| 摘要 |
<p>A dual discharge valve for immersion in a cistern (14), which comprises a housing, an upwardly movable main valve assembly (30) within the housing, a first vent means (9), a central stem (19) extending upwardly from the main valve assembly and actuable by a first opening means (20) to raise the main valve assembly off its seat, whereby on raising the main valve assembly immersion fluid can enter the outlet, the net upward force acting on the assembly thereby causing full flow of the immersion fluid through the outlet and a second operating means (21, 47), to raise the main valve assembly and then to exert a downward force on the main valve assembly, so that a predetermined intermediate water level (36), the main valve assembly re-seats.</p> |
