Low-high flow rate valve

Abstract

A float operated valve for controlling the rate of flow of water from a pipe carrying water under pressure, to a vessel, comprises a pipe having an end opening of selected diameter and a flange of larger diameter surrounding the pipe. A flexible diaphragm is attached over the flange having a central closure pad adapted to cut off water flow when pressed against the pipe. A small orifice is drilled through the diaphragm so that when the flow is shut off, water can still flow through the orifice to the second side of the diaphragm. A second short pipe having a similar flange is bolted against the diaphragm to the first flange, to provide a water tight seal. There is a second small orifice in the second end of the second pipe, and a float mechanism is provided with a closure tip to close the second orifice when the water level is at a selected value. The closure tip varies the size of the second orifice so that the orifice is responsive to the float. Depending on the ratio of areas of the first and second orifices, water pressure on the second side of the diaphragm prevents flow. When the second orifice reaches a selected ares the diaphragm no longer seals the first pipe and a high flow of water is provided. A removable, resilient insert in the first pipe seats the diaphragm. The resilient insert minimizes valve maintenance while prolonging component service life. An anti-syphon relief prevents reverse fluid flow during vacuum or negative pressure conditions. The relief causes air to enter the valve to break the suction created by the vacuum or negative pressure condition while preventing water loss during normal operations.