US Patent 7261275 Relief valve for use in a diaphragm flush valve

An improved relief valve for use in a diaphragm flush valve is constructed having a sealing member provided with an exteriorly threaded shaft extending down into the diaphragm flush valve with a smaller diameter metal stem extending from the bottom of the shaft, a sleeve member slidable along the metal stem and having a vertically aligned slit in its side wall, and a retaining member adjustably vertically positioned on the threaded sealing member shaft, wherein the retaining member having a stop element extendable into the vertical slit to prevent the sleeve member from dropping further than a predetermined distance from the bottom of the threaded shaft.