Cellular energy-absorbing structure fastening device

Abstract

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 abase ( 6 ) and a counter-base ( 7 ) connected to each other by means of a stretchable elongated body ( 8 ) to forma a single piece sized so as to pass through at least one open-cell ( 9 ) of the cellular energy-absorbing structure ( 4 ), wherein the stretchable elongated body ( 8 ) is configured to appreciably and reversibly elongate with respect to its original length if pulled.

1 . 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 stretchable elongated body to form a single piece sized so as to pass through at least one open-cell of the cellular energy-absorbing structure; wherein the stretchable elongated body is configured to appreciably and reversibly elongate with respect to its original length if pulled.   
     
     
         2 . Helmet according to  claim 1 , wherein the stretchable elongated body is configured to reach a maximum elongation comprised between 150% and 500% of its original length. 
     
     
         3 . Helmet according to  claim 1 , wherein the stretchable elongated body is least in part made of an elastic or viscoelastic material. 
     
     
         4 . Helmet according to  claim 1 , wherein the cellular energy-absorbing structure comprises an array of energy-absorbing open-cells interconnected via their sidewalls. 
     
     
         5 . Helmet according to  claim 1 , wherein the cellular energy-absorbing structure is a lattice structure comprising solid portions and open portions configured to form a network of interconnected open-cells. 
     
     
         6 . Helmet according to  claim 1 , the clamping device is configured so that the compressive force required to collapse the clamping device along a direction is lower than or equal to that required to deform the open-cells of the cellular energy-absorbing structure along the same direction. 
     
     
         7 . Helmet according to  claim 1 , wherein the shell comprises only an outer hard shell. 
     
     
         8 . 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 . Helmet according to  claim 8 , wherein the inner shock absorbing liner comprises a pocket configured to retain the cellular energy-absorbing structure. 
     
     
         10 . Helmet according to  claim 1 , wherein the head receiving system comprises a harness system or a comfort system. 
     
     
         11 . Helmet according to  claim 1 , wherein the base or counter-base is connected to the shell or to the head receiving system through connecting means. 
     
     
         12 . Helmet according to  claim 11 , wherein the connecting means comprise a Velcro connection, an adhesive layer or snap-fit connector/s. 
     
     
         13 . Helmet according to  claim 1 , wherein the stretchable elongated body is inserted in a hole of the shell and the base or counter-base abuts against the shell. 
     
     
         14 . Helmet according to  claim 1 , comprising a low friction layer arranged on the base or counter-base of the at least one clamping device. 
     
     
         15 . Helmet according to  claim 1 , wherein the clamping device comprises an exceeding portion connected to the counter-base for pulling the stretchable elongated body through the at least one open-cell. 
     
     
         16 . Helmet according to  claim 1 , wherein the thickness of the cellular energy-absorbing structure is longer than the original length of the stretchable elongated body of the clamping device. 
     
     
         17 . Helmet according to  claim 1 , wherein said base is rigid or semi-rigid. 
     
     
         18 . Helmet according to  claim 4 , wherein each open-cell has an open base facing towards the shell and an opposite open base facing towards the head receiving system. 
     
     
         19 . Helmet according to  claim 5 , wherein the 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. 
     
     
         20 . Helmet according to  claim 10 , wherein said harness system or a comfort system being connected to the counter-base or base of the at least one clamping device.