US20150164173A1

US20150164173A1 - Helmet with external scales

Info

Publication number: US20150164173A1
Application number: US14/107,319
Authority: US
Inventors: J. Stephen West
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-12-16
Filing date: 2013-12-16
Publication date: 2015-06-18

Abstract

A protective covering for a helmet. The protective covering includes a cushioning layer with a plurality of overlapping scales disposed on an exterior surface thereof. The covering overlies an outer surface of a substantially rigid shell of a helmet and provides additional padding via the cushioning layer to absorb impact forces received by the helmet. The scales are deflectable relative to one another to compress the cushioning layer when an impact force is received and are configured to reduce the coefficient of friction between the covering and an impacting body to thereby increase deflection of the impacting force and the impacting body. The protective covering can be applied to existing helmets or can be integrated into helmets during manufacture thereof.

Description

BACKGROUND

For centuries, people engaged in sporting events, combat, and other physical endeavors have used helmets and other protective head coverings to protect against head injuries. Such injuries might result from contact with sharp or blunt objects, weapons, projectiles, or the heads or bodies of other participants or combatants. The potential injuries range from external cuts and bruises to internal injuries to the brain as found in concussion-related injuries.
Concussions and related head injuries and their effects on the injured person, especially those associated with players of American football and related sports, have received close scrutiny in recent times. Many attempts have been made to produce improved helmets that absorb and/or disperse forces associated with collisions between a player's helmet with other players' helmets and bodies and with the ground or other obstacles. Generally these “improved” helmets are configured to slow the rate of deceleration of the player's head during a collision by absorbing and/or deflecting at least a portion of the energy associated with the collision and/or by deflecting the colliding bodies away from direct, head-on contact. For example, Michael Princip of Silver Spring, Md. has developed the BULWARK helmet which begins with a standard helmet and adds a layer of shock absorbing material over the standard helmet's hard shell. The shock absorbing material is covered by an outer shell formed of four abutting sections. The sections of the outer shell are designed to flex on impact in order to partially absorb collision impacts.
Similarly, U.S. Pat. No. 7,254,843 to Talluri describes a helmet having a rigid shell covered by a honeycomb layer, which is in turn covered by a hard outer layer with minimal sliding friction.
And U.S. Pat. No. 5,956,777 to Popovich, teaches a helmet wherein the hard shell of the helmet is covered first by a resilient spacing layer. The resilient spacing layer is covered by an articulated shell layer formed of rigid segments connected by resilient members, such as elastic bands. The articulated shell layer is covered by a resilient outer shell covering.
There remains a need for a helmet that sufficiently absorbs and deflects impact forces and deflects the impacting bodies to protect the wearer thereof from concussions and other head injuries. There also remains a need for a product that can be applied to existing helmets to provide additional impact protection.

SUMMARY

Embodiments of the invention are defined by the claims below, not this summary. A high-level overview of various aspects of the invention are provided here for that reason, to provide an overview of the disclosure, and to introduce a selection of concepts that are further described in the Detailed-Description section below. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. In brief, this disclosure describes, among other things, a protective covering for helmets and a helmet with integral protective covering.
The protective covering includes a cushioning layer that is covered by a layer of overlapping scales. The cushioning layer may comprise or be encapsulated in a jacket to which the scales are attached. As such, the covering can be applied to an existing helmet in a manner similar to that of a swimmer donning a swim cap and can be fastened to the helmet to retain the covering in place. Helmets can also be constructed with the covering integrated therein.
The cushioning layer of the covering comprises one or more resilient foam-like or similar padding materials. The cushioning is configured to absorb at least a portion of the impact forces encountered by the wearer of the helmet. The cushioning can be of uniform thickness throughout the covering or might be sculpted to provide additional thickness and protection in desired areas.
The scales applied to the exterior of the covering may be configured similarly to scales found in nature in, for example, fish or reptiles. The form and overlapping nature of the scales aid to disperse and deflect the impact forces into the cushioning layer by moving or pivoting relative to one another. The scales also aid deflection of contact between the covering and the impacting object. The scales are constructed from a rigid or resilient material having a low coefficient of friction, which more readily enables sliding of the impacting object along the covering. The form of each of the scales may also be configured to increase the energy absorption thereof and to aid sliding of the impacting object relative to the covering.

