20040221712 10/777389 |
Document ID | / |
Family ID | 33424939 |
Filed Date | 2004-11-11 |
United States Patent
Application |
20040221712 |
Kind Code |
A1 |
Stewart, Ricky William ; et
al. |
November 11, 2004 |
Ballistic-resistant laminate assemblies and panels
Abstract
A sheet of ballistic-resistant fiber strands includes a
bi-directional array of bonding fibers interwoven with the
ballistic-resistant fibers to form a fiber panel. In one
embodiment, a sheet of laminated ballistic-resistant fibers is
joined to the first sheet of laminated ballistic-resistant fibers
with the ballistic-resistant fibers running in a second direction
as compared to the first fibers. In yet another embodiment,
individual laminated sheets of ballistic-resistant fibers are
stitched together to form packets of sheets that may be used
singularly or bundled together.
Inventors: |
Stewart, Ricky William;
(Mukilteo, WA) ; Brillhart, Lee Walker III;
(Seattle, WA) ; Krueger, Ronald G.; (Seattle,
WA) |
Correspondence
Address: |
PERKINS COIE LLP
PATENT-SEA
P.O. BOX 1247
SEATTLE
WA
98111-1247
US
|
Family ID: |
33424939 |
Appl. No.: |
10/777389 |
Filed: |
February 12, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10777389 |
Feb 12, 2004 |
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10421627 |
Apr 22, 2003 |
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10421627 |
Apr 22, 2003 |
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09528782 |
Mar 17, 2000 |
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6562435 |
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60125403 |
Mar 20, 1999 |
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Current U.S.
Class: |
89/36.05 ;
442/59 |
Current CPC
Class: |
B32B 5/10 20130101; Y10T
428/24058 20150115; B32B 2262/02 20130101; Y10T 428/24124 20150115;
B32B 2307/54 20130101; Y10T 442/20 20150401; D04H 3/04 20130101;
Y10T 442/2623 20150401; Y10T 156/10 20150115; B32B 27/12 20130101;
D04H 3/12 20130101; F41H 5/0485 20130101; B32B 5/12 20130101; B32B
2250/40 20130101; B32B 2571/00 20130101 |
Class at
Publication: |
089/036.05 ;
442/059 |
International
Class: |
F41H 005/08 |
Claims
1. A ballistic-resistant laminate assembly, comprising: a first
layer having a plurality of ballistic-resistant fiber strands
positioned adjacent to each other, a plurality of first bonding
strips and a plurality of second bonding strips, the first bonding
strips being spaced apart from each other by a selected distance,
being connected to the fiber strands and being positioned at a
first angle relative to the fiber strands, the second bonding
strips being spaced apart from each other by a selected distance,
being positioned at a second angle relative to the fiber strands,
and being cross-plied with the first bonding strips; a first
laminate film positioned on one side of the fiber strands and
bonded with the first or second bonding strips to the first layer;
and a second laminate film positioned adjacent to a side of the
fiber strands opposite the first laminate film.
2. The assembly of claim 1 wherein the fiber strands are
high-performance fibers having a tensile strength of at least 9
grams/denier.
3. The assembly of claim 1 wherein the first bonding strips are
ballistic-resistant bonding fibers coated with an adhesive
material.
4. The assembly of claim 1 wherein the first and second bonding
strips are arranged in a woven pattern.
5. The assembly of claim 1 wherein the second bonding strips are
ballistic-resistant bonding fibers coated with an adhesive
material.
6. The assembly of claim 1 wherein the second bonding strips
include high aramid fibers coated with an adhesive material.
7. The assembly of claim 1 wherein the second laminate film is
bonded to the first layer, with the fiber strands being laminated
between the first and second laminate films.
8. The assembly of claim 1 wherein the fiber strands are first
fiber strands, and further comprising a second layer having a
plurality of ballistic-resistant second fiber strands positioned
adjacent to each other, and a plurality of third bonding strips
spaced apart from each other by a selected distance and connected
to the second fiber strands, the third bonding strips being
positioned at a third angle relative to the second fiber strands,
the second fiber strands being cross-plied relative to the first
fiber strands.
9. The assembly of claim 8 wherein the first and second fiber
strands are bonded to each other with at least one of the first,
second, or third bonding strips.
10. The assembly of claim 8 wherein the first and second layers are
positioned immediately adjacent to each other between the first and
second laminate films.
11. The assembly of claim 8 wherein one of the first and second
laminate films is between the first and second layers.
12. The assembly of claim 8 wherein one of the first and second
laminate films is between the first and second layers, and further
comprising a third laminate film positioned adjacent to the second
layer opposite one of the first and second laminate films.
13. The assembly of claim 8 wherein the first layer is between the
first and second laminate films to form a first laminated layer,
and further comprising third and fourth laminated layers with the
second layer therebetween forming a second laminated layer adjacent
to the first laminated layer.
14. A ballistic-resistant laminate assembly, comprising: a
plurality of ballistic-resistant fiber strands; first bonding
fibers spaced apart from each other and interconnecting the fiber
strands, the first bonding fibers being oriented at a predetermined
angle relative to the fiber strands; and second bonding fibers
spaced apart from each other and connected to the fiber strands and
being at a predetermined angle relative to the first bonding
fibers, least the first or second bonding fibers being
ballistic-resistant fibers coated with a pressure or heat-sensitive
adhesive material, the first and second bonding fibers forming a
bi-directional array of bonding fibers that hold the fiber strands
in a substantially parallel orientation.
15. The assembly of claim 14 wherein the first bonding fibers are
interspersed within the fiber strands.
16. The assembly of claim 14 wherein the first and second bonding
fibers are arranged in a substantially woven pattern.
17. The assembly of claim 14 wherein the first and second bonding
fibers are aramid fibers coated with an adhesive material.
18. The assembly of claim 14, further comprising a first laminate
film adjacent to one side of the fiber strands and bonded to at
least one of the first or second bonding fibers, and a second
laminate film, the fiber strands and the array of bonding fibers
being laminated and substantially sealed between the first and
second laminate films with interstitial air pockets therebetween to
form a laminated ballistic-resistant assembly with positive
buoyancy.
19. The assembly of claim 14 wherein the fiber strands are first
fiber strands, the array of bonding fibers is a first array of
bonding fibers, and the first fiber strands and first array of
bonding fibers form a first layer, and further comprising a
plurality of ballistic-resistant second fiber strands positioned
adjacent to each other, and a bi-directional second array of
bonding fibers spaced apart from each other and interconnecting the
second fiber strands to form a second layer cross-plied with the
first layer.
20. The assembly of claim 19 wherein the first and second layers
are immediately adjacent to each other.
21. The assembly of claim 19 further comprising a first laminate
film is between the first and second layers.
22. The assembly of claim 19, further comprising first, second, and
third laminate films, the first layer being between the first and
second laminate films, and the second layer being between the
second and third laminate films.
23. The assembly of claim 19 wherein one of the first bonding
fibers is substantially aligned with the first fiber strands and
has a first color different from a color of the fiber strands, and
at least one of the second bonding fibers is substantially aligned
with the second fiber strands and has a second color different from
the first color and different from a color of the second fiber
strands, the first and second colors providing a visual indication
of the orientation of the first and second fiber strands relative
to each other.
24. The assembly of claim 14 wherein the fiber strands, the array
of bonding fibers and the laminate film are laminated together and
form a flexible ballistic-resistant panel.
25. The assembly of claim 14 wherein the fiber strands, the array
of bonding fibers and the laminate film are laminated together and
form a rigid ballistic-resistant panel.
