U.S. patent application number 14/590101 was filed with the patent office on 2015-05-07 for helmet designs utilizing foam structures having graded properties.
The applicant listed for this patent is KineticShield, Inc.. Invention is credited to Alan Ira FADEN, Thomas E. TWARDOWSKI, JR..
Application Number | 20150125663 14/590101 |
Document ID | / |
Family ID | 46635713 |
Filed Date | 2015-05-07 |
United States Patent
Application |
20150125663 |
Kind Code |
A1 |
FADEN; Alan Ira ; et
al. |
May 7, 2015 |
HELMET DESIGNS UTILIZING FOAM STRUCTURES HAVING GRADED
PROPERTIES
Abstract
Disclosed herein is a composite structure for deflecting and
spreading kinetic energy transmission after various types of
impacts utilizing foam structures having graded properties. The
structure has a first composite layer, composed of a discrete
reinforcement and a continuous binder. The helmet receives contact
of an object that transfers kinetic energy to a first composite
layer. The helmet uses a second composite layer adjacent to the
first composite layer designed such that the second composite layer
compresses and expands into an expansion zone in the second
composite layer. The second composite layer has expansion
structures with a graded modulus such that the material at the tip
of an expansion structure has a low modulus and the modulus in the
expansion structure increases as it moves from the tip to the base
of the expansion structure.
Inventors: |
FADEN; Alan Ira; (Baltimore,
MD) ; TWARDOWSKI, JR.; Thomas E.; (Morrisville,
PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KineticShield, Inc. |
Doylestown |
PA |
US |
|
|
Family ID: |
46635713 |
Appl. No.: |
14/590101 |
Filed: |
January 6, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13267551 |
Oct 6, 2011 |
8927088 |
|
|
14590101 |
|
|
|
|
61442469 |
Feb 14, 2011 |
|
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Current U.S.
Class: |
428/160 |
Current CPC
Class: |
A42B 3/063 20130101;
B32B 2264/12 20130101; F41H 5/007 20130101; Y10T 428/24661
20150115; B32B 2260/046 20130101; Y10T 442/637 20150401; B32B 5/22
20130101; F41H 1/08 20130101; Y10T 428/24562 20150115; B32B 5/16
20130101; B32B 5/145 20130101; B32B 2419/00 20130101; B32B 5/30
20130101; B32B 2437/04 20130101; Y10T 428/24992 20150115; A42B
3/064 20130101; B32B 2260/025 20130101; Y10T 428/24 20150115; B32B
7/02 20130101; Y10T 428/252 20150115; F41H 1/04 20130101; B32B
2605/00 20130101; B32B 1/00 20130101; B32B 2264/101 20130101; F41H
5/0492 20130101; B32B 2264/107 20130101; B32B 2571/00 20130101;
B32B 2307/56 20130101; B32B 2264/10 20130101; Y10T 428/24512
20150115; Y10T 428/31678 20150401; Y10T 428/1334 20150115; B32B
27/20 20130101; B32B 3/08 20130101; Y10T 442/637 20150401; C08L
23/02 20130101; Y10T 428/24983 20150115; B32B 3/26 20130101; F41H
5/0428 20130101; A43B 13/189 20130101; A44B 18/0076 20130101; B32B
3/12 20130101; Y10T 428/25 20150115; B32B 2262/10 20130101; A41D
31/285 20190201; Y10T 428/1334 20150115; Y10T 428/24612 20150115;
Y10T 428/31504 20150401 |
Class at
Publication: |
428/160 |
International
Class: |
A42B 3/06 20060101
A42B003/06; B32B 3/08 20060101 B32B003/08; B32B 5/14 20060101
B32B005/14; A41D 31/00 20060101 A41D031/00 |
Claims
1. A structure for reducing kinetic energy transmission, the
structure comprising: a first composite layer configured as an
outside layer that serves as first contact with a source of kinetic
energy; and a second composite layer, adjacent to the first
composite layer comprising a first plurality of expansion
structures in which each expansion structure of the first plurality
of expansion structures has a base configured adjacent to the first
composite layer and each expansion structure having a first tip,
and a second plurality of expansion structures configured such that
a respective second tip of each expansion structure of the second
plurality of expansion structures is in contact with the first tip
of a corresponding expansion structure of the first plurality of
expansion structures in a mirrored configuration, such that when
the source comes in contact with the first composite layer, the
second composite layer compresses and at least one expansion
structure of the first plurality of expansion structures and the
second plurality of expansion structures expands into an expansion
zone in the second composite layer.