DESCRIPTION OF THE DRAWINGS

Illustrative embodiments of the invention are described in detail below with reference to the attached drawing figures, and wherein:

FIG. 1 is a perspective view of an American football helmet fitted with a protective covering depicted in accordance with an embodiment of the invention;

FIG. 2 is a perspective view of a protective covering for a helmet depicted in accordance with an embodiment of the invention;

FIG. 3 is a cross-sectional view of a helmet with a protective covering depicted in accordance with an embodiment of the invention;

FIG. 4 is a graphical illustration showing overlapping scales on a protective covering for a helmet depicted in accordance with an embodiment of the invention;

FIG. 5 is a cross-sectional view showing an impact between two helmets with protective coverings depicted in accordance with an embodiment of the invention;

FIG. 6 is a perspective view of a scale of a protective covering for a helmet depicted in accordance with an embodiment of the invention;

FIG. 7 is a top plan view of the scale of FIG. 6;

FIG. 8 is a side elevational view of the scale of FIG. 6 showing the scale coupled to a jacket on a surface of a protective covering in accordance with an embodiment of the invention;

FIG. 9 is an end elevational view of the scale of FIG. 6 showing the scale coupled to a cushioning layer of a protective covering in accordance with an embodiment of the invention;

FIGS. 10A-E are top plan views of exemplary scale configurations useable with a protective covering for a helmet in accordance with an embodiment of the invention; and

FIG. 11 is cross-sectional side view of a scale coupled to a multi-layered protective covering for a helmet in accordance with an embodiment of the invention.

