Automatic medicament injector employing non-coring needle

A fluid injector comprising:

• (A) a tubular cartridge having an upper end and a lower end, said cartridge having an interior bore which widens at said lower end of said cartridge to form a needle housing assembly residence chamber for receiving a needle housing assembly;
• (B) a puncturable end cap sealing said lower end of said cartridge;
• (C) an ampule slidably disposed within the upper end of said cartridge bore, said ampule having an upper end and a lower end and being suitable for storing a fluid charge to be expelled therefrom;
• (D) a piston slidably seated within said upper end of said ampule;
• (E) a puncturable ampule end stopper rigidly attached to and sealing said lower end of said ampule;
• (F) a needle housing assembly slidably disposed within said upper end of said cartridge below said ampule, said needle housing assembly comprising:
• a generally cup-shaped housing having a housing bottom and flexible upstanding housing wall sections attached to the periphery of said housing bottom, said housing walls, extending toward said lower end of said ampule and said housing wall sections having upper edges for engaging with said lower end of said ampule,
• a hollow injection needle extending through and rigidly engaged by said housing bottom and having an internal section, and an external section, said internal section of said hollow injection needle extending from said housing bottom, upwardly within said housing walls, toward said puncturable ampule end stopper, and said external section of said hollow injection needle extending from said housing bottom downwardly toward said puncturable end cap of said cartridge without protruding from said puncturable end cap,
• the upper edges of said housing wall sections being engageable with said lower end of said ampule as said ampule slides downwardly within said cartridge bore, whereby actuation moves said ampule downwardly within said cartridge bore in said upper end of said cartridge toward said lower end of said cartridge thus engaging said upper edges of said housing wall sections and moving said needle housing assembly from said upper end of said cartridge into said needle housing assembly residence chamber at said lower end of said cartridge causing said external section of said hollow injection needle to protrude through said puncturable end cap and allowing said flexible housing wall sections to expand outwardly in said needle housing assembly residence chamber, the further downward movement of said ampule causing the internal section of said hollow injection needle to pass through said puncturable ampule end stopper thereby allowing fluid to be injected outwardly through said hollow injection needle;
• and
• (G) an actuator for engaging said tubular cartridge and for propelling said ampule toward said puncturable end cap and for propelling said piston within said ampule toward said ampule end stopper to inject a fluid.