Hard Hat with Impact Protection Material

Abstract

A hard hat and related impact protection layer is shown. The hard hat includes one or more feature to improve support of the impact protection layer. The impact protection layer is designed to improve impact energy absorption provided by a crushable material located within the hard hat shell.

What is claimed is: 
     
         1 . A hard hat, comprising:
 an outer shell comprising:
 an exterior surface; 
 an interior surface defining a cavity; 
 a crown portion positioned in a central area of the hard hat surrounding a center point; and 
 a bottom portion defining a lower circumference extending along the exterior surface; and 
   an impact protection layer positioned within the cavity, the impact protection layer comprising:
 a first piece supported at a first location within the cavity; and 
 a second piece supported at a second location within the cavity; 
   wherein the first piece and the second piece of the impact protection layer have a non-uniform stiffness such that each piece has a first compression axis having a first stiffness and a second compression axis having a second stiffness, and wherein the first stiffness is greater than the second stiffness.   
     
     
         2 . The hard hat of  claim 1 , wherein the first stiffness is at least twice the second stiffness. 
     
     
         3 . The hard hat of  claim 1 , wherein the first compression axis is aligned in a direction of a major axis of each piece of the impact absorbing layer, the major axis generally extending from the center point toward the bottom portion of the outer shell and the second compression axis is aligned in a direction of a minor axis of each piece of the impact absorbing layer, the minor axis generally extending in a circumferential direction around the cavity of the outer shell. 
     
     
         4 . The hard hat of  claim 3 , wherein the first and second pieces of the impact absorbing layer have a tapered shape such that a width extending in the direction of the minor axis increases along the major axis in a direction toward the bottom portion of the outer shell. 
     
     
         5 . The hard hat of  claim 1 , wherein the first piece and the second piece of the impact absorbing layer are positioned along the interior surface of the outer shell. 
     
     
         6 . The hard hat of  claim 1 , further comprising a retention ring coupled to the interior surface of the outer shell, wherein the retention ring retains the first piece and the second piece of the impact absorbing layer along the interior surface of the outer shell. 
     
     
         7 . The hard hat of  claim 6 , wherein the first piece and the second piece of the impact absorbing layer are flush with the interior surface of the outer shell. 
     
     
         8 . The hard hat of  claim 1 , wherein the first piece and the second piece of the impact absorbing layer are radially aligned sections extending outward from the crown portion of the outer shell toward the bottom portion. 
     
     
         9 . A hard hat, comprising:
 an outer shell comprising:
 an exterior surface; 
 an interior surface defining a cavity; 
 a crown portion positioned in a central area of the hard hat surrounding a center point; and 
 a brim portion defining a lower circumference extending along the exterior surface; 
   an impact protection layer positioned within the cavity, the impact protection layer comprising:
 a first piece supported at a first location within the cavity; and 
 a second piece supported at a second location within the cavity; 
   wherein the first piece and the second piece of the impact protection layer have a non-uniform stiffness such that each piece has a first compression axis having a first stiffness and a second compression axis having a second stiffness;   wherein the first stiffness is greater than the second stiffness and wherein the first compression axes of the first piece and the second piece are nonparallel to each other.   
     
     
         10 . The hard hat of  claim 9 , wherein the first stiffness is at least three times the second stiffness. 
     
     
         11 . The hard hat of  claim 9 , wherein the first compression axis is aligned in a direction extending generally from the center point toward the brim portion of the outer shell and the second compression axis is aligned in a direction extending in a circumferential direction around the cavity of the outer shell. 
     
     
         12 . The hard hat of  claim 9 , wherein the first piece and the second piece of the impact absorbing layer are positioned along the interior surface of the outer shell such that the first piece and the second piece are flush with the interior surface of the outer shell. 
     
     
         13 . The hard hat of  claim 9 , wherein the first piece and the second piece of the impact absorbing layer have a first thickness positioned at the crown of the outer shell and a second thickness positioned at the brim of the outer shell. 
     
     
         14 . The hard hat of  claim 13 , wherein the second thickness is less than the first thickness. 
     
     
         15 . A hard hat, comprising:
 an outer shell comprising:
 an exterior surface; 
 an interior surface defining a cavity; 
 a crown portion positioned in a central area of the hard hat surrounding a center point; and 
 a bottom portion defining a lower circumference extending along the exterior surface; and 
   an impact protection layer positioned within the cavity, the impact protection layer comprising:
 a plurality of sections, each section comprising:
 a first compression axis having a first stiffness; and 
 a second compression axis having a second stiffness, wherein the first stiffness is greater than the second stiffness; 
 
   wherein the plurality of sections are arranged such that an orientation of the first compression axis within each section is different from at least one adjacent section.   
     
     
         16 . The hard hat of  claim 15 , wherein the plurality of sections are radially aligned sections extending outward from the crown portion of the outer shell. 
     
     
         17 . The hard hat of  claim 15 , wherein the impact protection layer further comprises a central section positioned along the interior surface of the crown portion and the plurality of sections are radially aligned sections extending outward from the central section, the radially aligned sections including a curved inner edge. 
     
     
         18 . The hard hat of  claim 17 , wherein a circular crown perimeter defines a circumference along the exterior surface of the outer shell and the plurality of radially aligned sections of the impact protection layer have a variable thickness such that the plurality of radially aligned sections include a thicker portion at the crown perimeter adjacent the crown portion and decreasing thickness in a direction from the crown perimeter to a brim edge positioned at the bottom portion of the hard hat. 
     
     
         19 . The hard hat of  claim 15 , further comprising a retention rib coupled to the interior surface of the outer shell, wherein the retention rib retains the plurality of sections of the impact protection layer flush against the interior surface of the outer shell. 
     
     
         20 . The hard hat of  claim 15 , wherein the plurality of second of the impact absorbing layer each have a tapered shape such that a width extending in a direction of a minor axis increases along a major axis in a direction toward the bottom portion of the outer shell, wherein the minor axis extends in a circumferential direction around the cavity of the outer shell.