Abstract: A multiple use needle-less hypodermic injection device for individual users comprising of a light weight, pocket sized, spring powered unit, and a multiple use, low cost, easily replaceable thermoplastic injection head. The present invention targets the single-patient-self-injection applications, such as insulin users, when risks of cross contamination between different patients are not present, therefore not requiring the parts containing the medicament dose, or the parts in contact with the delivery of the medicament dose, to be necessarily disposed and replaced after each injection.

Abstract: A needleless, low pressure, air powered medicine injector with a quick disconnect medicine delivery assembly removably connected to the injector housing. Low pressure air drives a biased piston through a discharge stroke, beginning from the retracted position into the medicine chamber, thereby forcing medicine through a one-piece nozzle. A removable chamber filling mechanism connected to the housing is coupled to the medicine chamber through fill ports, such that the medicine chamber is filled utilizing a positive pressure medicine distributor. A movable spacer collar positioned in front of the nozzle provides an air gap between a patient's skin and the one-piece nozzle. A safety interlock coupled to an activating mechanism and the chamber filling mechanism prevents unwanted discharge of the injection.