| 摘要 |
<p>There is described a valve assembly (1, 1') having a casing (2) defining a cavity (3) for passage of a fluid; and a valve (4) housed in the cavity (3); the valve (4) has first sealing means (18) cooperating with the casing (2) to divide the cavity (3) into a first and a second environment (6, 5); at least one opening (23) permitting flow of the fluid between the first and second environment (6, 5); and second sealing means (19) varying in configuration to permit/prevent communication between the first and second environment (6, 5) through the opening (23); and the second sealing means (19) also cooperate with the casing (2), on the side facing the second environment (5), to prevent the first and second environment (6, 5) from communicating fluidically through the opening (23).</p> |
