Elastic shear protection in protective gear

Abstract

Protective gear such as a helmet includes multiple shell layers connected using one or more shear protection devices. The shear protection devices have a general V-shaped configuration with one vertex point and two endpoints. Elastic bands connect the vertex with each endpoint. The vertex is secured to the inner surface of the outer shell layer and the two endpoints are attached to the outer surface of a middle shell layer. The devices flex downward or contracts when there is an impact on the helmet, such as a direct, rotational, or shear force. The device is able to absorb energy from the impact by flexing and allowing movement of the outer shell layer relative to the middle shell layer.

1 . A helmet, comprising:
 an outer shell layer;   a middle shell layer;   an inner shell layer; and   a first shear protection device having a vertex, a first endpoint, and a second endpoint connecting the outer shell and the middle shell layer, wherein the first shear device allows the outer shell layer to move relative to the middle shell layer when mechanical forces are imparted onto the outer shell layer.   
     
     
         2 . A helmet as recited in  claim 1 , wherein the device has a first elastic band between the vertex and the first end point and a second elastic band between the vertex and the second end point. 
     
     
         3 . A helmet as recited in  claim 1 , wherein the vertex is secured to an inner surface of the outer shell and the first end point and the second end point are secured to an outer surface of the middle shell. 
     
     
         4 . A helmet as recited in  claim 1  wherein the first shear protection device is in an energy and impact layer between the outer shell and the middle shell. 
     
     
         5 . A helmet as recited in  claim 4  wherein the protection device functions in conjunction with one or more of a fluid, gel, foam, liquid, ball bearing mechanism, conical structure, or concertinaed structure. 
     
     
         6 . A helmet as recited in  claim 2 , wherein the first shear protection device forms a V-shaped structure wherein the first elastic band has a first length and the second elastic band has a second length. 
     
     
         7 . A helmet as recited in  claim 1 , wherein the helmet contains multiple shear protection devices and depends on the surface are of the outer shell. 
     
     
         8 . A helmet as recited in  claim 1 , wherein the mechanical forces include shear forces and rotational forces. 
     
     
         9 . The helmet of  claim 1 , further comprising a second shear protection device connecting the middle shell layer to the inner shell layer, wherein the second device allows the middle shell layer to move relative to the inner shell layer. 
     
     
         10 . A helmet as recited in  claim 6  wherein the first length is the same as the second length or the first length is different from the second length. 
     
     
         11 . A helmet as recited in  claim 1  wherein the first elastic band and the second elastic band have a fixed tension. 
     
     
         12 . A helmet as recited in  claim 1  wherein the first end point and the second end point are secured to an inner surface of the outer shell layer and the vertex is secured to an outer surface of the middle shell. 
     
     
         13 . A helmet as recited in  claim 1  wherein the vertex has a first aperture and the first end point and second end point have a second aperture.