US 12,274,872 B1
Collar hold detent mechanism and lock for injection devices
Alexander Hee-Hanson, Melbourn (GB); Thomas Lever, Melbourn (GB); Michael Parrott, Melbourn (GB); and Robert Wilson, Melbourn (GB)
Assigned to Genzyme Corporation, Cambridge, MA (US)
Filed by Genzyme Corporation, Cambridge, MA (US)
Filed on Mar. 28, 2024, as Appl. No. 18/620,097.
Int. Cl. A61M 5/32 (2006.01)
CPC A61M 5/322 (2013.01) [A61M 5/326 (2013.01); A61M 2005/3267 (2013.01); A61M 5/3271 (2013.01)] 27 Claims
OG exemplary drawing
 
1. An injection device comprising:
an injection device body;
a needle shroud retractable into the injection device body comprising a shroud pin;
a control spring coupled to the needle shroud and biased to cause the needle shroud to be at least partially extended from the injection device body in an initial position; and
a collar rotatable with respect to the injection device body and comprising a cam track engageable with the shroud pin;
a hold detent mechanism coupled to the cam track of the collar, wherein the hold detent mechanism is configured to:
activate, when the needle shroud is retracted from a first position on the cam track into the injection device body to a hold position on the cam track, by engaging the shroud pin thereby creating a hold detent force opposite a control spring force caused by compression of the control spring during said retraction of needle shroud to said hold position; and
deactivate, when the needle shroud is extracted from the hold position on the cam track subsequent to the retraction towards a second position on the cam track, by disengaging the shroud pin thereby releasing the hold detent force and enable the needle shroud to extend from the injection device body to the second position on the cam track; and
wherein the hold detent mechanism further comprises a non-return surface configured to, subsequent to the extension of the needle shroud, prevent further retraction of the needle shroud into the injection device body along the cam track towards the hold position.