WO2016077501A1 - Casques de protection comportant des revêtements d'absorption d'énergie - Google Patents

Casques de protection comportant des revêtements d'absorption d'énergie Download PDF

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Publication number
WO2016077501A1
WO2016077501A1 PCT/US2015/060225 US2015060225W WO2016077501A1 WO 2016077501 A1 WO2016077501 A1 WO 2016077501A1 US 2015060225 W US2015060225 W US 2015060225W WO 2016077501 A1 WO2016077501 A1 WO 2016077501A1
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WO
WIPO (PCT)
Prior art keywords
columns
helmet
energy
energy absorbing
layers
Prior art date
Application number
PCT/US2015/060225
Other languages
English (en)
Inventor
Dean Sicking
David LITTLEFIELD
Kenneth WALLS
Original Assignee
The Uab Research Foundation, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by The Uab Research Foundation, Inc. filed Critical The Uab Research Foundation, Inc.
Priority to US15/526,045 priority Critical patent/US20170303623A1/en
Priority to CA2966656A priority patent/CA2966656A1/fr
Publication of WO2016077501A1 publication Critical patent/WO2016077501A1/fr

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Classifications

    • A—HUMAN NECESSITIES
    • A42—HEADWEAR
    • A42B—HATS; HEAD COVERINGS
    • A42B3/00—Helmets; Helmet covers ; Other protective head coverings
    • A42B3/04—Parts, details or accessories of helmets
    • A42B3/06—Impact-absorbing shells, e.g. of crash helmets
    • A42B3/062—Impact-absorbing shells, e.g. of crash helmets with reinforcing means
    • A42B3/063—Impact-absorbing shells, e.g. of crash helmets with reinforcing means using layered structures
    • A42B3/064—Impact-absorbing shells, e.g. of crash helmets with reinforcing means using layered structures with relative movement between layers
    • A—HUMAN NECESSITIES
    • A42—HEADWEAR
    • A42B—HATS; HEAD COVERINGS
    • A42B3/00—Helmets; Helmet covers ; Other protective head coverings
    • A42B3/04—Parts, details or accessories of helmets
    • A42B3/10—Linings
    • A42B3/12—Cushioning devices
    • A—HUMAN NECESSITIES
    • A63—SPORTS; GAMES; AMUSEMENTS
    • A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
    • A63B71/00—Games or sports accessories not covered in groups A63B1/00 - A63B69/00
    • A63B71/08—Body-protectors for players or sportsmen, i.e. body-protecting accessories affording protection of body parts against blows or collisions
    • A63B71/10—Body-protectors for players or sportsmen, i.e. body-protecting accessories affording protection of body parts against blows or collisions for the head
    • A—HUMAN NECESSITIES
    • A42—HEADWEAR
    • A42B—HATS; HEAD COVERINGS
    • A42B3/00—Helmets; Helmet covers ; Other protective head coverings
    • A42B3/04—Parts, details or accessories of helmets
    • A42B3/06—Impact-absorbing shells, e.g. of crash helmets
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41—WEAPONS
    • F41H—ARMOUR; ARMOURED TURRETS; ARMOURED OR ARMED VEHICLES; MEANS OF ATTACK OR DEFENCE, e.g. CAMOUFLAGE, IN GENERAL
    • F41H1/00—Personal protection gear
    • F41H1/04—Protection helmets

