Patent ID: 8313464

Claim:
An injection device comprising: a housing adapted to receive a syringe having an elongate syringe body terminating at a distal end in a discharge nozzle and at a proximal end in a flange, and having a bung that constrains a drug to be administered within the elongate syringe body distal of the bung, the elongate syringe body, discharge nozzle, flange and bung being coaxially aligned along a longitudinal axis, the housing including means for biasing the syringe from an extended position in which the discharge nozzle of the syringe extends from the housing to a retracted position in which the discharge nozzle is contained within the housing; a drive spring; a drive acted upon by the drive spring and in turn acting on the syringe to advance it from its retracted position to its extended position and discharge its contents through the discharge nozzle; a release mechanism, activated when the drive has been advanced to a nominal release position, to release the syringe from the action of the drive spring, whereupon the biasing means restores the syringe to its retracted position; and a locking mechanism that confines the returned syringe in its retracted position wherein: the housing includes a syringe carrier adapted to receive the syringe; the biasing means is adapted to bias the syringe carrier from an extended position to a retracted position; and the locking mechanism prevents the drive from retracting relative to the syringe carrier, thus confining the syringe between the drive and the syringe carrier.