| 摘要 |
<p>An interface valve control system for use with a primary, or interface (6), vacuum-operated valve, and characterised in that a secondary valve, that is itself vacuum operated and that, is actuated by the same vacuum as is applied to a tank (2), such that if the actuating vacuum drops significantly then the secondary valve operates to close the primary, interface, valve (6) thus preventing further liquid being drawn into the transport system's collecting pipe; said secondary valve connecting a vacuum source to the interface valve (6), which is of a type having a through-passageway body (21) with a valve member (30) mounted therewithin actuated by a pressure differential between atmospheric air and vacuum across the valve the body (21) being flexible such that under an applied perpendicular force it deforms, whereby the valve member (30) flexes inside the body (21) to open the valve (20); and a timer to control how long the interface valve (6) is kept open.</p> |