2. The structure of claim 1, wherein the first composite layer
comprises a composite of at least two materials.
3. The structure of claim 2, wherein the composite has a polymer
matrix and a ceramic reinforcement.
4. The structure of claim 2, wherein the composite has a polymer
matrix and a glass reinforcement.
5. The structure of claim 3, wherein the ceramic reinforcement is a
fiber.
6. The structure of claim 1, wherein the second composite layer
comprises material that deforms under impact to transfer kinetic
energy.
7. The structure of claim 1, wherein the first plurality of
expansion structures and the second plurality of expansion
structures each comprises expansion structures having a graded
modulus.
8. The structure of claim 7, wherein the graded modulus comprises
material at the tip of the expansion structure having a low modulus
and the modulus in each expansion structure increasing as it moves
from the tip to the base of each expansion structure.
9. The structure of claim 7, wherein the graded modulus comprises
material at the tip of the expansion structure having a high
modulus and the modulus in each expansion structure decreasing as
it moves from the tip to the base of each expansion structure.
10. The structure of claim 1, wherein the expansion structures are
comprised of flexible foam.
11. The structure of claim 10, wherein the foam is comprised of
polyurethane.
12. The structure of claim 1, wherein each expansion structure in
the first plurality of expansion structures has one of the same
shape or a different shape.
13. The structure of claim 1, wherein each structure of the first
plurality of expansion structures differs in shape from each
structure of the second plurality of expansion structures.
Description
PRIORITY
[0001] The present application is a continuation of U.S. patent
application Ser. No. 13/267,551, filed Oct. 6, 2011, which claims
priority to U.S. Provisional Patent Application No. 61/442,469,
filed Feb. 14, 2011, the contents of which are herein incorporated
by reference in their entirety.
BACKGROUND
[0002] 1. Technical Field
[0003] The present disclosure relates to safety helmet design and
more specifically to reducing kinetic energy transmission after
various types of impacts by utilizing foam structures having graded
properties.
[0004] 2. Introduction
[0005] In the United States, hundreds of thousands of people each
year are involved in athletic, cycling or motorcycle accidents
resulting in head injury. Much of the subsequent damage is caused
by the transmission of kinetic energy to the brain, as well as
shear forces. Although existing bicycle helmets reduce deaths and
brain injuries, current designs focus more on aesthetics and
aerodynamic performance than safety, in part due to market demands.
In addition, the helmet industry is essentially self-regulating and
therefore not likely to make significant improvements to helmets
unless the improvements prove to be cost-effective and/or markedly
more effective. Advances in polymeric materials provide novel
approaches to helmet design and construction. Significant
improvements in viscoelastic (active) dampening, low loss
elastomers, and gradient rigidity materials have already given rise
to enhanced athletic equipment and protective gear.
[0006] Crashes and impacts to the head in sports often result in
head trauma due to the rigid construction of helmets. The severe
consequences of concussive brain injuries have become increasingly
recognized in many sports, particularly recently in professional
football and ice hockey. It has also long been recognized that
boxers often suffer significant cognitive decline, even in
non-professional contests where protective head gear is required.
Professional and college sports teams would likely switch to a new
type of helmet, if such a design were clearly shown to reduce
post-traumatic brain injury.
[0007] In addition to athletics, improved helmet designs have
applications in the military. Brain injury is the leading cause of
disability for military personnel deployed in Iraq and Afghanistan.
Although military helmet designs have improved in recent years,
they are intended primarily to prevent missile/shrapnel
penetration, and do little to reduce the energy transmitted to the
brain, which is a major contributor to subsequent disability. The
mechanisms of traumatic brain injury due to blast forces remain
unclear, but brain injuries related to explosives are by far the
most common cause of death and disability in Iraq and Afghanistan.
Experimental evidence indicates that the use of advanced body armor
may contribute to the increase in brain injuries, both by
protecting against death from injury to major non-brain organs such
as the lung, and possibly by transmitting kinetic energy through
larger blood vessels to the brain.
[0008] Existing helmet designs do not adequately address the
critical problem: kinetic energy from the impact is transmitted to
the brain through primary, secondary and tertiary
mechanisms--resulting in concussion, brain damage and even
death.
SUMMARY
[0009] Additional features and advantages of the disclosure will be
set forth in the description which follows, and in part will be
obvious from the description, or can be learned by practice of the
herein disclosed principles. The features and advantages of the
disclosure can be realized and obtained by means of the instruments
and combinations particularly pointed out in the appended claims.