Definitions

  • Protective headgear such as helmets
  • Current helmet certification standards are based on testing parameters that were developed in the 1960s, which focus on the attenuation of linear impact and prevention of skull fracture.
  • An example of a linear impact is a football player taking a direct hit to his helmet from a direction normal to the center of his helmet or head.
  • headgear design has always been on attenuating such linear impacts
  • multiple lines of research in both animal models and biomechanics suggest that both linear impact and rotational acceleration play important roles in the pathophysiology of brain injury.
  • rotational acceleration is greatest when a tangential blow is sustained. In some cases, the rotational acceleration from such blows can be substantial.
  • a football player's facemask can act like a lever arm when impacted from the side, and can therefore apply large torsional forces to the head, which can easily result in brain trauma.
  • Fig. 1 is a cross-sectional side view of an embodiment of a protective helmet.
  • Fig. 2A is a front view of an embodiment of an energy absorber that can be used in the helmet of Fig. 1 .
  • Fig. 2B is a side view of the energy absorber of Fig. 2A.
  • Fig. 3 is a partial detail view of an energy absorbing column of the energy absorber of Fig. 2.
  • Fig. 4 is a side view of a further embodiment of an energy absorber that can be used in the helmet of Fig. 1 .
  • Fig. 5 is a side view of a compressed energy absorber illustrating bending and buckling of its energy absorbing columns.
  • Fig. 6A is a bottom view of a protective helmet of the type shown in Fig. 1 immediately prior to impact from another helmet.
  • Fig. 6B is a bottom view of the protective helmet of Fig. 6A during an impact from another helmet.
  • Fig. 7 is a side view of a further embodiment of an energy absorber that can be used in the helmet of Fig. 1 .
  • Fig. 8A is a cross-sectional side view of a protective helmet incorporating an energy absorbing outer shell immediately prior to an impact.
  • Fig. 8B is a cross-sectional side view of the protective helmet of Fig. 8B during the impact.
  • Fig. 9 is a rear perspective view of a first embodiment of a passive helmet tether system.
  • Fig. 10 is a rear perspective view of a second embodiment of a passive helmet tether system.
  • Fig. 1 1 is a rear perspective view of a third embodiment of a passive helmet tether system.
  • Fig. 12 is a rear perspective view of a first embodiment of an active helmet tether system.
  • Fig. 13 is a rear perspective view of a second embodiment of an active helmet tether system.
  • energy absorbing systems that comprise means for absorbing energy from impacts to a protective helmet that minimize both translational and rotational accelerations experienced by the head of the helmet wearer.
  • these means comprise an inner liner that includes energy absorbing columns that are designed bend and buckle to attenuate both translational and rotational accelerations.
  • the means comprise energy absorbing outer shell that locally deforms upon hard impacts to absorb energy.
  • the means comprise an energy absorbing tether system that limits linear movement and rotation of the helmet upon hard impact.
  • Described below are energy absorbing systems that can be incorporated into protective helmets that not only address linear forces but also tangential forces that cause the highest shear strains on the brain and the brain stem. By optimizing protection from both linear impacts and rotational acceleration, the transmission of shear force to the brain from head impacts can be reduced and so can the incidence of brain injury, such as concussion.
  • a protective helmet can be provided with an energy absorbing inner liner that utilizes energy absorbing columns having various lengths and/or cross-sectional dimensions that are sandwiched between two elastomeric layers.
  • the use of columns of varying lengths and/or cross-section dimensions enables protection against impacts over a range of energy levels. When columns of different lengths are used, low-energy impacts will activate only the tallest columns, which are connected to both layers, resulting in low translational accelerations. Higher energy impacts, however, will also activate shorter columns, which are connected to only one layer to prevent bottoming out and unacceptably high translational accelerations.
  • the liner can be designed to provide optimal stiffness by tuning the distribution of columns to control the peak accelerations applied to the wearer's head during impact.
  • the inner liner uses controlled buckling and bending of the columns to mitigate both linear and rotational accelerations experienced by the wearer's head.
  • Traditional column buckling is a velocity-dependent process that produces high initial forces that drop very low as the column deforms. This fundamental behavior must be overcome if columns are to become an efficient energy absorber for use in protective helmets and other protective equipment.
  • One important advantage of precise column buckling that makes it attractive for use as a helmet liner is the directionality of its resistance forces during oblique impacts that apply rotational moments to the helmet. During this type of impact, the top of the column pushes the helmet in the direction of the applied moment while pushing the player's head in the opposite direction.
  • An advance of the disclosed liners is that linear impact dissipation can be optimized without adversely affecting the rotational behavior of the columns.
  • the disclosed inner liner overcomes this problem using multiple features.
  • the columns of the inner liner can be made of an elastomeric material that provides some level of axial compression during the period in which buckling is initiated to compensate for the magnitude of the inertial spike.
  • the columns can be eccentric relative to the layers between which they lie to reduce the load required to initiate column buckling.
  • These eccentricities take the form of a misalignment of the column ends from the normal direction of the layers so that the columns will have a moment applied upon the onset of loading.
  • This misalignment also results in additional stroke because it can cause the column halves to fold beside themselves as they collapse rather than stacking on top of themselves.
  • the curvature of the inner liner due to the curved nature of the helmet results in further eccentricity in the columns because it is likely that only a small portion of the activated columns will be normal to the impact direction, thus any inertial forces coming from these columns would be small in comparison to the overall forces generated by the sum of activated columns.
  • the column lengths can be varied. Varying column lengths accomplishes two goals. Firstly, it spreads out the inertial impulse to eliminate the high inertial spike during the early stages of impact. Secondly, it enables the liner stiffness to be increased with higher deflections.
  • Fig. 1 illustrates an example embodiment of a protective helmet 10 that is designed to attenuate both linear impact and rotational accelerations.
