U.S. patent number 3,873,998 [Application Number 05/454,897] was granted by the patent office on 1975-04-01 for body armor system.
This patent grant is currently assigned to The United States of America as represented by the Secretary of the Army. Invention is credited to Philip E. Durand, Lonnie H. Norris.
United States Patent |
3,873,998 |
Norris , et al. |
April 1, 1975 |
BODY ARMOR SYSTEM
Abstract
A coordinated missile- and fragmentation- protective body armor
system coising a ceramic type armor plate component that is
provided with a spall shield made of a plurality of layers of
ballistic fabric and a spacer container for the ceramic armor plate
made of a foamed plastic. The spacer container, though of little
value for stopping primary missiles, is very effective in
combination with the spall shield in preventing the escape from the
body armor system of spall from the ceramic armor plate.
Inventors: |
Norris; Lonnie H. (Milford,
MA), Durand; Philip E. (Hudson, MA) |
Assignee: |
The United States of America as
represented by the Secretary of the Army (Washington,
DC)
|
Family
ID: |
23806516 |
Appl.
No.: |
05/454,897 |
Filed: |
March 26, 1974 |
Current U.S.
Class: |
2/2.5;
D29/101.3 |
Current CPC
Class: |
B32B
7/12 (20130101); F41H 1/02 (20130101); B32B
27/12 (20130101); B32B 9/00 (20130101); B32B
17/061 (20130101); B32B 15/08 (20130101); B32B
2323/04 (20130101); B32B 2315/02 (20130101); B32B
2325/00 (20130101) |
Current International
Class: |
B32B
9/00 (20060101); F41H 1/00 (20060101); F41H
1/02 (20060101); F41h 001/02 () |
Field of
Search: |
;2/2.5 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Guest; Alfred R.
Attorney, Agent or Firm: Edelberg; Nathan Gibson; Robert P.
Rainey; Charles C.
Claims
We claim:
1. A coordinated protective body armor system to provide protection
against low caliber missiles which will also minimize escape of
spall from within said system, cushion the brittle elements of the
system against breakage, and provide cushioning protection to
protect the head and neck of the wearer from injury upon impact
against the armor system comprising a ceramic/fiber glass composite
armor plate which comprises a ceramic face plate bonded to laminate
back plate of resin-bonded plies of a glass fiber fabric, a foamed
plastic spall protective container for said ceramic/ fiber glass
composite armor plate which is disposed so as to completely cover
said ceramic/fiber glass composite armor plate, and a carrier for
said ceramic/fiber glass composite armor plate and said foamed
plastic spall protective container comprising a spall shield which
overlies said foamed plastic spall protective container and said
ceramic/fiber glass composite armor plate and which comprises a
plurality of plies of a woven ballistic fabric.
2. A coordinated protective body armor system according to claim 1,
wherein said foamed plastic spall protective container is formed of
polymeric foam having a density of from about 1 to about 10 pounds
per cubic foot.
3. A coordinated protective body armor system according to claim 2,
wherein said foamed plastic spall protective container is formed of
polyethylene foam having a density of about 9 pounds per cubic
foot.
4. A coordinated protective body armor system according to claim 1,
wherein said foamed plastic spall protective container in the
portion thereof which completely covers said ceramic/fiber glass
composite armor plate is from about 1/2 inch to about 3/4 inch
thick.
5. A coordinated protective body armor system according to claim 1,
wherein said woven ballistic fabric is a plain weave nylon fabric
weighing from about 6 to about 9 ounces per square yard.
6. A coordinated protective body armor system according to claim 1,
wherein said spall shield comprises nine plies of ballistic nylon
fabric weighing about 7.5 ounces per square yard.
7. A coordinated protective body armor system according to claim 1,
wherein said fabric carrier comprises means for detachably
suspending said fabric carrier in proximity to the front of the
torso of said wearer.
Description
The invention described herein may be manufactured, used, and
licensed by or for the Government for governmental purposes without
the payment to us of any royalty thereon.