These and other features of the disclosure will become more fully
apparent from the following description and appended claims, or can
be learned by the practice of the principles set forth herein.
[0010] Disclosed is a structure for improved safety helmet design
that reduces both the kinetic energy induced by impact and
rotational forces utilizing foam structures having graded
properties. The safety helmet will better protect the brain by
limiting both direct missile trauma and secondary kinetic effects.
Distributing the force that a penetrating object applies is
typically accomplished by a hard shell. Metals, reinforced Kevlar
or fiberglass composites traditionally have accomplished this role,
but new composites offer improvement. The main failure of most
headgear is that a blunt, distributed force can cause significant
trauma if the force is not dissipated in other ways than
transmission to the skull. The structure disclosed herein
dissipates damaging forces utilizing foam structures having graded
properties. In addition to helmet design, the principles disclosed
herein can also apply to other types of body armor such as chest
protectors and bullet proof vests as well as buildings or other
structures exposed to projectiles or explosives. The layering
approach distributes the forces laterally and away from the skull
based on the structure and interaction between layers in the
structure.
[0011] The safety helmet receives contact of an object that
transfers kinetic energy to a first composite layer and uses a
second composite layer, having a first set of expansion structures
and a second set of expansion structures, adjacent to the first
composite layer designed such that the second composite layer
compresses and at least one expansion structure of the first set of
expansion structures and the second set of expansion structures
expands into an expansion zone in the second composite layer to
transfer kinetic energy laterally with respect to the skull. Each
expansion structure in the first set of expansion structures has a
base configured adjacent to the first composite layer and each
expansion structure has a first tip. The second set of expansion
structures is configured such that a respective second tip of each
expansion structure in the second set of expansion structures is in
contact with the first tip of a corresponding expansion structure
in the first set of expansion structures in a mirrored
configuration.
[0012] Expansion structures in the second composite layer can have
a graded modulus such that material at the tip of the expansion
structure has a low modulus and the modulus in the material
increases as it moves from the tip to the base in an expansion
structure. An expansion structure can have any suitable
compressible material such as foam formulated to have a range of
mechanical compression strength.
[0013] A safety helmet can have any number of composite layers
wherein each composite layer contains a first set of expansion
structures and a second set of expansion structures and at least
one expansion structure compresses and expands into an expansion
zone. Each composite layer can be adjacent to the immediately
preceding layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In order to describe the manner in which the above-recited
and other advantages and features of the disclosure can be
obtained, a more particular description of the principles briefly
described above will be rendered by reference to specific
embodiments thereof which are illustrated in the appended drawings.
Understanding that these drawings depict only exemplary embodiments
of the disclosure and are not therefore to be considered to be
limiting of its scope, the principles herein are described and
explained with additional specificity and detail through the use of
the accompanying drawings in which:
[0015] FIG. 1 illustrates a side view of a safety helmet with
layers utilizing foam structures;
[0016] FIG. 2 illustrates an exemplary safety helmet method
embodiment;
[0017] FIG. 3 illustrates a side view of safety helmet layers
utilizing foam structures having varying sizes;
[0018] FIG. 4 illustrates a side view of safety helmet layers
utilizing foam structures having varying shapes;
[0019] FIG. 5 illustrates an alternate side view of safety helmet
layers utilizing foam structures having varying shapes;
[0020] FIG. 6 illustrates a side view of safety helmet layers
having expansion zones;
[0021] FIG. 7 illustrates a side view of a safety helmet layer
having a compressed expansion structure; and
[0022] FIG. 8 illustrates a side view of a safety helmet having
partially compressed expansion structures.
DETAILED DESCRIPTION
[0023] Various embodiments of the disclosure are discussed in
detail below. While specific implementations are discussed, it
should be understood that this is done for illustration purposes
only. A person skilled in the relevant art will recognize that
other components and configurations may be used without parting
from the spirit and scope of the disclosure.
[0024] The present disclosure addresses the need in the art for
improved safety helmet designs. A safety helmet design is disclosed
that reduces both the kinetic energy induced by impact and
rotational forces. A brief introductory description of safety
helmets is provided followed by a discussion of mathematical
modeling used to optimize helmet layer design. A more detailed
description of improved safety helmet designs utilizing foam
structures having graded properties will then follow. While a
helmet is used in the example embodiment, the layering principles
can also be applied to a wall, body armor, a vehicle, or any
protective layer that could use the principles disclosed herein.
