Automatic injector with needle retraction after injection

摘要

The invention concerns an automatic injector comprising a syringe reservoir (12) provided with an injection needle (14) and mounted mobile in the injector body (10), between a retracted position in the body, and an injection position. It comprises an injection piston (16, 18), first elastic means (20), adapted to stress the piston (16, 18) to cause the projection of the needle and the injection of the liquid contained in the reservoir, and second elastic means (22), adapted to return the reservoir (12) towards its retracted position. The second elastic means (22) have a force greater than that of the first elastic means (20). The injector further comprises means for automatically triggering the second elastic means (22) after injection. The second elastic means (22) are adapted to act at least partially between the injector body (10) and the piston (16, 18), when the reservoir (12) is returned.