AUTO-INJECTOR

摘要

The invention relates to an auto-injector (1) for administering a dose of a liquid medicament (M), comprising:
- an elongate housing (2), a syringe (3) with needle (4) and a stopper (6),
- a drive spring (8) for pushing the needle (4) from a covered position into an advanced position, for operating the syringe and for retracting the syringe (3),
- activating means (20) for locking or releasing the spring means (8). A retraction sleeve (10) is axially movable arranged in the housing (2). The drive spring (8) bears with its proximal end against a thrust face (17) of a decoupling member (14). At least one resilient decoupling arm (18) is arranged at the decoupling member (14) for bearing against a first shoulder (19) of the plunger (9). At least one aperture (34) is arranged in the retraction sleeve (10) allowing the decoupling arms (18) to be flexed outward thus allowing the first shoulder (19) to slip past the decoupling arm (18). The aperture (34) is arranged to be angularly misaligned with respect to the decoupling arm (18) and to rotate so as to align with the decoupling arms (18) upon translation of the retraction sleeve (10) out of the proximal position in distal direction (D).