  • the helmet 10 shown in Fig. 1 is generally configured as an American football helmet. Although that particular configuration is shown in the figure and other figures of this disclosure, it is to be understood that a football helmet is shown for purposes of example only and is merely representational of an example protective helmet. Therefore, the helmet need not be limited to use in football. Other sports applications include baseball and Softball batting helmets, lacrosse helmets, hockey helmets, ski helmets, bicycling and motorcycle helmets, and racecar helmets. Furthermore, the helmet need not even be used in sports. For example, the helmet could be designed as a construction or military helmet.
  • the principles described herein can be extended to protective equipment other than helmets.
  • features described below can be incorporated into protective pads or armor, such as shoulder pads, hip pads, thigh guards, shin guards, cleats, and other protective equipment in which energy absorption could be used to protect the wearer.
  • the helmet 10 generally includes an outer shell 12 and an inner liner 14.
  • the shell 12 is shaped and configured to surround the wearer's head with the exception of the face.
  • the shell 12 when worn, extends from a point near the base of the wearer's skull to a point near the wearer's brow, and extends from a point near the rear of one side of the wearer's jaw to a point near the rear of the other side of the wearer's jaw.
  • the shell 12 is unitarily formed from a generally rigid material, such as a polymer or metal material. Example materials are described below in relation to Figs. 9A and 9B.
  • the shell includes an outer surface 16 and an inner surface 18.
  • the shell 12 can further include one or more ear openings 20 that extend through the shell from the outer surface 16 to the inner surface 18.
  • the ear openings 20 are provided on each side of the shell 12 in a position in which they align with the wearer's ears when the helmet 10 is donned.
  • the shell 12 can include other openings that serve one or more purposes, such as providing airflow to the wearer's head.
  • a facemask 22 can be secured to the front of the helmet 10 to protect the face of the wearer.
  • the facemask 22 can comprise one or more rod-like segments that together form a protective lattice or screen.
  • the facemask 22 can, for example, be attached to the helmet 10 at points that align with the forehead and jaw of the wearer when the helmet is worn.
  • the facemask 22 can be attached to the helmet 10 using screws (not shown) that thread into the shell 12 or into fastening elements (not shown) that are attached to the helmet.
  • screws not shown
  • the facemask 22 can be replaced with a face shield or other protective element, if desired.
  • the inner liner 14 generally comprises one or more pads that sit between the shell 12 and the wearer's head when the helmet 10 is worn.
  • each of the pads is removable from the helmet.
  • the pads can be configured to releasably attach to the inside surface 18 of the helmet shell 16 with snap, T-nut, or hook-and-loop fasteners.
  • the pads include a top pad 24, multiple lateral pads 26, 28, and 30, a front pad 32, a rear pad 34, and jaw pads 36.
  • the top pad 24 is adapted to protect the top of the wearer's head.
  • the top pad 24 is elongated in a direction that extends along the sagittal plane of the wearer so as to extend from a rear top portion of the head to a front top portion of the head.
  • the top pad 24 is further curved to generally follow the curvature of the wearer's head. Accordingly, the top pad 24 forms a concave inner surface that is adapted to contact the wearer's head.
  • the lateral pads 26-30 are adapted to protect the sides of the wearer's head.
  • the lateral pads 26-30 extend from the edges of the wearer's face to points behind (and above) the user's ears.
  • the lateral pads 26-30 are curved to follow the curvature of the shell 12 and the wearer's head. Accordingly, the lateral pads 26-30 form concave inner surfaces that are adapted to contact the wearer's head.
  • the front pad 32 is positioned within the outer shell 12 so as to protect the forehead of the wearer. Like the other pads, the front pad 32 is curved to follow the curvature of the wearer's head. The forward pads 30 therefore form concave inner surfaces that are adapted to contact the wearer. The rear pad 34 is adapted to protect the rear of the wearer's head. The rear pad 28 is also curved to follow the curvature of the wearer's head and forms a concave inner surface that is adapted to contact the wearer's head.
  • the jaw pads 36 are adapted to protect the jaw of the wearer. As with the other pads, the jaw pad 36 can curved to follow the curvature of the wearer's head and forms a concave inner surface that is adapted to contact the wearer's head.
  • each of the pads comprise an outer energy absorber 40 that is adapted to absorb translational and rotational energy from helmet impacts and an inner cushion 42 that is adapted to provide comfort to the wearer's head.
  • the energy absorbers 40 releasably attach to the inner surface 18 of the shell 12. Details about the construction of the energy absorbers 40 are provided below in relation to Figs. 2- 8. It suffices to say at this point, however, that the energy absorbers 40 include energy absorbing columns 44 that dissipate translational and rotational accelerations.
  • the inner cushions 42 of the pads contact or are at least adjacent to the wearer's head and/or face when the helmet 10 is donned.
  • the cushions 42 can have any construction that is comfortable for the wearer.
  • the cushions 42 are foam cushions. In other embodiments, the cushions 42 are air bladder cushions.
  • Figs. 2A and 2B illustrate an example energy absorber 50 that can be used in a pad that forms part of a helmet liner, such as the inner liner 14 shown in Fig. 1 .
  • the energy absorber 50 generally comprises a first or inner layer 52, an opposed second or outer layer 54, and a plurality of energy absorbing columns 56 that are provided between the layers, which can bend and buckle to absorb energy.
  • the inner and outer layers 52, 54 comprise thin, generally planar members that are curved to conform to the curvature of the human head and the outer shell 12. In some embodiments, the layers 52, 54 have similar curvatures.
  • the inner layer 52 comprises an inner surface 58 that faces the outer layer 54 and an outer surface 60 that faces the wearer's head and provides a surface to which an inner cushion 42 can be attached.
  • the outer layer 52 comprises an inner surface 62 that faces the inner layer 52 and an outer layer 64 that can be attached to the inner surface 18 of the outer shell 12.
  • the energy absorbing columns 56 can comprise elongated cylindrical members that are substantially perpendicular to the inner and outer layers 52, 54. As is apparent in Figs. 2A and 2B, the columns 56 can have various lengths or heights. Relatively long columns 66 connect the inner and outer layers 52, 54. Such columns 66 are attached at a proximal end (nearest the wearer's head) to the inner layer 52 and are attached at a distal end (nearest the shell 12) to the outer layer 54. Shorter columns 68 are only attached to one of the layers 52, 54. In the illustrated embodiment, the proximal ends of the shorter columns 68 are attached to the inner layer 52 while the distal ends of those columns are free ends. In addition to the lengths, the cross-sectional dimensions of the columns 56 can be varied.
