| 摘要 |
<p>A variable gas flow meter (130) for obtaining a differential pressure across a membrane (136) having a variable area orifice. The orifice is defined by a hinged flap which swings open in the direction of gaz flow. The area of the orifice enlarges with increased flow. The flow meter retains the membrane in a central housing (138a, 138b) configured to prevent the accumulation of liquids, such as moisture or mucus, which enter the line. In a first, horizontal embodiment, the housing invert (146a, 146b) is continuous and flush throughout except for negligible ridge (137) of membrane that remains when the orifice opens. In a second, vertical embodiment, the housing allows liquids in an upper conduit section to drop downward and flow out the device into a lower conduit section through the forces of gravity and a gas flow.</p> |
