| 摘要 |
A dual flush valve (1) comprises a housing (10) having an outlet (2, 36) and a main valve assembly (34) movable within the housing between a raised position in which the valve is open and a lowered position in which the valve is closed. An operating system (14) is actable in response to an input to raise the main valve assembly (34) off its seat (2A) so that it is subjected to an upwards force by immersion fluid entering the outlet. In response to a first actuation input, the operating system exerts a first downward force on the main valve assembly (34) so that the main valve assembly is caused to descend when the fluid in the cistern reaches a first predetermined intermediate fluid level (31) to provide a partial flush. In response to a second actuation input the operating system exerts a second downward force on the main valve assembly (34) which is lower than the first downward force so that main valve assembly is caused to descend when the fluid in the cistern reaches a second predetermined intermediate fluid level (32) lower than the first intermediate fluid level to provide a full flush. |
