Football helmet

Abstract

A football helmet includes an outer shell configured to at least partially surround a head of a wearer. An inner liner is located substantially within the outer shell and is configured to contact at least a portion of the head of the wearer. A facial and mandibular protector is attached to the outer shell and is configured to at least partially surround a face of the wearer. The helmet has a center of gravity which, when the helmet is being worn, is substantially the same in two-dimensional location as the ventral-dorsal plane of the head of the wearer.

Having described the invention, we claim: 
     
         1 . A football helmet, comprising:
 an outer shell configured to at least partially surround a head of a wearer;   an inner liner, located substantially within the outer shell and configured to contact at least a portion of the head of the wearer; and   a facial and mandibular protector attached to the outer shell and configured to at least partially surround a face of the wearer;   wherein the helmet has a center of gravity which, when the helmet is being worn, is substantially the same in two-dimensional location to the ventral-dorsal plane of the head of the wearer.   
     
     
         2 . The football helmet of  claim 1 , wherein, when the helmet is being worn, the inner liner remains relatively stationary with respect to the wearer's head and relative motion is permitted between the inner liner and the outer shell when force is exerted upon the head of the wearer. 
     
     
         3 . The football helmet of  claim 1 , comprising a helmet moment of inertia which is chosen to reduce a risk of injury to the wearer when force is exerted upon the head of the wearer. 
     
     
         4 . The football helmet of  claim 1 , wherein an age category of the wearer is considered during design of the helmet and at least one dimension of the helmet is adjusted during design to provide at least one predetermined protective property for a wearer in that age category. 
     
     
         5 . The football helmet of  claim 4 , wherein the weight of a helmet worn by a wearer 10.9 years old or younger is in the range of 0.86 to 1.22 kilograms. 
     
     
         6 . The football helmet of  claim 5 , wherein the weight of a helmet worn by a wearer 9 years old is in the range of 1.00 to 1.22 kilograms. 
     
     
         7 . The football helmet of  claim 1 , wherein the helmet has a center of gravity which, when the helmet is being worn, is substantially the same in three-dimensional location as the center of gravity of the head of the wearer. 
     
     
         8 . The football helmet of  claim 1 , wherein the helmet has a center of gravity which, when the helmet is being worn, is caudal to the center of gravity of the head of the wearer. 
     
     
         9 . A football helmet, comprising:
 an outer shell configured to at least partially surround a head of a wearer;   an inner liner, located substantially within the outer shell and configured to contact at least a portion of the head of the wearer; and   a facial and mandibular protector attached to the outer shell and configured to at least partially surround a face of the wearer;   wherein the helmet has a helmet moment of inertia which is chosen to reduce a risk of injury to the wearer when force is exerted upon the head of the wearer.   
     
     
         10 . The football helmet of  claim 9 , wherein, when the helmet is being worn, the inner liner remains relatively stationary with respect to the wearer's head and relative motion is permitted between the inner liner and the outer shell when force is exerted upon the head of the wearer. 
     
     
         11 . The football helmet of  claim 9 , comprising a center of gravity which, when the helmet is being worn, is substantially the same in two-dimensional location as the ventral-dorsal plane of the head of the wearer. 
     
     
         12 . The football helmet of  claim 11 , wherein the helmet has a center of gravity which, when the helmet is being worn, is substantially the same in three-dimensional location as the center of gravity of the head of the wearer. 
     
     
         13 . The football helmet of  claim 11 , wherein the helmet has a center of gravity which, when the helmet is being worn, is caudal to the center of gravity of the head of the wearer. 
     
     
         14 . The football helmet of  claim 9 , wherein an age category of the wearer is considered during design of the helmet and at least one dimension of the helmet is adjusted during design to provide at least one predetermined protective property for a wearer in that age category. 
     
     
         15 . The football helmet of  claim 14 , wherein the weight of a helmet worn by a wearer 10.9 years old or younger is in the range of 0.86 to 1.22 kilograms. 
     
     
         16 . The football helmet of  claim 14 , wherein the weight of a helmet worn by a wearer 9 years old is in the range of 1.00 to 1.22 kilograms. 
     
     
         17 . A method of protecting at least one body structure of a wearer during athletic competition, the method comprising the steps of:
 providing a football helmet, comprising   an outer shell configured to at least partially surround a head of a wearer,   an inner liner, located substantially within the outer shell and configured to contact at least a portion of the head of the wearer, and   a facial and mandibular protector attached to the outer shell and configured to at least partially surround a face of the wearer;   configuring a center of gravity of the helmet to be substantially the same in two-dimensional location as the ventral-dorsal plane of the head of the wearer when the helmet is being worn.   
     
     
         18 . The method of  claim 17 , including the steps of:
 exerting a force upon the head of the wearer when the helmet is being worn;   maintaining the inner liner relatively stationary with respect to the wearer's head when the force is exerted upon the head of the wearer; and   permitting relative motion between the inner liner and the outer shell when force is exerted upon the head of the wearer.   
     
     
         19 . The method of  claim 17 , including the step of choosing a helmet moment of inertia to reduce a risk of injury to the wearer when force is exerted upon the head of the wearer. 
     
     
         20 . The method of  claim 17 , including the steps of:
 considering an age category of the wearer during design of the helmet; and   adjusting at least one dimension of the helmet during design to provide at least one predetermined protective property for a wearer in the considered age category.   
     
     
         21 . The method of  claim 20 , wherein the weight of a helmet worn by a wearer 10.9 years old or younger is in the range of 0.86 to 1.22 kilograms. 
     
     
         22 . The method of  claim 20 , wherein the weight of a helmet worn by a wearer 9 years old is in the range of 1.00 to 1.22 kilograms. 
     
     
         23 . The method of  claim 17 , wherein the step of configuring a center of gravity of the helmet includes the step of configuring a center of gravity of the helmet to be substantially the same in three-dimensional location as the center of gravity of the head of the wearer when the helmet is being worn. 
     
     
         24 . The method of  claim 17 , wherein the step of configuring a center of gravity of the helmet includes the step of configuring a center of gravity of the helmet to be caudal to the center of gravity of the head of the wearer when the helmet is being worn.