26. A ballistic-resistant laminate assembly, comprising: a first
layer having ballistic-resistant first fiber strands positioned
adjacent to each other, a plurality of first bonding fibers and a
plurality of second bonding fibers, the first bonding fibers being
spaced apart from each other by a selected distance and being
positioned at a predetermined angle relative to the first fiber
strands, and the second bonding fibers being spaced apart from each
other by a selected distance and being cross-plied with the first
bonding fibers; a first laminate film positioned on one side of the
first layer; a second laminate film on a side of the first layer
opposite the first laminate film; a second layer having
ballistic-resistant second fiber strands positioned adjacent to
each other, a plurality of third bonding fibers, and a plurality of
fourth bonding fibers, the third bonding fibers being spaced apart
from each other by a selected distance and being positioned at a
predetermined angle relative to the second fiber strands, and the
third bonding fibers being spaced apart from each other by a
selected distance and being cross-plied with the fourth bonding
fibers, the second laminate film being between the first and second
layers; and a third laminate film positioned on a side of the
second layer opposite the second laminate film.
27. The assembly of claim 26, further comprising a fourth laminate
film positioned between the second laminate film and the second
layer.
28. The assembly of claim 26 wherein the first, second, third, or
fourth bonding fibers are ballistic-resistant fibers coated with an
adhesive material.
29. The assembly of claim 26 wherein the first, second, third, or
fourth bonding fibers are aramid fibers coated with a pressure or
heat-sensitive adhesive material.
30. The assembly of claim 26 wherein the first fiber strands are
aramid fibers.
31. The assembly of claim 26 wherein the first layer is
substantially sealably laminated between the first and second
laminate films with interstitial air pockets therebetween forming a
laminated layer with positive buoyancy.
32. The assembly of claim 26 wherein the second bonding fibers are
substantially parallel to the first fiber strands, and the first
bonding fibers are substantially perpendicular to the second
bonding fibers.
33. The assembly of claim 26 wherein the first and second bonding
fibers are arranged in a woven pattern.
34. The assembly of claim 26 wherein one of the first bonding
fibers is substantially aligned with the first fiber strands and
has a first color different from a color of the first fiber
strands, and at least one of the third bonding fibers is
substantially aligned with the second fiber strands and has a
second color different from the first color and different from a
color of the second fiber strands, the first and second colors
providing a visual indication of the orientation of the first and
second fiber strands relative to each other.
35. A ballistic-resistant laminate assembly, comprising: a
substantially planar first layer having a plurality of first fiber
strands positioned adjacent to each other, and a plurality of
bonding fibers spaced apart from each other by a selected distance
and connected to the first fiber strands, the bonding fibers being
positioned at a predetermined angle relative to the first fiber
strands, the first layer having generally opposing first and second
surfaces; a first laminate film adhered to the first surface of the
first layer; a second laminate film adhered to the second surface
of the first layer, the first and second laminate films sandwiching
the first layer therebetween forming a first laminated
ballistic-resistant sheet with the first fiber strands in a
substantially parallel orientation; a substantially planar second
layer having a plurality of second fiber strands positioned
adjacent to each other, the second layer having generally opposing
third and fourth surfaces, the third surface being adhered to the
second laminate film; and a third laminate film adhered to the
fourth surface of the second layer, the second and third laminate
films sandwiching the second layer therebetween forming a second
laminated ballistic-resistant sheet connected to the first
laminated ballistic-resistant sheet with the second fiber strands
in a substantially parallel orientation.
36. The assembly of claim 35 wherein the first and second fiber
strands are aramid fibers.
37. The assembly of claim 35 wherein the bonding fibers and the
first fiber strands are arranged in a substantially woven
pattern.
38. The assembly of claim 35 wherein the bonding fibers in the
first layer are substantially perpendicular to the first fiber
strands.
39. The assembly of claim 35 wherein the first fiber strands are
cross-plied at a selected angle relative to the second fiber
strands.
40. The assembly of claim 35 wherein the first layer is
substantially sealed between the first and second laminate films
with first interstitial air pockets therein and the second layer is
substantially sealed between the second and third laminate films
with second interstitial air pockets therein, the first and second
air pockets providing the assembly with a positive buoyancy.
41. A flexible, multiple-layer ballistic-resistant panel
comprising: a flexible first laminated sheet including a plurality
of first fiber strands positioned substantially parallel to each
other and forming generally opposing first and second surfaces, a
plurality of spaced-apart first bonding fibers connected to the
first fiber strands and positioned at an angle relative to the
first fiber strands, and a first laminate film adhered to the first
surface of the first fiber strands forming first interstitial
airspaces therein; a flexible second laminated sheet positioned
immediately adjacent to the first laminate sheet having a plurality
of second fiber strands positioned substantially parallel to each
other and forming generally opposing third and fourth surfaces, a
plurality of spaced-apart second bonding fibers connected to the
second fiber strands and positioned at an angle relative to the
second fiber strands, and a second laminate film adhered to the
third surface of the second fiber strands forming second
interstitial air spaces therein; and a joining member securely
retaining the first and second fiber strand laminated sheets
together forming a laminated structure with positive buoyancy.
42. The ballistic-resistant panel of claim 41 wherein the first
fiber strands are cross-plied at a selected angle with the second
fiber strands.
43. The ballistic-resistant panel of claim 42 wherein the first
fiber strands are aramid fibers.
44. The ballistic-resistant panel of claim 41 wherein the first and
second bonding fibers include ballistic-resistant fibers.
45. A ballistic-resistant laminate assembly, comprising: a
substantially planar first layer having a plurality of
ballistic-resistant first fiber strands positioned adjacent to each
other and a plurality of ballistic-resistant bonding fibers spaced
apart from each other and connected to the first fiber strands, the
bonding fibers being coated with an adhesive material and being
positioned at a predetermined angle relative to the first fiber
strands; a first laminate film adhered to the first layer with the
first fiber strands in a substantially parallel orientation, the
first layer and the first laminate film forming a first laminated
ballistic-resistant sheet; a second layer having a plurality of
unidirectional ballistic-resistant second fiber strands positioned
adjacent to each other; and a second laminate film adhered to the
second layer with the second fiber strands in a substantially
parallel orientation, the second layer and the second laminate film
forming a second laminated ballistic-resistant sheet connected to
the first laminated ballistic-resistant sheet.
46. The assembly of claim 45 wherein the bonding fibers are
substantially perpendicular to the first layer's fiber strands.
47. The assembly of claim 45 wherein the second laminate film is
between the first and second fiber strands.
48. The assembly of claim 45, further comprising a third laminate
film attached to the first layer sandwiching the first fiber
strands between the first and third laminate films forming a first
laminated layer, and further comprising a fourth laminate film
attached to the second layer sandwiching the second fiber strands
between the second and fourth laminate films forming a second
laminated layer adjacent to the first laminated layer.
49. The assembly of claim 48 wherein the first laminated layer
includes substantially sealed interstitial air spaces between the
first and third laminate films, and the second laminated layer
includes substantially sealed interstitial air spaces between the
second and fourth laminate films, the first and second laminated
layers having a positive buoyancy.
50. The assembly of claim 45 wherein the bonding fibers are aramid
fibers coated with a pressure or heat-sensitive adhesive.
51. The assembly of claim 45 wherein the bonding fibers are first
bonding fibers, and further comprising a plurality of
ballistic-resistant second bonding fibers coated with an adhesive
material spaced apart from each other and substantially parallel
with the second fiber strands, the second bonding fibers being
cross-plied with the first bonding fibers forming an array of
bi-directional bonding fibers.
52. The assembly of claim 51 wherein the first and second bonding
fibers are arranged in a woven pattern.
53. The assembly of claim 45 wherein the first and second laminate
sheets are flexible sheets joined together to form a flexible,
multiple-layer ballistic-resistant panel.
54. The assembly of claim 45 wherein the first and second laminate
sheets are joined together to form a rigid, multiple-layer
ballistic-resistant panel.