  • the energy absorber 50 can comprise columns of several different lengths.
  • the energy absorber 50 could incorporate columns 56 of 2, 3, 4, 5, or more different lengths, in which case the energy absorber provides multiple stages of energy dissipation.
  • relative mild impacts may only affect the longest columns 56 (i.e., the first stage of the energy absorber 50) while stronger impacts may affect columns of shorter lengths (i.e., other stages of the energy absorber).
  • This multi-stage approach provides increased stiffness as the deflection of the energy absorber 50 increases, as well as reduction in the inertial spike that comes prior to the onset of buckling in the columns 56.
  • the columns 56 are arranged within the energy absorber 50 in a manner that minimizes interaction between adjacent columns to minimize the possibility of the columns stacking on top of one another as the energy absorber compresses.
  • the thicknesses of the inner and outer layers 52, 54, the lengths and cross- sectional dimensions of the columns 56, and the ratio of columns attached to both layers versus attached to only one layer can be tailored to achieve a desired load capacity for the energy absorber 50 and the pad in which it will be used.
  • Thicker layers 52, 54 will increase the load capacity of the columns 56 because of the stiffened end conditions, thereby enabling the use of thinner columns.
  • thicker layers 52, 54 will also increase the overall mass of the inner liner 14 because the layers represent the highest volume of material in the system while also reducing the useable stroke.
  • the energy absorbers 50 it is important to optimize the energy absorbers 50 to provide the desired outcome at each location within the helmet 10, taking into account factors such as available stroke, coverage area in the impact location, frequency of impact in the protected location, and overall liner mass.
  • the front pad 32 (Fig. 1 ) may have larger diameter columns and a higher ratio of attached columns than other pads in the liner 14 to increase the pad stiffness due to the inherent weakness in the outer shell at that location and the increased need for protection in the frontal region due to the increased likelihood of impacts in that location.
  • the outer layer 54 has a thickness of approximately 0.5 to 3 mm and may contain holes for fasteners or ventilation.
  • the inner layer 52 has a thickness of approximately 0.5 to 2.5 mm.
  • the energy absorbing columns 56 that are attached to both the inner and outer layers 52, 54 have lengths of approximately 18 to 65 mm and cross- sectional dimensions (e.g., diameters) of approximately 3 to 7 mm, while the columns that are attached to only one of the layers have lengths of approximately 8 to 55 mm and cross-sectional dimensions (e.g., diameters) of approximately 2 to 6 mm.
  • the fraction of columns 56 that are connected to both layers 52, 54 is approximately 15 to 40%, but can be increased to as much as 100% if the pad will undergo consistent loading and does not need to provide protection against a variety of impact conditions. While the columns 56 are illustrated in Figs. 2A and 2B as having constant cross-sectional dimensions along their lengths, it is noted that these dimensions can vary along the lengths of the columns. For example, one or more columns 56 can have a larger cross-section at its base than at other points along its length.
  • the columns 56 can be slightly eccentric to reduce the magnitude of the inertial spike that occurs upon impact.
  • This eccentricity can come in the form of an angling of the columns 56 from the direction normal to the inner surface of the inner and/or outer layers 52, 54.
  • Fig. 3 illustrates an example of this form of eccentricity.
  • a column 56 is offset from the normal direction of the inner surface 58 of the inner liner 52 by an angle ⁇ , which, for example, can be an acute angle up to approximately 15 degrees.
  • Other possible forms of eccentricities include a predefined curve or kink manufactured into the columns.
  • Fig. 4 illustrates an example of this.
  • an energy absorber 70 having an inner layer 72, and outer layer 74, and a plurality energy absorbing columns 76.
  • Some of the columns 78 comprise a medial kink 80 that facilitates buckling.
  • the energy absorbing columns 56 have been described as comprising cylindrical members, which typically comprise circular cross-sections, it is noted that other cross-sectional geometries are possible.
  • the columns 56 can have an elliptical, polygonal, or other non-uniform cross-section.
  • the columns 56 can have a twisted configuration in which the cross-section changes along the length of the columns. For example, if the column 56 had an elliptical cross-section, the orientation of the ellipse can rotate as the length of the column is traversed to form a twisted shape.
  • Such a shape can force the columns 56 to twist while buckling, which both increases the energy dissipation rate in the later stages of collapse and forces the top half of the column to land beside the bottom half, which reduces the stack-up distance and maximizes available compression in the energy absorber.
  • Each of the inner liner 52, outer liner 54, and the energy absorbing columns 56 can be made of an elastomeric material.
  • these components are made of a thermoplastic elastomer (TPE), such as thermoplastic polyurethane (TPU).
  • TPU thermoplastic polyurethane
  • BASF Elastollan 1260D U is one commercial example of a TPU.
  • TPEs include copolyamides (TPAs), copolyesters (TPCs), polyolefin elastomers (TPOs), and polystyrene thermoplastic elastomers (TPSs).
  • TPU may be preferable for construction of the energy absorbers for a variety of reasons.
  • This material can be made to be soft enough to provide consistent initiation of the buckling process, has a rapid relaxation time to assure high rates of energy dissipation, and has proven to be both durable and tolerant of large temperature variations.
  • Both the viscoelastic nature of TPU and the sensitivity of column buckling to impact speed enable the energy absorbing columns to absorb greater amounts of energy as impact speed increases. This is important for helmets that must attenuate high speed impacts and simultaneously provide optimum protection of helmet wearers who experience large numbers of low speed impacts.
  • TPU is a low cost, versatile, and commercially available material.
  • all grades of unreinforced TPU have high elasticity with elongation to break values of 300 to 1000%, tensile strength to yield of 10 to 45 MPa, hardness values of 52 to 98 on the Shore A scale and 22 to 95 on the Shore D scale, and material densities in the range of 1 .05 to 1 .53 g/cc.