BACKGROUND OF THE INVENTION
This invention relates to a coordinated missile- and
fragmentation-protective body armor system wherein lightweight
means are provided for markedly reducing or preventing the escape
of spall from a ceramic type armor plate component of the body
armor and thereby greatly reducing the probability of injury to
others in the vicinity of the wearer of the body armor when it is
impacted by high velocity projectiles, shell fragments, or other
particles.
In recent years body armor comprising ceramic armor plates to
protect the torso of the wearer against serious or fatal injury to
the vital organs has been developed to the point that good
protection is obtained against low caliber missiles, such as
missiles of up to .30 caliber, and effective protection is obtained
against shell fragments and the like. However, this type of armor
plate is prone to fragment, i.e., to produce spall, when struck by
a high velocity missile or fragment. The spall thus produced as a
spray of secondary particles of varying sizes and shapes may have
very high velocities imparted to the particles by absorption of
energy from the primary projectile or fragment. Such spall, if
permitted to escape from the proximity of the ceramic armor plate
and the fabric carrier therefor, is capable of causing severe
injury to eyes or other portions of the bodies of other nearby
persons.
It is therefore, an object of the invention to provide a body armor
system which is not only effective in protecting the wearer
thereof, particularly in the region of the torso, against low
caliber missiles, i.e., missiles of up to about .30 caliber, and
against shell fragments, shrapnel and the like, but also
effectively prevents the escape of spall from the system,
particularly the spall produced from a ceramic armor plate element
of the armor system. Another object of the invention is to provide
a body armor system comprising a ceramic armor plate and having
means for preventing injury to the neck, chin or face of the wearer
of the body armor system in the event that the ceramic armor plate
impacts those portions of the body of the wearer if the wearer is
involved in a crash or other incident in which his body comes to an
abrupt halt or is subjected to sudden deceleration. A further
object of the invention is to provide a body/armor system
comprising a ceramic armor plate and having means for preventing or
minimizing breakage or cracking of the ceramic armor plate in case
the body armor system is dropped upon a hard surface.
Other objects and advantages of the invention will be apparent from
the following description of one embodiment of the invention, and
the novel features will be particularly pointed out hereinafter in
connection with the appended claims.
SUMMARY
The objects of the invention are accomplished by providing a
coordinated body armor system which comprises a ceramic/fiber glass
composite armor plate, a fabric carrier therefor comprising a
plurality of plies of ballistic fabric and a foamed plastic spall
protective spacer container for the armor plate. The foamed plastic
spall protective spacer container spaces the armor plate from the
plies of ballistic fabric in the fabric carrier a distance which
has been found to greatly assist in and augment the slowing down of
the spall from the point of impact of a missile or fragment on the
ceramic armor plate. Additionally, the foamed plastic spacer
container is provided with shock absorbent side edges which overlap
the edges of the armor plate and thus provide edge protection for
the armor plate against breakage or cracking if it is dropped. The
shock absorbent side edges also provide protection against injury
to the neck or chin or face of the wearer by the upper edge of the
armor plate in case the latter shifts upwardly at a velocity which
would otherwise injure the neck, chin or face of the wearer, or in
case the head of the wearer is suddenly caused to pivot in the
direction of the armor plate. The fabric carrier for the armor
plate is provided on an outer surface thereof with means for
attaching the fabric carrier to the jacket of the wearer so that
the body armor system may be supported in fromt of the torso of the
wearer.
Thus the components of the body armor system of the invention are
coordinated to perform a variety of highly useful and desirable
functions in protecting the wearer thereof as well as persons in
close proximity to the wearer and in being protected from
inadvertent damage in the handling of the same.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of the foamed plastic spall protective
spacer container viewed from the rear thereof, the spacer container
having a curvature approximating the curvature of the front of the
torso of a wearer of body armor, the rear of the spacer container,
when being worn, being oriented toward the front of the torso of
the wearer.
FIG. 2 is a perspective view of a ceramic/fiber glass composite
armor plate.
FIG. 3 is a perspective view of a fabric carrier for the ceramic/
fiber glass composite armor plate.
