Head protection for reducing linear acceleration
Safety head wear for use for example in high risk activities such as sports and industrial purposes where protection from head injuries is required. Components are provided inserted between the liner and outer shell and consists of two parts; a pod and a foam or foam like surrogate or structure. The foam or foam like material is contained in the chamber and is positioned in such a way to create constant force between the surface of the shell and head. The device provides a method of managing compression force characteristics of the helmet around the head designed to decrease brain trauma resulting from high linear acceleration during impacts to the helmet.
1. Protective headwear for protection from a load generated by impact accelerations comprising:
an outer member for engaging external objects;
an inner layer having an inner surface and an outer surface;
a plurality of compressible components arranged between the outer member and the inner layer at spaced positions around the inner layer;
the compressible components being arranged to compress in a direction generally orthogonal to the inner layer so as to absorb said load;
each compressible component comprising:
a body having an inner surface for engaging the inner layer and an outer surface for engaging the outer member;
the body comprising a tubular peripheral wall having the compression characteristics such that the tubular peripheral wall is collapsible longitudinally when a load is applied between the inner and outer surfaces greater than a predetermined load;
and a compressible body located inside the tubular peripheral wall and having the compression characteristics to provide a resistance to compression;
such that each compressible component responds to said load by combining the characteristics of the peripheral wall and the resistance to compression of the compressible body.
2. The protective headwear according to claim 1 wherein the inner layer comprises a stiff inner liner and the outer member comprises an outer shell and wherein the components are arranged between the inner liner and the outer shell for absorbing the forces applied between the outer shell and the inner liner.
3. The protective headwear according to claim 1 wherein the outer member forms a part of the compressible components without an additional rigid shell so that the compressible components are directly engaged at the outer member by objects impacting the headwear.
4. The protective headwear according to claim 1 wherein the tubular peripheral wall is formed of a resilient material.
5. The protective headwear according to claim 1 wherein the tubular peripheral wall is formed of molded plastics material.
6. The protective headwear according to claim 1 wherein the compressible body is shaped to engage the tubular peripheral wall around its full periphery.
7. The protective headwear according to claim 1 wherein the tubular peripheral wall is sufficiently elastic to resume its initial shape after said load is removed.
8. The protective headwear according to claim 1 wherein the combined characteristics of the peripheral wall and the compressible body provide a force curve that absorbs energy at a constant rate throughout the duration of said load.
9. The headwear according to claim 1 wherein the combined characteristics of the peripheral wall and the compressible body provide a force curve that absorbs energy at a constant rate as the component is compressed.
10. The protective headwear according to claim 1 wherein the tubular peripheral wall is cylindrical and of constant thickness.
11. The protective headwear according to claim 1 wherein the tubular peripheral wall is frustoconical.
12. The protective headwear according to claim 1 wherein the tubular peripheral wall is of varying thickness along its height.
13. The protective headwear according to claim 1 wherein the compressible components are mounted in a flexible support which allows lateral movement of the compressible components relative to of the inner layer and the outer member to allow shearing movement of the inner layer relative to the outer member.
14. The protective headwear according to claim 13 wherein the flexible support comprises an elastic membrane which attached to the tubular peripheral wall.
15. Protective headwear for protection from a load generated by impact accelerations comprising:
an outer member for engaging external objects;
an inner layer having an inner surface and an outer surface;
a plurality of compressible components arranged between the outer member and the inner layer at spaced positions around the inner layer;
the compressible components being arranged to compress in a direction generally orthogonal to the inner layer so as to absorb said load;
the compressible components being separated each from the next by an open space free of intervening material so that the compressible components are free to compress independently of one another without resistance from material in the open space;
each compressible component comprising:
a body having an inner surface for engaging the inner layer and an outer surface for engaging the outer member;
the body comprising a single tubular peripheral wall having the compression characteristics such that the tubular peripheral wall is collapsible longitudinally when a load is applied between the inner and outer surfaces greater than a predetermined load, the tubular peripheral wall being unsealed to allow air escape during collapse so that resistance to collapse is provided by the tubular peripheral wall;
and a compressible body located inside the tubular peripheral wall and having the compression characteristics to provide a resistance to compression;
wherein the compressible body has a height less than that of the tubular peripheral wall so as to be spaced from one or both of the inner layer and outer member;
at least a part of the tubular peripheral wall being free from contact with the compressible body so as to be collapsible longitudinally without resistance from engagement with the compressible body;
such that each compressible component responds to said load by combining the characteristics of firstly the collapse of the peripheral wall and subsequently the resistance to compression of the compressible body.
16. The protective headwear according to claim 15 wherein the inner layer comprises a stiff inner liner and the outer member comprises an outer shell and wherein the components are arranged between the inner liner and the outer shell for absorbing the forces applied between the outer shell and the inner liner.
17. The protective headwear according to claim 15 wherein the outer member forms a part of the compressible components without an additional rigid shell so that the compressible components are directly engaged at the outer member by objects impacting the headwear.
18. The protective headwear according to claim 15 wherein the tubular peripheral wall is cylindrical and of constant thickness.
19. The protective headwear according to claim 15 wherein the tubular peripheral wall is frustoconical.
20. The protective headwear according to claim 15 wherein the tubular peripheral wall is of varying thickness along its height.
21. The protective headwear according to claim 15 wherein the compressible components are mounted in a flexible support which allows lateral movement of the compressible components relative to one or both of the inner layer and the outer member to allow shearing movement of the inner layer relative to the outer member.