Shockwaves Attenuating Protective Headgear

Abstract

The present invention provides a protective headgear having a multi-layered configuration to attenuate amplitude of shock waves to a human head by inducing a first destructive interference of incident shock waves through phase reversal at a boundary between two adjacent layers of an outer shell, and a second destructive interference of transmitted shock waves across an inner layer in a cut-pile configuration. Shock waves is attenuated further by reflectively diffusing the transmitted shock waves at the boundary between the two adjacent layers of the outer shell, by reducing focused constructive interference between two symmetrically opposite transmitted shock waves coming centripetally off through the outer shell of the protective headgear, and by limiting seepage of the shock waves into an inner space between the protective headgear and the human head through filtrative trapping of the shock waves across the inner liner in the cut-pile configuration.

What is claimed is: 
     
         1 . A shock-waves attenuating protective headgear, comprising:
 an at-least three-layer outer shell comprising an outermost layer, a second layer, and a third layer, and an inner liner;   wherein the outermost layer of the at-least three-layer outer shell is configured to have a Rockwell hardness score of between 50 and 100, and wherein the outermost layer is fixedly attached to an outer surface of the second layer;   wherein the second layer of the at-least three-layer outer shell is provided in a configuration of hemispherical polyhedron comprising a plurality of flat polygons, wherein the second layer comprises a linear protruding ridge between two adjacent flat polygons arising from the outer surface of the second layer, wherein a first flat polygon of the second layer is axi-asymmetrically located opposite to a second flat polygon across an axial center of the hemispherical polyhedron of the second layer, and wherein the second layer is configured to have a Rockwell hardness score above 100;   wherein the third layer of the at-least three-layer outer shell comprises a polymeric base layer in a configuration of hemispheric bowel, wherein the third layer comprises a plurality of stiff polymeric cut piles radially projecting from the polymeric base layer toward an inner surface of the second layer, wherein the plurality of the stiff polymeric cut piles cover an entire outer surface of the third layer, wherein the third layer is encased by the second layer, and wherein the third layer is configured to have a hardness of a Shore D scale value of between 65 and 90; and   wherein the inner liner comprises a hemispherical polymeric base layer and a plurality of soft polymeric cut piles disposed around an inner circumferential rim portion of the inner liner, wherein the soft polymeric cut piles project from an inner surface of the hemispherical polymeric base layer of the inner liner to a hemispherical center of the hemispherical polymeric base layer in a way the soft polymeric cut piles is configured to fill in a circumferential space between a lower circumferential portion of the human head and the inner surface of the inner liner, and wherein the inner liner is releasably inserted in the third layer.   
     
     
         2 . The shock-waves attenuating protective headgear according to  claim 1 , further comprising:
 wherein the outermost layer and the second layer are configured to be resistant to compression and depressive deformation by an impact of a blunt trauma at an angle to a planar surface of the outermost layer and the second layer.   
     
     
         3 . The shock-waves attenuating protective headgear according to  claim 1 , further comprising:
 wherein the inner surface of the second layer is configured with a plurality of the flat polygons without a linear protruding ridge between two adjacent flat polygons; and   wherein a triangular apical point established by three adjacent polygons on the inner surface of the second layer is reinforced by a triangular planar buttress block made of the same materials as for the second layer.   
     
     
         4 . The shock-waves attenuating protective headgear according to  claim 1 , further comprising:
 wherein the third layer comprising the stiff polymeric cut piles is configured to be compressible and depressibly deformable by an impact of a blunt trauma at an angle to a planar surface of the third layer.   
     
     
         5 . The shock-waves attenuating protective headgear according to  claim 1 , further comprising;
 wherein the soft polymeric cut piles of the inner liner are provided in a configuration having a gap between adjacent soft polymeric cut piles for ventilation; and   wherein a first group of gaps between the adjacent soft polymeric cut piles of a first circumferential row of the soft polymeric cult piles are configured to be radially out of line with a second group of gaps between the adjacent soft polymeric cut piles of a second circumferential row of the soft polymeric cult piles, wherein the first group of the gaps are circumferentially disposed next to the second group of the gaps, and wherein arrangement of the first group of the gaps out of line with the second group of the gaps is configured to limit seepage of shock waves across the first group and the second group of the gaps.