Toilet flush tank mechanism

Claim 1

In combination with a flush tank of the type including (1) a lower outlet for draining water from the tank, (2) a byouant flap-type valve member supported within said tank for up and down swinging out of and into position closing said outlet, (3) means operative to automatically fill the tank with water to an upper level therein and (4) an actuator supported from said tank for selective shifting between either of two actuating positions from a rest position, a control mechanism disposed in said tank and operatively associated with said valve member and actuator to raise said valve member from said outlet in response to shifting of said actuator to a first actuating position for subsequent lowering buoyant the bouyant valve member to its closed operative position as the water level in said tank is lowered past the level of the raised valve member, said control mechanism also including means operatively associated with said valve member to raise the latter from said outlet in response to shifting of said actuator to the second actuating position thereof, and to exert a downward force on said valve member sufficient to overcome the positive buoyancy thereof as the level of water in said tank is lowered past a low water level spaced below said upper level and appreciably above said outlet, the last mentioned means including a rocking arm oscillatably supported intermediate its opposite ends of said tank and to which said actuator is connected to oscillate said arm between limit positions of oscillation thereof in response to shifting of said actuator between its actuating positions, one way connecting means operatively connecting the opposite end portions of said arm to said valve member for raising the latter in response to said arm being pivoted to either of said limit positions of oscillation thereof, a vertically shiftable float guidingly supported in said tank for movement between upper and lower positions, said connecting means including a rigid portion thereof engaged with said valve member and engageable with said float upon shifting of said actuator to one actuating position thereof and lowerable with said float to urge the valve member downwardly toward said outlet as said water level drops to said lower level, said rigid portion, when said actuator is shifted to its other actuating position thereof, being shifted away from engagement with said float.