Helmet

Abstract

A head protection helmet comprises an impact resistant shell comprising a cavity for accommodating a user's head and an array of crushable bodies having a hollow closed configuration, e.g. flutes in corrugated material. The crushable bodies each having an axis that extends outwardly from the cavity to absorb impact forces exerted along the direction of the axis.

1 . A head protection helmet comprising an impact resistant shell comprising:
 a cavity for accommodating a user's head and   an array of crushable bodies having a hollow closed configuration, the crushable bodies each having an axis that extends outwardly from the cavity to absorb impact forces exerted along the direction of the axis.   
     
     
         2 . A helmet as claimed in  claim 1 , wherein the crushable bodies are cells formed by intersecting arc-shaped ribs overlying the cavity, wherein the ribs extend outwards from the cavity. 
     
     
         3 . A helmet as claimed in  claim 2 , wherein the intersecting arc-shaped ribs are formed of crushable sheet material. 
     
     
         4 . A helmet as claimed in  claim 2 , wherein the crushable sheet material is a single sheet. 
     
     
         5 . A helmet as claimed in  claim 3 , wherein the ribs are each made of multiple sheets of a crushable board, the sheets of each rib being connected together. 
     
     
         6 . A helmet as claimed in  claim 5 , wherein the sheets of each rib are connected together by connector bodies that have an axis that lies generally orthogonal to the plane of the ribs. 
     
     
         7 . A helmet as claimed in  claim 5 , wherein the sheets of each rib are connected together by an array of honeycomb cells, the cells being of at least square, rectangular or hexagonal shape. 
     
     
         8 . A helmet as claimed in  claim 5 , wherein the sheets of each rib are connected together by at least one connector body having an axis and wherein said axis extends generally tangentially with respect to the cavity. 
     
     
         9 . A helmet as claimed in  claim 5 , wherein the sheets of each rib are connected together by crushable bodies having a hollow closed configuration, e.g. the crushable bodies each having an axis that extends outwardly from the cavity to absorb impact forces exerted along the direction of the axis. 
     
     
         10 . A helmet as claimed in  claim 1 , wherein the crushable bodies are flutes in corrugated material. 
     
     
         11 . A helmet as claimed in  claim 10 , wherein the corrugated material is in the form of arc-shaped ribs overlying the cavity, wherein the ribs extend outwards from the cavity. 
     
     
         12 . A helmet as claimed in  claim 11 , wherein the flutes in some of the ribs extend generally horizontally and the flutes in others of the ribs extend in a direction having at least a vertical component. 
     
     
         13 . A helmet as claimed in  claim 2 , wherein the array of ribs comprises ribs extending axially between the front and the back of the head cavity and ribs extending laterally between two opposed sides of the head cavity, the axial and lateral ribs intersecting, e.g. at crossed halved joints. 
     
     
         14 . A helmet as claimed in  claim 1 , wherein the shell includes a rim encircling the head cavity, the rim including said crushable bodies. 
     
     
         15 . A helmet as claimed in  claim 1 , wherein the crushable bodies are tubes that are arranged in an array, the tubes each having an axis that is directed outwardly away from the cavity. 
     
     
         16 . A helmet as claimed in  claim 15 , wherein the crushable bodies are frusto-cones with the larger surface facing outwards so that the axes of the frusto-cones extend outwardly from the cavity in different directions. 
     
     
         17 . A helmet as claimed in  claim 15 , wherein the tubes include a line of weakness in the walls of the tubes and are such that they crumple within their own diameters when impacted. 
     
     
         18 . A helmet as claimed in  claim 15 , wherein the tubes are formed by intersecting arc-shaped ribs overlying the cavity, wherein the ribs extend outwards from the cavity. 
     
     
         19 . A helmet as claimed in  claim 1 , wherein the crushable bodies have outwardly facing parts that are covered by a waterproof layer, which waterproofing layer is made of a material that has a stiffness coefficient higher than that of the material of the crushable bodies. 
     
     
         20 . A helmet as claimed in  claim 19 , wherein the waterproofing layer is an outer shell and optionally includes ventilation openings therein. 
     
     
         21 . A helmet as claimed in  claim 1 , which includes an inner shell which inner shell is in direct or indirect contact with the cavity of the impact absorbent shell and which is releasably connected thereto. 
     
     
         22 . A helmet as claimed in  claim 1 , which includes padding arranged to be next to the user's head and straps capable of extending under the chin of a user. 
     
     
         23 . An impact absorbent shell for a head protection helmet comprising:
 a cavity for accommodating a user's head and   an array of crushable bodies having a hollow closed configuration, the crushable bodies each having an axis that extends outwardly from the cavity to absorb impact forces exerted along the direction of the axis, the shell comprising:   a cavity for accommodating a user's head and an array of crushable bodies having a hollow closed configuration, the crushable bodies each having an axis that extends outwardly from the cavity to absorb impact forces exerted along the direction of the axis;   wherein the crushable bodies are cells formed by intersecting arc-shaped ribs overlying the cavity, wherein the ribs extend outwards from the cavity.   
     
     
         24 . A head protecting helmet comprising a shock indicator, that gives an indication when the helmet has been subject to a shock in excess of a threshold value, thereby indicating that the helmet or at least a shock absorbing part of the helmet should be replaced, which indicator comprises a chamber and at least 5 flasks spaced around the chamber, each flask having a space containing a colored liquid and each flask including a capillary bore that provides communication between the space of that flask and the chamber, wherein each capillary bore is capable of allowing the liquid in the space adjacent to it to pass into the chamber when the respective flask is subjected to a shock of at least said threshold value.