55. A flexible, multiple-layer ballistic-resistant panel,
comprising: a first flexible, unidirectionally oriented fiber
strand laminate sheet including a plurality of unidirectional first
fiber strands made of ballistic-resistant fibers positioned
substantially parallel to each other, a plurality of spaced-apart
first bonding fibers made of a ballistic-resistant material coated
with an adhesive and connected to first fiber strands and
positioned at an angle relative to the first fiber strands, and a
first laminate film adjacent to the first fiber strands; and a
second flexible, unidirectionally oriented fiber strand laminate
sheet positioned adjacent to the first flexible, unidirectionally
oriented fiber strand laminate sheet and having a plurality of
unidirectional second fiber strands made of ballistic-resistant
fibers positioned substantially parallel to each other, a plurality
of spaced-apart second bonding fibers made of ballistic-resistant
fibers coated with an adhesive and connected to the second fiber
strands and positioned at an angle relative to the second fiber
strands, and a second laminate film adjacent to the second fiber
strands.
56. The panel of claim 55 wherein the first bonding fibers are
substantially perpendicular to the first fiber strands.
57. The panel of claim 55 wherein the first bonding fibers and the
first fiber strands are made of the same ballistic-resistant
material.
58. The panel of claim 55 wherein the first unidirectionally
oriented fiber strand laminate sheet has third ballistic-resistant
bonding fibers coated with an adhesive material and positioned
substantially parallel with the first fiber strands and cross-plied
with the first bonding fibers to form an array of bi-directional,
ballistic-resistant bonding fibers.
59. The panel of claim 58 wherein the second unidirectionally
oriented fiber strand laminate sheet has fourth ballistic-resistant
bonding fibers coated with an adhesive material and positioned
substantially parallel with the second fiber strands and
cross-plied with the second bonding fibers to form a second array
of bi-directional, ballistic-resistant bonding fibers.
60. A ballistic-resistant laminate assembly, comprising: a first
layer having a plurality of ballistic-resistant fiber strands
positioned adjacent to each other, a plurality of first bonding
strips and a plurality of second bonding strips, the first bonding
strips being spaced apart from each other by a selected distance,
being connected to the fiber strands and being positioned at a
first angle relative to the fiber strands, the second bonding
strips being spaced apart from each other by a selected distance,
being positioned at a second angle relative to the fiber strands,
and being cross-plied with the first bonding strips; a first
laminate film positioned on one side of the fiber strands and
bonded with the first or second bonding strips to the first layer;
and a second laminate film adjacent to a side of the fiber strands
opposite the first laminate film.
61. The assembly of claim 60 wherein the fiber strands are high
performance fibers having a tensile strength of at least 9
grams/denier.
62. The assembly of claim 60 wherein at least one of the first and
second bonding strips are bonding fibers.
63. The assembly of claim 1 wherein at least one of the first and
second bonding strips include ballistic-resistant fibers coated
with an adhesive material.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is a continuation-in-part application of
U.S. patent application Ser. No. 10/421,627, entitled METHOD FOR
FORMING OR SECURING UNIDIRECTIONALLY-ORIENTED FIBER STRANDS IN
SHEET FORM, SUCH AS FOR USE IN A BALLISTIC-RESISTANT PANEL, which
is a continuation of U.S. patent application Ser. No. 09/528,782,
entitled METHOD FOR FORMING OR SECURING UNIDIRECTIONALLY ORIENTED
FIBER STRANDS IN SHEET FORM, SUCH AS FOR USE IN A
BALLISTIC-RESISTANT PANEL, filed Mar. 17, 2002, which is
incorporated herein in its entirety by reference, and which claims
priority to U.S. Provisional Patent Application No. 60/125,403,
also incorporated herein in its entirety by reference.
TECHNICAL FIELD
[0002] This invention relates to forming or securing fiber strands
in sheet form and, more particularly, to forming or securing fiber
strands in sheet form for use in a ballistic-resistant
laminate.
BACKGROUND OF THE INVENTION
[0003] Unidirectional fiber materials are used in
ballistic-resistant structures and are disclosed, e.g., in U.S.
Pat. Nos. 4,916,000, 4,079,161, 4,309,487, and 4,213,812. A
non-woven ballistic-resistant laminate referred to by the trademark
"Spectra-Shield" is manufactured by Allied-Signal, Inc. The
laminate structure is used in soft body armor to protect the wearer
against high-velocity bullets and fragments. "Spectra-shield" was
made by first forming a non-woven unidirectional tape, which was
composed of unidirectional polyethylene fibers and an elastic resin
material that held the fibers together. The resin penetrated the
fibers, effectively impregnating the entire structure with the
resin product. Two layers, or arrays, of the unidirectional tape
were then laminated together (cross-plied) at right angles to form
a panel. The panel was then covered on both sides with a film of
polyethylene. The film prevented adjacent panels from sticking
together when the panels were layered in the soft body armor. The
final panel was heavier and stiffer than desired for use as a
ballistic-resistant panel. The weight and stiffness were due in
part to the penetration of the entire structure with the resin
product.
[0004] Non-woven ballistic-resistant laminates without resins are
disclosed, e.g., in U.S. Pat. Nos. 5,437,905, 5,443,882, 5,443,883,
and 5,547,536. A sheet of non-woven ballistic-resistant laminate
structure was constructed of high performance fibers without using
resins to hold the fibers together. Instead of resin, thermoplastic
film was bonded to outer surfaces of two cross-plied layers of
unidirectional fibers to hold the fibers in place. The film did not
penetrate into the fibers. A sufficient amount of film resided
between the bonded layers to adhere the layers together to form a
sheet. Bonding the two layers of unidirectional fibers cross-plied
to one another was necessary to meet structural requirements of the
ballistic-resistant panel, such as impact force distribution. The
individual sheets were placed loosely in a fabric envelope of an
armored garment to form a ballistic-resistant panel.
SUMMARY
[0005] A ballistic-resistant laminate assembly is provided that
overcomes drawbacks experienced in the prior art and achieves other
benefits. One aspect of the invention provides a
ballistic-resistant laminate assembly having a first layer with a
plurality of ballistic-resistant fiber strands positioned adjacent
to each other, a plurality of first bonding strips, and a plurality
of second bonding strips. The first bonding strips are spaced apart
from each other by a selected distance and are at a first
orientation with the fiber strands. The second bonding strips are
cross-plied relative to the first bonding strips to form a
bi-directional array of bonding strips connected to the fiber
strands. The second bonding strips are spaced apart from each other
by a selected distance and are connected to the fiber strands at a
predetermined angle relative to the fiber strands. In one
embodiment, the first and second bonding fibers include
ballistic-resistant fibers coated with an adhesive material. In one
embodiment, the first and second bonding strips are bonding fibers
configured in a woven arrangement with the fiber strands. A first
laminate film is positioned on one side of the fiber strands and
bonded to the first layer. A second laminate film is positioned
adjacent to a side of the fiber strands opposite the first laminate
film.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a plan view of a ballistic-resistant fiber panel
with ballistic-resistant fiber strands and bonding fibers connected
to the fiber strands according to one embodiment of the
invention.
[0007] FIG. 2A is a plan view of a ballistic-resistant fiber panel
with ballistic-resistant fiber strands and an array of
bi-directional bonding fibers connected to the fibers in accordance
with another embodiment of the invention.
[0008] FIG. 2B is a plan view of a ballistic-resistant fiber panel
in accordance with another embodiment of the invention.
[0009] FIG. 2C is a plan view of a ballistic-resistant fiber panel
in accordance with another embodiment of the invention.
[0010] FIG. 2D is a plan view of a ballistic-resistant fiber panel
in accordance with yet another embodiment of the invention.
[0011] FIG. 3 is a partial, exploded isometric view of one
embodiment including thermoplastic sheets laminating the
ballistic-resistant fiber panel of FIG. 1.
