Abstract: A drug delivery device comprising a pumping system (4) and a liquid reservoir (7) fluidly connected to a delivery system outlet (12), the liquid reservoir comprising an elastic plunger (14) sealingly slidable within a container wall (13) of the liquid reservoir for expelling liquid out of the reservoir. The pumping system comprises a piston pump (5) comprising a plunger actuator arranged to displace the plunger (14), and a dosing unit (6) arranged downstream of the liquid reservoir (7) and fluidly connected to the liquid reservoir. The dosing unit (6) comprises a chamber portion (22) arranged between an inlet valve (24) and an outlet valve (26), the chamber portion (22) arranged to receive from the liquid reservoir a pump cycle volume of liquid under an operational pressure greater than ambient pressure generated by the piston pump, and to the deliver said pump cycle volume of liquid to the delivery system outlet, said pump cycle volume being dependent on the operational pressure.

Abstract: Micropump (10) including a support structure (14), a pump tube (16), and an actuation system (18) comprising one or more pump chamber actuators (28), the pump tube comprising a pump chamber portion (24) defining therein a pump chamber (26), an inlet portion (20) for inflow of fluid into the pump chamber, and an outlet portion (22) for outflow of fluid from the pump chamber. The inlet, outlet and pump chamber portions form part of a continuous section of tube made of a supple material. The one or more pump chamber actuators are configured to bias against the pump chamber portion to expel liquid contained in the pump chamber via the outlet portion, respectively to bias away from the pump chamber portion to allow liquid to enter the pump chamber via the inlet portion. The pump chamber portion has a cross-sectional area Ap in an expanded state that is larger than a cross-sectional area Ai of the pump tube at the inlet and outlet portions.