| abstract |
An automatic injector comprising an elongated housing assembly having a forward end, a stressed spring assembly mounted within the rearward end of the housing assembly so as to be released in response to a predetermined manual actuation procedure, and a medicament injection cartridge assembly mounted within the forward end of the housing assembly in cooperating relation with the stressed spring assembly. The improvement of the present invention is in the medicament injection cartridge assembly which includes a medicament container, a hypodermic needle disposed forwardly of the container mounted in a sterile condition within the housing assembly adjacent the forward end thereof. A forward seal is provided for sealing the forward end of the container from the hypodermic needle. A rearward piston is mounted in the rearward end of the container for forward movement therein in slidably sealed relation thereto. A plurality of individual dosages of different relatively incompatible liquid medicaments is disposed within the container between the forward seal and the piston separated by a movable interior seal within the interior of the container between the piston and the forward seal. The improved arrangement is operable in response to the manual accomplishment of the manual actuating procedure and the resultant release of the stressed spring assembly to move the hypodermic needle forwardly and outwardly of the housing assembly into the muscle tissue of a patient and the piston forwardly into the container so that the plurality of individual dosages therein is moved forwardly out of sealed relation with respect to the forward and interior seal outwardly through the needle into the muscle tissue of the patient. |