[0012] FIG. 4 is a partial, exploded isometric view of another
embodiment of a laminated ballistic-resistant fiber panel without
interwoven bonding fibers.
[0013] FIG. 5 is a partial, exploded isometric view of another
embodiment of a laminated fiber panel including first and second
sets of laminated ballistic-resistant fiber panels cross-plied
relative to each together.
[0014] FIG. 6 is a partial, exploded isometric view of yet another
embodiment of a laminated fiber panel with alternating layers of
laminated ballistic-resistant fibers and laminate film.
[0015] FIG. 7 is a partial, exploded isometric view of another
embodiment of layers of laminated ballistic-resistant fibers and
laminate films.
[0016] FIG. 8 is a partial isometric view of several laminated
ballistic-resistant fiber panels stitched together to form a packet
under one embodiment of the invention.
[0017] FIG. 9 is a partial isometric view of another embodiment of
several laminated ballistic-resistant fiber panels stitched
together.
[0018] FIG. 10 is a partial, exploded isometric view of yet another
embodiment of several stitched-together packets of laminated
ballistic-resistant fiber panels.
[0019] FIG. 11 is an armored body garment under one embodiment of
the invention.
[0020] FIG. 12 is a partial, exploded isometric view of another
embodiment having a plurality of ballistic-resistant fiber panels
joined together.
DETAILED DESCRIPTION
[0021] The inventors have found limitations and inefficiencies with
respect to the performance and to the manufacturing of the prior
art ballistic-resistant panels. The prior art laminated panels gave
structure to the unidirectional fibers and served to prohibit
adjacent sheets from sticking together, but they also facilitated
movement between the sheets. Thus, the initial impact from, e.g., a
bullet to a ballistic-resistant panel comprised of loose laminated
sheets displaced and rotated the sheets within the pocket such that
the anti-ballistic characteristics were compromised for subsequent
bullets. Additionally, the impact from the bullet bunched and
pulled the individual fiber strands in the sheets and further
degraded the integrity of the ballistic panel.
[0022] When an armor vest is tested in accordance with nationally
recognized standards, the vest is shot six times at a
pre-established distance and in a specific shot pattern. The
inventors found with the prior art that, when the bullet pulled the
fibers toward entry, the bullet significantly weakened the areas
that fibers were pulled from such that by the fourth and fifth
shots, bullets penetrated a raised weakened strike area. Further,
in the absence of resins or adhesives, the number of fibers per
inch in a panel must be reduced to get opposing laminated sheets to
fuse together. Increasing the density of the fibers to improve
ballistic performance resulted in a panel that delaminated. To form
the prior art sheets, fiber spools were unwound as thermoplastic
sheets simultaneously laminated the fibers to provide alternating
layers of fibers and thermoplastic sheets. It was not always
feasible, economical, or ballistically prudent to simultaneously
bond the thermoplastic film on one side of the unspooling fibers.
Without the thermoplastic film, however, the unspooled fibers
lacked structure and collapsed.
[0023] Under one aspect of the invention, a ballistic-resistant
fiber panel includes a plurality of ballistic-resistant fiber
strands and bonding strips, such as a plurality of bonding fibers
connected to the fiber strands. Under another aspect of the
invention, two thermoplastic sheets laminate the fiber panel
between them. Under another aspect, one set of bonding strips is
connected to the fiber strands at one predetermined angle, and a
second set of bonding strips at another angle relative to fiber
strands is cross-plied with the first bonding strips to form an
array of bi-directional bonding strips connected to the
ballistic-resistant fiber strands. Under yet another aspect of the
invention, several of the laminated ballistic-resistant fiber
panels are stitched or otherwise bound together to form packets.
Methods for forming or securing ballistic-resistant fiber strands
in sheet form are described in detail below. In the following
description, numerous specific details are provided, such as
specific uses, fiber orientations, numbers of layers, etc., to
provide a thorough understanding of embodiments of the invention.
One skilled in the relevant art will readily recognize that the
invention can be practiced without one or more of the specific
details. In other instances, well-known structures or operations
are not shown or described in detail to avoid obscuring aspects of
the invention.
[0024] As illustrated in FIG. 1, a flexible ballistic-resistant
fiber panel 110 includes the bonding strips formed by bonding
fibers 130 interwoven with strands of ballistic-resistant fibers
120. As the ballistic-resistant fibers 120 are unspooled, they may
be passed through a comb guide where the ballistic-resistant fibers
are further paralleled and spaced into a predetermined uniform
density. In one embodiment, the ballistic-resistant fibers 120 are
aramid fibers, with a 1000 denier fiber construction and
approximately 17 ends/inch untwisted tows sheet construction. In
another embodiment, the ballistic-resistant fibers 120 are aramid
fibers, with a 840 denier fiber construction and approximately 20
ends/inch unidirectional untwisted tows sheet construction. In
other embodiments, the ballistic-resistant fibers 120 can be high
performance fibers having a tensile strength of at least 9
grams/denier.
[0025] As the ballistic-resistant fibers 120 are unspooled to form
a fiber panel 110, the bonding fibers 130 are interwoven at an
angle with respect to the ballistic-resistant fibers 120. In the
illustrative embodiment, the bonding fibers 130 are interwoven
perpendicular to the ballistic-resistant fibers 120 on
approximately one-inch centers. Preferably the bonding fibers 130
are spaced one-half inch to two inches, and more preferably, the
bonding fibers 130 are evenly spaced one inch apart. The bonding
fibers 130 are positioned to alternatively go under and over
adjacent sets of the ballistic-resistant fibers 120 in a woven
arrangement, thereby providing a bi-directional, or
multidirectional arrangement of fibers. In selected embodiments,
the sets of ballistic-resistant fibers 120 that the bonding fibers
go over or under have a width of about one-half inch to two inches,
so as to substantially correspond to the distance between adjacent
bonding fibers 130.
[0026] In one embodiment, the bonding fibers 130 are an ethylene
vinyl acetate with a polyester core. The coating may be made of
natural or manmade polymers, copolymers, waxes, or mixtures
thereof. The coating is configured to at least partially coat and
securely adhere to the ballistic-resistant fibers 120, thereby
substantially holding the ballistic-resistant fibers together.
Representative examples include, but do not limit the scope of use
to, the following: styrene, butadiene, poly-butadiene,
polyvinylchloride, polyethylene, polypropylene, polyvinyl acetate
(plasticized), acrylics, polyvinyl pyrrolidene compounds, natural
latex, paraffin wax of the hot melt type, casein, carboxy cellulose
esters, and ethers. The core may alternatively be constructed out
of nylon, cotton, or aramid fiber or other high performance fibers
having a tensile strength of at least 9 grams/denier. In other
embodiments, the bonding fibers 130 are constructed of a
ballistic-resistant fiber, such as an aramid fiber, with a coating
of heat-or pressure-sensitive adhesive that will adhere to the
ballistic-resistant fibers 120. The bonding fibers 130 can be
substantially the same as the ballistic-resistant fibers 120.
Alternately, the bonding fibers 130 can be a different size than
the ballistic-resistant fiber 120.
[0027] After the bonding fibers 130 are interwoven with the
ballistic-resistant fibers 120, they are bonded into a
ballistic-resistant oriented fiber panel 110, for example, with
heat and pressure from either static heat or an autoclave. The
desired temperature range during heating is preferably up to
500.degree. F., more preferably in the range of 225-375.degree. F.,
and most preferably 265.degree. F. under 45 psi of pressure. In
addition to heat bonding the bonding fibers 130 to the
ballistic-resistant fibers 120, bonding can be effected by other
methods depending upon the particular chemical composition of the
fiber's coating. For example, bonding can be done by moisture, the
use of organic solvents, high-pressure alone, or contact pressure.
