GB1157219A - Improvements relating to Liquid Mixing Systems - Google Patents

Abstract

1,157,219. Mixing flowing liquids in proportions. COVENTRY CLIMAX ENGINES Ltd. 19 Feb., 1968 [15 March, 1967], No. 12228/67. Heading B1C. In apparatus for mixing water and a liquid foam forming compound, the flow of one of the liquids is controlled by a governor valve which is subjected to opposed biassing forces derived respectively from flow sensing means in one of the liquids, and in the other liquid or in the mixture. As shown foam compound is pumped through inlet 10, ports 12, 14 in the sleeve valve 13, outlet 16, pipe 4, orifice 36 and pipe 6; the flow through the sleeve valve 13 does not exert any bias on it as its closed ends are of equal area but it is subjected to the bias in a downward direction on the connected piston and diaphragm assembly 22, 23, 24 caused by the pressure drop across the orifice 36 acting through pipes 4, 45. The foam forming compound is mixed with water in the pump 7, 8 and the mixture is discharged through a restriction 9 the pressure drop across which acts through pipes 43, 44 to bias in an upward direction the piston and diaphragm assembly 27, 28, 29, the bias being transmitted by push rod 26 to the sleeve valve 13. The valve takes up an equilibrium position in which the flow through parts 12, 14 is adjusted to a rate at which the biasses are equal. As described there are seven orifices 36 of equal size each providing a one per cent admixture and a plate 37 can be rotated so that a cut-away portion 40 uncovers any desired number of them.