Patent ID: 8632496

Claim:
An assembly comprising: a medical pump subassembly, the medical pump subassembly comprising: a magnetic cup forming a recess, wherein the magnetic cup includes a protrusion within the recess, wherein the cup forms a central aperture through the protrusion, an electromagnetic coil within the recess and circumscribing the protrusion, a weld ring surrounding the recess, a barrier plate covering the recess, a sleeve within the central aperture, wherein the sleeve forms a bore configured to receive a piston, wherein the barrier plate forms a mating aperture that coincides with the central aperture of the cup, a first seal between the weld ring and the barrier plate, and a second seal between the sleeve and the barrier plate, wherein the first seal and the second seal combine to fluidically separate an interior of the cup from an external surface of the barrier plate; a bulkhead including a bay, wherein the medical pump subassembly is mounted within the bay; and a third seal between the cup and the bulkhead to fluidically separate an exterior of the cup from an external surface of the barrier plate.