MULTIFACETED PROTECTIVE HELMETS

Abstract

In some embodiments, a protective helmet includes an outer shell including a sun visor, the outer shell comprising an outer surface having a plurality of non-parallel facets.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to co-pending U.S. Provisional Application Ser. No. 61/843,599, filed Jul. 8, 2013, which is hereby incorporated by reference herein in its entirety.

NOTICE OF GOVERNMENT-SPONSORED RESEARCH

This invention was made with Government support under grant or contract number W911NF-04-2-0018 awarded by the Army Research Laboratory. The Government has certain rights in the invention.

BACKGROUND

Protective helmets are worn in many situations to protect the head from injury that can result from impact with a static or dynamic object. Such helmets are often worn by players of various sports. For example, baseball players typically wear helmets when they are batting to protect their head from the pitched baseball.

While current protective helmets offer protection to the wearer, improvements in protection are always welcome because of the potentially serious nature of head injuries.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be better understood with reference to the following figures. Matching reference numerals designate corresponding parts throughout the figures, which are not necessarily drawn to scale.

FIG. 1A is a top perspective view of a first embodiment of a faceted protective helmet.

FIG. 1B is a front view of the protective helmet of FIG. 1A.

FIG. 2A is a top perspective view of a second embodiment of a faceted protective helmet.

FIG. 2B is a side view of the protective helmet of FIG. 2A.

FIG. 3A is a side view of a third embodiment of a faceted protective helmet.

FIG. 3B is a top perspective view of the protective helmet of FIG. 3A.

FIG. 4 is a schematic view of a syntactic material that can be used to form an outer shell of a protective helmet.

DETAILED DESCRIPTION

Disclosed herein are protective helmets that offer improved protection to the wearer. As described below, the helmets include faceted outer surfaces that reduce the potential for normal impacts and therefore dissipate energy that might otherwise be transmitted to the wearer's head.

In the following disclosure, various specific embodiments are described. It is to be understood that those embodiments are example implementations of the disclosed inventions and that alternative embodiments are possible. All such embodiments are intended to fall within the scope of this disclosure.

FIGS. 1A and 1B illustrate a first embodiment of a protective helmet 10, which can be configured as a sports helmet. As shown in these figures, the helmet 10 generally comprises an outer shell 12 that is sized and configured to surround a wearer's head from the base of the skull to the forehead and from one ear to the other. In other words, the outer shell 12 is sized and configured to surround all but the wearer's face. The helmet 10 can also include a relatively soft inner liner (not shown) that includes one or more flexible and/or resilient pads that provide cushioning to the head and dissipate energy from impacts.

The outer shell 12 is generally rigid and can be made of any material that provides impact protection to the wearer. In some embodiments, the shell 12 is made of a polymeric material that is approximately 1 to 4 mm thick. The polymeric material that is used can depend upon the application of the helmet and the level of protection that is required. In some embodiments, the shell 12 is made of a long fiber thermoplastic (LFT) material. The use of LFTs is desirable because they provide high levels of protection like continuous fiber reinforced composites but can be processed using traditional plastics molding equipment. Therefore, parts can be manufactured at medium- to high-volume rates with excellent consistency and repeatability. Long fibers (e.g., fiber lengths of about 3 mm to 50 mm) provide an elastic modulus and a tensile strength that is up to approximately 80% of that obtained using continuous fibers.

In some embodiments, LFT materials are formed by hot melt-impregnating continuous reinforcing fiber into a thermoplastic resin. The mixture can be cooled and formed (e.g., chopped) into discontinuous reinforcing fiber pellets. The amount of thermoplastic resin can be approximately 50 to 99 weight % of the LFT material and the amount of continuous reinforcing fiber (and once cut into the discontinuous reinforcing fiber) can be approximately 0.1 to 50 weight % of the LFT material. Example thermoplastic resins include polyamide, acrylonitrile butadiene styrene (ABS), polyphenylene sulfide, polypropylene, poly ether ether ketone, poly ether ketone, polyethylene, poly butylene terephthalate, poly ethylene terephthalate, polyoxymethylene, and combinations (mixtures) thereof. Example reinforcing fibers include carbon, glass, aramid, polypropylene, polyethylene, basalt, poly{diimidazo pyridinylene (dihydroxy) phenylene}, natural fibers such as flax, kenaf, bamboo, jute, sisal, and combinations (mixtures) thereof.

In other embodiments, the outer shell 12 is made of a non-reinforced polymer material. Examples of such materials include polyamide, ABS, polyphenylene sulfide, polypropylene, poly ether ether ketone, poly ether ketone, polyethylene, poly butylene terephthalate, poly ethylene terephthalate, polyoxymethylene, or combinations (mixtures) thereof.

