US 12,329,936 B2
Auto-injector
Yannick Hourmand, Haslingfield (GB); Timothy Donald Barrow-Williams, Herts (GB); and Matthew Ekman, Cheshire (GB)
Assigned to Sanofi-Aventis Deutschland GMBH, Frankfurt am Main (DE)
Filed by Sanofi-Aventis Deutschland GMBH, Frankfurt am Main (DE)
Filed on Mar. 29, 2024, as Appl. No. 18/622,306.
Application 18/622,306 is a continuation of application No. 18/498,416, filed on Oct. 31, 2023.
Application 18/498,416 is a continuation of application No. 16/909,107, filed on Jun. 23, 2020, granted, now 11,833,331, issued on Dec. 5, 2023.
Application 16/909,107 is a continuation of application No. 15/669,571, filed on Aug. 4, 2017, granted, now 10,729,853, issued on Aug. 4, 2020.
Application 15/669,571 is a continuation of application No. 13/993,528, granted, now 9,724,472, issued on Aug. 8, 2017, previously published as PCT/EP2011/073502, filed on Dec. 21, 2011.
Claims priority of provisional application 61/432,255, filed on Jan. 13, 2011.
Claims priority of application No. 10196067 (EP), filed on Dec. 21, 2010.
Prior Publication US 2024/0238522 A1, Jul. 18, 2024
Int. Cl. A61M 5/20 (2006.01); A61M 5/50 (2006.01); A61M 5/32 (2006.01)
CPC A61M 5/2033 (2013.01) [A61M 5/50 (2013.01); A61M 2005/206 (2013.01); A61M 2005/208 (2013.01); A61M 5/326 (2013.01)] 30 Claims
OG exemplary drawing
 
1. A method comprising:
engaging a proximal end of a syringe with an angled surface of a syringe retainer of an auto-injector to limit proximal movement of the syringe relative to the syringe retainer, the syringe containing a medicament, the angled surface being located at a proximal end of the syringe retainer;
engaging a flexible arm to a surface of a sleeve of the auto-injector to limit proximal movement of a plunger rod relative to the flexible arm, at least a portion of the sleeve being radially outward of and surrounding the flexible arm when the flexible arm is engaged to the surface of the sleeve, the flexible arm being located distal to a distal end of the syringe, the plunger rod being biased under a force of a compression drive spring and configured to displace a stopper disposed in the syringe, the compression drive spring surrounding a distal portion of the plunger rod;
distally moving a needle shroud relative to a housing of the auto-injector and against a force of a shroud spring from an advanced position in which the needle shroud extends from a proximal end of the housing by a first distance to a retracted position in which the needle shroud extends from the proximal end of the housing by a second distance that is less than the first distance such that the engagement between the flexible arm and the surface of the sleeve is released by the flexible arm being outwardly deflected out of engagement with the surface of the sleeve, the flexible arm being located distal to a distal end of the shroud spring, a diameter of the shroud spring being larger than a diameter of the compression drive spring; and
proximally moving the plunger rod relative to the flexible arm under the force of the compression drive spring to dispense the medicament from the syringe while (i) the needle shroud is in the retracted position, and (ii) the engagement between the flexible arm and the surface of the sleeve is released.