Flushing mechanism for toilet tank

Flushing mechanism for a toilet tank (10) arranged to permit the evacuation from the previously filled tank (10) of two different volumes of water by action on at least one control button (12), said mechanism comprising an overflow tube (1) provided, at its lower end, with a sealing valve (3, 4) coacting with an evacuation opening (5′) provided in the bottom of the tank (10), said overflow tube (1) being arranged to occupy at least three axial positions, namely a lower position for closing the evacuation opening (5′), an intermediate so-called small flush position permitting evacuation of a first volume of water and an upper so-called large flush position permitting the evacuation of a second volume of water greater than the first volume of water, control means (12, 16, 17, 21, 22) ensuring the axial movement of the overflow tube (1) from its lowest position to the intermediate position or the upper position, the mechanism moreover comprising a first so-called small flush float (30) mounted on a height adjustment screw (31) and a second so-called large flush float (40) pivotally mounted about an axle (41) fixed relative to the housing (2),

• characterized in that a housing (2) surrounds the assembly of the mechanism, said housing (2) being of a single piece in two parts articulated about a hinge (60) parallel to the axis of the overflow tube (1).