In still other embodiments, the outer shell 12 is made of a syntactic material that comprises a plurality of microspheres (also referred to as cenospheres or microballoons) that are compounded with a thermoplastic resin. Such a material is schematically depicted in FIG. 4, which shows a syntactic material 90 that comprises microspheres 92 compounded with a resin 94. As is apparent from FIG. 4, the microspheres 92 are small, hollow spherical elements having an interior void 96 that is enclosed by a thin outer shell 98. Because much of the volume of the microspheres 92 is void space (e.g., air), the microspheres and the syntactic material 90 are very lightweight. By way of example, the syntactic material 90 has a density of approximately 0.3 to 0.9 g/cc and the microspheres 92 comprise approximately 30% to 35% of the material by volume percentage. In some embodiments, the microspheres 92 have a nominal outer diameter of approximately 0.1 mm to 1.0 mm and the shells 98 have a thickness of approximately 20 μm to 200 μm. The microsphere shells 98 can be made of substantially any material that can be formed (e.g., blown) into a very small hollow sphere. By way of example, the microsphere's shells 98 can be made of a polymeric, ceramic, glass, or metal material.

The resin 94 can comprise a polymeric resin. In some embodiments, the resin is a thermoplastic resin comprising an olefin, such as polypropylene, polyethylene, or combinations (mixtures) thereof. Alternatively, the thermoplastic resin can comprise an engineered polymer, such as polyamide, polyether ether ketone (PEEK), polyether ketone (PEK), polyethyleneimine (PEI), polyphenylene sulfide (PPS), or combinations (mixtures) thereof.

The protective helmet 10 can be used in substantially any context. In some embodiments, the helmet 10 is used to protect the wearer's head during sports activities. In the specific example illustrated in FIGS. 1A and 1B, the helmet 10 takes the form of a baseball batting helmet that includes one or more ear flaps 14 and a sun visor 16. It is noted that, although a baseball helmet is shown in FIGS. 1A and 1B, the helmet 10 could be configured for use in other sports, including football, hockey, lacrosse, field hockey, polo, bicycling, motorsports, and the like. Moreover, the helmet 10 could be configured for non-sports applications, including military and combat applications.

Irrespective of its particular application, the outer surface 18 of the shell 12 comprises a plurality of facets 20 that lie in non-parallel planes. In some embodiments, the facets 20 are generally planar (i.e., not curved) and reduce the likelihood that a projectile will impact the shell 12 from a normal (perpendicular) direction. Accordingly, such projectiles will have the tendency to skirt or skip across the surface 18 of the shell 12. In some embodiments, each facet 20 defines a similar geometric shape. In some embodiments, each facet 20 is triangular and therefore includes three linear sides. In such cases, the triangles can have three equal angles (equilateral triangle), two equal angles (isosceles triangle), or no equal angles (scalene triangle). In some embodiments, the groups of facets 20 define multifaceted prisms on the surface 18 of the shell 12, such as the hexagonal, six-facet prism 22 highlighted in FIG. 1A and/or the pentagonal five-facet prism 24 highlighted in FIG. 1B. In both cases, the prism 22, 24 defines a raised central point 26 that is formed by the corners of the facets 20 that define the prism.

In some embodiments, each facet 20 has a nominal dimension of approximately 1 to 3 inches. In the example embodiment of FIGS. 1A and 1B, in which the facets 20 are triangular, this dimension can be the length of one or more sides of the triangles. In other embodiments, in which the facets are not triangular, the nominal dimension can be a maximum dimension (length or width) of the facet. By way of example, the outer surface 18 of the shell 12 can comprise approximately 80 to 150 facets 20.

As shown in FIGS. 1A and 1B, the facets 20 can extend across much of the outer surface 18 of the shell 12 but not all of it. In the embodiment of these figures, the facets 20 do not extend to the ear flaps 14 or the sun visor 16.

With reference to FIG. 1A, the outer shell 12 also includes ventilation openings 28 that enable air to reach the head and heat and vapor to escape the helmet 10. In some embodiments, the openings 28 are configured as elongated linear slits that extend along the length of the sides (edges) of two or more facets 20. In the example embodiment of FIGS. 1A and 1B, the shell 12 includes four such openings 28 arranged in a spaced configuration near the top of the shell.

With further reference to FIG. 1A, the outer shell 12 also includes ear openings 30 that are formed in the ear flaps 14. In the illustrated embodiment, the ear openings 30 have a general teardrop shape in which at least one edge of the openings 30 is curved.