Such bonding techniques, however, should not adversely affect the
ballistic-resistant fibers 120 or destroy the configuration of the
fibers that the bonding fibers 130 are to reinforce. Further, the
coating of the bonding fibers 130 must bond with whatever surface
coating or laminate is to be applied to the ballistic-resistant
fiber panel 110.
[0028] Interweaving the bonding fibers 130 with the
ballistic-resistant fibers 120 allows the fiber panel 110 to be
handled, transported, and processed either at a different location
or at a later time. This feature provides advantages, including
both efficiency and economy. Under traditional manufacturing
methods, it was necessary to secure the thermoplastic film onto one
side of the fibers at the same time the ballistic-resistant fibers
were unspooled to provide structure for the ballistic-resistant
fibers and to preserve the sheet configuration of the fibers. The
bonding fibers 130 provide this structure to the
ballistic-resistant fibers 120. Thus, a thermoplastic film may be
laminated to the ballistic-resistant fibers 120 either at the same
time as the ballistic-resistant fibers 120 are unspooled or at a
later time.
[0029] FIG. 2A is a plan view of a ballistic-resistant fiber panel
200, with a woven array of bi-directional bonding fibers 130
connected to the ballistic-resistant fibers 120 in accordance with
another embodiment of the invention. In the illustrated embodiment,
the bonding fibers 130 include a first set of spaced-apart bonding
fibers 228 generally perpendicular to the ballistic-resistant
fibers 120, although the bonding fibers can be oriented at another
selected angle relative to the ballistic-resistant fibers. The
fiber panel 200 also has a second set of spaced-apart bonding
fibers 230 substantially parallel with the ballistic-resistant
fibers 120. The first set of bonding fibers 230 is cross-plied and
arranged in a woven configuration with the second set of bonding
fibers 228 and with the ballistic-resistant fibers 120. The
cross-plied bonding fibers 228 and 230 form a bi-directional array
210 of bonding fibers that hold the ballistic-resistant fibers 120
in a parallel orientation. The fiber panel 200 can then be handled
and manipulated in the manufacturing processes to form
ballistic-resistant panels or the like. In one embodiment, the
first and second sets of bonding fibers 228 and 230 are aramid
fibers coated with selected adhesive, such as a heat and/or
pressure sensitive adhesive.
[0030] In another embodiment shown in FIG. 2B, the
ballistic-resistant fiber panel 200 has an array of bi-directional
bonding strips 1130 connected to the ballistic-resistant fibers
120. In the illustrated embodiment, the bonding strips 1130 include
a first set of spaced-apart bonding strips 1228 generally
perpendicular to the ballistic-resistant fibers 120, although the
bonding strips can be oriented at another selected angle relative
to the ballistic-resistant fibers. The fiber panel 200 also has a
second set of spaced-apart bonding strips 1230 substantially
parallel with the ballistic-resistant fibers 120. The first set of
bonding strips 1230 is cross-plied with the second set of bonding
strips 1228 and with the ballistic-resistant fibers 120. In one
embodiment, the first and second sets of bonding strips 1228 and
1230 are lengths of heat and/or pressure sensitive adhesive applied
to the ballistic resistant fibers 120.
[0031] The bonding strips 1228 and 1230 of one embodiment can be
applied the ballistic-resistant fibers 120 while the ballistic
resistant fibers are being unspooled and arranged in the parallel
configuration, or the bonding strips can be applied after the
ballistic-resistant fibers have been arranged in the parallel
configuration. The cross-plied bonding strips 1228 and 1230 form a
bi-directional array 1210 of bonding strips that hold the
ballistic-resistant fibers 120 in a parallel orientation. The fiber
panel 200 can then be handled and manipulated in the manufacturing
processes to form ballistic-resistant panels or the like. The
bonding strips 1228 and 1230 of different embodiments can be
fibrous or non-fibrous. The bonding strips 1228 and 1230 in
selected embodiments can be applied in a liquid or semi-liquid
format to form spaced-apart stripes of bonding material that act,
inter alia, to hold the ballistic-resistant fibers 120 together. In
other embodiments the bonding strips 1228 and 1230 can be elongated
lengths of material, such as a tape-like material, applied to the
ballistic resistant fibers 120 during or after the
ballistic-resistant fibers are arranged in the parallel
configuration.
[0032] In another embodiment shown in FIG. 2C, the
ballistic-resistant fiber panel 200 has the first set of
spaced-apart bonding fibers 228 oriented at an angle relative to
the ballistic-resistant fibers 120. The bonding fibers 228 in the
illustrated embodiment are made of ballistic-resistant fibers, such
as aramid fibers, coated with a selected heat and/or pressure
sensitive adhesive. In one embodiment, the angle of the first set
of bonding fibers 228 is generally between 0 degrees and 90
degrees. In another embodiment, the angle is generally between
approximately 30 degrees and 60 degrees, inclusive. The first set
of bonding fibers 228 can be woven with the ballistic-resistant
fibers 120. The second set of spaced-apart bonding fibers 230 are
oriented at second angle relative to the ballistic-resistant fibers
120 and are oriented at an angle relative to the first set of
bonding fibers 228. Accordingly, the first and second sets of
bonding fibers 228 and 230 provide a multi-axial array of bonding
fibers.
[0033] The bonding fibers 230 in the second set are also made of
ballistic-resistant fibers, such as aramid fibers, coated with a
selected heat and/or pressure sensitive adhesive. The bonding
fibers 230 in this embodiment are not perpendicular or parallel to
the ballistic-resistant fibers 120. In one embodiment, the angle of
the second set of bonding fibers 230 relative to the
ballistic-resistant fibers 120 is between 90 degrees and 180
degrees. In another embodiment, the angle is between approximately
120 degrees and 150 degrees, inclusive. In one embodiment, the
second set of bonding fibers 230 are woven with the
ballistic-resistant fibers 120 and with the first set of bonding
fibers 228. The first and second sets of bonding fibers 228 and 230
can be perpendicularly oriented relative to each other, or they can
be oriented at other angles to provide the bi-directional woven
array of bonding fibers. Accordingly, the ballistic-resistant
fibers and the first and second sets of bonding fibers 228 and 230
in the illustrated embodiment form a triaxial array of ballistic
resistant fibers that form the ballistic-resistant fiber panel.
[0034] In another embodiment, a ballistic-resistant panel is formed
with the bonding fibers 120 and three or more sets of spaced apart
bonding fibers made of ballistic-resistant fibers coated with a
selected heat and/or pressure-sensitive adhesive. Each set of these
spaced apart bonding fibers are angularly offset relative to each
other and relative to the ballistic-resistant fibers 120.
Accordingly, the ballistic-resistant panel is formed with a
multi-axial array of ballistic-resistant bonding fibers.
[0035] In one embodiment, the ballistic-resistant bonding fibers
228 and 230 can be made of the same material as the
ballistic-resistant fibers 120 and coated with a selected adhesive
coating. Alternatively, the bonding fibers 228 and 230 can be made
of an adhesive-coated ballistic-resistant material having
performance characteristics different than the ballistic-resistant
fibers 120. As an example, the ballistic-resistant bonding fibers
228 and 230 can be coated aramid fibers with a smaller denier fiber
construction and smaller diameter than the denier fiber
construction and diameter of the ballistic-resistant fibers
120.
[0036] In yet another embodiment shown in FIG. 2D, the
ballistic-resistant fiber panel 200 has a first set of spaced-apart
bonding strips 1228 oriented at an angle relative to the
ballistic-resistant fibers 120. The bonding strips 1228 in the
illustrated embodiment contain a selected heat and/or pressure
sensitive adhesive. In one embodiment, the angle of the first set
of bonding strips 1228 is generally between 0 degrees and 90
degrees. In another embodiment, the angle is generally between
approximately 30 degrees and 60 degrees, inclusive. The first set
of bonding strips 1228 can be applied during or after the
ballistic-resistant fibers 120 are arranged in the parallel
configuration. The second set of spaced-apart bonding strips 1230
are oriented at second angle relative to the ballistic-resistant
fibers 120 and are oriented at an angle relative to the first set
of bonding strips 1228. Accordingly, the first and second sets of
bonding strips 1228 and 1230 provide a multi-axial array of bonding
strips.
