Abstract: A drug-delivery device is provided including a drug reservoir configured to contain a fluid drug, a needle cartridge comprising a plurality of needle assemblies, a drive member, a pump, one or more springs, a loading button and a dosing button. The device is configured to use work done by the user in actuating the loading button to load the one or more springs. When the user actuates the dosing button after actuating the loading button, the device is configured to (i) release the one or more loaded springs to operate the drive member to drive a needle assembly that is in operational alignment with the drive member from a retracted position to an injection position, (ii) drive the pump to pump fluid drug from the drug reservoir through the driven needle assembly, and (iii) retract the driven needle assembly from the injection position to the retracted position.

Abstract: A rotary sub-assembly for pumping of fluid is provided. The sub-assembly includes a hollow body defining a cavity having a longitudinal axis, the body comprising a cavity wall with at least two ports passing therethrough. At least a portion of the cavity has a non-circular cross-section such that a first constant or varying radial distance from the longitudinal axis to inwardly-offset segments of the cavity wall surrounding the two ports is less than a second constant or varying radial distance from the longitudinal axis to second segments of the cavity wall spaced apart from the two ports. A rotatable plunger is housed in the cavity. The plunger is sized and shaped such that a side wall of the plunger can establish a liquid-tight seal against the inwardly-offset segments of the cavity wall, but does not establish a liquid-tight seal with the second segments of the cavity wall spaced apart from the two ports.

Abstract: A rotary sub-assembly for pumping of fluid is provided. The sub-assembly includes a hollow body defining a cavity having a longitudinal axis, the body comprising a cavity wall with at least two ports passing therethrough. At least a portion of the cavity has a non-circular cross-section such that a first constant or varying radial distance from the longitudinal axis to inwardly-offset segments of the cavity wall surrounding the two ports is less than a second constant or varying radial distance from the longitudinal axis to second segments of the cavity wall spaced apart from the two ports. A rotatable plunger is housed in the cavity. The plunger is sized and shaped such that a side wall of the plunger can establish a liquid-tight seal against the inwardly-offset segments of the cavity wall, but does not establish a liquid-tight seal with the second segments of the cavity wall spaced apart from the two ports.