AUTOMATIC INJECTION AND RETRACTION DEVICES FOR USE WITH PRE-FILLED SYRINGE CARTRIDGES

摘要

An automatic injection and retraction device having a longitudinal axis is provided that includes an injection assembly, a retraction assembly, and a pre- filled syringe cartridge. The injection assembly has an activation-prevention feature moveable between an on position and an off position. The retraction assembly has a needle guard that is removable in a direction along the longitudinal axis upon application of a removal force. The pre-filled syringe cartridge has a hypodermic needle with a needle sheath thereon. The retraction and injection assemblies are secured to one another so that the pre-filled syringe cartridge is in the retraction assembly with the needle sheath secured to the needle guard. The retraction and injection assemblies are configured so that, upon application of a twisting torque to the injection and retraction assemblies, the activation-prevention feature moves from the on position to the off position simultaneous with applying the removal force to the needle guard.