Throwaway injection cartridge has bore to outlet chamber - and sealed by plug displaced by pump piston action to connect bore to chamber

摘要

Cartridge is intended for connecting (5) to the trocar of a cannula or to an injection needle. It comprises a cylindrical tube (1) containing the injection liquid, a piston (2) movable in the tube, a neck end (3) with cylindrical outlet bore (3'), and a plug (14) which fits in the bore to seal it. - The bore (3') leads to an outlet (6,5) chamber (4; 10) and means are provided to limit movement of the plug into the chamber and at the same time connect (e.g. 11) the bore to the chamber as the stop leaves the bore under the action of the liq. pressure. - These means may comprise a guide (8) with a cylindrical portion (8') and a conical portion (8'') converging to its open end and a lateral port (11) in the portion (8'), the plug having a conical top fitting in the portion (8'').