DETAILED DESCRIPTION

The subject matter of select embodiments of the invention is described with specificity herein to meet statutory requirements, however the description itself is not intended to necessarily limit the scope of claims. Rather, the claimed subject matter might be embodied in other ways to include different components, steps, or combinations thereof similar to the ones described in this document, in conjunction with other present or future technologies. Terms should not be interpreted as implying any particular order among or between various steps herein disclosed unless and except when the order of individual steps is explicitly described.
With reference to the drawings, a protective covering 10 for a helmet 12 is described in accordance with an embodiment of the invention. The protective covering 10 and helmet 12 are shown and described herein with respect to an American football helmet. However, such is not intended to limit embodiments of the invention to any particular helmet style, type, or use or to limit embodiments to helmets alone. Embodiments of the invention might be employed for helmets used in other sports like cycling or hockey or in other endeavors like combat helmets. Embodiments might also be employed in other protective garments, such as shoulder pads, shin guards, elbow- and kneepads, or the like.
The helmet 12 is any available helmet or protective garment. The helmet 12 preferably includes a substantially rigid outer shell 14 and an inner padding layer 16. The helmet 12 may include a facemask 18 or any other desired features, as depicted in FIG. 3. As known in the art, the outer shell 14 is typically formed from a plastic or similar material that has sufficient rigidity to resist deformation upon impact with an object and sufficient resilience to resist breakage. Such materials include, for example, acrylonitrile-butadiene-styrene (ABS) or polycarbonate plastics.
The padding layer 16 is configured to cushion the wearer's head from impacts striking the outer shell 14. The padding layer 16 might be comprised of one or more air bladders or padding layers formed from materials like urethane foams or vinyl nitrile foams, among others. The outer shell 14 and the padding layer 16 can take any desired form and configuration.
The protective covering 10 comprises a cushioning layer 20 with a plurality of overlapping scales 22 disposed to overlie at least a portion of an outer surface thereof. The cushioning layer 20 includes one or more layers of cushioning materials or padding. The cushioning materials can be comprised of one or more foams, rubbers, plastics, fibers, jute, or elastomeric materials, among others, which can be employed alone or in combination. Preferably, the cushioning layer 20 includes a layer of urethane foam.
The cushioning layer 20 can be provided in a single thickness throughout the protective covering 10 or the thickness of the layer 20 might be varied to provide desired protective and/or aesthetic qualities. The thickness of the cushioning layer 20 is preferably less than about 2.0 inches or between about 1.0 and 2.0 inches. The thickness of the cushioning layer 20 might be increased in areas of the helmet 12 having a high propensity or probability for receiving an impact or in which an impact may be more detrimental to the wearer. For instance, as depicted in FIG. 3, a protective covering 10 designed for use by a football quarterback can include a cushioning layer 20 having a greater thickness along the backside of the helmet 12 in an area associated with the back of the head of the wearer to provide additional protection against blindside hits and impacts with the ground. Similarly, a protective covering 10 designed for use by a football running back might have a cushioning layer 20 with greater thickness near the crown of the wearer's head to provide additional protection against head-on collisions that are common for players in that position. Alternatively, the thickness of the cushioning layer 20 can be sculpted or tailored to provide an aesthetic appearance, e.g. the cushioning layer 20 might be sculpted to provide the appearance of a gladiator's or a Viking's helmet.
As best depicted in FIG. 11, multiple layers 24, 26, 28 of cushioning materials can also be employed in the cushioning layer 20. Each of the multiple layers 24, 26, 28 can extend across the entirety of the cushioning layer 20 or one or more of the layers 24, 26, 28 might be present only in select portions of the cushioning layer 20. Such selective placement may enable further tailoring of the amount of padding and protection provided in various regions of the protective covering 10. Further, the cushioning layer 20 and any of the layers 24, 26, 28 that make up the cushioning layer 20 can be selected to provide a desired density and/or durometer to meet the protective requirements of a particular embodiment. The density and durometer of the materials making up the cushioning layer 20 can be uniform or variable across the protective covering 10 and/or the thickness thereof. As shown in FIG. 11, the layers 24, 26, 28 can be comprised of foam materials of increasing density, e.g. a low-density foam layer 24, an intermediate-density foam layer 26, and a high-density foam layer 28. It is also foreseen that the cushioning layer 20 could comprise one or more air bladders either used alone or in combination with other cushioning materials.
The outer surface of the cushioning layer 20 is at least partially covered by the scales 22, which may be affixed to a jacket 30 comprised of one or more fabrics or woven materials such as carbon fiber, polyester, nylon, or the like. Such materials are selectable to provide desired elasticity, resilience, and frictional properties, among other characteristics. The materials comprising the jacket 30 can be selected to provide a low coefficient of friction for any areas of the jacket 30 that are exposed or not covered by the scales 22 or to provide a high coefficient of friction in areas that contact the cushioning layer 20 or outer shell 14 of the helmet 12 to resist relative movement therebetween.