FIG. 4 is a perspective view of the foamed plastic spall protective
spacer container of FIG. 1 with the ceramic/fiber glass composite
armor plate of FIG. 2 inserted therein preparatory to the insertion
of the spacer container containing the ceramic/fiber glass
composite armor plate in the fabric carrier of FIG. 3.
FIG. 5 is a perspective view from the rear of the assembled armor
system after insertion of the spacer container containing the
ceramic/fiber glass composite armor plate in the fabric carrier and
closure of the fabric carrier.
FIG. 6 is a perspective view from the front of the assembled armor
system of FIG. 5.
FIG. 7 is a vertical cross-section of the assembled armor system of
FIG. 5 taken along a plane through the line 7--7 of FIG. 5.
FIG. 8 is a horizontal cross-section of the assembled armor system
of FIG. 5 taken along a plane through the line 8--8 of FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
Body armor developed in recent years for use by members of the
Armed Forces for protection of their torsos and vital organs
against low caliber missiles and shell fragments comprises a
ceramic/fiber glass composite armor plate, such as the armor system
described in U.S. Pat. No. 3,557,384. In such body armor the facing
or outward component is a onepiece aluminum oxide, silicon carbide,
or boron carbide ceramic structure bonded by an adhesive to a
resin-bonded ballistic fabric laminate back plate which is
preferably a fiber glass fabric laminate. The fiber glass fabric
laminate is a resin-impregnated, multi-layer, fiber glass ballistic
fabric with the resin content being in the range of 20% to 30% by
weight. The maximum areal density of this type of armor plate is
less than 9 lbs. per square foot and preferably less than 7 lbs.
per square foot. Because of the weight of this armor material, the
body area being protected must be reduced to the absolute minimum.
Therefore, the armor plates are designed to cover the more
vulnerable portions of the torso. The body armor may be worn inside
of a jacket or other outer garment which may or may not be
constructed of or comprise ballistic materials or spall protective
materials.
The present invention provides a spacer container made of a
light-weight material, such as foamed plastic, which has the
capability of slowing down the spall produced when high velocity
projectiles or shell fragments strike the ceramic outward surface
of the armor plate, thus enabling a plurality of layers of a
ballistic fabric, e.g., ballistic nylon woven fabric, incorporated
in a carrier for the body armor outside of the spacer container to
further reduce the velocity of the spall and in most instances
completely prevent escape of the spall from the carrier. Thus a
coordinated missile- and fragmentation- protective body armor
system which is of relatively light weight yet quite effective
against low caliber, high velocity missiles as well as spall
produced thereby is obtained. The spacer container also serves
other purposes which will be more particularly described
hereinafter.
The spacer container 10 illustrated in FIG. 1 is molded in one
piece out of foamable plastic such as polyethylene, polystyrene, or
other polymeric materials which are capable of being foamed in
place in a mold, or may be machined from a block of foamed plastic.
It is formed with a recess 13 or hollow opening corresponding very
closely to the size, outline shape, and curvature of armor plate 11
shown in FIG. 2 so that the latter can be fitted snugly in recess
13, as shown in FIG. 4, with the rear face of the armor plate flush
with the top of the flanged edge 14 of the spacer container. Thus
the armor plate is recessed within the spacer container so that a
thickness of from about 1/2 inch to about 3/4 inch of the foamed
plastic of the spacer container overlies the ceramic armor plate 17
of armor plate 11. It has been found to be preferable for the
portion of the spacer container overlying the ceramic armor plate
to be about 1/2 inch thick. The top edge 15 of the spacer container
flanged portion is about one inch thick from top to bottom and is
approximately twice the thickness of the flanged edge 14 measured
from one side edge to the other and twice the thickness of the
extension thereof along the bottom edge of the spacer container in
the form of flanged edge 16 so that there will be appreciable
cushioning of the neck and chin or other portions of the face or
head of the wearer of the body armor in the event that the wearer
is involved in a crash or is abruptly decelerated while in motion.