  • TPU also has a low glass transition temperature of -69 to -17°C, meaning that it will retain its elastic properties over the a broad range of temperatures, such as that in which sports are played.
  • TPU provides excellent abrasion resistance, impact strength, weather resistance, and antimicrobial properties.
  • TPU can be modified to suit a particular application by adding fillers, colorants, or stabilizers.
  • One desirable performance characteristic is that TPU can be optimized to achieve effective damping with optimal rebound speed (e.g. short relaxation time).
  • TPU provides fabrication flexibility, can be injection molded, and can be bonded or welded though a variety of processes.
  • a texture can be added to the inner surfaces of the inner and outer layers as well as the outer surfaces of the columns.
  • Such a texture is schematically illustrated in Fig. 3 as texture 82 and can cause the columns to lock in place once contact is made with other columns and/or the inner and/or outer layers.
  • the texture 82 can comprise a rough surface that is formed on the layers/columns during energy absorber fabrication (e.g., injection molding).
  • this texture 82 can comprise a geometric (e.g., metal) mesh that is integrated into the surfaces during fabrication (e.g., injection molding).
  • the energy absorbers can be manufactured in two parts.
  • the first part can comprise the outer layer and all the necessary features for attaching the energy absorber to the outer shell 12, while the second part can comprise the inner layer and the columns that are connected thereto.
  • the two parts can be produced through injection molding or another commercial manufacturing process. Once formed, the two parts can be bonded together through use of welding or an adhesive.
  • the layers and columns could each be manufactured as separate parts. In such a case, the columns can comprise notches at their ends that enable them to be snapped into place into pre-formed holes in the inner and outer layers. The columns could then be bonded to the layers through welding or adhesion.
  • an energy absorber 90 comprises an inner layer 92, an outer layer 94, and a plurality of energy absorbing columns 96.
  • the outer layer 94 has been pushed in toward the inner layer 92 because of an external (downward) force and, as a result, the columns 96 of the energy absorber 90 have bent and/or buckled under this force, thereby dissipating energy.
  • Figs. 6A and 6B illustrate operation of the energy absorbers when incorporated into a protective helmet 100.
  • the helmet 100 includes an inner liner 102 comprising multiple pads 104 having energy absorbing columns 106.
  • Fig. 6A shows the helmet 100 prior to impact. In this state, the helmet 100 is centered on the wearer's head.
  • Fig. 6B shows the helmet 100 upon receiving a tangential impact from another helmet 1 10.
  • the energy absorbing columns 106 near the point of impact have deformed to absorb the energy of the impact.
  • the helmet 100 has rotated relative to the wearer's head to dissipate the rotational force imparted by the helmet 1 10 instead of delivering it directly to the wearer's head. In such a case, the wearer's head can remain relatively stationary, at least in terms of rotation, while the helmet 100 rotates. Once the force is removed, however, the energy absorbing columns 106 can return the helmet 100 to its original orientation on the head.
  • the energy absorbers can comprise other components besides columns between their inner and outer layers.
  • Fig. 7 illustrates an energy absorber 120 comprising an inner layer 122, an outer layer 124, and a plurality of energy absorbing columns 126.
  • the member 128 can comprise a foam element or an air bladder element that provides increased energy dissipation where needed, such as near the front of a helmet.
  • the member 128 is generally elliptical with its long axis extending along the normal directions of the inner and outer layers 122, 124.
  • the basic premise of impact energy management is to optimize energy absorption in each component of a system. So, while the inner liners described above can be used to absorb energy, other components of the helmet can likewise be designed to absorb energy. Once such component is the outer shell of the helmet.
  • the shell material in most commercial football helmets is made of polycarbonate (PC) alloys or acrylonitrile butadiene styrene (ABS) plastic in thicknesses ranging from 3 to 4 mm. While these materials have high impact resistance, they exhibit a highly elastic response to impacts. Therefore, the energy absorbed by the shell material is minimal. Greater energy could be absorbed, however, if the shell was made of a deformable, energy absorbing material.
  • PC polycarbonate
  • ABS acrylonitrile butadiene styrene
  • the outer shell 12 of the protective helmet 10 can be made of such a material.
  • the shell 12 is made of a polyethylene (PE) composition, such as high density polyethylene (HDPE).
  • PE polyethylene
  • HDPE high density polyethylene
  • HDPE is a class of thermoplastic polymers that incorporate long chains of polyethylene mers with molecular weights in the range of approximately 100,000 to 3,000,000.
  • HDPE is a suitable replacement for the elastic PC or ABS materials used in current football helmets, whether or not the helmets include an inner liner of the nature described above.
  • HDPE high-cost polyethylene
  • Specific parameters of a suitable HDPE composition include the following:
  • HDPE offers a lower density (0.95 g/cm 3 ) when compared to conventional PC (1 .2 g/cm 3 ) or ABS (1 .05 g/cm 3 ) formulations.
  • a lower density can be advantageous by providing lower weight to the wearer or a thicker geometry for the same weight.
  • the shell has a thickness of approximately 2.4 to 4 mm.
  • HDPE also offers a low glass transition temperature of -70°C to -80°C.
  • Such additives can include a processing stabilizer that protects the polymer at high temperatures, a heat stabilizer that inhibits degradation of the end product, a slip agent that reduces friction between surfaces (i.e., increases slip), and an ultraviolet stabilizer that inhibits environmental degradation.
  • ADDCOMP ADD-VANCE 148 and 796 are two example commercial multi-functional additives that could be used. A range of approximately 1 to 8% by weight of the additives can be compounded with the PE base in the composition.
  • Figs. 8A and 8B illustrate the effect of constructing the outer shell 12 of the protective helmet 10 out of an energy absorbing material, such as HDPE.
  • Fig. 8A shows the helmet 10 prior to impact.
  • Fig. 8B shows the helmet 10 upon receiving an impact to the top of the shell 12.
  • the shell 12 has locally deformed at the point of impact and thereby dissipates some of the impact force.
  • the energy absorbing columns 56 have also deformed near the point of impact.
  • Tethering a helmet involves attaching one or more flexible tethers between the wearer's helmet and an object securely anchored to the wearer's body. Such tethers greatly increase the helmet's resistance to motion by firmly securing the helmet to the wearer's upper body. If properly designed, tethers can reduce peak accelerations by as much as 80 percent by raising the effective mass of the head and helmet from approximately 13 lbs. to over 70 lbs.