In alternative embodiments, the jacket 30 could also comprise the same material as the cushioning materials; for example, the jacket 30 can be provided by heating the outer surface of the cushioning materials to form a continuous skin thereon. The jacket 30 covers all or part of the outer surface of the cushioning layer 20. The jacket 30 might also be provided on an inner surface of the cushioning layer 20, between the cushioning layer 20 and the shell 14 of the helmet 12, to fully or partially enclose the cushioning materials of the cushioning layer 20. The jacket 30 can be formed in situ, bonded to, or applied over an outermost layer of the cushioning layer 20.
The jacket 30 is preferably at least slightly elastic to enable stretching of the jacket 30 over the helmet 12, but not so elastic that the scales 22 attached thereto will become displaced from their desired positions by deformation of the jacket 30. It is not required that the jacket 30 be significantly elastic as the jacket can be sized to fit tightly over the cushioning layer 20 without stretching. In one embodiment, the cushioning layer 20 is coupled or adhered to the outer shell 14 of the helmet 12 and the jacket 30 installed thereover. Alternatively, the cushioning layer 20 can be coupled to or adhered to the jacket 30 along all or a portion of their opposing surfaces such that the jacket 30 can be allowed to move relative to the cushioning layer 20. The cushioning layer 20 might also be comprised of a plurality of independent sections (not shown) to enable each of the sections to move with the jacket 30, e.g. each of the sections is coupled to the jacket 30 and moves slightly away from the other sections when the jacket 30 is stretched. If the cushioning layer 20 includes one or more air bladders, those air bladders can be inflated after installation of the jacket 30 in order to tension the jacket 30 for a tight fit around the helmet 12.
The scales 22 are disposed on the outer surface of the jacket 30 in an overlapping manner so as to cover at least a portion of the outer surface of the jacket 30. Preferably, the scales 22 cover substantially the entire outer surface of the jacket 30, but they might be arranged to cover only selected areas or portions of the cushioning layer 20, e.g. areas with the highest propensity for receiving impacts. The scales 22 can be arranged in any desired overlapping manner. In one embodiment, the scales 22 are generally aligned in rows that are laterally offset from adjacent rows such that each scale 22 of a first row overlaps two scales 22 of a second row, as depicted in FIG. 4.
The scales 22 are preferably comprised of a substantially rigid material of sufficient strength and durability to endure repeated impacts of objects with the protective covering 10. Such materials include plastics like ABS or polycarbonate plastics, metals like titanium, ceramic materials, and composite materials, among others. The materials can be further selected to provide a low coefficient of friction or can be coated or treated with additional materials to provide a surface with a low coefficient of friction. Preferably, the coefficient of friction of the scales 22 is less than that of the outer shell 14 of the helmet 12. The materials for the scales 22 might also be configured to provide a desired degree of resiliency to allow the scales 22 to flex or bend when receiving an impact force.
As depicted in FIGS. 6-9, the scales 22 include a shovel-shaped body 31 having a head end 32 and a tail end 34. The head end 32 has an arcuate leading edge and forms a semi-circular body while the tail end 34 is narrower than the head end 32 and terminates in a point directed away from the head end 32. The perimeter of a top surface 36 of the scale 22 is pitched downwardly toward a bottom surface 38 of the scale 22. Similarly, the perimeter of the bottom surface 38 is pitched upward toward the top surface 36 to form a sharp edge around the scale 22. The upward and downward angles of the top and bottom surfaces 36, 28 of the scales 22 may provide mating contact surfaces between the scales 22 when overlapping. The body 31 of the scale 22 can also be at least partially arced or cupped to provide a convex form that is adaptable to a curved surface, e.g. the curved form of the helmet 14. The size and form of the scales 22 is preferably continuous across the protective covering 10 but can be varied. For example, smaller scales 22 might be provided around the periphery of the protective covering 10 associated with areas of the helmet 12 that receive the most impacts while larger scales might be provided in areas associated with the top of the helmet 12 that receive fewer impacts.
FIGS. 10A-E depict a non-exhaustive selection of exemplary alternative forms of the scales 22. As depicted in FIG. 10A, the scales 22A can include a raised ridge 40 among other surface features. The raised ridge 40 may aid to strengthen the scale and/or modify frictional characteristics of the scale 22A. Scales 22B and 22C depict various shapes that might be used for the head ends 32B, 32C thereof and a blunted tail end 34B, 34C, as shown in FIGS. 10B and 10C. A scale 22D depicts a tail end 34D with features configured to receive a strand, thread, or similar element for coupling to the cushioning layer 20. And the scale 22E depicts a scale with a polygonal shape.
With continued reference to FIGS. 8-9, the scales 22 may include a leg 42 extending from the bottom surface 38 thereof and a foot 44 disposed at the distal end of the leg 42. As shown in FIG. 8, the leg 42 may penetrate through an opening in the jacket 30 and the foot 44 may be disposed between the jacket 30 and the cushioning layer 20. The leg 42 is provided with an asymmetrical cross-sectional shape to resist rotation of the scale 22 about an axis aligned along the length of the leg 42. The foot 44 has larger dimensions than that of the hole through which the leg 42 is inserted and thus resists withdrawal of the foot 44 and leg 42 from the jacket 30. The scales 22 are thus coupled to the jacket 30 by inserting the foot 44 through a respective aperture in the jacket 30 in a manner similar to a button.
Alternatively, as shown in FIG. 9, the leg 42 and foot 44 can be configured to couple the scale 22 with the cushioning layer 20. The leg 42 penetrates through the cushioning layer 20 to the foot 44, which is disposed on an opposite side of the cushioning layer 20 from the scale body 31. Again, the foot 44 has larger dimensions than that of the hole through which the leg 42 is inserted and thus resists withdrawal of the foot 44 and leg 42 from the cushioning layer 20. The scales 22 may be coupled to the cushioning layer 20 by inserting the foot 44 through a respective aperture in the cushioning layer 20 in a manner similar to a button or the leg 42 can be passed through a respective aperture in the cushioning layer 20 and the foot 44 coupled to the distal end of the leg 42 from an opposite side of the cushioning layer 20.
