Water and energy saving closet tank flush valves

Claim 1

A toilet tank flush valve system which permits emptying of the tank from the normal storage level to either one of two pre-set water levels comprising a drain valve structure installed in a toilet tank in the form of a non-flotable hollow valve member fixed to a hollow support stem slidably mounted to a fixed support structure, said valve member adaptable to seating upon and closing a drain outlet at the bottom of an installed toilet tank, said fixed support structure being in the form of a hollow vertical tube concentrically mounted about the said support stem and valve member, with said tube fixed about the drain outlet of the toilet tank, said tube extending upwards above said drain outlet, said tube formed with a through opening at its lower end to permit water to flow from said tank into the drain outlet when the valve member is unseated from the drain outlet, with a first float mounted to a first float lever pivotally fixed to said support structure and a second float mounted to a second float lever pivotally fixed to said support structure, with each float lever extending through an opening in the tube of the support structure, and with the float of each float lever fixed to the first end section of its respective float lever that extends externally beyond the said tube, with each of the two float levers fitted at its second end section, that extends inside the said tube, with individual means to engage the support stem when the individual float of the float lever is in a first position in which it is buoyed by water in the tank at or above the level of the respective float, said means being free of engagement with the support stem when the respective float has rotated to a second position of lesser buoyancy than the first position in response to a lowering of the level of water in the tank, said means of engagement serving to limit downward movement of the said support stem, while permitting upward movement of the support stem in the installed position, in the first position of each float, said float levers located on the support structure such that each float is responsive to a different level of water in the tank in individually rotating from the first position to the second position, with the support stem linked to an operating lever fixed to a handle structure mounted to the wall of a toilet tank, said handle structure fitted with means to vertically lift the support stem alternately to either a first position of limited travel or a second position of full travel, said support stem engaging the first float lever when initially moved to said first position limited travel and engaging the second float lever when moved to said second position of full travel, when the tank contains water at the normal storage water level of the tank, together with a refill supply tube extending freely into the top opening of the hollow support stem and located so as to not interfere with vertical movement of said stem, such that water flowing out of said refill tube into the interior of the hollow support stem will flow through the hollow valve member into the drain outlet, when said valve member is seated or unseated upon the drain outlet.