GB644569A - Improved apparatus for delivering predetermined volumes of liquid - Google Patents

Abstract

644,569. Delivering measured quantities of liquid. LIPKAU, M. A. Aug. 22, 1946, Nos. 25055 and 25056. Convention dates, Sept. 21, 1945. [Class 106(v)] Apparatus for the delivery of measured volumes of liquid comprises a metering receptacle provided with ports at different heights, discharge of liquid being effected by compressed air, and is characterised by the provision of pan-like extensions to the ports for the purpose of separating, towards the end of the delivery operation, a small volume of liquid in the pans from the main bulk of liquid in the metering receptacle, the said small volume of liquid then discharging quickly. As shewn in Fig. 1 a receptacle 1 has secured thereto a tube 4 having ports 5 provided with pans 6. Within the tube 4 is a second tube 7, rotatable by handle 10 and having ports 5' each of which, at a given rotary position of the tube 7, co-operates with an appropriate port 5. Initially a source of vacuum connected at 34 draws liquid from a reservoir connected to inlet 13 through port 14 and fills the receptacle 1, whereon float valve 20 operates to cut off the vacuum source. Rotation of handle 10 closes port 14 and moves cam 32, closing valve 18, and also opens compressed-air inlet valve 10, Fig. 3, filling chambers 21 and 21<SP>1</SP> with compressed air, the chambers 21 and 21' being inter-connected by a one-way valve 22, Fig. 4. Further rotation of the handle brings the upper pair of ports 5, 5<SP>1</SP>, into alignment and at the same time cam 32' opens valve 23 allowing compressed air in chamber 21 to pass via conduits 24, 25, 26, chamber 28 and conduit 27 to receptacle 1, thus driving out the liquid through port 17 and tube 16. At the end of the delivery air is exhausted through conduit 30 and outer duct 31, bubbling through the liquid thus being prevented. Continued rotation of the handle brings the lower pair of ports 5, 5<SP>1</SP> into alignment and opens valve 23<SP>1</SP>, air being then exhausted from chamber 21' and, through valve 22, from chamber 21. An integrating meter, not shewn, is actuated by handle 10 and records the total number of units delivered. The Specification as open to inspection under Sect. 91 also describes a modification, Fig. 5 (Cancelled), comprising valves 41 operated by cams 42. This subjectmatter does not appear in the Specification as accepted.