AUTOINJECTOR HAVING A TRIGGER AND A COCKING ARRANGEMENT WITH AN ELONGATE FLEXIBLE ELEMENT

摘要

An autoinjector device comprises a drive housing (10) and a syringe housing (12) which can be disconnected to allow insertion of a syringe. A drive mechanism in the drive housing is cocked by means of a cord (8) connected between the drive housing and the syringe housing. The drive mechanism comprises a drive gear (22) rotatably mounted in the drive housing and acting as a rotary crank connected by a connecting rod (26) to a plunger (28). In use the drive gear (22) is driven by a torsion spring (35) so that the drive mechanism extends the syringe from the syringe housing and expels a dose and then retracts the syringe back into the housing. A firing button (14) releases the drive gear to be driven by the torsion spring but is also engageable as a brake on the rim of the drive gear.