Apparatus and a method for metering liquids

Abstract

Apparatus for metering one or more liquids contained in respective reservoirs (2, 6) into one or more collecting containers is characterized in that it comprises, for each liquid: a cylinder (2) for the liquid to be metered, the cylinder having a movable piston member (8) in contact with the surface of the liquid in the cylinder (2), pressure means (12) for exerting a constant force on the piston (8), means (14, 16, 18, 20) for the transfer of the liquid from the cylinder (2) to the collecting container, the transfer means comprising a duct having an inlet opening (16) for the withdrawal of the liquid from the cylinder and a delivery opening (20), the transfer means being movable in dependence on the level of liquid in the cylinder (2) and being arranged to keep the geometrical height difference H1 between the withdrawal point and the delivery point proportional to the hydrostatic head of liquid H2 above the withdrawal point with variations in the level of liquid in the cylinder so as to keep the delivery flow-rate constant, and valve means (22) associated with the transfer means for controlling the flow of liquid in the transfer means.

Dependencies are inferred from the claim text.