Under such circumstances the armor plate 11, which is rather heavy,
would tend to continue in motion and, in the absence of the
relatively thick top edge 15 of the spacer container, would impact
with great force against the neck or chin of the wearer or possibly
against other portions of the face or head. Thus the spacer
container made of a crushable foamed plastic serves to protect the
wearer against serious injury by the armor plate.
As previously stated, armor plate 11 fits a recess 13 of spacer
container 10, as shown in FIG. 4. The spacer container, together
with the armor plate, is placed inside of fabric carrier 12, which
has a body portion 19 and a closure flap 20. Along the bottom edge
of the back of the body portion 19 the fabric carrier has a strip
of plastic loops 21 which cooperate with a strip of plastic hooks
22 attached to the inner surface of closure flap 20 to close the
opening along the bottom edge of the fabric carrier through which
the armor plate is inserted into the fabric carrier. The armor
plate is inserted in fabric carrier 12 so that the concavity of the
composite structure will be up as seen in the drawing and will be
oriented toward the torso of the wearer of the body armor when
being worn. Thus the ceramic armor plate 17 will be oriented away
from the torso of the wearer.
As shown in FIG. 6, the front of the fabric carrier 12 has zipper
stringers 23 and 24 attached thereto for the purpose of attaching
the assembled armor system to the inside surface of a combat jacket
or other type of garment with which the body armor is worn to
protect the torso of a wearer. The jacket (not shown) has a pair of
suitably spaced zipper stringers (not shown) which cooperate with
zipper stringers 23 and 24 with the combined action of slider 25 on
stringer 24 and a similar slider on the stringer of the jacket
which cooperates with stringer 23. Thus the assembled armor system,
being supported by two spaced apart zippers joining the fabric
carrier to the jacket is maintained in reasonably stable position
in front of the torso of the wearer, protecting the same against
low caliber missiles and shell fragments.
As seen in FIGS. 7 and 8, the assembled armor system comprises a
spall shield 27 made of plies of ballistic fabric, ceramic armor
plate 17, fiber glass laminate backup layer 18, foamed plastic
spacer container 10, and fabric carrier 12. The innermost layer 26,
i.e., the layer which is worn closest to the torso of the wearer,
is a single thickness of ballistic fabric, preferably nylon
ballistic cloth such as that described in military specification
MIL-C-12369D (GL) entitled "Cloth, Ballistic, Nylon." This layer of
ballistic cloth is also the outermost layer of spall shield 27,
which is a nine-layer composite of nylon ballistic cloth of the
type described in the above-referenced military specification. The
spall shield 27 extends over the top, sides, front, and bottom of
fabric carrier 12, thus providing spall protection across the top,
sides, front, and bottom of armor plate 11. The outermost layer of
spall shield 27, which is a continuation of innermost layer 26 of
fabric carrier 12 extends upwardly from the bottom of the fabric
carrier to form closure flap 20. The nine layers of nylon ballistic
cloth are stitched together along their peripheries, but remain as
separate, unattached fabrics over most of their surfaces so that
they are more or less free to move and adjust to the impact of a
particle and thus to perform well as a spall shield. The plastic
hooks 22 and plastic loops 21 mate to form hook and pile fastener
28 which maintains the fabric carrier closed.
Next to the innermost layer 26 progressing outwardly therefrom and
from the torso of the wearer is the fiber glass laminate backup
layer 18, which backs up the ceramic armor plate 17 and is bonded
thereto. After the ceramic armor plate comes the spacer container
10 made of foamed, plastic, which because of its thickness spaces
the ceramic armor plate about 1/2 to 3/4 inch from the spall shield
27 and thus contributes materially to the prevention of the escape
of spall from the ceramic armor plate when the latter is impacted
by a missile or shell fragment.
The spacer container has relatively low stopping power for primary
missiles, but is quite effective against the spall from the ceramic
armor plate since the cooperation thereof with the spall shield
practically prevents all escape of spall from the ceramic armor
plate. The ceramic armor plate serves as the main stopping agent
for the primary missiles, though the spall shield slows the primary
missiles down considerably before they impact the ceramic armor
plate. Spacing of the spall shield from the ceramic armor plate
influences spall resistance because spall travels in a conical
pattern radiating from the point of impact with the ceramic armor
plate. Thus, spacing causes the spall to impact the spall shield
over a broader area, producing less concentration of force per unit
area. Consequently, the spall shield can better sustain the forces
of the spall. In addition, spacing requires the typical spall
particle traveling at oblique angles to traverse a greater distance
than the thickness of the spacing and to dissipate more energy
before impacting the spall shield overlying the spacing.
