| 摘要 |
<p>A helmet comprises a shell, a visor, a face seal, a biasing means and two guiding mechanisms. The two guiding mechanisms, each located on a different side of the shell, connect the visor to the shell. Under a bias of the biasing means, the guiding mechanisms are operative to guide the visor along a pre-determined trajectory defined by the geometry of the guiding mechanisms. Each one of the two guiding mechanisms is further provided with a guiding track arrangement which comprises a first track portion and a second track portion. The first slider slidingly engages the first track portion while the second slider slidingly engages the second track portion. The pre-determined trajectory extends from a retracted position where the visor is substantially proximate a front portion of the shell and substantially outside a field of view of the wearer to a deployed position where the visor is substantially below the frontal lower edge and within the field of view of the wearer, and further towards a rear portion of the helmet to a resting position aft of the deployed position. In use, the face seal, which is located at a lower portion of the visor, is operative to substantially perpendicularly contact a face of the wearer at a position between the deployed position and the resting position.</p> |
