Patent ID: 8146177

Claim:
A protective helmet, for sports and work use, comprising a rigid outer shell, the outer shell comprising a front cap ( 2 ) having a concavity able to cover at least the upper part of the cranium, and a rear cap ( 3 ) having a concavity able to cover the rear part of the cranium, wherein said caps ( 2 , 3 ) are mutually movable, the rear cap ( 3 ) being connected to the front cap ( 2 ), in such a manner as to rotate relative to front cap ( 2 ) about an axis (A) transverse to the vertical plane of symmetry of the cranium, between a raised position and a lowered position, further comprising an inner shell ( 8 ) to absorb impacts intended to remain interposed between the cranium and the outer shell, and an adjustment unit ( 83 ) for contracting/enlarging said inner shell ( 8 ) in order to vary its edge perimeter, wherein said adjustment unit is controlled by the outer shell's rear cap ( 3 ), such that rotating the rear cap ( 3 ) towards a lowered position results in contraction of the inner shell ( 8 ).