The fiber glass laminate backup layer 18 serves to augment the
stopping power of the ceramic armor plate and to complete the
defeat of the primary missiles if any penetrate the ceramic armor
plate.
The overall result is a coordinated missile- and fragmentation-
protective body armor system which is relatively light in weight
yet very effective in defeating primary missiles of low caliber and
in preventing the escape of spall from a ceramic armor plate
component of the body armor system which serves as the main
protective medium against the primary missiles.
We have found it to be preferable that the foamed plastic of the
spacer container have a density of from about 1 pound per cubic
foot to about 10 pounds per cubic foot. Foamed polyethylene of
approximately 9 pounds per cubic foot, for example "Ethafoam,"
fabricated by United Packaging Corp., Georgetown, Mass., has been
found to be particularly effective for all three of the purposes
served by the spacer container, i.e., assisting in the prevention
of the escape of spall derived from the ceramic armor plate,
protecting the neck, chin, and other portions of the face and head
of the wearer of the body armor from serious injury upon impact
against the ceramic armor plate, and protecting the ceramic armor
plate against cracking or shattering due to dropping thereof onto a
non-resilient surface or bumping of the armor by sharp,
non-resilient objects. Furthermore, the resiliency of the
polyethylene foam spacer container permits repetitive use, whereas
some foamed plastics, such as polystyrene, have very good shock
absorbing capacities even at quite low densities, but are
permanently crushed and, therefore, not effective for repetitive
use.
It is preferred that the nylon ballistic cloth of the spall shield
and the fabric carrier be a plain weave fabric of about 7.5 ounces
per square yard. However, other nylon ballistic fabrics,
particularly those of from about 6 to about 9 ounces per square
yard may be employed with good results as spall shield
material.
The coordinated missile- and fragmentation- protective body armor
system of the invention is very effective in an areal density of
about 0.83 pounds per square foot in protecting the torso of the
wearer against low caliber missiles and in preventing the escape of
spall from the system. It has been found that about 1.0 pound per
square foot areal density is about the upper limit for a useful
body armor system. The system of the present invention falls well
below this limit while accomplishing excellent spall
suppression.
The invention has been described in terms of a particular type of
coordinated missile- and fragmentation- protective body armor
system. A particularly important element of this system is the
foamed plastic spall protective spacer container for the ceramic
armor plate. The spacer container may be constructed of a rather
large number of different foamed plastic materials. These materials
need to be crushable, but neither too easily crushable nor too
difficult to crush, since in the coordinated armor system they need
to be able to prevent injury to the neck or chin or other portions
of the face or head of the wearer by absorbing energy through
crushing in case the armor plate impacts portions of the head or
neck; and they also need to be able to prevent damage to the armor
plate in case it is dropped or struck by a sharp, non-resiliant
object. Hence, the spacer container material must have the proper
crushability characteristics in order to be shock-absorbent for the
two purposes mentioned. Furthermore, the density and thickness of
the spacer container material must be such as to cause spall from
the ceramic armor plate to be slowed down by the combination of the
spacer container and the ballistic fabric spall shield used in
combination with the armor plate sufficiently to prevent escape of
the spall and the possible inflicting of injury to persons in close
proximity to the wearer of the armor system. The corrdinated system
of the present invention accomplishes all of these objectives while
having a tolerable weight when fabricated so as to cover and
protect the more vital areas of the torso of a wearer of the body
armor system.
It will be understood that various changes in the details,
materials, and arrangements of parts, which have been herein
described and illustrated in order to explain the nature of the
invention, may be made by those skilled in the art, within the
principle and scope of the invention as expressed in the appended
claims.
* * * * *