FIGS. 2A and 2B illustrate a further embodiment of a protective helmet 40. The helmet 40 is similar in many ways to the helmet 10 shown in FIGS. 1A and 1B. Therefore, the helmet 40 generally comprises an outer shell 42 that can be made of one of the materials described above in relation to the outer shell 12. The outer shell 42 includes ear flaps 44 and a sun visor 46 and comprises an outer surface 48 that has a plurality of facets 50 that define multifaceted prisms 52 that each includes a raised central point 54 formed by the corners of the facets. The outer shell 42 further includes ventilation openings 56 and ear openings 58. Unlike the outer shell 12, however, the outer shell 40 includes facets 50 that extend across the ear flaps 44. In addition, the ear openings 58 are triangular instead of being teardrop shaped.

FIGS. 3A and 3B illustrate yet another embodiment of a protective helmet 60. The helmet 50 is similar in many ways to the helmet 40 shown in FIGS. 2A and 2B. Therefore, the helmet 60 generally comprises an outer shell 62 that can be made of one of the materials described above in relation to the outer shell 12. The outer shell 62 includes ear flaps 64 and a sun visor 66 and comprises an outer surface 68 that has a plurality of facets 70 that define multifaceted prisms 72 that each includes a raised central point 74 formed by the corners of the facets. The outer shell 62 further includes ventilation openings 76. Unlike the helmet 40, however, openings 76 of the helmet 60 are arranged in an alternative pattern in which six ventilation openings 28 are arranged in an “X” pattern that is visible from the top and rear of the helmet (see FIG. 3B). The “X” pattern is formed by two crossed lines of openings 28, with each opening being arranged with its longitudinal axis aligned with its line. In addition, the helmet 60 includes facets 70 that extend across the sun visor 66. Furthermore, the helmet 60 has an alternative ear opening pattern in which each ear flap 44 includes a first or primary ear opening 78 and a second or secondary ear opening 80. In the illustrated embodiment, the first ear opening 78 is larger than the secondary ear opening 80. In addition, the primary ear opening 78 is triangular while the secondary ear opening is elongated and linear.

In each of the above-described embodiments, the inner surface of the outer shell 12 can either be faceted in a similar manner to the outer surface 18 or can be smooth similar to conventional helmets. Regardless, it is reiterated that a relatively soft inner liner comprising one or more flexible and/or resilient pads can be provided within the shell to cushion the wearer's head and/or dissipate direct or rotational force.

Claims

1. A protective helmet comprising:

an outer shell including a sun visor, the outer shell comprising an outer surface having a plurality of non-parallel facets.

2. The helmet of claim 1, wherein the facets are generally planar.

3. The helmet of claim 2, wherein the facets have a geometric shape.

4. The helmet of claim 3, wherein the facets are triangular.

5. The helmet of claim 1, wherein groups of facets on the outer surface form multifaceted prisms having a raised center point.

6. The helmet of claim 5, wherein the prisms are pentagonal.

7. The helmet of claim 5, wherein the prisms are hexagonal.

8. The helmet of claim 1, wherein the facets have a nominal dimension of approximately 1 to 3 inches.

9. The helmet of claim 1, wherein the facets have a maximum dimension of 1 to 3 inches.

10. The helmet of claim 1, wherein the outer shell further includes an ear flap.

11. The helmet of claim 10, wherein the ear flap includes an ear opening.

12. The helmet of claim 1, wherein the outer shell further includes ventilation openings.

13. The helmet of claim 12, wherein at least one ventilation opening is formed along the sides of two adjacent facets.

14. The helmet of claim 1, wherein the outer shell is made of a polymeric material.

15. The helmet of claim 14, wherein the outer shell is made of a fiber-reinforced polymeric material.

16. The helmet of claim 14, wherein the outer shell is made of a syntactic material that includes a plurality of microspheres.

17. A baseball helmet comprising:

an outer shell adapted to surround a wearer's head, the shell including an ear flap that is adapted to cover an ear of the wearer and a visor that is adapted to shield the wearer's eyes from light, wherein the shell comprises an outer surface having a plurality of non-parallel, planar, triangular facets, wherein groups of facets form multifaceted prisms on the outer surface having a raised center point.

18. The baseball helmet of claim 17, wherein the prisms are pentagonal or hexagonal.

19. The baseball helmet of claim 17, wherein the ear flap includes an ear opening.

20. The baseball helmet of claim 17, wherein the outer shell further includes ventilation openings.