Patent attributes
A drive mechanism (100) for use with a drug container (50) in a drug pump, the drug container (50) having a barrel (58) and a plunger seal (60), including a tether, an electrical actuator (101) and a gear interface. Rotation of the gear interface is controlled by the actuator (101). A gear assembly rotationally engages with the gear interface. The gear assembly includes a main gear and a regulating mechanism. Release of the tether is metered by the gear assembly through the regulating mechanism. A piston (110, 1110, 2110) is connected to the tether and is disposed in the barrel (58) and configured to translate axially within the container. A biasing member is disposed at least partially within the barrel (58) and is retained in an energized state between the piston (110, 1110, 2110) and drive housing, wherein the release of the tether controls the free expansion of the biasing member from its energized state and the axial translation of the piston (110, 1110, 2110).