Accordingly, various embodiments of the disclosure include a wall
having a series of layers and disclosed herein, body armor having
the series of layers as well as a vehicle having an outer covering
including the series of layers disclosed herein. The disclosure
proceeds to discuss primarily a helmet embodiment.
[0025] Traditional design for both military and recreational
helmets includes a rigid outer material to prevent penetration of
the skull and brain, as well as some type of lining material to
absorb some of the shock and to enhance comfort. However, few
modern designs adequately address the critical problems leading to
brain damage: kinetic energy transmitted to the brain and rotation
(particularly axial acceleration/deceleration).
[0026] By using novel materials and composites that are organized
upon mathematically defined principles to maximize the relative
dissipation of transmitted kinetic energy, as well as to limit
rotational components, the disclosed design for helmets and body
armor should markedly reduce posttraumatic brain injuries from
various types of insults and impacts. The initial target outcome is
a set of disruptive technological advances in helmet design that
improve the survivability of impact trauma to the head for use in
military and civilian applications.
[0027] Stacks of various materials can be used in experiments to
determine the abilities of the various materials to dissipate and
spread out external forces. Mathematical modeling can be used to
extrapolate from experimental data to the behaviors of actual
helmets constructed of the various material stacks by constructing
local models and constructing local-to-global models.
[0028] A local model refers to a mathematical model of a single
cylindrical stack. Such a model allows calculation, based upon an
exogenous force exerted on the top surface of the stack, the amount
of force transmitted to a particular point either internal to the
stack or on the surfaces of the stack.
[0029] Consider a particular stack on which is imposed a
rectangular coordinate system (x,y,z). Further, suppose that the
vector function F(x,y,z) represents the magnitude of the force
experienced at point (x,y,z) of the stack from a known exogenous
impact on the stack. Yet further, suppose that experimental data
results in measurement of the value of F(x,y,z) at N particular
stack points, say
(x.sub.i,y.sub.i,z.sub.i)(i=1, . . . ,N)
[0030] Based on the geometric description of the stack, the
properties of the materials composing the stack, and an analysis of
the physics of force transmission through the stack, the general
mathematical form of the function F(x,y,z), up to a set of
parameters. For example, in a simple case, the function might have
the form:
F(x,y,z)=ax+by+cz
a linear function, involving three parameters a,b,c, which must be
determined. Generally, the experimental data results in an
over-determination of a,b,c, so that no set of values for a,b,c
exactly matches the experimental data. The best that can be done is
to determine the values of a,b,c is some "optimal fashion"--that
is, so that some error function is minimized. The most common such
error function is the sum of squares function:
E ( a , b , c ) = i = 1 N ( F ( x i , y i , z i ) - ax i - by i -
cz i ) 2 ##EQU00001##
[0031] In case F(x,y,z) is linear, as in the above example, the
determination of a,b,c is just the well-known problem of linear
regression analysis. However, in actual practice, the function F
may involve more or fewer parameters and is generally highly
non-linear, especially for materials with complicated behaviors. In
such instances, the error function E is a much more complex
function and the problem of minimizing the sums of the squares of
the errors is a non-linear optimization problem, which we have had
considerable experience addressing.
[0032] In order to proceed from the local models to actual helmets
configurations, an accepted technique from finite-element analysis
can be used, namely subdividing a helmet configuration into a large
number of elemental configurations, the analysis of each of which
can be handled by a local model, and then analyzing the interaction
among adjacent elemental configurations.
[0033] For the case of the helmet configurations, the surface of
the helmet can be divided into a triangular lattice. Corresponding
to each triangle, a triangular prism can be obtained by a radial
cut into the helmet along each side of the triangle. Each
triangular prism can be regarded as embedded within a circular
stack and thus subject to the analysis of a local model, which
would allow an assessment of the transmission of forces between
adjacent prisms in response to an exogenous force anywhere on the
helmet surface.
[0034] Of particular interest would be the proportion of the
initial energy which is transmitted to the bottom of the prisms,
the maximum forces transmitted, and their respective locations.
This information can be used to compare the effectiveness of
various material stacks and helmet configurations.
[0035] Having disclosed some mathematical modeling used to optimize
helmet layer design, the disclosure now turns to FIG. 1 and FIG. 2.