  • An effective helmet tether system can incorporate the following features: A) enables the head/neck complex to freely rotate and posterior flex when not being struck; B) provides resistance to acceleration when helmet is struck; C) cannot apply excessive force to helmet; D) cannot obstruct players vision; and E) easily attaches and detaches from the helmet.
  • a helmet tether system can be designed as a passive or an active system. Passive tether systems are designed to resist extreme motions, such as excessive deflection or velocity. Active tether systems, however, incorporate sensors that sense when an impact has either begun or is about to occur and includes actuation mechanisms that actively respond to such sensed conditions.
  • Fig. 9 illustrates a first embodiment of a passive helmet tether system 140 that links a protective helmet 142 to an article 144 (shoulder pads in this example) worn by the helmet wearer.
  • the system 140 includes multiple tethers 146 that extend between the helmet 142 and the shoulder pads 144. More particularly, a first or upper end of each tether is attached to the interior or exterior of the outer shell 148 of the helmet 142, and a second or lower end of each tether is attached to the outer shells 150 of the shoulder pads 144. In the illustrated embodiment, the lower ends of the tethers 146 are attached to and wrapped around spools 152 that are fixedly mounted to the shoulder pad outer shells 150.
  • the spools 152 are free to rotate to enable lengthening of the tether 146 to enable turning of the head until the maximum length has been reached, at which point the tether limits further helmet movement.
  • the tether system 140 limits the forces that can be transmitted to the wearer's head.
  • the tethers 146 comprise high-strength, flexible, inelastic cords.
  • Example inelastic cord materials include steel, nylon, polypropylene, and polyethylene.
  • the spools 152 can comprise internal torsion springs (not shown) that take up any slack that forms in the tethers 146.
  • the spools 152 can further comprise internal locking mechanisms (not shown), such as centrifugal brakes, that automatically lock the angular orientations of the spools, and therefore halt lengthening of the tethers 146, upon a threshold angular acceleration being reached.
  • the threshold angular acceleration can be one that is associated with movements of the helmet 142 that exceed the speed with which the wearer can move his or own head, which are indicative of a helmet impact.
  • Fig. 10 illustrates a second embodiment of a passive helmet tether system 160 that links a protective helmet 162 to an article 164 (shoulder pads) worn by the helmet wearer.
  • the system 160 is similar to the system 140 in that a first or upper end of each tether 166 is attached to the outer shell 168 of the helmet 162, and a second or lower end of each tether is attached to the outer shells 170 of the shoulder pads 164.
  • this embodiment comprises no spools.
  • the tethers 146 comprise flexible, elastic cords that resist movement as they are stretched.
  • Example elastic cord materials include elastomers such as synthetic rubber, and TPU, and fiber-reinforced elastomers.
  • Fig. 1 1 illustrates a third embodiment of a passive helmet tether system 180 that links a protective helmet 182 to an article 184 (shoulder pads) worn by the helmet wearer.
  • This system 180 is also similar to the system 140 shown in Fig. 9. Accordingly, the system 180 comprises multiple tethers 186 having a first or upper end attached to the outer shell 188 of the helmet 182, and a second or lower end attached to the shoulder pad outer shells 190.
  • an extension mechanism 192 is provided along each tether 186. Lengths of the tethers 186 are wound around an internal spool (not shown) within the extension mechanism 192, which also includes an internal torsion spring (not shown) that takes up slack.
  • the extension mechanism 192 can further include a locking mechanism (not shown) that automatically locks the angular orientation of the internal spool, and therefore halts lengthening of the tether 186, upon a threshold angular acceleration being reached.
  • Fig. 12 illustrates a first embodiment of an active helmet tether system 200 that links a protective helmet 202 to an article 204 (shoulder pads) worn by the helmet wearer.
  • the system 200 includes multiple tethers 206 that extend between the helmet 202 and the shoulder pads 204. More particularly, a first or upper end of each tether is attached to the interior or exterior of the outer shell 208 of the helmet 202, and a second or lower end of each tether is attached to and wrapped around spools 210 that are releasably mounted to the shoulder pad outer shells 212.
  • the system 200 further comprises pre-tensioned springs 214 that are attached at one end to a spool 210 and attached at the other end to the shoulder pad outer shell 212.
  • the system 200 includes an impact sensor 216, such as an accelerometer, that is mounted to the helmet 202 or the wearer's head.
  • the impact sensor 216 is in communication with a central controller 218 that is adapted to actuate the spools 210.
  • the spools 210 are free to rotate to enable lengthening of the tether 206 to enable turning of the head until an impact that exceeds a force threshold is sensed by the sensor 216.
  • the central controller 218 activates actuation mechanisms (not shown) associated with each spool 210 that halt further rotation of the spools and decouple the spools from the shoulder pads 204.
  • actuation mechanisms not shown
  • the tethers 206 will no longer lengthen and the springs 214 will pull down on the spools 210 to remove slack from the tethers.
  • Fig. 13 illustrates a second embodiment of an active helmet tether system 220 that links a protective helmet 222 to an article 224 (shoulder pads) worn by the helmet wearer.
  • the system 220 includes multiple inelastic tethers 226 having a first or upper end attached to the outer shell 228 of the helmet 222, and a second or lower end attached to and wrapped around spools 230 that are fixedly mounted to the shoulder pad outer shells 232.
  • the system 220 further comprises multiple sensors 234, such as accelerometers, that are mounted at multiple points on the helmet wearer's body (multiple locations of the shoulder pads 224 in the example of Fig. 13).
  • the data collected by the sensors 234 can be provided to a central controller 236 that executes a control algorithm that determines from wearer's body posture and motion that a helmet impact is likely to occur.
  • the central controller 236 can activate pre-tensioning mechanisms (not shown) associated with each spool 232 that wind the tethers 226 onto the spools 230 to prepare the head for an impending impact.
  • the control algorithm comprises a heuristic algorithm that adapts to the individual helmet wearer over time.
  • the pre-tensioning mechanisms can comprise electro-active materials used to form the tethers 226, such as dielectric elastomers. Signaling of such electro-active tethers could be used to induce changes in stiffness and strain.

