GB1117516A - Improvements in diaphragm pumps - Google Patents

Abstract

1,117,516. Diaphragm pumps. T.H. BAGGALEY. June 8, 1967 [July 8, 1966], No. 30839/66. Heading F1A. A diaphragm pump for supplying accurately controlled quantities of liquid, e.g. additives to a stream of boiler feed water or chemicals in process plant, comprises a spring-loaded diaphragm 3 defining a pumping chamber 8 and an actuating chamber 4, a solenoid valve or valves being controlled to alternately connect chamber 4 to a source of compressed air and exhaust to reciprocate the diaphragm at a rate controlled by a device feeding electrical pulses to the valve or valves. The diaphragm stroke is adjusted by a stop 15, the setting of which is indicated by a pointer 18. A single solenoid valve may alternately connect chamber 4 to pressure and exhaust, or one valve may connect the chamber to pressure, and another valve connect it to exhaust. The electrical pulses may be supplied by a mechanical timer incorporating a switch operated by exchangeable multi-lobed cams to provide different pulse frequencies, or by an electronic timer incorporating an infinitely variable capacitor. For feeding proportionate quantities of liquid to a pipeline, the pulses are supplied by a device controlled by a flowmeter in the pipeline, the flowmeter incorporating rotating magnets which actuate a reed switch controlling a pulse generator, Fig. 4 (not shown). A hand-actuated piston pump is connected to the pumping chamber for priming the diaphragm pump and discharging small quantities of liquid, Fig. 1 (not shown).