GB677535A - Reagent distributing and measuring device - Google Patents

Abstract

677,535. Delivering measured quantities of liquids. L' AUXILIAIRE DES CHEMINS DE FER & DE L'INDUSTRIE. July 12; 1949 [Feb. 28, 1949], No. 18406/49. Class 106 (v). A device for delivering a liquid reagent in quantities proportional to the quantity of liquid to be treated comprising a fluidtight chamber 10 provided with an overflow pipe 15 and connected with an air bell 2, the base of which opens into a tank 1 containing the liquid to be treated, is characterised in that the inlet opening for supplying the liquid to be measured out is connected to the fluid-tight chamber 19 by a hydraulic joint which may accommodate a pressure head at least equal to that created in the fluidtight chamber 10 by filling the tank 1 and that ensures the overflow of liquid into an overflow pipe 15 to the tank fluidtight cover. The fluidtight chamber 10 which has a filling tube 12 is connected with the air bell 2 by a U-tube 5, the limb 5b connected with the chamber 10 being provided with a tube 7 open to the atmosphere. On filling the tank 1, liquid enters the air bell 2 through an orifice 3 so that the pressure in the air bell 2 and the U- tube limb 5a is increased. This increase of pressure is transmitted through liquid 6 in the U-tube 5 to the other limb 5b with the consequent closing of the tube 7 by liquid 6. The rise in pressure in the other U-tube limb 5b and the fluid tight chamber 10 causes the rise of reagent in a bell 14 towards the top of the overflow pipe 15. When the U-tube liquid 6 is depressed to the junction of the two limbs 5a, 5b, air bubbles through the liquid 6 from the air bell 2 to the fluidtight chamber 10 thus causing an overflow of reagent through the pipe 15 to the tank 1 in a quantity proportional to the amount of air displaced from the air bell 2. On emptying the tank 1 air passes back to the air bell 2 through the U-tube liquid 6 or a capillary tube 9 which joins the limbs 5a, 5b of the U-tube 5 so that the tube 7 is eventually opened to the atmosphere and syphoning of reagent into the U-tube 5 or the air bell 2 is prevented. In a modification (not shown) a gravity feed tank 17 is arranged above the fluidtight chamber 10 and connected with it by a U-tube forming a hydraulic joint.