Abstrict A ballistic body armor and dehumidification system includes a flexible
carrier containing a watertight sealed pouch which itself contains
a desiccant and a stack of substantially vertical layers of ballistic
material whose performance degrades under certain conditions in
the presence of moisture. The watertight sealed pouch is mounted
into the carrier so as to cover a portion of a user's body. The
desiccant is mounted into the pouch so that either it is, or its
effect is, distributed uniformly across the ballistic material to
uniformly reduce the humidity level within the pouch.
Claims 1. Ballistic body armor comprising a flexible carrier for wearing
by a user, a watertight sealed pouch mounted into said carrier so
as to cover a portion of the user's body, a compacted stack of substantially
vertical layers of flexible woven ballistic material mounted into
said pouch, a desiccant mounted into said pouch wherein said desiccant
reduces a humidity level within said pouch and said compacted stack:
2. The ballistic body armor of claim 1 wherein said desiccant is
at least one desiccant impregnated sheet.
3. The ballistic body armor of claim 1 wherein said ballistic material
is PBO.
4. The ballistic body armor of claim 2 wherein said ballistic material
is PBO.
5. The ballistic body armor of claim 3 wherein said desiccant is
at least one desiccant impregnated sheet.
6. The ballistic body armor of claim 2 wherein said sheet is interleaved
between layers of said stack.
7. The ballistic body armor of claim 5 wherein said sheet is interleaved
between layers of said stack.
8. The ballistic body armor of claim 2 wherein said sheet is sandwiched
between said stack and a wall of said pouch.
9. The ballistic body armor of claim 1 wherein said desiccant is
a plurality of sheets impregnated with a desiccant means, and wherein
said plurality of sheets are interleaved with or snugly adjacent
to said stack.
10. The ballistic body armor of claim 1 wherein said plurality
of sheets are co-extensive with said layers in said stack.
11. Ballistic body armor system for reducing humidity in sealed
flexible body armor comprising a flexible carrier for wearing by
a user, a watertight sealed pouch mountable into said carrier so
as to cover a portion of the user's body, a stack of substantially
vertical layers of flexible woven ballistic material mountable into
said pouch, a desiccant mountable into said pouch distributed uniformly
across said stack, wherein said desiccant reduces a humidity level
within said pouch and said stack.
12. The ballistic body armor of claim 11 wherein said desiccant
is at least one desiccant impregnated sheet.
13. The ballistic body armor of claim 11 wherein said ballistic
material is PBO.
14. The ballistic body armor of claim 12 wherein said ballistic
material is PBO.
15. The ballistic body armor of claim 13 wherein said desiccant
is at least one desiccant impregnated sheet.
16. The ballistic body armor of claim 12 wherein said sheet when
mounted in said stack is interleaved between layers of said stack
so as to be co-extensive with said layers in said pouch.
17. The ballistic body armor of claim 15 wherein said sheet is
interleaved between layers of said stack so as to be co extensive
with said layers in said pouch.
18. The ballistic body armor of claim 12 wherein said sheet when
mounted in said pouch is sandwiched between said stack and a wall
of said pouch and is co-extensive with an outermost layer of said
stack.
19. The ballistic body armor of claim 11 wherein said desiccant
is a plurality of sheets impregnated with a desiccant means, and
wherein said plurality of sheets when mounted in said pouch are
interleaved with or snugly adjacent to said stack.
20. The ballistic body armor of claim 11 wherein said plurality
of sheets when mounted in said pouch are co-extensive with said
layers in said stack.
Description CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Provisional Patent
Application No. 60/362067 filed Mar. 7 2003 entitled Combination
Desiccant and Ballistic Material in Ballistic Body Armor.
BACKGROUND OF INVENTION
[0002] This invention relates to the field of body armor and in
particular to the use of a desiccant in combination with the ballistic
material of body armor in order to maintain humidity in the body
armor beneath performance reducing levels.
[0003] P-phenylene-26-benzobisoxazole, referred to herein and
by one manufacturer, Toyobo Co., Ltd. of Osaka, Japan, by the acronym
PBO and sold by that manufacturer under the trademark Zylon, is
advertised as a rigid-rod lyotropic liquid crystal polymer having
tensile strength and modulus superior to P-Aramid fibres, and as
exhibiting outstanding high flame resistance and thermal stability
among organic fibres. In applicant's experience, use of Zylon.TM.
