A AUTOMATIC INJECTION DEVICE OF MEDICINAL FLUID IN A SMALL SCALE WATERWORKS AND ITS CONTROLLING METHOD

摘要

PURPOSE: Provided is an automatic chemical feeder for continuously feeding chemicals into ground water while the ground water flows to a water distribution plant through a pipe by a water transportation pump, informing a manager of running out of chemicals, and preventing rupture of the pipe in winter. CONSTITUTION: The feeder comprises a chemical mixer(1) with a tank(11), a high water level sensor(12), a low water level sensor(13), and a chemical mixing motor(14) having a propeller(16) connected to a shaft(15) and installed at an upper portion of the tank(11); a control unit(2) for informing a manager of running out of chemicals when the low water level sensor(13) generates a predetermined signal and controlling valves; a start switch(21) for starting water supply operation when chemicals are refilled; a first valve (V1) installed between a ground water transportation pipe(7) and the chemical mixer(1) and selectively opened and closed so as for ground water to be introduced into the tank(11); a second valve (V2) for controlling flow of chemicals from the chemical mixer(1) to a first chemical injector(3); the first chemical injector(3) having a chemical dose adjusting nozzle(31) and being installed at an outlet of the second valve (V2); a third and a fourth valves (V3,V4) for controlling movement of chemicals being transferred from the first chemical injector(3) to a second chemical injector(4); and the second chemical injector(4) for injecting chemicals into the ground water transportation pipe(7).