摘要 |
A servo operated liquid level control valve including a flexible diaphragm (120) a central portion of which is closable onto a seating (116) surrounding a low pressure outlet and an outer part of which on that side which contacts the seating being subjected to inlet pressure at all times, the inlet pressure being able to communicate with a control chamber (124) on the other side of the diaphragm (120) by way of a restricted opening (126) and a pilot valve member (128) being provided for allowing fluid under pressure to escape from said control chamber (124) to cause the valve to open, said pilot valve member being under the control of a control element (144). So that the valve can be of relatively simple construction, and so that the risk of leakage of fluid can be virtually eliminated, the control element is not directly connected to the pilot valve member but has magnetic attraction relative thereto via a magnet (140). <IMAGE> |