[0037] As illustrated in FIG. 3, lower and upper thermoplastic
films 340 and 342, respectively, are provided on bottom and top
sides of the single fiber panel 110, and then secured or laminated
thereto so that the ballistic-resistant fibers are securely
sandwiched between the films to form a flexible,
ballistic-resistant sheet 300. In one embodiment, the thermoplastic
films 340 and 342 are extremely thin, typically less than 0.35
mils, to maintain the flexibility of the laminated
ballistic-resistant sheet 300. Alternatively, thicker laminate
films up to approximately 0.5 mils may be used to form a laminated
fiber sheet of greater rigidity.
[0038] In one embodiment, the laminate film will coat the exterior
surfaces of the ballistic-resistant fibers 120 to encapsulate them,
but will not impregnate the fibers. Sufficient plasticized film
material flows between adjacent ballistic-resistant fibers 120 to
bond the thermoplastics films 340 and 342 to the
ballistic-resistant fibers. The thermoplastic films 340 and 342 may
be a polyethylene film. Due to the structure provided by bonding
fibers 130 and 230 (shown in phantom lines in FIG. 3), the
thermoplastic films 340 and 342 may be laminated over the
ballistic-resistant fibers 120 either as the ballistic-resistant
fibers are unspooled and interwoven with the bonding fibers 130 or
at a later time. The thermoplastic films 240 and 242 laminate to
each side of the ballistic-resistant fibers 120 to form the
flexible, laminated, ballistic-resistant fiber sheet 300. The
flexible sheet 300 may be used individually or may be combined with
other sheets as described below, to form a variety of items,
including ballistic-resistant panels.
[0039] The bonding fibers 130 further provide structure to which
the thermoplastic films 340 and 342 can bond. Because the
thermoplastic films 340 and 342 bond with the interwoven bonding
fibers 130, the fiber panel 110 may contain a greater density of
ballistic-resistant fibers 120. The bonding fibers 130 of these
embodiments thus provide at least two functions: the bonding fibers
help prevent the ballistic-resistant fiber panel from spreading or
delaminating before and after the thermoplastic films 340 and 342
are laminated over the ballistic-resistant fibers 120, and the
bonding fibers provide the panel enhanced buoyant characteristics.
The greater density of the ballistic-resistant fibers 120 in the
panel combine with the bonding fibers 130 to form interstitial air
pockets 344 trapped between the laminate films 340 and 342.
[0040] The bonding fibers 130 allow the density of the
ballistic-resistant fibers 120 to be maximized by giving the fiber
panel 110 further structure while preventing delamination of the
laminated fiber sheet 300 by bonding with the thermoplastic film.
The bond between the thermoplastic sheets 340 and 342 and the
bonding fibers 130 create equally spaced sealed interstitial air
pockets that, when used in a ballistic panel, produce buoyant
ballistic panels. In the embodiments shown in FIGS. 2A and 2B
having the bi-directional woven array 210 of bonding fibers, both
sets of the bonding fibers 228 and 230 act with the thermoplastic
films 340 and 342 shown in FIG. 3 to form the interstitial air
pockets 344 that provide the ballistic-resistant sheet 300 with a
positive buoyancy. Accordingly, a plurality of ballistic-resistant
sheets 300 can be joined together (as discussed in greater detail
below) to form a flexible, ballistic-resistant panel having
positive buoyancy. The buoyant flexible, ballistic-resistant panel
can be used to make a selected assembly, such as a
ballistic-resistant garment or the like.
[0041] The fiber panels 110, 200, and 300 discussed above are
substantially flexible ballistic-resistant panels. In other
embodiments, sufficient heat or heat with sufficient pressure can
be applied to the thermoplastic films 340 and 342 for a sufficient
duration to melt one or both of the thermoplastic films 340 and 342
into the ballistic-resistant fiber 120 to form a semi-rigid or
rigid structure. Before heating the thermoplastic films 340 and
342, the laminated ballistic-resistant fiber sheet 300 may be
configured into any variety of shapes. This semi-rigid or rigid
structure may be used alone or may be used in combination with
other panels to form any variety of items, including, but not
limited to, cargo boxes, storage boxes, aircraft containers, water
skis, snow skis, hockey sticks, vehicle bodies such as boat hulls,
and protective elements such as helmets for racing, military use,
or bicycling.
[0042] As illustrated in FIG. 4, another embodiment includes a
fiber panel 410 of ballistic-resistant fibers 120 with lower and
upper sheets of thermoplastic films 340 and 342 provided on a
bottom and top surface of the fiber panel to form a flexible
laminated ballistic-resistant fiber sheet 400. The
ballistic-resistant fiber panel 410 laminated on both sides by
thermoplastic films 340 and 342 provides a fiber sheet 400 with
maximum flexibility while providing sufficient structure to prevent
degradation of the fiber sheet's configuration. This
ballistic-resistant fiber panel 410 may be used individually or in
combination with other fiber panels disclosed herein.
Alternatively, the thermoplastic films 340 and 342 may be heated
such that the thermoplastic films will melt and encapsulate or
impregnate the individual fiber strands 120 resulting in a
substantially rigid sheet (not shown).
[0043] The decision to produce either a rigid or a flexible fiber
sheet is typically dictated by the end use of the fiber sheet 400.
Multiple pliable panels or sheets 110, 200, 300, or 400 can be used
to form flexible ballistic-resistant panels used in a wearable
garment, while providing ballistic protection to the wearer.
Several sheets 110, 200, 300, or 400 in a rigid configuration can
be used for other ballistic-related structures, such as helmets
configured to fit the wearer's head.
[0044] As illustrated in FIG. 5, another embodiment provides a
ballistic-resistant, laminated panel 500 that has a first laminated
fiber sheet 510 with ballistic-resistant fibers 120 oriented in a
first direction (as illustrated in FIG. 1), and a second laminated
ballistic-resistant fiber sheet 512 having ballistic-resistant
fibers 120 oriented in a second direction. As illustrated, the
sheets 510 and 512 each include bonding fibers 130 positioned
substantially perpendicular to the ballistic-resistant fibers 120
and interwoven with the ballistic-resistant fibers 120. In the
embodiments providing the array 210 of bi-directional bonding
fibers 130 and 230, the cross-plied bonding fibers are
substantially perpendicular to each other. Accordingly, one set of
bonding fibers 230 is substantially parallel to the fiber strands
120, and the other set of bonding fibers 130 is substantially
perpendicular to the fiber strands. In one embodiment, the bonding
fibers 230 can be ballistic-resistant fibers angularly offset
relative to the fiber strands 120, as discussed above with
reference to FIG. 2B.
[0045] In one embodiment, the bonding fibers 130 are visual
indicators that allow for easy confirmation that adjacent fiber
panels 110 are cross-plied relative to each other. As an example,
the bonding fibers 130 parallel to the ballistic-resistant fibers
120 in each laminated sheet 512 are colored differently than the
ballistic-resistant fibers. Accordingly, when the two laminated
sheets 510 and 512 are adjacent to each other, a person can quickly
and easily determine whether the ballistic-resistant fibers 120 are
cross-plied by looking at the relative orientation of the colored
bonding fibers. If the colored bonding fibers 130 of each adjacent
laminated sheet 510/512 are cross-plied relative to each other, the
person knows that the ballistic-resistant fibers are properly
cross-plied. In one embodiment adjacent fiber panels 110 can have
different colored bonding fibers 130, and in alternate embodiments
the bonding fibers in each fiber panel can have the same color
although different from the ballistic-resistant fibers 120. In the
embodiment having the bi-directional array 210 of bonding fibers
130, the bonding fibers can be configured so that some or all of
the bonding fibers 230 parallel to the ballistic-resistant fibers
120 have a different color than the cross-plied bonding fibers 228
in that fiber panel 110.
