| 摘要 |
<p>In a combined gas flow control regulator and pressure relief valve, the pressure relief valve includes a pressure relief member comprising a flange (20) and a sleeve (18) which is sealingly engaged with the piston rod (4) of the gas flow control regulator and is slidable relative to the piston rod (4). A spring (24) urges the flange (20) of the pressure relief member into contact with the piston head (3) of the gas flow control regulator thereby closing a gas relief aperture (22) in the piston head (3) capable of connecting a first chamber (8), which is one chamber of the gas flow control regulator, to a second chamber (9) which is a gas relief chamber from which gas can escape to atmosphere. The pressure relief member moves as one with the piston of the gas flow control regulator in normal operation of the gas flow control regulator, and the pressure relief member moves away from the piston head (3) against the action of the spring (24), independently of the motion of the piston, when excess pressure builds up within the regulator body, to allow this excess pressure to be vented to atmosphere through the second chamber (9). <IMAGE></p> |
