Football helmet having improved impact absorption

Abstract

A football helmet is disclosed that includes a shell constructed of fiber reinforced epoxy resin, a liner made from expanded polypropylene, an impact absorbing layer situated between the liner and the shell, and a face gaurd. The impact absorbing layer is constructed from either expanded polypropylene or a viscoelastic polymer encased in a suitable thin yet resilient and elastic membrane. An optional impact absorbing band is also shown disposed around the inner periphery of the liner and encircling the player's head. The impact absorbing band serves to reduce impact forces occurring from side helmet impact with objects or players. An alternate helmet liner is also disclosed having hexagonal apertures situated in the crown thereof to lower the density of the EPP material in that region and improve energy absorbing characteristics of the helmet assembly.

Description

FIELD OF THE INVENTION

This invention relates in general to protective head gear and more specifically to football helmets.

BACKGROUND OF THE INVENTION

Helmets have long been worn in the sport of football to protect a player's head from injury resulting from impact with other players, ground impact, or impact with objects on or off the field. Recent prior art helmets typically include an outer shell made from durable plastic materials, a liner made from a shock absorbing material, a face guard and a chin strap which also functions in some designs as a chin protector. Helmet liners have taken several forms over the years, including encased foam padding, fluid filled jackets or pockets, air inflated bags lining the inner surface of the helmet and other design approaches.

Some recent patents directed to football helmets, such as U.S. Pat. Nos. 7,240,376, 6,934,971 and 7,036,151, all to Ide et al., have focused more on jaw protection, ear protection and improved face guard features without any notable changes in the shock absorbing liner designs. In general though, the overall configuration, design and shape of a football helmet has remained relatively unchanged over an extended period of time.

It is well recognized that no helmet can completely prevent injuries to persons playing the sport of football. The very nature of football is quite physical with much emphasis placed on strength and speed of the players. As players have increased their strength and speed, corresponding improvements in safety equipment, specifically helmets, has not taken place. Shock attenutation and impact force absorption are of foremost importance in the design of a football helmet.

Serious concerns have been raised in recent years regarding concussion injuries suffered by athletes while playing football and the long term affect such brain injuries have on the mental and physical health of those suffering such injuries. Some commentators suggest there may be significant consequences for continuing to play football before recovery from a concussion injury has taken place. Later life cognitive difficulties suffered by former football players are now being associated with concussion injuries received while playing football. Recently, researchers found the players were three times more likely to die from Alzheimer's, Parkinson's or Lou Gehrig's disease than the general population.

Given the recent media coverage of high profile football players who received concussion injuries while playing football and have later in life suffered from maladies and diseases of the brain resulting in abnormal life experiences and behavior, it is abundantly clear that more attention and effort should be directed to protecting players from such injuries.

In view of elevated attention concussion injuries are receiving in the media in relation to football, and in particular the long term negative impact on lives, any new developments in football helmet designs that improve the impact absorption or impact attenuation characteristics of a football helmet and lessen the forces impacting the head of a player are urgently needed.

SUMMARY OF THE INVENTION

A football helmet according to one aspect of the present invention includes a shell having an inner surface, an outer surface, an opening over the face area of the wearer, a crown area and wherein the shell is constructed of fiber reinforced epoxy resin and adapted to receive an athlete's head therein, an energy absorbing layer situated adjacent the inner surface of the shell and extending over the crown area of the shell, a liner having an outer surface conforming with the inner surface of the shell and the energy absorbing layer adjacent the inner surface of the shell and an inner surface closely conforming to the head of the wearer, the liner disposed within the shell such that the energy absorbing layer is situated between the liner and the shell in the crown area of the shell, the liner having a substantially uniform thickness and fabricated from expanded polypropylene, a face mask attached to the shell over the face area of the shell, and wherein the energy absorbing layer has a higher compressive strength than the compressive strength of the liner.

One object of the present invention is to provide an improved football helmet.

Another object of the present invention is to provide a football helmet that is lighter than prior art helmets.

Still another object of the present invention is to provide a football helmet that includes improved impact attenuation and shock absorbing features.

Yet another object of the present invention is to significantly reduce impact forces that are transmitted through a football helmet to the head of the player wearing the helmet.

These and other objects of the present invention will become more apparent from the following description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevational view of a football helmet according to one aspect of the present invention.

FIG. 2 is a bottom view of the football helmet of FIG. 1.

FIG. 3 is an exploded perspective view of the helmet of FIG. 1.

