SPLIT PISTON METERING PUMP

摘要

A micropump according to the invention uses axially oriented pistons to define a pump volume. Translating the pistons axially with respect to each other within a pump housing draws a metered amount of fluid into the pump volume from a reservoir port for delivery to a cannula port when the space is collapsed. Radially situated seals on the pistons cooperate with the axial movement to close off and open the cannula port and the reservoir port respectively at different positions of the piston stroke.

主权项

1. A micropump for delivery of medication by infusion, comprising:
a reservoir; a cannula; a motor; a gear; a drive rack; a tubular pump housing having a first aperture in fluid communication with the reservoir and a second aperture in fluid communication with the cannula; a drive piston and a floating piston axially oriented within the pump housing; the drive piston and the floating piston being positioned to close the first and second aperture at first and second axial positions, respectively, of the drive piston and floating piston within the pump housing; wherein the motor is engaged to the gear and the gear is engaged to the drive rack to translate the drive piston axially with respect to the floating piston, wherein translating the drive piston with respect to the floating piston defines a pump volume space within the pump housing.