| 摘要 |
A jet injector having cartridge and power pack assemblies is disclosed. In one embodiment, the cartridge assembly includes a tube containing the medicament with a plunger at one end and a stopper at the other end. The plunger is movable within the tube lumen to force the stopper against a needle, thereby creating a fluid pathway through the stopper. In another embodiment, only the plunger is movable within the tube lumen and the stopper, which can be integral to the rest of the cartridge assembly or a separate component, already has a pathway for ejection of the medicament. The present invention also relates to an energy mechanism for the power pack assembly that is a gas spring containing a charging material existing in liquid and gaseous phase equilibrium within the gas spring to maintain a substantially constant pressure prior to activation. |