[0046] The laminated panel assembly 500 of the illustrated
embodiment has multiple cross-plied fiber panels 110, and each
fiber panel 110 is laminated between lower and upper laminate films
340 and 342, thereby forming laminated sheets 510 and 512 with a
configuration of film/fiber panel/film. Multiple laminated sheets
510, 512 can be joined together such that the ballistic-resistant
fibers 120 of adjacent layers are cross-plied relative to each
other. The resulting laminated sheet 500 has a lamination
configuration of film/fiber panel/film/film/fiber panel/film . . .
The multiple laminated layers 510, 512 can be retained together by
an adhesive provided between layers, or by stitching the layers
together or by other laminating techniques. As discussed above, the
bonding fibers 130 provide structure to the ballistic-resistant
fibers 120 and allow the panel 110 to be manufactured without the
thermoplastic film 340 or 342. Alternatively, if the thermoplastic
film 340 or 342 is bonded to either a first or a second surface
when the ballistic-resistant fibers 120 are unspooled and combined
with the bonding fibers 130 in the weave pattern to form the
ballistic-resistant panel 110, then the thermoplastic film may be
used to provide additional structure to the panel.
[0047] When the ballistic-resistant fibers 120 are combined with
the bonding fibers 130 in the weave pattern, layered on or between
thermoplastic films 340 and 342, and laminated to produce a
flexible sheet 500, the resulting flexible sheet is easy to handle
without damaging, loosening, or substantially degrading the
effectiveness of the ballistic-resistant fibers. The flexible,
laminated sheet 500 is also quite buoyant because of the
interstitial air pockets 344 trapped within the sheet between the
laminate films 340 and 342.
[0048] FIG. 6 is a partial exploded isometric view of an alternate
embodiment of a laminated fiber panel sheet 600. The laminated
sheet 600 includes a first fiber panel 110 with the
ballistic-resistant fibers 120 aligned in one direction. A second
fiber panel 110 is cross-plied with the first fiber panel so that
the ballistic-resistant fibers 120 of the second panel are
substantially perpendicular to the ballistic-resistant fibers of
the first panel. Accordingly, the laminated sheet 600 provides the
cross-plied layers of the ballistic-resistant fibers 120. In other
embodiments, the fiber panels 110 can be oriented with the
ballistic-resistant fibers 120 at selected angles relative to each
other, and not necessarily limited to a perpendicular orientation.
In other embodiments, additional fiber panels 110 can be provided
in the laminated sheet 600, and each fiber panel 110 can be
selectively oriented in a cross-plied configuration relative to the
adjacent layers as desired.
[0049] In the laminated sheet 600 as illustrated in FIG. 6, the
first fiber panel 602 is bonded or otherwise adhered to a lower
laminate film 606 such that the lower laminate film is attached to
the bottom surface of the first fiber panel. A middle laminate film
608 is attached to the top surface of the first fiber panel 602, so
that the first fiber panel is sandwiched between the lower and
middle laminate films 606 and 608. The second fiber panel 604 is
adhered along its bottom surface to the middle laminate film 608 so
the middle laminate film is sandwiched between the first and second
fiber panels 602 and 604. An upper laminate film 610 is adhered to
the top surface of the second fiber panel 604. Accordingly, the
structure of the laminated sheet 600 provides alternating layers of
film and fiber panel to provide a configuration of film/fiber
panel/film/fiber panel/film/ . . . with each successive fiber panel
110 being cross-plied relative to its adjacent fiber panels. Each
of the fiber panels 602/604 can have the bonding fibers 130 or the
array 210 of the bi-directional bonding fibers.
[0050] FIG. 7 is a partial exploded isometric view of another
embodiment of a laminated sheet 700. The laminated sheet 700
includes a first ballistic-resistant fiber panel 702 directly
attached to a second ballistic-resistant fiber panel 704 that has
the ballistic-resistant fibers 120 cross-plied relative to the
ballistic-resistant fibers of the first fiber panel. The bonding
fibers 130/230 provide adhesive characteristics that at least
partially bond the first and second fiber panels 702 and 704
together. The first and second laminated panels 702 and 704 can be
provided with one set of spaced-apart bonding fibers 130 at a
selected angle relative to the ballistic-resistant fibers 120
(e.g., perpendicular). In other embodiments, fiber panels 702 can
include the array 210 of bonding fibers 130, as discussed
above.
[0051] The laminated sheet 700 illustrated in FIG. 7 has a bottom
laminate film 340 attached to the bottom surface of the first fiber
panel 702, such that first fiber panel is between the laminate film
and the second fiber panel 704. The laminated sheet 700 also has a
top laminate film 342 attached to the top surface of the second
fiber panel 704, such that the second fiber panel is between the
top laminate film and the first fiber panel 702. Accordingly, the
laminated sheet 700 has a lamination configuration of
film.backslash.fiber panel.backslash.fiber panel.backslash.film.
The laminated sheet 700 illustrated in FIG. 7 shows the use of only
two laminated panels 702 and 704, although alternate embodiments
can provide additional layers of fiber panels between the laminate
films 340 and 342. The laminated sheet 700 can be a flexible sheet,
but in other embodiments, the laminated sheet can be a semi-rigid
or rigid structure.
[0052] FIG. 8 is an isometric view of a stack of layers 800 of
laminated sheets stacked on top of one another with the
ballistic-resistant fibers 120 of each fiber panel 110 selectively
oriented relative to the ballistic-resistant fibers of adjacent
fiber panels, such as parallel, perpendicular, or at other angles.
The stack of layers 800 can be made up of multiple layers of any
one of the laminated fiber sheets 300, 400, 500, 600, and/or 700
discussed above, or any mixed combination of the laminated fiber
sheets. The stack of layers 800 is secured together by stitches 810
to form a packet 820.
[0053] In another embodiment, adjacent sheets 300/400/500/600/700
can be secured together with an adhesive provided between the
adjacent layers. The adhesive can be applied in selected patterns
on the facing surfaces, so as to control the stiffness or rigidity
of the resulting stack of layers 800. The stack of layers 800
adhered together can also be stitched together at selected
locations or patterns as needed for the particular application for
which the packet 820 is to be used. Further, any one of the sheets
illustrated in FIGS. 1-7 may be used in any combination to form the
packet 820. Specifically, when using the ballistic-resistant
laminated sheets 500 illustrated in FIG. 5 to form the packet 820,
preferably three to eight sheets are sewn together to form the
packet 820, more preferably four to six panels, and most preferably
five panels are used to form the packet. When using the
ballistic-resistant fiber sheets 300 or 400 (FIG. 3 or 4) to form
the packet 820 for use in a ballistic-resistant panel assembly, the
sheets are placed such that the orientation of ballistic-resistant
fibers is rotated a selected angle with respect to adjacent
sheets.
