Patent ID: 6159186
Filing Date: 2000-12-12
Classification: A61M

Abstract:
Apparatus for controlling infusion delivery via a drop chamber having an inlet for liquid, an outlet below the inlet, and a space between the inlet and the outlet, the apparatus comprising:drop detection means for detecting each drop of a plurality of drops falling through the chamber and for providing a trigger signal on detection thereof;a light source ressponsive to the trigger signal to illuminate falling drops briefly for recordal of a frozen image thereof;imaging means defining a two-dimensional multi-pixel array for acquiring data corresponding to two-dimensional images of drops falling through the drop chamber;first processor means for calculating the volume of the drops from the data by calculating the number of pixels in each drop image, and for calculating the liquid flow rate through the drop chamber from the calculated volume of the imaged drops and the number of drops detected; andcontrol means for comparing the calculated liquid flow rate with a desired or predetermined flow rate value and for controlling the flow rate of liquid entering and/or leaving the drop chamber to correspond to the desired or predetermined value.