| 摘要 |
<p>A flexible membrane (12) with central circular stiffener (15) divides the body into two sections (2, 3), one (2) being connected to the inlet port (4). The exit port (5) has a tubular extension with a chamfered end (6) which bears on the central portion of the membrane. Two holes are made in the membrane one (13) in the centre being larger than the other (14) nearer the rim. On the other side of the membrane from the exit port, a conical spring (27) loaded plug (18) has limited axial freedom in the actuating sleeve (19) and its point controls the central orifice in the membrane. The actuating sleeve may be moved axially in a boss (17) in the body. When off, the membrane is in contact with the exit port chamfer and the plug closes off the central hole, pressures on either side of the membrane equalising by virtue of the small bleed hole (4).</p> |
