Pressure pulse metering pipette - having liquid reservoir with overflow to measuring tube which discharges fixed volume through restriction when pressure is applied

摘要

Channel type pipette is for metering small quantities of liquid by a directly acting pneumatic impulse. The measuring tube is filled with liquid from a reservoir via an overflow line. A fixed pressure is then applied which corresponds to a change in level in the measurement tube. The measurement tube has a narrow outlet tube leading to U tube with an overflow on the other side. The liquid is dispensed by subjecting the measurement tube to the pressure change which causes the liquid to be displaced. For a constant pressure, a constant liquid amount is dispensed each time. Allows reproducible accuracies to be achieved which are much greater than with other devices of this type.