EP1979022A2 — Needle-free injection device and priming system

USPTO Abstract

Needle-free injection devices having a delivery system to effect an injection and a body configured to house the delivery system. The delivery system includes an injectate assembly adapted to house a volume of liquid and a drive assembly adapted to expel the volume of liquid from the injectate assembly. In some embodiments, the drive assembly includes a pair of parallel springs configured to simultaneously deliver a drive force to the injectate assembly. The device further includes a priming system adapted to prepare the device for delivery of an injection. The priming system includes a force-preparation assembly adapted to selectively arrange the drive assembly to provide the drive force to the injectate assembly. In some embodiments, the priming system includes a locking assembly adapted to releasably retain the injectate assembly relative to the body. In some embodiments, the priming system includes a dosing assembly adapted to selectively draw a volume of liquid into the injectate assembly.