摘要 |
A headgear adjustment mechanism is provided that includes a worm (30) having a central axis of rotation (A), a first headband element (13a), a second headband element (13b), a spur gear (20), and a housing (59). The first headband element includes (i) a worm rack (19) disposed in operative engagement with the worm, and (ii) a first pinion rack (15a). The second headband element includes a second pinion rack (15b). The spur gear is disposed in simultaneous operative engagement with the first pinion rack and the second pinion rack, and the housing at least partially encloses the first and second headband elements. During operation of the adjustment mechanism, rotation of the worm about the axis of rotation causes the first headband element and the second headband element to translate in opposite directions with respect to the worm, thereby adjusting a fit of the headgear. |