In other embodiments, the scales 22 can be coupled to the jacket 30 or cushioning layer 20 by one or more means including glues, sewing, stitching, riveting, welding, or the like. For example, a scale 46 is coupled to the jacket 30 by stitching using one or more threads 48 inserted through the tail end of the scale 46, as depicted in FIG. 11.
The protective covering 10 also includes one or more attachment or retention elements configured to enable coupling of the protective covering 10 with the helmet 12. As depicted in FIG. 2, a substantially rigid insert 50 is provided along a front edge of the jacket 30 of the protective covering 10. The insert 50 provides a coupling location through which one or more fasteners 52 may be inserted to engage receptacles associated with the helmet 12. For example, fasteners 52 associated with mounting the facemask 18 on the helmet 12 might also be employed to couple the insert 50 to the helmet 12. The insert 50 may also reinforce or retain the shape and positioning of the protective covering 10 on the helmet 12. The protective covering 10 may include one or more clips 54, straps, or similar elements to engage the helmet 12 and retain the protective covering 10 in place, particularly on the rear edge of the helmet 12 opposite the insert 50. In another embodiment, the protective covering 10 is adhered or glued to the shell 14 of the helmet 12 or employs elasticity in the cushioning layer 20 to provide a friction fit on the helmet 12.
With continued reference to FIGS. 1-5, application of the protective covering 10 to the helmet 12 and use thereof is described in accordance with embodiments of the invention. The protective covering 10, as depicted in FIG. 2, is installed onto the outer shell 14 of the helmet 12 (FIG. 1), and may be applied to an existing helmet 12 as a retrofit thereof or may be applied to a new helmet 12 during its manufacture. In one embodiment, the cushioning layer 20 is installed over the outer shell 14 of the helmet 12 and may be secured thereto using adhesive, fasteners or the like. The jacket 30, with the scales 22 attached thereto is then installed over the cushioning layer 20 and coupled to the helmet 12 by inserting the fasteners 52 associated with the facemask 18 through the insert 50. Clips 54 disposed along edges of the jacket 30 are also engaged with at least the rearward edge of the helmet 12.
In another embodiment, the cushioning layer 20, jacket 30 and scales 22 are assembled together first to form the protective covering 10 which is then fastened to the helmet 12 using the insert 50, fasteners 52 and clips 54 as described above. In yet another embodiment, a layer of glue or adhesive is disposed on the outer shell 14 of the helmet 12 prior to placing the protective covering 10 on the shell 14. The protective covering 10 can thus be retained on the helmet 12 via the glue. In another embodiment, the protective covering 10 is maintained on the helmet 12 by friction-fit. One or more frictional materials or features might be disposed on an inner surface of the cushioning layer 20 to aid the friction-fit retention of the protective covering 10 on the helmet 12.
With reference now to FIG. 5, in use the protective covering 10 provides protection against objects impacting the helmet 12. As shown in FIG. 5, impact between a first helmet 12 a and a second helmet 12 b, each having a protective covering 10 a, 10 b, causes the scales 22 a, 22 b to be deflected relative to one another. The deflection of the scales 22 a, 22 b provides a flexible outer surface to enable at least a portion of the impact forces to be absorbed by the cushioning layers 20 a, 20 b. The rigidity of the scales 22 a, 22 b may also aid to distribute or deflect the impact forces across a larger area of the cushioning materials. The scales 22 a, 22 b are depressed into their respective cushioning layers 20 a, 20 b to compress the cushioning materials. As such, at least a portion of the forces associated with the impact is absorbed by the cushioning layers 20 a, 20 b. The resiliency of the cushioning layers 20 a, 20 b returns the scales 22 a, 22 b to their original positions upon removal of the impact forces.
The rigidity and low frictional properties of the scales 22 a, 22 b aid deflection of the impact between the helmets 12 a, 12 b. The selection of materials for the scales 22 a, 22 b having a low coefficient of friction enables the scales 22 a, 22 b of the opposing helmets 12 a, 12 b to more easily slide along one another. The configuration of the scales 22 a, 22 b, including the dimensions and surface features like ridges and angled edges may also reduce frictional forces seen between the protective covering 10 and an opposing object. For example, the combined surface of the plurality of scales 22 and any ridges or surface features thereon provides less contacting surface area between the protective covering 10 and an impacting object than a smooth or continuous surface; there is thus less frictional resistance to sliding contact between the protective covering 10 and the object. Impacts may thus be more often characterized as glancing-style blows that transfer less energy from the impact to the head and/or brain of the participants.
The scales 22 a, 22 b might also operate to absorb at least a portion of the impact forces. The scales 22 a, 22 b can be configured to at least partially flex or bend when impacted. Such flexing may operate to absorb energies from impacts.
Many different arrangements of the various components depicted, as well as components not shown, are possible without departing from the scope of the claims below. Embodiments of the technology have been described with the intent to be illustrative rather than restrictive. Alternative embodiments will become apparent to readers of this disclosure after and because of reading it. Alternative means of implementing the aforementioned can be completed without departing from the scope of the claims below. Certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations and are contemplated within the scope of the claims.