[0054] Stitching the layers 800 together to form the packet 820
provides improved resistance to ballistic penetration in a
ballistic panel with fewer total fiber panels required, as
described below. In one embodiment, preferably four to ten packets
of laminated sheets 500 are used to form a ballistic panel, more
preferably four to eight packets and most preferably six packets
are used to form a ballistic-resistant packet 820. When a bullet
hits a ballistic-resistant panel 820, the bullet penetrates the
initial layers 500 and the impact force of the bullet displaces
secondary layers. When the ballistic-resistant panel 820 is made up
of several individual ballistic-resistant fiber sheets or panels,
the force of the bullet causes some fibers in the panel to push
apart and separate and other fibers at the tip of the bullet to
bunch. Adjacent fibers that the bullet does not actually penetrate
are pulled out of position and weakened by the impact force of the
bullet. This creates a path of reduced resistance through the
panel. The result is that the integrity of the ballistic-resistant
panel is significantly impaired after the first impact. Packets of
ballistic-resistant fiber layers retain the benefit that the
movement between the individual layers allows, i.e., shifting the
bullet off course and diffusing the straight-line penetration of
the bullet, while decreasing the penetration and the bunching
caused by the bullet. The packets act like individual panels within
the ballistic-resistant panel in that each individual packet acts
independently of the adjacent packet. Thus the bullet's trajectory
angles at each packet so that it does not create a path through the
panel.
[0055] Fewer layers are used to form a ballistic-resistant panel of
equivalent characteristics compared to prior systems; therefore,
the resultant panel is more flexible and lighter in weight. When a
bullet impacts a ballistic-resistant panel, the panel is subject to
both the impact force of the bullet and a reverberating energy wave
sent out ahead of the bullet. The components of the packet of this
embodiment combine to provide a more efficient ballistic-resistant
panel. Components include any one of or a combination of the
following: density of the ballistic-resistant fibers in the panel,
bonding thread, the cross-plied positioning of the fiber panels,
thermoplastic films, the laminated fiber panels, and laminated
panel assemblies stitched together in packets. The interaction
between the individual packets works in a cooperative effort to
provide an improved ballistic-resistant panel. Among other things,
sewing the layers in a packet maximizes the anti-ballistic
properties of the individual layers such that the resultant packet
is stronger than the sum of the individual layers. Additionally,
because fewer layers are required, the ballistic-resistant panel is
less expensive to manufacture.
[0056] Stitching the layers 800 to form the packet 820 may be done
by any variety of stitching patterns and is illustrated in FIG. 8
as a diamond pattern. An alternative pattern includes vertical
stitching perpendicular to the ballistic-resistant fibers. Vertical
stitching helps prevent the fibers from pulling side to side.
Vertical stitches are preferably evenly spaced, more preferably
evenly spaced 2"-4" apart and most preferably evenly spaced 3"
apart. Stitching patterns may also include perimeter stitching,
continuous and noncontinuous patterns, and any other variety of
stitching patterns. In addition to stitching to secure the sheets
together to form a packet, any one of a number of devices,
including, but not limited to, the following may be used: staples
(permanent plastic or metal); dry or wet adhesive applied directly
or on strips such as double-sided tape; various patterns of bar
tacks; interlocking tabs in the sheets themselves or slots in the
laminate; heat-fusible thread on the exterior of select sheets;
stacking two or more thermoplastic films and applying heat while
pressing them together and taking advantage of the "sticky"
properties of the film element of the laminate; fine Velcro or
similar hook and loop material between the layers of sheets, snaps,
any permutations and/or combinations of all the above devices;
induced static electrical charge; and interwoven magnetic material.
Additionally, a wide variety of materials may be used for the
stitching thread, including natural and manmade fiber threads,
polymer-based threads (such as fishing line), fine steel or other
metal or composite or alloy wire, and racket sports string
(including natural, such as catgut, and synthetic materials).
[0057] FIG. 9 illustrates another embodiment of a packet 900 of
several ballistic-resistant fiber sheets affixed together. As
discussed above, any combination of sheets may be used to form the
packet 900, including, but not limited to, this illustrated
combination layering of different sheets 500, 400, 300, 400 and
500. As the individual sheet configurations have specific features
or strengths, the positioning of the sheets within the packet will
serve to highlight those features or strengths.
[0058] As illustrated in FIG. 10, the packets 820 or 900 are
combined to form a ballistic-resistant panel 1000. As is further
illustrated in FIG. 11, one or more packets 820 or 900 can be
bundled together and inserted in pockets 1100 to form a
ballistic-resistant panel 1000. This ballistic-resistant panel 1000
may be used as illustrated in a structure such as a vest 1150. The
packets 820 or 900 increase ballistic-resistant efficiency by
helping to hold the sheets in position. Traditionally, the first
impact or shot to the ballistic-resistant panel 1000 caused
displacement and rotation of the sheets, which resulted in a less
efficient ballistic-resistant panel for second or subsequent
sheets. The stitching 810 or otherwise securing the individual
sheets to form packets 820 or 900, and then bundling the packets
820 or 900 together to form a ballistic-resistant panel 1000,
reduces the shifting and rotation caused by the initial shot.
[0059] FIG. 12 is a partially exploded isometric view of a
ballistic-resistant panel 1200 in accordance with another
embodiment. The ballistic-resistant panel 1200 is formed by a
plurality of ballistic-resistant fiber sheets 1202. Laminate films
are not provided between the ballistic-resistant sheets 1202 in
this embodiment. The sheets 1202 have the plurality of
ballistic-resistant fibers 120 a set of spaced-apart bonding fibers
130 woven or bonding strips at a selected angle relative to the
ballistic-resistant fibers. The bonding fibers 130 are shown in
FIG. 12 at one angle although other angular orientations, including
a perpendicular orientation, could be used. The bonding fibers 130
can be ballistic-resistant fibers, such as aramid fibers, coated
with a selected heat and/or pressure sensitive adhesive. In one
embodiment, each ballistic-resistant sheet 1202 also has a second
set of spaced-apart bonding fibers 130 or bonding strips woven with
the first set of bonding fibers and with the ballistic-resistant
fibers 120. Accordingly, each ballistic-resistant fiber sheet 1202
is a multi-directional array of fibers.
[0060] The ballistic-resistant sheets 1202 are oriented so the
ballistic-resistant fibers 120 of each sheet is cross-plied at a
selected angle relative to the ballistic-resistant fibers of the
adjacent sheets. The ballistic-resistant fibers 120 of adjacent
sheets can be cross-plied approximately a 90.degree. orientation,
although angular orientations can be used. When the
ballistic-resistant sheets 1202 are positioned together to form the
panel 1200, the bonding fibers 130 in each sheet bond to the
ballistic-resistant fibers 120 of the sheet and also to the
ballistic-resistant fibers and/or the bonding fibers of the
adjacent sheets. The bonding fibers 130 securely retain the
adjacent ballistic-resistant sheets 1202 together while maintaining
the desired degree of flexibility or rigidity of the
ballistic-resistant panel 1200. The plurality of
ballistic-resistant sheets 1202 in alternate embodiments can also
be stitched together, as discussed above.
[0061] The impact of the bullet indents the ballistic-resistant
panel and causes some of the fibers in the ballistic-resistant
panel to compact at the front of the bullet while stretching and
pulling other fibers out of position as the bullet moves through
the ballistic-resistant panel. Additionally, the indentation from
the force of the bullet in the ballistic-resistant panel in one
location causes a resulting protrusion of the panel's flat surface
surrounding the indentation. This protrusion can buckle the surface
of the entire panel depending on the entry location of the bullet.
This buckling creates an air pocket between the panel and the
wearer's chest, which in turn impacts the integrity of the entire
ballistic-resistant panel.
[0062] The various embodiments described above can be combined to
provide further embodiments. All of the above U.S. patents and
applications are incorporated by reference. Aspects of the
invention can be modified, if necessary, to employ the systems,
circuits, and concepts of the various patents and applications
described above to provide yet further embodiments of the
invention.
[0063] These and other changes can be made to the invention in
light of the above detailed description. In general, in the
following claims, the terms used should not be construed to limit
the invention to the specific embodiments disclosed in the
specification and the claims, but should be construed to include
all ballistic-resistant fiber sheets that operate under the claims.
Accordingly, the invention is not limited by the disclosure, but
instead its scope is to be determined entirely by the following
claims.
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