Impact Attenuating Tensile Helmet Liner

Abstract

A helmet liner for a helmet shell includes a peripheral wall configured to abut an inner surface of the helmet shell, and a bonnet configured to receive a head of a wearer. The bonnet is coupled to the peripheral wall and configured to be spaced from the inner surface of the helmet shell. The bonnet is configured to undergo tensile deformation in response to an impact event occurring at the helmet shell.

What is claimed is: 
     
         1 . A helmet liner for a helmet shell, the helmet liner comprising:
 a peripheral wall configured to abut an inner surface of the helmet shell; and   a bonnet configured to receive a head of a wearer and coupled to the peripheral wall and configured to be spaced from the inner surface of the helmet shell, the bonnet configured to undergo tensile deformation in response to an impact event occurring at the helmet shell.   
     
     
         2 . The helmet liner of  claim 1 , wherein the bonnet is a lattice structure defining a plurality of vents. 
     
     
         3 . The helmet liner of  claim 2 , wherein the lattice structure is a Voronoi tessellation 2D lattice structure. 
     
     
         4 . The helmet liner of  claim 2 , wherein the lattice structure is an auxetic lattice sheet structure. 
     
     
         5 . The helmet liner of  claim 1  further comprising:
 a plurality of impact attenuation pads coupled to an outer surface of the bonnet. 
 
     
     
         6 . The helmet liner of  claim 1  further comprising:
 one or more bellows protruding outwardly from an outer surface of the bonnet. 
 
     
     
         7 . The helmet liner of  claim 1 , wherein the helmet liner is custom fit to the contour of a wearer's head. 
     
     
         8 . The helmet liner of  claim 1 , wherein the helmet liner is comprised of one or more of: a rigid polyurethane, elastomeric polyurethane, a thermoset polymer, or a combination thereof. 
     
     
         9 . The helmet liner of  claim 1 , wherein the helmet liner is comprised of one or more of: polyamide, acrylonitrile butadiene styrene (ABS), polycarbonate, polyetherimide (PEI), and polyetherketone (PEEK). 
     
     
         10 . The helmet liner of  claim 1 , wherein the helmet liner is comprised of glass or carbon fiber reinforced composites. 
     
     
         11 . The helmet liner of  claim 1 , wherein the bonnet is comprised of a single layer of material. 
     
     
         12 . The helmet liner of  claim 1 , wherein the helmet liner weighs about 150 grams or less. 
     
     
         13 . The helmet liner of  claim 1 , wherein the helmet liner is comprised of a material having an elastic modulus of between about 0.75 GPa to about 100 GPa. 
     
     
         14 . A helmet for impact attenuation, the helmet comprising:
 a helmet shell including a material including ultra-high molecular weight polyethylene (UHMWPE), an inner surface, an outer surface, and a bottom peripheral edge; and   a helmet liner comprising:
 a peripheral wall abutting the inner surface of the helmet shell; and 
 a bonnet coupled to the peripheral wall and spaced from the inner surface of the helmet shell by an offset distance of between about 0.25 inches to about 2.0 inches. 
   
     
     
         15 . The helmet of  claim 14 , wherein the bonnet is a lattice structure defining a plurality of vents. 
     
     
         16 . The helmet of  claim 15 , wherein the lattice structure is a Voronoi tessellation 2D lattice structure. 
     
     
         17 . The helmet of  claim 15 , wherein the lattice structure is comprised of auxetic cells. 
     
     
         18 . The helmet of  claim 14 , wherein the bonnet is configured to undergo tensile deformation in response to an impact event occurring at the helmet shell. 
     
     
         19 . The helmet of  claim 14 , wherein the helmet liner further includes a plurality of impact attenuation pads coupled to an outer surface of the bonnet and positioned between the helmet liner and the helmet shell. 
     
     
         20 . The helmet of  claim 14 , wherein the helmet liner further includes one or more bellows protruding outwardly from an outer surface of the bonnet. 
     
     
         21 . A helmet liner for a helmet shell, the helmet liner comprising:
 a peripheral wall configured to abut an inner surface of the helmet shell; and   a tensile structure coupled to the peripheral wall and having a Voronoi tessellation 2D lattice structure pattern, the lattice structure comprised of a single layer of material and configured to be spaced from the inner surface of the helmet shell, the lattice structure configured to undergo tensile deformation in response to an impact event occurring at the helmet shell,   wherein the helmet liner weighs 150 grams or less.