Liq. flow monitor with constant head chamber - has pressure transducing diaphragm controlling output valve in accordance with liq. level fluctuations between preset thresholds

摘要

A fluid flow device for monitoring the parameters of a flowing liquid includes a chamber (15) into which the liquid enters via an input (5). A diaphragm (29) transmits pressure signals to a control box (25) indicative of the level of liquid inside chamber (15) above the diaphragm level. In the base of chamber (15) a reciprocating valve unit (28) is provided whereby fluid may be released into a secondary chamber (10) to output (7). A fall in fluid level below a preset level (40) causes the control unit to actuate valve (28) to close on its seat (11) whereas a rise in fluid level above higher preset level (41) initiates opening of the valve.