FIG. 1 and FIG. 2 illustrate an improved safety helmet design that
reduces both the kinetic energy induced by impact and rotational
forces by utilizing foam expansion structures having graded
properties. The safety helmet will better protect the brain by
limiting both direct missile trauma and secondary kinetic effects.
The safety helmet 102 receives contact of an object that transfers
kinetic energy to a first composite layer 104, 202; the composite
having a polymer matrix 106 and a ceramic reinforcement (a fiber)
108. Alternately, the first composite layer 104 is a composite
having a polymer matrix 106 and glass reinforcement 108. A polymer
is a large molecule composed of repeating structural units, the
units typically connected by covalent chemical bonds. Polymers are
both natural and synthetic materials with varying properties.
Natural polymeric materials include shellac, and cellulose and
synthetic polymers include neoprene, PVC, silicon and more.
[0036] The safety helmet uses a second composite layer 110 adjacent
to the first composite layer 104 designed such that the second
composite layer 110 compresses and expands into an expansion zone
112 in the second composite layer to transfer kinetic energy
laterally with respect to the skull 120, 204. The second composite
layer has a first set of expansion structures 116 and a second set
of expansion structures 118, and at least one expansion structure
114 of the first set of expansion structures and the second set of
expansion structures expands into an expansion zone 112 in the
second composite layer 110. Each expansion structure in the first
set of expansion structures 116 has a base configured adjacent to
the first composite layer 104 and each expansion structure has a
first tip. The second set of expansion structures 118 is configured
such that a respective second tip of each expansion structure in
the second set of expansion structures 118 is in contact with the
first tip of a corresponding expansion structure in the first set
of expansion structures 116 in a mirrored configuration.
[0037] Expansion structures in the second composite layer 110 are
made of material that deforms under impact with an object to
transfer kinetic energy, such as flexible foam or polyurethane or
any other material capable of deforming under impact to transfer
kinetic energy. The second composite layer 110 serves as an inner
shock absorption layer designed to slow or redirect the transfer of
force from an impacting object to the head. This is accomplished by
slowing the transfer in a graded fashion and/or redirecting some of
the load away from the head. The absorption layer 110 can have
multiple foam expansion structures with graded physical properties.
The graded physical properties can be created from the chemical
composition of the foam, by incorporation of different sizes of
reinforcements, or by physical shaping of the foam. The foam can be
composed of any suitable compressible material formulated to have a
range of mechanical compression strength. The expansion structures
can have varying sizes and shapes, and can be made of the same or
differing materials.
[0038] FIG. 3 illustrates a side view of safety helmet layers
utilizing foam expansion structures having varying sizes. The first
set of expansion structures 304 in the second composite layer 308
has bases adjacent to the first composite layer 302 and the second
set of expansion structures 306 in the second composite layer 308
has tips in contact with respective tips of corresponding expansion
structures in the first set of expansion structures 302 in a
mirrored configuration. The expansion structures can be foam
structures made of suitable compressible material having a graded
modulus. A modulus is a quantity that expresses the degree to which
a substance possesses a property. A graded modulus is a substance
containing varying degrees of a physical property. The foam
expansion structures have a low modulus at the tips 310 with the
modulus in each expansion structure increasing as it moves from the
tip 310 to the base 312 such that the modulus is greatest, or the
material is the most dense, at the bases 312 of the expansion
structures. Alternately, the graded modulus contains material at
the tip of the expansion structure having a high modulus and the
modulus in each expansion structure decreasing as it moves from the
tip to the base of each expansion structure, such that the modulus
is the least at the bases of the expansion structures.
Additionally, FIG. 3 illustrates exemplary physical shaping of
expansion structures. A second composite layer 308 can have a first
set of expansion structures having a triangular shape of a first
size 304 and can have a second set of expansion structures having a
triangular shape of a second size 306. Alternately, expansion
structures in the first and the second sets can have the same
size.
[0039] FIG. 4 and FIG. 5 illustrate side views of safety helmet
layers having expansion structures with varying shapes. The second
composite layer 402 can have a first set of expansion structures
404 having a rounded tip 406 and a second set of expansion
structures 408 having a triangular shape of 410. An alternate
second composite layer 502 can have a first set of expansion
structures having a triangular shape 504 and a second set of
expansion structures having a rectangular shape 506 with a
triangular tip. The expansion structures in the composite layers
402, 502 have a low modulus at the tips with the modulus in each
expansion structure increasing as it moves from the tip to the base
such that the modulus is the greatest at the bases of the expansion
structures. Graded physical properties of a foam expansion
structure such as chemical composition of the foam, varying sizes
of an expansion structure and physical shaping of foam that can
transfer kinetic energy laterally with respect to the skull are
considered and should not be limiting in any way.
