Patent ID: 8469930

Claim:
A dosing unit for an ambulatory infusion device, comprising: a stationary member; a movable member, the movable member and the stationary member, in combination, making a charging valve and a discharging valve, the charging valve being adapted to be in fluid communication with a drug reservoir and the discharging valve being adapted to be in fluid communication with an outlet assembly, wherein the movable member is movable between a charging valve position, in which the charging valve is open and the discharging valve is closed, and a discharging valve position, in which the discharging valve is open and the charging valve is closed; and a plunger, located, at least in part, in a metering cavity of the movable member and being adapted for displacement in the metering cavity along a displacement axis between a distal plunger end position and a proximal plunger end position, the displacement axis being a pivoting axis of the movable member, the plunger being in a threaded engagement with the movable member, wherein the plunger is adapted to couple continuously to a driving unit and the movable member is adapted to selectively couple to the driving unit, such that, by operating the driving unit with the movable member being coupled with the driving unit, the movable member moves with the plunger as to maintain a position along the displacement axis being maintained, and that, by operating the driving unit with the movable member being decoupled from the driving unit, the plunger is displaced while a position of the movable member is maintained.