Claims

What is claimed is:

1. A protective covering for a helmet comprising:

a cushioning layer configured to cover at least a portion of an exterior surface of a substantially rigid outer shell of a helmet; and

a plurality of overlapping scales overlying the cushioning layer.

2. The protective covering as in claim 1, wherein said scales are deflectable relative to one another by compressing said cushioning layer to at least partially absorb an impacting force.

3. The protective covering as in claim 1 and further comprising one or more of a fastener, a clip, a strap, and a glue configured to retain said protective covering on the helmet.

4. The protective covering as in claim 1 and further comprising a jacket extending at least partially over an outer surface of said cushioning layer.

5. The protective covering as in claim 4, wherein said plurality of scales is coupled to said jacket.

6. The protective covering as in claim 5, wherein said jacket is formed of fabric.

7. The protective covering as in claim 6 wherein said fabric is at least slightly resilient to allow said jacket to be stretched across the cushioning layer and shell of the helmet.

8. The protective covering as in claim 5 and further comprising one or more of a fastener, a clip, a strap, and a glue configured to secure said jacket to the helmet.

8. The protective covering as in claim 5, wherein one or more of said scales includes a scale body, a leg extending from an underside of said scale body, and a foot disposed at a distal end of said leg, and wherein said leg extends through said jacket and said foot prevents withdrawal of said leg from said cushioning layer.

9. The protective covering as in claim 1, wherein one or more of said scales includes a scale body comprising a head and a tail, said head extending to overlie at least a portion of the tail of an adjacent scale.

10. The protective covering as in claim 9, wherein said head of said scale has a semicircular form extending in a first direction and said tail has a narrow, pointed form and extends in a second direction opposite said first direction.

11. The protective covering as in claim 1, wherein one or more of said scales includes a top surface and a bottom surface, and wherein at least a portion of a perimeter of said top surface is sloped toward said bottom surface and wherein at least a portion of a perimeter of said bottom surface is sloped toward said top surface.

12. The protective covering as in claim 1, wherein one or more of said scales includes a raised ridge along at least a portion of a top surface of the respective scale.

13. The protective covering as in claim 1, wherein one or more of said scales includes a scale body with a bottom surface that is at least partially cupped.

14. The protective covering as in claim 1, wherein a thickness of said cushioning layer is greater in regions of the helmet with a higher propensity for receiving an impact and less in regions of the helmet with a lower propensity for receiving an impact.

15. A helmet with a protective covering comprising:

a substantially rigid shell having dimensions sufficient to receive a head of a wearer at least partially therein;

an inner cushioning disposed on an interior surface of said shell and configured to provide padding between a wearer's head and said shell;

an external cushioning layer disposed on at least a portion of an exterior surface of said shell and coupled to said shell; and

a plurality of overlapping scales overlying an exterior surface of said cushioning layer.

16. The helmet as in claim 15, wherein said scales are deflectable relative to one another by at least partially compressing said external cushioning layer upon receipt of an impact force.

17. The helmet of claim 15, wherein said sc ales are configured to provide a lower coefficient of friction than that of a continuous surface comprised of the same material as said scales.

18. The helmet as in claim 15 and further including a jacket covering at least a portion of an outer surface of said cushioning layer, and wherein said plurality of overlapping scales are secured to said jacket.

19. The helmet as in claim 18, wherein one or more of said scales includes a scale body, a leg extending from an underside of said scale body, and a foot disposed at a distal end of said leg, and wherein said leg extends through said jacket, said foot disposed between said jacket and said external cushioning layer and preventing withdrawal of said leg from said jacket.

20. The helmet as in claim 18 and further including one or more substantially rigid members that are useable to couple said jacket to said substantially rigid shell.