FIG. 4 is an exploded side view of the helmet of FIG. 1.

FIG. 5 is a plan view of the energy absorbing layer shown.

FIG. 6 is a plan view of an alternative energy absorbing layer.

FIG. 7 is a side view of the helmet shell depicting areas wherein additional reinforcing material are applied.

FIG. 8 is a plan view of the helmet shell depicting areas wherein additional reinforcing material are applied.

FIG. 9 is a plan view of the reinforcing material used to construct the helmet shell with an enlarged view of the fiber makeup.

FIG. 10 is an exploded perspective view of another embodiment of a football helmet according to the present invention.

FIG. 11 is a bottom view of another embodiment of a football helmet according to the present invention.

FIG. 12 is a perspective view of the energy absorbing band shown in FIG. 11.

FIG. 13 is an exploded perspective view of another embodiment of a football helmet shell and liner assembly according to the present invention.

FIG. 14 is a plan view of the helmet liner shown in FIG. 13.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated devices, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

Referring now to FIGS. 1 and 2, a football helmet 10 according to one aspect of the present invention is shown. FIG. 1 is a front elevational view and FIG. 2 is a bottom view of helmet 10. Helmet 10 includes a shell 12, a face guard or face mask 14, an energy absorbing liner 16, jaw pads 18, and face guard connectors 20. Face guard connectors 20 and screws 24 secure face guard 14 to shell 12. Face guard connectors 20 are secured to shell 12 by screws 24 and nuts (not shown) situated on the inner surface of shell 12. Jaw pads 18 are attached to shell 12 using snap connectors or hook and loop fasteners (not shown). Chin strap snaps 26 are attached to shell 12 by threaded nuts (not shown) situated on the inner surface of shell 12 that engage a threaded portion of snaps 26 which extends through shell 12. Ear apertures 28 in shell 12 are situated over the player's ears and allow sound waves s to readily pass therethrough. Fasteners for attaching face guards, jaw pads and chin straps to football helmets are well known in the art.

Shell 12 is relatively thin (typically less than one-eighth inch or less than 3 mm thick) and constructed of fiber reinforced epoxy resin formed in a shape that is generally conforming with yet larger than a human head. Shell 12 includes a face opening 13 and a head opening 15. Shell 12 is thinner than prior art helmets and weighs substantially less than prior art shells made from polycarbonates or other known plastic materials. Liner 16 is fabricated from expanded polypropylene (EPP) and has an inner surface 16a that closely conforms with the general external shape of a human head. The inner surface of liner 16 is covered with a moisture wicking or moisture absorbing cloth material 17 to absorb perspiration from the player's head. The outer surface of liner 16 is shown in more detail in FIG. 3 wherein an energy absorbing layer is also shown in more detail situated between shell 12 and liner 16. Fitment pads 22 are attached to liner 16 about the inner periphery of liner 16 at multiple locations to achieve a comfortably snug fit of helmet 10 on a football player's head. Fitment pads 22 are made from fabric encased resilient foam padding material and are attached using adhesives, hook and loop fasteners or the like or other attachment means well known in the art. Fitment pads 22 are available in various thicknesses to accommodate varying head sizes within liner 16. In order to accommodate a large range of head sizes, liner 16 may also be fabricated in a variety of thicknesses and in combination with various sized fitment pads all sizes of human heads are accommodated within helmet 10.

Liner 16 is preferably constructed with external dimensions along the head opening 13 and face opening 15 of shell 12 that are slightly larger than the inner dimensions of shell 12 to create a slight interference fit within shell 12. The process for inserting liner 16 within shell 12 includes slightly compressing liner 16 toward the middle at the edges thereof for installation into shell 12. Liner 16 is retained within shell 12 as a result of the subsequent resilient expansion of liner 16 against the inner surfaces of shell 12. Alternatively, liner 16 may be constructed with external dimensions in the face and head openings to be an exact fit to the inner surfaces of shell 12 and liner 16 is then attached to the inner surfaces of shell 12 using contact adhesive or the like.

Liner 16 is fabricated from expanded polypropylene since it is a highly versatile closed-cell bead foam or foam form of polypropylene that provides a unique range of properties, including outstanding energy absorption, multiple impact resistance, thermal insulation, buoyancy, water and chemical resistance, exceptionally high strength to weight ratio and 100% recyclability. EPP has very good impact characteristics due to its low stiffness; this allows EPP to resume its shape after impacts. EPP foam possesses superior cushioning properties, is able to absorb kinetic impacts very well without breaking, retains its original shape, and exhibits memory form characteristics which allow it to return to its original shape in a short amount of time. Polypropylene, in general, is not only resilient but also resistant to most solvents and glues.