in ballistic body armor may provide up to approximately thirty percent
better performance as compared to, for example, older aramid ballistic
materials. Zylon.TM. is thus now a commonly used ballistic material
in body armor design because of its improved performance to protect
against penetration by ballistic projectiles such as bullets. However,
it is now been identified that Zylon.TM. degrades under combined
high heat and high humidity conditions so as to adversely affect
its ballistic performance. The degradation is not, as far as applicant
is aware, the impermanent performance degradation such as has been
previously identified due to moisture in the use Kevlar.TM. woven
aramid fibre cloth, but rather results in permanent degradation
of the ballistic material performance. In applicant's experience,
and in applicant's prior art designs such as sold by Pacific Safety
Products of Kelowna, British Columbia, Canada, applicant and other
designers of ballistic armor take extreme care in the design of,
and rigorously test, any changes to the order, number and composition
of the layers of material found with ballistic body armor. A user's
life may depend on it. Consequently, the introduction by a person
skilled in the art of flexible ballistic body armor of a substance
or layer into the ballistic material layers which is foreign to
conventional substances or layers conventionally found in ballistic
body armor is in applicant's experience rarely done. Changes and
modifications are only very conservatively implemented to avoid
chances of unforeseen adverse consequences to the ballistic performance
of the layers of ballistic material whether they be woven aramid
fibre layers or the PBO layers which are the subject of the present
invention. Applicant's invention is thus unconventional in that
at least one layer of a foreign desiccant substance, for example
at least one layer of desiccant sheet is interleaved, sandwiching,
or sandwiched between the layers of conventional PBO ballistic material
in flexible ballistic body armor. It is an object of the present
invention to introduce a desiccant into ballistic body armor employing
PBO fibre ballistic body armor so as to inhibit permanent performance
degradation of the material's ballistic penetration resistance due
to moisture within the body armor. In the prior art, applicant is
aware of patents disclosing the use of moisture control materials
in protective clothing for the purposes of the comfort of the wearer.
In particular, applicant is aware of patents which disclose the
use of wicking and other materials to transfer, evaporate or absorb
moisture within the garment, as for example found disclosed in U.S.
Pat. No. 6044498 which issued to Schumann et al. on Apr. 4 2000
for Slash and Cut Resistant Garments for Protecting a Person From
Injury, U.S. Pat. No. 5471906 which issued Bachner, Jr. et al.
on Dec. 5 1995 for a Body Armor Cover and Method for Making the
Same, U.S. Pat. No. 5327811 which issued to Price et al. on Jul.
12 1994 for a Lightweight Ballistic Protective Device, U.S. Pat.
No. 5472769 which issued to Goerz, Jr. et al. on Dec. 5 1995
for a Soft Body Armor Material with Enhanced Puncture Resistance
Comprising at Least One Continuous Fabric Having Knit Portions and
Integrally Woven Hinge Portions, U.S. Pat. No. 6233737 which issued
to Ditchfield et al. on May 22 2001 for a Concealable Ballistic
Vest and U.S. Pat. No. 6138277 which issued to Gillen et al. on
Oct. 31 2000 for a Protective Body Vest. The moisture control in
this prior art generally involves the use of fabric layers for example
the moisture absorbing inner layer of Goerz, Jr., or the vapour
permeable cover layer over the flexible armor plating layer of Bachner,
Jr. et al. Similarly, in the prior art applicant is also aware of
a Korean Patent, Patent No. KR 2001 01 7116 which issued to Lee
for a Bulletproof Vest Having Air Ventilation Property and which
discloses the use within a bulletproof vest of inner covers of foamed
polyethylene material providing such an air ventilation property
so that sweat moisture is transferred from the body of the user
to a moisture absorbing fibre positioned inside an outer cover.
SUMMARY OF INVENTION
[0004] The present invention is ballistic body armor wherein sheets
of ballistic material such as PBO are contained in a layered stack
within a sealed watertight pouch mounted or mountable into a flexible
carrier for wear by a user. The pouch is sealed so that whatever
ambient humidity is introduced into the pouch during manufacturing
remains the maximum ambient humidity. A desiccant and desiccant
storage means, for example desiccant impregnated sheets of paper,
are contained within the pouch. The desiccant sheets may form inter-leaved
layers within the stack of layers of ballistic material or may sandwich
the stack, or may be a single sheet which may be sandwiched within
the stack or otherwise inserted anywhere into the pouch. The desiccant
removes or reduces humidity levels within the pouch to such low
levels as to remain below humidity levels which, in combination
with high heat, would permanently degrade the performance of PBO
fibres making up the layers of ballistic material.
[0005] It is intended to be within the scope of the present invention
to introduce desiccant by a storage and delivery means, such as
a matrix or sheet impregnated with a desiccant chemical composition,
into a sealed pouch containing layers of ballistic material such
as PBO whose ballistic performance degrades due to high humidity
so as to inhibit high humidity induced ballistic performance degradation
of the ballistic material within the pouch. The pouch is for mounting
into ballistic body armor.
