US Patent 10448691 Football helmet with movable flexible section

A protective helmet comprises a shell comprising a non-linear slit at least partially surrounding and defining a flexible section movable relative to the shell. The helmet further comprises an energy absorbing layer contacting an inner surface of the shell and an inner surface of the flexible section. Internal padding is operably coupled to the energy absorbing layer. The shell has a perimeter, and the non-linear slit does not extend to the perimeter of the shell. The flexible section moves relative to the shell upon the helmet receiving an impact energy to dampen the impact energy.