Referring now to FIGS. 3 and 4, a perspective and side elevational exploded view of helmet 10 are shown, respectively, depicting shell 12, liner 16 and energy absorbing layer 30. During assembly of shell 12 and liner 16, energy absorbing layer 30 is situated in recessed area 16b of liner 16. The dimensions of recessed area 16b are such that layer 30 is in contact with the recessed external surface area 16b and the inner surface of shell 12. Liner 16 is shown in FIGS. 3 and 4 with moisture wicking material 17 removed. Shell 12 is shown with jaw pads 18 removed to more clearly illustrate the assembly process of inserting liner 16 and layer 30 within shell 12. Layer 30 is a resilient membrane with a plurality of energy absorbing nodules suspended therein. The energy absorbing material in layer 30 has a compressive strength greater than the compressive strength or impact attenuation property of the expanded polypropylene of liner 16. Peripheral surface 16c of liner 16 is compressed slightly to enable insertion of liner 16 within shell 12. Face guard 14 and ear apertures 28 are also shown in FIGS. 3 and 4.

FIGS. 5 and 6 illustrate two different variations for energy absorbing layer 30 presently available, though other geometric arrangements are also contemplated. Energy absorbing layer 30 consists of a flexible resilient membrane 30a that encases an array of viscoelastic polymer material 30b into pockets within membrane 30a. Layer 30 is produced by Impact Innovative Products of 127 Industry Blvd., Irwin, Pa. 15642 and referred to as Zoombang® impact attenuation material by the Impact Innovative Products. FIG. 5 depicts one version of energy absorbing layer 30 having an array of hexagonal pockets of the viscoelastic polymer. FIG. 6 depicts an alternate configuration for energy absorbing layer 31 which includes an array of elongated rounded rectangular pockets 31b of the viscoelastic polymer suspended in resilient flexible membrane 31a. The precise formulation of the Zoombang® material is presumably a trade secret of Impact Innovative Products. The general geometric configuration of resilient flexible layers 30 and 31 shown in FIGS. 5 and 6, respectively, are intended to be formed to and placed over the pseudo-spherical surface defined by the external surface of recessed portion 16b of liner 16 (see FIGS. 3 and 4) such that the entirety of surface 16b is well covered and contacted by one side of layer 30 or layer 31. It is also contemplated that a very thin layer of contact adhesive may be used to maintain layer 30 or 31 in position over recessed surface 16b when liner 16 and layer 30 are assembled into shell 12.

Referring now to FIGS. 7 and 8, a side elevational view and a plan view of shell 12 are shown, respectively, with a number of areas defined by broken lines that depict locations wherein the amount of reinforcing material applied during fabrication of shell 12 will vary. In general, shell 12 includes four (4) layers of reinforcing mesh in area 12a, three (3) layers of reinforcing mesh in area 12b, and six (6) layers of reinforcing mesh in areas marked 12c. The variation in reinforcing material layer count is directly related to the desired strength and amount of resiliency or stiffness desired for the noted regions. In area 12b over the brain it is desired that shell 12 have more “reslience” or “flex” upon heavy impact. Area 12a may be slightly stiffer in resilience, thus four layers are applied therein. Significant strength is desired in area 12c where face guards, jaw pads and chin straps are attached, thus six layers of reinforcing material are applied therein during fabrication of shell 12.

Referring now to FIG. 9, a detailed view of the reinforcing mesh 32 encased in epoxy resin to fabricate shell 12 is shown. Mesh 32 includes preferably three different fiber types, namely, carbon fibers, fiberglass fibers and Kevlar® fibers. One combination of fibers that provides desirable strength characteristics along with resiliency and toughness includes a 40 (forty) percent carbon fiber, 40 (forty) percent Kevlar fiber and 20 (twenty) percent fiberglass fiber ratio woven into a mesh as shown in FIG. 9. Kevlar® fiber bundles 34, carbon fiber bundles 36 and fiberglass fiber bundles 38 are cross woven as shown to fabricate mesh 32. The Kevlar® fiber bundles 34 and carbon fiber bundles 36 in mesh 32 are larger in individual fiber count than the fiberglass fiber bundles 38 such that the approximate fiber makeup of 40% Kevlar® fiber, 40% carbon fiber and 20% fiberglass fiber content is achieved.

