Layered construction of protective headgear with one or more compressible layers of thermoplastic elastomer material

Abstract

Protective headgear is described having an energy-absorbing shell attached to a compressible internal liner. The shell includes an outer shell layer, a non-compressible inner shell layer, and a compressible middle layer disposed between the outer shell layer and the non-compressible inner shell layer. The compressible middle layer is made of a thermoplastic elastomer material that can compress upon impact and return substantially to an original shape of the headgear after the impact has ended. Embodiments of the thermoplastic elastomer material have low rebound resilience, a low glass transition temperature, a honeycombed structure, or combinations thereof. The compressible internal liner can also be made of thermoplastic elastomer material.

1 . Protective headgear, comprising an impact-absorbing shell including a hard inner shell layer formed into a shape of helmet and a compressible layer attached to and covering an outer surface of the hard inner shell layer, the compressible layer being made of a thermoplastic elastomer material that compresses when impacted by a force and returns substantially to the original shape of the helmet after the force ceases.  
   
   
       2 . The protective headgear of  claim 1 , wherein the thermoplastic elastomer material has a honeycomb structure.  
   
   
       3 . The protective headgear of  claim 1 , wherein the thermoplastic elastomer has a glass-transition temperature below or equal to 0 degrees Fahrenheit.  
   
   
       4 . The protective headgear of  claim 1 , wherein the thermoplastic elastomer material has low rebound resilience.  
   
   
       5 . The protective headgear of  claim 1 , further comprising a compressible internal liner attached to an inner surface of the impact-absorbing shell, the internal liner making contact with the head of a wearer.  
   
   
       6 . The protective headgear of  claim 5 , wherein the internal liner is made of a thermoplastic elastomer material.  
   
   
       7 . The protective headgear of  claim 5 , wherein the internal liner is made of an expanded polystyrene foam.  
   
   
       8 . The protective headgear of  claim 1 , wherein the impact-absorbing shell further comprises an outer shell layer disposed on an outer surface of the compressible layer.  
   
   
       9 . Protective headgear, comprising: 
 an energy-absorbing shell including: 
 an outer shell layer;  
 a non-compressible inner shell layer; and  
 a compressible middle layer disposed between the outer shell layer and the non-compressible inner shell layer, the compressible middle layer being comprised of a thermoplastic elastomer material that can compress upon impact and return substantially to an original shape of the headgear after the impact has ended; and  
   a compressible internal liner attached to an inner surface of the energy-absorbing shell.    
   
   
       10 . The protective headgear of  claim 9 , wherein the thermoplastic elastomer material has a honeycomb structure.  
   
   
       11 . The protective headgear of  claim 9 , wherein the thermoplastic elastomer material of the middle layer has a glass-transition temperature below or equal to 0 degrees Fahrenheit.  
   
   
       12 . The protective headgear of  claim 9 , wherein the thermoplastic elastomer material of the middle layer and of the internal liner has low rebound resilience.  
   
   
       13 . The protective headgear of  claim 9 , wherein the internal liner is made of thermoplastic elastomer material.  
   
   
       14 . The protective headgear of  claim 9 , wherein the internal liner is made of expanded polystyrene foam.  
   
   
       15 . A method for making a helmet, comprising 
 providing a hard inner shell layer formed in a shape of a helmet; and    covering an outer surface of the hard inner shell layer with a compressible middle layer of thermoplastic elastomer material; and    covering an outer surface of the compressible middle layer with an outer shell layer.    
   
   
       16 . The method of  claim 15 , wherein the thermoplastic elastomer material has a honeycomb structure.  
   
   
       17 . The method of  claim 15 , wherein the thermoplastic elastomer material of the compressible middle layer has a glass-transition temperature below or equal to 0 degrees Fahrenheit.  
   
   
       18 . The method of  claim 15 , wherein the thermoplastic elastomer material of the compressible middle layer and of the internal liner has low rebound resilience.  
   
   
       19 . The method of  claim 15 , further comprising attaching a compressible internal liner made of thermoplastic elastomer material to an inner surface of the hard inner shell layer.  
   
   
       20 . The method of  claim 15 , further comprising attaching a compressible internal liner made of expanded polystyrene foam to an inner surface of the hard inner shell layer.