US 10,376,650 B2
Drug delivery device and method for a drug delivery device
Michael Helmer, Frankfurt am Main (DE); Christoph Eissengarthen, Ginsheim (DE); Winfried Huthmacher, Frankfurt (DE); and Carsten Mosebach, Mainz (DE)
Assigned to Sanofi-Aventis Deutschland GMBH, Frankfurt am Main (DE)
Filed by Sanofi-Aventis Deutschland GmbH, Frankfurt am Main (DE)
Filed on Jun. 13, 2017, as Appl. No. 15/620,993.
Application 15/620,993 is a continuation of application No. 14/346,507, granted, now 9,707,352, previously published as PCT/EP2012/069032, filed on Sep. 27, 2012.
Claims priority of application No. 11183300 (EP), filed on Sep. 29, 2011.
Prior Publication US 2017/0281874 A1, Oct. 5, 2017
Int. Cl. A61M 5/24 (2006.01); A61M 5/31 (2006.01); A61M 5/315 (2006.01)
CPC A61M 5/31536 (2013.01) [A61M 5/24 (2013.01); A61M 5/31511 (2013.01); A61M 2005/3103 (2013.01); A61M 2207/00 (2013.01); Y10T 29/4978 (2015.01)] 18 Claims
OG exemplary drawing
 
1. A method for assembling a drug delivery device, the method comprising:
providing a cartridge unit, the cartridge unit comprising a cartridge which holds at least one dose of a drug and a bung being movably arranged within the cartridge,
providing a drive unit which is connectable to the cartridge unit, the drive unit comprising a piston rod and a mechanism, wherein the mechanism is configured to move the piston rod by a back off distance when the mechanism switches from an activated state into a deactivated state,
activating the mechanism to move the piston rod distally,
measuring a position of a proximal end of the bung with respect to a predetermined reference point on the cartridge unit,
measuring a position of a distal end of the piston rod with respect to a predetermined reference point on the drive unit,
deriving, from measuring the position of the proximal end of the bung and measuring the position of the distal end of the piston rod, information indicative for a relative position of the distal end of the piston rod and the proximal end of the bung,
deactivating the mechanism such that the piston rod is displaced by the back off distance,
connecting the cartridge unit and the drive unit to one another such that the piston rod and the bung are arranged at an initial distance from one another when the mechanism is deactivated.