Referring now to FIG. 10, another embodiment of a football helmet 50 according to the present invention is shown in a perspective exploded view. All aspects and components of helmet 50 are identical to those shown for helmet 10 with the exception of cap 52 which replaces energy absorbing layer 30. Helmet 50 of FIG. 10 is shown without jaw pads for convenience in illustrating the exploded view, but it is contemplated that jaw pads are included with helmet 50. In addition, liner 54 is shown with moisture wicking cloth removed. Cap 52 occupies and completely fills the space between liner 54 and shell 56 when helmet 50 is assembled. The lower surface of cap 52 is formed to coincide precisely with the upper pseudo-spherical recessed surface 54b of liner 54 and the external upper surface of cap 52 conforms with the inner surface of shell 56. Thus, cap 52 completely fills the void defined between shell 56 and liner 54. Cap 52 is fabricated from EPP with a higher density than that of the EPP used to fabricate liner 54. Thus, cap 50 has a higher energy absorbing capability or increased impact attenuation as a result of the higher density of the EPP therein. The density of the EPP used to fabricate liner 54 is typically between 2 and 4 pounds per cubic foot and the density for the EPP used in fabricating cap 52 is typically between 4 and 6 pounds per cubic foot, though it is contemplated that other combinations of densities may be desirable to achieve specific impact attenuation results for the combination of liner 54 and cap 52. For example, where players are young and smaller with less speed and strength abilities, lower densities of EPP for the liner and cap may be more appropriate.

Referring now to FIGS. 11 and 12, another embodiment of a football helmet having an additional impact attenuation feature according to the present invention is shown that is used in conjunction with either helmet 10 or helmet 50. FIG. 11 is a bottom view of either helmet 10 or helmet 50 depicting energy absorbing band 60 installed about the inner periphery of the helmet liner so that the player's head is encircled by band 60. FIG. 12 is a perspective view of energy absorbing band 60. Band 60 is flexible and resilient as it is fabricated from energy absorbing material encased in a thin resilient flexible membrane. Band 60 is situated within the helmet and attached about the inner periphery of the helmet to provide side force impact attenuation for the player's head. Band 60 is disposed over fitment pads 22 and attached to pads 22 and helmet liner 16 or 54. Energy absorbing band 60 is approximately 1 to 2 inches in height and has a higher compressive strength than liners 16 or 54. Band 60 is fabricated from a viscoelastic polymer material such as Zoombang® material, previously discussed, and preferably encased in a moisture absorbing or moisture wicking cloth. Band 60 is attached to liners 16 or 54 and over fitment pads 22 by either adhesives or hook and loop fasteners (not shown), as is well known in the art.

Many different materials are known that have energy absorbing characteristics coupled with resiliency as exhibited by EPP and the substitution of such materials in the present invention is contemplated. Energy absorbing materials such as viscoelastic polymers having compressive strength or impact attenuation properties similar to the Zoombang® material are contemplated as substitutes therefore in the present invention.

Referring now to FIG. 13, an exploded perspective view of another embodiment of a helmet shell and impact absorbing liner assembly for a football helmet according to the present invention is shown. All component parts for helmet 70 are identical in function and form to those shown for helmet 10 with the exception of cap 80 and liner 82. Cap 80 and liner 82 replace the energy absorbing layer 30 and liner 16, respectively, of helmet 10. Helmet 70 includes a face guard 72 attached to shell 74 using fasteners 76 well known in the football helmet art. Shell 74 is identical to shell 12 in construction and configuration and is shown for reference purposes. Snaps 78 provide a mechanism for attaching a chin strap (not shown) to helmet 70. Cap 80 is situated within and adjacent the inner surface of shell 74 with external upper surface 80a of cap 80 conforming to the inner and upper surface of shell 74. Cap 80 is identical to cap 52 of FIG. 10. Cap 80 includes a concave lower surface 80b. Liner 82 includes a shallow recessed region 84 that receives and mates with the concave lower surface 80b of cap 80. Cap 80 is situated atop liner 82 to form an assembly that mates with and conforms to the inner surface of shell 74. Liner 82 and cap 80 are fabricated using EPP or expanded polypropylene. Cap 80 is fabricated or molded using a higher density EPP formulation and liner 82 is fabricated or molded using a lower density EPP material. For example, liner 82 is made from EPP having a density of two to four pounds per cubic foot and cap 80 is made from EPP having a density higher than four pounds per cubic foot, though EPP densities outside these ranges are contemplated with the primary requirement being the differing EPP formulation densities for the cap 80 and liner 82.

