Automatic injector

Abstract

An automatic injector for injecting one or more different injection liquids, comprising a combination of a substantially cylindrical means containing a discharge mechanism and a plurality of cartridge elements. The cartridge elements comprise a piston in the substantially cylindrical means, a sealing stopper, a number of separating stoppers equal to one less than the number of the liquids, and a needle holder with injection needle. The needle holder comprises a stopper that is movable in the substantially cylindrical means and comprises a longitudinal bore. The injector comprises a by-pass means for injection liquid in front of the sealing stopper. In another embodiment the injection comprises a combination of a discharge mechanism, a cartridge holder and a cartridge, the cartridge comprising a barrel including the plurality of cartridge elements, wherein the by-pass for injection liquid comprises at least one duct recessed in the wall of the shaft of the needle holder, the needle holder being connected to the barrel, at least one aperture being recessed in the front of the shaft of the needle holder. In yet another embodiment, the injector is suitable for accommodating a solid and solvent therefor, and for that purpose comprises a solvent by-pass means and a passable stopper between the solid and the solvent, in which the solvent can pass the passable stopper by a telescoping movement of external components of the injector and can reach the solid, as a result of which the injector is made ready for use.