Abstract: This protective helmet comprises a rigid or semi-rigid external shell comprising a plurality of rigid or semi-rigid flaps joined together and a compressively deformable internal liner acting as a shock absorber, the latter also comprising several elements associated with said flaps. At least some of the flaps that constitute the external shell are capable of moving relative to each other at their respective means of connection and the elements that constitute the internal liner associated with the flaps in question are designed so that they retract inside the volume defined by the helmet during relative displacement of the corresponding flaps.

Abstract: “This protective helmet comprises a rigid or semi-rigid external shell comprising a plurality of rigid or semi-rigid flaps joined together and a compressively deformable internal liner acting as a shock absorber, the latter also comprising several elements associated with said flaps. At least some of the flaps that constitute the external shell are capable of moving relative to each other at their respective means of connection and the elements that constitute the internal liner associated with the flaps in question are designed so that they retract inside the volume defined by the helmet during relative displacement of the corresponding flaps.