Practical limitations are well known in the art of forming or molding EPP into a solid structure, that is, voids and material durability problems may arise when the density and dimensions of an EPP based solid is reduced below well known limits for low density EPP formulations such as, for example, one-half pound per cubic foot. Since a football helmet will receive a large number of physical impacts over time, it is essential to ensure long term durability for the energy absorbing component parts used in construction thereof.

In order to reduce the density of the EPP material of liner 82 in the region of contact with cap 80, a plurality of apertures 86 are formed in the upper surface of liner 82. Hexagonal apertures 86 are radially formed in the external surface of recessed region 84 either by machining or molding processes well known in the art. Hexagonal apertures 86 reduce the density of the EPP material in the vicinity of apertures 86 to a density level lower than that which is achievable using traditional molding processes for solid EPP. The effect of apertures 86 is to create a much lower density region or layer that enables physical deflection or compression of liner 82 at a lower impact force in the area of apertures 86. The result is acceleration and deceleration of the head of the wearer of helmet 70 are reduced following an impact, thereby lessening the forces that urge the brain in contact with the interior of the skull for the user of helmet 70. A lowering of the acceleration and deceleration forces transmitted to the users head will provide improved protection against undesirable head injury as a result of sudden impact forces to the external surfaces of shell 74.

Referring now to FIG. 14, a plan view of liner 82 is shown. The array of hexagonal apertures 86 is shown in more detail in FIG. 14 extending over the entire upper surface or crown area of liner 82. The wall thickness 88 between apertures 86 is contemplated to be in the range of one-eighth inch to one-half inch, though wall thickness dimensions outside this range are contemplated so long as the EPP material is not likely to suffer any permanent physical damage during use. If a higher level of energy absorption is desired, wall thickness 88 may be increased or the distance between parallel sides of (or the area of) the hexagonal apertures 86 may be decreased, or a combination of the two dimensions may be used to increase energy absorption levels in the area of the apertures. It should also be readily recognized that apertures 86 may take the shape of any geometric polygon, including but not limited to triangles, squares, octagons etc., though a polygon with an even number of sides would provide consistent control over wall thickness and wall separation distances versus polygons with an odd number of sides. Mold complexity may also impact the decision making process in determining the desired shape for apertures 86, as well as machining processes should apertures 86 be formed using a material removal machining process.

It is also contemplated that apertures 86 in liner 82 may vary in dimension in a stepped or continuous fashion to a much smaller hexagonal size at their most extreme depth in liner 82 thereby creating a varying energy absorption response in accordance with the deformation depth of the EPP material in the region of the apertures during an impact event. Wall thickness between the apertures could readily increase at any desired rate (linear or non-linear) from the surface of region 84 to the full depth of the aperture to achieve a desired energy absorption rate or curve. Semi-spherical apertures would also provide a similar benefit creating a wall thickness that increases with the depth of the aperture and thereby providing a varying impact absorbing capability dependent on deformation depth, wherein the larger the impact force, the larger the cross-sectional area of EPP material that would experience compression and resist the force applied.

It should be noted that the embodiment for helmet 70 includes all the features of helmet 10, and that FIG. 13 is directed specifically to the alternative internal components that differ from helmet 10, namely liner 82 and cap 80.

While the invention has been illustrated and described in detail in the drawings and foregoing description of the preferred embodiments, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.

Claims

1. A football helmet comprising: a shell having an inner surface facing a wearer, an outer surface facing away from the wearer when the helmet is worn, an opening adapted to be over a face area of the wearer, a crown area and wherein said shell is constructed of epoxy resin including fiber reinforcing material and adapted to receive an athlete's head therein, and wherein said fiber reinforcing material in the crown area is lower than the fiber reinforcing material in areas outside the crown area of said shell;an energy absorbing layer situated adjacent the inner surface of said shell and extending over the crown area of said shell;a liner having an outer surface conforming with the inner surface of said shell and said energy absorbing layer adjacent the inner surface of said shell and an inner surface closely conforming to the head of the wearer, said liner disposed within said shell such that said energy absorbing layer is situated between said liner and said shell in the crown area of said shell, said liner having a substantially uniform thickness and fabricated from expanded polypropylene, said liner including a plurality of uniformly spaced apart polygonal apertures formed in said liner in the area adjacent said energy absorbing layer, and wherein said polygonal apertures extend partially into said liner a predetermined distance that is less than the substantially uniform thickness of said liner;a plurality of fitment pads situated about and attached to the inner surface of said liner for sizing said liner to the head of the wearer;a face mask attached to said shell over the face area of said shell; andwherein said energy absorbing layer has a higher compressive strength than the compressive strength of said liner.

