Portable fluid infusion apparatus

摘要

A portable infusion device includes a disposable syringe which is located in a removable section of a compact package that comprises the device. In order to conserve space, a flexible piston rod assembly is provided wherein the syringe plunger head is connected to a thin flexible plunger stem which is reversely bent about the upstream end of the syringe body so that the outer end of the stem lies directly adjacent and parallel to the syringe body. A small motor located in the non-removable portion of the package drives the plunger through a screw which sequentially engages closely spaced teeth on the face of the plunger stem as it moves along the outer surface of the syringe. When the syringe contents have been discharged, the removable section, including the syringe and plunger stem assembly, can be readily removed and replaced.