[0006] In summary then, the ballistic body armor and dehumidification
system according to the present invention includes a flexible carrier
for wearing by a user. The carrier contains a watertight sealed
pouch. The pouch contains a stack of layers of ballistic material,
such as PBO, whose performance degrades under certain conditions
in the presence of moisture, and a desiccant. The watertight sealed
pouch is mounted into the carrier so as to cover a portion of the
user's body when the user is wearing the body armor. When the armor
is worn by the user, the stack is a stack of substantially vertical
layers of flexible ballistic material mounted into the pouch. The
desiccant is mounted into the pouch. Because of the wicking effect
or aerating effect of the porous weave of the ballistic material,
the desiccant may be placed anywhere within the pouch and its effect
is distributed uniformly across the stack, to uniformly reduce a
humidity level within the pouch and the stack. The desiccant and
the nature of woven ballistic material cooperate so that a small
amount, such as a small sheet of a desiccant impregnated flexible
matrix simply placed anywhere in the pouch will have a far-reaching
dehumidification effect on the conventionally closely compacted
stack of layers of ballistic material The desiccant sheet may be
interleaved between layers of the stack or may be partially co-extensive
with the layers in the pouch, and/or sandwiched between the stack
and a wall of the pouch and may be partially co-extensive with an
outermost layer of the stack. The desiccant may be a matrix other
than a sheet or may be a plurality of carrier sheets impregnated
with a desiccant means such as a desiccant chemical composition,
wherein the plurality of sheets are interleaved with or snugly adjacent
to the stack, again, for example, at least partially co-extensive
with the layers in the stack.
BRIEF DESCRIPTION OF DRAWINGS
[0007] FIG. 1 is, in elevation view, the front and back panel of
one form of body armor incorporating the present invention laid
flat, the armor casing partially cut away.
[0008] FIG. 2 is, in partially cut away elevation view, a water
impervious pouch containing sheets of ballistic material and desiccant
for mounting into the body armor of FIG. 1.
[0009] FIG. 3 is a sectional view along line 3-3 in FIG. 2.
DETAILED DESCRIPTION
[0010] With reference to the drawings, wherein similar characters
of reference denote corresponding parts in each view, as seen in
FIGS. 1-3 ballistic body armor 10 may include front and back panels
12 and 14 respectively. Each of the panels may have an outer fabric
casing or carrier 16 for example sewn around the panel's circumferential
edges so as to define in combination with the assembled front and
back panels, side arm openings and an upper neck opening for the
user. Within each of the panels, and retained snugly and conformally
so as to correspond to the profiled outline of each panel, is a
sealed water impermeable pouch 18 for example, a heat sealed plastic
pouch.
[0011] Each pouch is sealed contiguously around its perimeter so
as to define a cavity 20 within the pouch. The cavity is generally
planar when the pouch is laid flat. A stack of adjacently layered
generally parallel sheets of Zylon.TM. PBO fibre material 22 are
snugly mounted within pouch 18 so as to maintain sheets 22 generally
parallel and compactly sandwiched between front and back faces 18a
and 18b respectively of pouch 18.
[0012] Pouch 18 contains at least one flexible sheet 24 impregnated
with a desiccant such as Drikette Desiccant Paper, sold by S &
D Chemical of Scarborough, Ontario, Canada, and manufactured by
Multisorb Technologies Inc. of Buffalo, N.Y., United States. Such
desiccant paper may absorb up to three hundred times its weight
in moisture. Sheets 24 may be desiccant impregnated paper sheets,
but it is not intended to be limiting as many desiccant storage
and delivery means would work to introduce the desiccant and uniformly
dehumidify a stack of sheets 22 within sealed pouch 18 so as to
reduce humidity levels within the pouch. The use of desiccant sheets
may provide the advantage of a consistent, structurally stable and
uniform distribution of the desiccant across, that is parallel to,
at least a portion of the surface area of the pouch which would
be exposed to penetration by ballistic projectiles. Uniform distribution
of the effect of the desiccant, which remains constantly uniform
in cooperation with the wicking or porous nature of the weave of
woven ballistic material such as PBO ballistic material offers the
advantage of uniform humidity control across the pouch no matter
where the desiccant is mounted, so long as exposed to the ballistic
material in the pouch, which may be relied on for the operative
life of the armor, minimizing the risk of isolated areas of higher
humidity within the distributed volume of the cavity within the
pouch.
[0013] As will be apparent to those skilled in the art in the light
of the foregoing disclosure, many alterations and modificaare possible
in the practice of this invention without departing from the spirit
or scope thereof. Accordingly, the scope of the invention is to
be construed in accordance with the substance defined by the following
claims. |