Abstract: Device for a lavatory cistern including: a) a flush valve opened by the lowering of a horizontal cam (13) pushing on a horizontal valve (11) which separates a ball (10) from its sealing seat; and b) a dual flushing volume mechanism, with an emptying tube (25) carrying a base floater (31), an intermediate floater (32) and, at its upper portion, a horizontal projecting element (33) which is optionally locked in its ascending stroke according to whether a weak or heavy flushing is selected.

Abstract: A computing and metering device allows only predetermined controllable quantities of a liquid to be discharged from a liquid outlet aperture. A turbine flow meter drives a metering means having a rotatable plate which carries a ball that is located in such a way as to block the arrival of the liquid when the plate is moved through a given angle of revolution from a position which is predetermined by a setting component. The flow meter and the metering means are disposed in separate chambers and are in communication with each other via an external duct through which the whole of the liquid flow passes from one chamber into the other chamber.