| 摘要 |
<p>A fluid flow valve such as a faucet or air-purge valve comprising a housing (1) having defined therein a fluid through-flow aperture (6) with a valve seating (5) formed in the housing and bounding said aperture. A flexible closure membrane (11) is secured at one end to the housing (1) and is adapted to be biased, under fluid pressure in the housing, against the valve seating so as to seal the aperture. Membrane displacing means (8, 9) are secured to an opposite end of the membrane (11) so that displacement of the displacing means in a first sense progressively detaches successive transverse portions of the membrane from the seating (5) so as to open the aperture (6) whilst displacement of the displacing means in an opposite sense allows for the membrane to become sealingly biased against the seating.</p> |
