| 摘要 |
<p>An automatically operating valve for use for example in a forecourt fuel pump has a body (10) defining a flow passage (20) within which is formed a valve seat (22), the body having a weakened zone (16) around the flow passage (20) such that an impact on the body will fracture the body at the weakened zone. A valve member (30) is mounted for movement within the flow passage (20) and is engageable with the valve seat (22) to close the valve. A closing mechanism effects movement of the valve member (30) to its closed position in the event that the body (10) is fractured at the weakened zone. Further, the valve member (30) is configured to move to its closed position under the influence of excessive flow of liquid through the flow passage (20).</p> |