Landscapes

  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Physical Education & Sports Medicine (AREA)
  • Helmets And Other Head Coverings (AREA)

Abstract

La présente invention concerne, dans un mode de réalisation, un casque de protection qui comprend une coque extérieure et un revêtement intérieur placé à l'intérieur de la coque extérieure, le revêtement comprenant un absorbeur d'énergie qui comprend une première couche, une seconde couche opposée, et une pluralité de colonnes d'absorption d'énergie disposées entre les couches, les colonnes comprenant des colonnes relativement longues qui sont fixées à la fois à la première couche et à la seconde couche et des colonnes relativement courtes qui sont fixées uniquement à la première couche ou uniquement à la seconde couche.
PCT/US2015/060225 2014-11-11 2015-11-11 Casques de protection comportant des revêtements d'absorption d'énergie WO2016077501A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US15/526,045 US20170303623A1 (en) 2014-11-11 2015-11-11 Protective helmets having energy absorbing liners
CA2966656A CA2966656A1 (fr) 2014-11-11 2015-11-11 Casques de protection comportant des revetements d'absorption d'energie

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
US201462078007P 2014-11-11 2014-11-11
US62/078,007 2014-11-11
US201562100751P 2015-01-07 2015-01-07
US62/100,751 2015-01-07
US201562180666P 2015-06-17 2015-06-17
US62/180,666 2015-06-17

