| 摘要 |
A valve has a valve member (8) carried on a displaceable element (12). The displaceable element (12) is resiliently biased towards the closed position of the valve but is normally held in the open position by magnets (64). A release winding (32) can be energized to overcome the magnetic field of the magnets (64), so allowing the valve to close. The release winding (32) may be energized in response to predetermined circumstances, for example flow through the valve for longer than a predetermined time. |
