摘要 |
<p>A valve 14 that includes a valve seat 20 and a flap 22 that has a surface 57 that has been ablated. Through use of an ablated flap, the flap characteristics can be better fashioned to achieve desired valve performance. The valve flap can be fashioned to remain closed under any orientation but also to open with minimal force or pressure from the flow stream. A valve having these qualities provides a valve can operate more efficiently, which may be particularly beneficial when used one respiratory masks where the valve is powered by the wearer.</p> |