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US (1) US20170303623A1 (fr)
CA (1) CA2966656A1 (fr)
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018013996A3 (fr) * 2016-07-15 2018-02-22 VICIS, Inc. Système de revêtement modulaire pour casques de protection

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120017358A1 (en) * 2010-07-22 2012-01-26 Wingo-Princip Management LLC Protective helmet
US10716352B2 (en) * 2011-07-21 2020-07-21 Brainguard Technologies, Inc. Visual and audio indicator of shear impact force on protective gear
US20180055103A1 (en) * 2012-08-27 2018-03-01 Nick Trozzi Safe Air Head, Face, and Body Gear
US9615618B2 (en) * 2013-12-18 2017-04-11 Konstantinos Margetis System and method for head and spine immobilization and protection
US10477909B2 (en) 2013-12-19 2019-11-19 Bauer Hockey, Llc Helmet for impact protection
US9961952B2 (en) 2015-08-17 2018-05-08 Bauer Hockey, Llc Helmet for impact protection
WO2017120381A1 (fr) 2016-01-08 2017-07-13 University Of Washington Through Its Center For Commercialization Matériaux et structures en couches pour une meilleure absorption des chocs
US10660389B2 (en) * 2017-01-18 2020-05-26 Richard A. Brandt Energy dissipating helmet
US11019871B2 (en) * 2017-07-28 2021-06-01 Ali M. Sadegh Biomimetic and inflatable energy-absorbing helmet to reduce head injuries and concussions
WO2019152992A1 (fr) 2018-02-05 2019-08-08 VICIS, Inc. Protection de casque spécifique à la position
US20210315308A1 (en) * 2018-08-14 2021-10-14 Lazer Sport Nv Protective helmet
EP3903616B1 (fr) * 2018-10-16 2024-06-05 Lazer Sport NV Casque de protection contre les chocs
US11812811B2 (en) * 2018-11-23 2023-11-14 Michael Baker Energy diverting football helmet
US20200163398A1 (en) * 2018-11-23 2020-05-28 Michael Baker Energy diverting football helmet
US20240090610A1 (en) * 2018-11-23 2024-03-21 Michael Baker Energy divertiging football helmet
CA3133385A1 (fr) * 2019-03-14 2020-09-17 Socovar L.P. Casque avec conformation de rembourrage
AU2020279251B2 (en) * 2019-05-20 2023-12-07 Gentex Corporation Helmet impact attenuation liner
WO2022178482A1 (fr) * 2021-02-03 2022-08-25 Impact Technologies, Llc Revêtements de casque à dissipation d'impact avec tiges de retenue cylindriques

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3447163A (en) * 1966-02-16 1969-06-03 Peter W Bothwell Safety helmets
US8069498B2 (en) * 2009-06-02 2011-12-06 Kranos Ip Corporation Protective arrangement
US8387164B2 (en) * 2009-12-09 2013-03-05 Kranos Ip Corporation Plastic foam helmet pad
US20130185837A1 (en) * 2011-09-08 2013-07-25 Emerson Spalding Phipps Protective Helmet
US20140007322A1 (en) * 2010-10-06 2014-01-09 Cortex Armour Inc. Shock absorbing layer with independent elements
US20140208486A1 (en) * 2013-01-25 2014-07-31 Wesley W.O. Krueger Impact reduction helmet

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3877076A (en) * 1974-05-08 1975-04-15 Mine Safety Appliances Co Safety hat energy absorbing liner
GB0116738D0 (en) * 2001-07-09 2001-08-29 Phillips Helmets Ltd Protective headgear and protective armour and a method of modifying protective headgear and protective armour
WO2012109381A1 (fr) * 2011-02-09 2012-08-16 Innovation Dynamics LLC Systèmes de gestion d'énergie omnidirectionnelle de casque
US9486029B2 (en) * 2014-03-31 2016-11-08 Raytheon Company Solid-liquid energy dissipation system, and helmet using the same

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3447163A (en) * 1966-02-16 1969-06-03 Peter W Bothwell Safety helmets
US8069498B2 (en) * 2009-06-02 2011-12-06 Kranos Ip Corporation Protective arrangement
US8387164B2 (en) * 2009-12-09 2013-03-05 Kranos Ip Corporation Plastic foam helmet pad
US20140007322A1 (en) * 2010-10-06 2014-01-09 Cortex Armour Inc. Shock absorbing layer with independent elements
US20130185837A1 (en) * 2011-09-08 2013-07-25 Emerson Spalding Phipps Protective Helmet
US20140208486A1 (en) * 2013-01-25 2014-07-31 Wesley W.O. Krueger Impact reduction helmet

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018013996A3 (fr) * 2016-07-15 2018-02-22 VICIS, Inc. Système de revêtement modulaire pour casques de protection
US10342281B2 (en) 2016-07-15 2019-07-09 VICIS, Inc. Modular liner system for protective helmets

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US20170303623A1 (en) 2017-10-26

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