Water saving water closet tank

Claim 1

In a reservoir tank for water closets, the combination including a vertical closed tank having top and bottom walls, said bottom wall having a first discharge opening for connection with the inlet of a water closet bowl, attachment means to secure the tank to a bowl, plug means to close said first discharge opening, said plug means including a vertical pipe projecting upwardly through a second opening provided in said top wall, said tank also being provided with an inlet for connection with a water supply pipe and float valve means including a third opening in communication with the atmosphere at the top of the tank, said float valve means being mounted to close said third opening when the tank is full and to uncover said third opening when the water in the tank is below a predetermined level, said pipe being vertically slidable in sealing engagement with said opening to uncover said first discharge opening to permit water to enter a bowl directly from the tank and the water supply pipe, said vertical pipe being provided with an aperture to establish communication between the atmosphere and the interior of the vertical pipe, the lower end of the interior of the vertical pipe being in communication with said first discharge opening below said plug means, the top wall of said tank including an enclosed chamber having a pair of spaced walls, said vertical pipe extending through at least one of said spaced walls, said aperture in the vertical pipe being longitudinally slotted to establish communication between the interior of the enclosed chamber and the atmosphere, and said third opening being disposed in the other of said pair of spaced walls of said chamber.