| 摘要 |
<p>A lockable valve (7) for a fuel line contains a fuel inlet (2) and fuel outlet (3) which communicates with one another via a passage (6) in which is located a spring-biased piston (15) which is responsive to a pressure change in the fuel line. Associated with the piston (15) is a spring biased plunger (11) which controls a valve (8) to close or restrict the flow of fuel through passage (6). At the other end of the piston (15) is a resetting device (23, 24) which requires an unlocking action before the piston can be extended to withdraw the plunger 11 so as to open the valve. When a fall in pressure is detected by the piston (15), it causes operation of the valve (8) to stop or restrict fuel flow but this operation may only be reversed by the unlocking action.</p> |