[0040] At least one expansion structure in a second composite layer
of a helmet 102 compresses such that the expansion structure
expands into expansion zones surrounding the expansion structures.
FIG. 6 illustrates a side view of a safety helmet layer having a
second composite layer 602 with a first set of expansion structures
604 and a second set of expansion structures 606 and expansion
zones 608 surrounding the expansion structures. The expansion zones
are pockets of air surrounding the expansion structures 608 in the
second composite layer. An expansion zone can have of any other
chemical composition such as other types of gas such as oxygen and
should not be limiting. Prior to impact by an object, the sets of
expansion structures 604, 606 are in their natural and uncompressed
states and the expansion zones 608 are empty.
[0041] FIG. 7 illustrates a side view of a safety helmet having
compressed expansion structures. After a safety helmet 102 receives
impact by an object 702 that transfers kinetic energy at a first
composite layer 704, expansion structures 708, 710 in the second
composite layer 706 compresses and material expands into expansion
zones 714. An object that delivers a greater impact causes a
greater deformation of expansion structures and fills expansion
zones more than an object that delivers a lesser impact. The safety
helmet transfers kinetic energy laterally with respect to the skull
into expansion zones to absorb impact from the object 702 instead
of directly to the skull.
[0042] FIG. 8 illustrates a side view of a safety helmet having
partially compressed expansion structures. In one embodiment,
expansion structures compress at varying degrees. After a safety
helmet 102 receives impact by an object 802 that transfers kinetic
energy at a first composite layer 804, expansion structures 810 in
the second composite layer 806 compresses and material expands into
expansion zones 812. Expansion structures 810 in the second
composite layer 806 closest to the impacting object 802 can receive
the greatest amount of force by the object and can compress the
greatest compared to expansion structures 814 further from the
impacting object 802.
[0043] A safety helmet utilizing foam having graded properties can
have a first composite layer 104 that comes in direct contact with
an object, such as shrapnel from an exploded road-side bomb. The
first composite layer 104 can have a ceramic reinforcement 106 and
a polymer matrix 108. The second composite layer 110 can have a
first set of expansion structures 116 having a triangular shape of
a first size and can have a second set of expansion structures 118
having a triangular shape of a second size, wherein the first and
second sizes are equal. The structures compress and expand into an
expansion zone 112 after impact with the shrapnel. The shock
absorbing second composite layer 110 redirects the transfer of
force from the impacting object, in this case shrapnel, to the head
by transferring the force to the foam expansion structures, moving
the force laterally with respect to the skull instead of inward
toward the head.
[0044] In one embodiment, a safety helmet utilizing foam structures
having graded properties can have any number of composite layers
wherein each composite layer contains a first set of expansion
structures and a second set of expansion structures and at least
one expansion structure compresses and expands into an expansion
zone upon impact with an object that transfers kinetic energy. Each
composite layer can be adjacent to the immediately preceding layer.
For example, a safety helmet can have three layers, wherein the
first composite layer can have a ceramic reinforcement and polymer
matrix and serve as first contact with an object. A second
composite layer adjacent to the first composite layer can have a
first set of expansion structures having a triangular shape of a
first size and can have a second set of expansion structures having
a triangular shape of a second size. A third composite layer
adjacent to the second composite layer can have a first set of
expansion structures having a triangular shape of a third size and
can have a second set of expansion structures having a rectangular
shape with a triangular-shaped tip. Upon impact with an object that
transfers kinetic energy, expansion structures in the second and
third composite layers compress and expand into surrounding
expansion zones. In this way, force delivered by an object is
transferred to foam expansion structures in the second and third
composite layers by moving the force laterally instead of directly
to the head. Any number of composite layers having expansion
structures is contemplated such as five, seven or nine.
[0045] The various embodiments described above are provided by way
of illustration only and should not be construed to limit the scope
of the disclosure. Thus, for a claim that recites a structure that
deflects and spreads kinetic energy, the structure could apply in
any application disclosed herein (vehicle, helmet, body armor,
building protection, etc.) as well as other structures not listed.
Those skilled in the art will readily recognize various
modifications and changes that may be made to the principles
described herein without following the example embodiments and
applications illustrated and described herein, and without
departing from the spirit and scope of the disclosure.
* * * * *