Cellular energy-absorbing structure fastening device
Helmet ( 1 ) comprising: a shell ( 2 ); a head receiving system ( 3 ); at least one cellular energy-absorbing structure ( 4 ) comprising a plurality of interconnected open-cells ( 9 ) configured to absorb energy by deforming during an impact on the shell ( 2 ); at least one clamping device ( 5 ) comprising a base ( 6 ) and a counter-base ( 7 ) connected to each other via a collapsible body ( 8 ) sized so as to enter one or more open-cells ( 9 ) of the cellular energy-absorbing structure ( 4 ); wherein the base ( 6 ) or the counter-base ( 7 ) of the clamping device ( 5 ) comprises a low friction part ( 26 ) configured to enable a relative movement of the cellular energy-absorbing structure ( 4 ) and the clamping device ( 5 ) with respect to the shell ( 2 ).
1 . A helmet comprising:
a shell;
a head receiving system;
at least one cellular energy-absorbing structure comprising a plurality of interconnected open-cells configured to absorb energy by deforming during an impact on the shell;
at least one clamping device comprising a base and a counter-base connected to each other via a collapsible body, the collapsible body passes through one or more open-cells of the cellular energy-absorbing structure, and the base and the counter-base are opposite to each other with respect to the cellular energy-absorbing structure to connect the clamping device to the cellular energy-absorbing structure;
wherein the base or the counter-base of the clamping device comprises a low friction part, the low friction part is arranged over an outer surface of the base or counter-base facing the shell to enable the base or counter-base to slide over the shell, allowing a relative movement of the cellular energy-absorbing structure, together with the clamping device with respect to the shell.
2 . The helmet according to claim 1 , wherein the at least one cellular energy-absorbing structure comprises an array of energy-absorbing open-cells interconnected via their sidewalls.
3 . The helmet according to claim 2 , wherein each open-cell has an open base facing towards the shell and an opposite open base facing towards the head receiving system.
4 . The helmet according to claim 1 , wherein the at least one cellular energy-absorbing structure is a lattice structure comprising solid portions and open portions configured to form a network of interconnected open-cells.
5 . The helmet according to claim 4 , wherein the at least one cellular energy-absorbing structure is arranged so that one side of the structure faces towards the shell and an opposite side faces towards the head receiving system.
6 . The helmet according to claim 1 , wherein the at least one clamping device is configured so that the compressive force required to collapse the at least one clamping device along a direction is lower than or equal to that required to deform the open-cells of the at least one cellular energy-absorbing structure along the same direction.
7 . The helmet according to claim 1 , wherein the shell comprises only an outer hard shell and the low friction part is a spacer arranged between the at least one cellular energy-absorbing structure and the hard shell.
8 . The helmet according to claim 1 , wherein the shell comprises a rigid or semi-rigid outer shell and an inner shock absorbing liner connected to each other.
9 . The helmet according to claim 8 , wherein the inner shock absorbing liner comprises at least a pocket configured to retain and confine the cellular energy-absorbing structure.
10 . The helmet according to claim 8 , wherein the inner shock absorbing liner is made of a polymeric foam.
11 . The helmet according to claim 1 , wherein the head receiving system comprises a harness system or a comfort system.
12 . The helmet according to claim 1 , wherein the base or counter-base that does not comprise the low friction part is connected to the head receiving system through connecting means.
13 . The helmet according to claim 12 , wherein the connecting means comprise hook and look parts, an adhesive layer or snap-fit connector/s.
14 . The helmet according to claim 1 , wherein collapsible body is stretchable and is configured to appreciably and reversibly elongate with respect to its original length.
15 . The helmet according to claim 1 , wherein the collapsible body of the at least one clamping device is connected to the base and has an outer surface comprising a plurality of spaced teeth and spaced recesses, said counter-base comprises at least one flexible pawl shaped so to fit in one of said recesses, preferably the collapsible body is at least partially pleated or coiled, or comprises geometric perturbations to facilitate the collapse of the collapsible body.
16 . The helmet according to claim 15 , wherein the collapsible body is at least partially pleated or coiled, or comprises geometric perturbations to facilitate the collapse of the collapsible body.
17 . The helmet according to claim 1 , wherein the base comprises a protuberance having a dentition configured to cooperate with a mouth of a hollow body connected to the counter-base, said protuberance and said hollow body forming the collapsible body of the at least one clamping device.
18 . The helmet according to claim 1 , wherein the counter-base is configured to frictionally engage an inner sidewall of the at least one open-cell through a plurality of spaced flexible gripper elements protruding from the collapsible elongated body.
19 . The helmet according to claim 1 , wherein the shell comprises only an outer hard shell.
20 . The helmet according to claim 1 , wherein the shell comprises a rigid/semi-rigid outer shell and an inner shock absorbing liner connected to the rigid/semi-rigid outer shell.
21 . The helmet according to claim 20 , wherein the inner shock absorbing liner comprises at least a pocket configured to retain and confine the at least one cellular energy-absorbing structure and the at least one clamping device.