Energy absorbing sports helmet

Abstract

Slow recovery viscoelastic polyurethane foam with a surface impregnation of silicone, coupled with a rigid helmet shell, is used for athletic headgear. The helmet shell should have a rigid construct to provide dispersion of impact energy, absorbing at least thirty percent of the impact energy delivered to the helmet shell. The slow recovery viscoelastic polyurethane foam has unique characteristics making it suitable for use as an energy absorbing liner for athletic headgear. The energy absorbing liner can be made with varying thickness and size, so retail establishments can custom fit a helmet to a particular customer.

1 . A helmet for cushioning a head during a sudden impact, comprising: 
 a helmet shell; and    an energy absorbing protective liner fitted to an interior surface of the helmet shell, wherein the energy absorbing protective liner comprises a slow recovery viscoelastic material with surface impregnation of a waterproofing material.    
   
   
       2 . The helmet according to  claim 1 , wherein the slow recovery viscoelastic material is slow recovery viscoelastic polyurethane foam.  
   
   
       3 . The helmet according to  claim 1 , wherein the waterproofing material is silicone.  
   
   
       4 . A helmet for cushioning a head during a sudden impact, comprising: 
 a helmet shell; and    a plurality of energy absorbing protective pads ranged on an interior surface of the helmet shell, wherein each of the energy absorbing protective pads comprises a slow recovery viscoelastic material with surface impregnation of a waterproofing material.    
   
   
       5 . The helmet according to  claim 4 , wherein the slow recovery viscoelastic material is slow recovery viscoelastic polyurethane foam.  
   
   
       6 . The helmet according to  claim 4 , wherein the waterproofing material is silicone.  
   
   
       7 . The helmet according to  claim 4 , wherein the plurality of energy absorbing protective pads are shaped into pads of variable thickness and size.  
   
   
       8 . A helmet for cushioning a head during a sudden impact, comprising: 
 a helmet shell comprising a thermoplastic shell having a humanoid head shape, and lateral members at least partially disposed around a circumference of the thermoplastic shell; and    an energy absorbing protective liner fitted to an interior surface of the helmet shell, wherein the energy absorbing protective liner comprises a slow recovery viscoelastic material with surface impregnation of a waterproofing material.    
   
   
       9 . The helmet according to  claim 8 , wherein the helmet shell has a thickness of at least 2 millimeters.  
   
   
       10 . The helmet according to  claim 8 , wherein the thermoplastic shell is an injection molded plastic shell.  
   
   
       11 . The helmet according to  claim 8 , wherein the thermoplastic shell is a pressure molded thermoset resin reinforced with at least one of a glass fiber, KELVAR fiber or carbon fiber.  
   
   
       12 . The helmet according to  claim 8 , wherein the lateral members are thicker than other portions of the helmet shell.  
   
   
       13 . the helmet according to  claim 8 , wherein the lateral members disperse an impact force from a point of contact to other portions of the helmet shell.  
   
   
       14 . The helmet according to  claim 8 , wherein the helmet shell dispenses at least thirty percent of an impact force applied to the helmet shell.  
   
   
       15 . The helmet according to  claim 8 , wherein the slow recovery viscoelastic material is slow recovery viscoelastic polyurethane foam.  
   
   
       16 . The helmet according to  claim 8 , wherein the waterproofing material is silicone.  
   
   
       17 . The helmet according to  claim 8 , wherein each of the lateral members disposed around a circumference of the helmet shell is comprised of an upper lateral member and a lower lateral member, and the upper lateral member and the lower lateral member are separated by a lateral channel.  
   
   
       18 . The helmet according to  claim 17 , wherein the helmet shell further comprises a strap attachment member, and the lower lateral member is angled towards the location where the strap attachment member is disposed on the helmet shell.  
   
   
       19 . A helmet for cushioning a head during a sudden impact, comprising: 
 a helmet shell comprising a thermoplastic shell having a humanoid head shape, and lateral members disposed around a circumference of the thermoplastic shell; and    a plurality of energy absorbing protective pads arranged on an interior surface of the helmet shell, wherein each of the energy absorbing protective pads comprises a slow recovery viscoelastic material with surface impregnation of a waterproofing material.    
   
   
       20 . The helmet according to  claim 19 , wherein the slow recovery viscoelastic material is slow recovery viscoelastic polyurethane foam.  
   
   
       21 . The helmet according to  claim 19 , wherein the waterproofing material is silicone.  
   
   
       22 . The helmet according to  claim 19 , wherein the plurality of energy absorbing protective pads are shaped into pads of variable thickness and size.