2. The device of claim 1 wherein said energy absorbing layer is expanded polypropylene having a density higher than the density of said liner.

3. The device of claim 2 wherein the fiber reinforcing material of said shell is a fiber mesh including carbon fibers, Kevlar fibers and fiberglass fibers.

4. A football helmet comprising: a shell having an inner surface facing a user, an outer surface facing away from the user when the helmet is worn, an opening over the face area of the user, a crown area and wherein said shell is constructed of epoxy resin including fiber reinforcing material and adapted to receive an athlete's head therein, and wherein said fiber reinforcing material in the crown area is lower than the fiber reinforcing material in areas outside the crown area of said shell;means for absorbing energy disposed along the inner surface of said shell and extending over the crown area of said shell;a liner having an outer surface conforming with the inner surface of said shell and said means for absorbing energy situated adjacent the inner surface of said shell, said liner having an inner surface closely conforming to the head of the wearer, said liner having a substantially uniform thickness in the area adjacent said crown area of said shell, said liner disposed within said shell such that said means for absorbing energy is situated between said liner and said shell in the crown area of said shell, said liner including a plurality of radially oriented polygonal apertures extending partially into said liner a predetermined distance that is less than the uniform thickness of said liner in the area adjacent said crown area of said shell, said plurality of apertures being uniformly spaced apart and situated adjacent said means for absorbing energy and wherein said liner is fabricated from expanded polypropylene;a plurality of fitment pads situated about and attached to the inner surface of said liner for sizing said liner to the head of the wearer;a face mask attached to said shell over the face area of said shell; andwherein said means for absorbing energy has a higher compressive strength than that of said liner.

5. The device of claim 4 wherein said means for absorbing energy is a thin layer of expanded polypropylene having a density higher than the density of said liner.

6. The device of claim 5 wherein the fiber reinforcing material of said shell is a fiber mesh including carbon fibers, Kevlar fibers and fiberglass fibers.

7. A football helmet comprising: a shell having an inner surface facing a wearer, an outer surface facing away from the wearer, an opening adapted to be over a face area of the wearer, a crown area corresponding to the upper portion of said shell, and wherein said shell is constructed of epoxy resin including fiber mesh reinforcing material and adapted to receive an athlete's head therein, and wherein said fiber reinforcing material in the crown area is lower than the fiber reinforcing material in areas outside the crown area of said shell;an energy absorbing layer situated adjacent the inner surface of said shell and extending over the crown area of said shell, said energy absorbing layer being fabricated from expanded polypropylene, and wherein said energy absorbing layer has a substantially uniform thickness;a liner having an outer surface conforming with the inner surface of said shell and said energy absorbing layer situated adjacent the inner surface of said shell, said liner also having an inner surface closely conforming to the head of the wearer, said liner having a liner thickness substantially larger than the substantially uniform thickness of said energy absorbing layer, said liner disposed within said shell such that said energy absorbing layer is situated between said liner and said shell in the crown area of said shell, said liner being fabricated from expanded polypropylene, said liner including a plurality of spaced apart polygonal apertures formed in said liner in the area adjacent said energy absorbing layer, said plurality of apertures extending partially into said liner a predetermined distance that is less than the liner thickness;a plurality of fitment pads situated about and attached to the inner surface of said liner for sizing said liner to the head of the wearer;a face mask attached to said shell over the face area opening of said shell; andwherein said energy absorbing layer is formed from expanded polypropylene having a higher compressive strength formulation than the expanded polypropylene formulation used for said liner.

8. The device of claim 7 wherein the fiber mesh reinforcing material of said shell is a fiber mesh including a combination of carbon fibers, Kevlar fibers and fiberglass fibers.

9. The device of claim 8 wherein said plurality of polygonal apertures are hexagonal in cross-section and arranged so that the distance between centers of adjacent apertures is fixed throughout the plurality of polygonal apertures.

10. The device of claim 9 wherein the wall thickness of said liner between adjacent hexagonal apertures is greater than one-eighth inch.