Multiple compartment hypodermic devices

Claim 1

A multichamber hypodermic ampoule comprising a first cylinder; a first diaphragm sealed to and closing one end of said first cylinder; a plunger slidably disposed in the other end of the first cylinder to provide a first chamber between said plunger and said first diaphragm; said plunger comprising a cylindrical plug having a first cylindrical portion which comprises means to effect a substantially liquid-tight seal with said first cylinder, and having a second cylindrical portion which comprises means engaging said first cylinder, and means providing at least one passageway along an axial extent of said second cylindrical portion; a hypodermic needle disposed in said first chamber for movement with said plunger toward said first diaphragm and having an open end adjacent said plunger and an opposite pointed discharge end adjacent said first diaphragm; a powdered medicament in said first chamber; a second cylinder axially aligned with said first cylinder and having one end closed by insertion of said first diaphragm therein with a peripheral portion of the first diaphragm in axial alignment with the inner surface thereof; a second diaphragm closing the other end of said second cylinder; said first and second diaphragms and second cylinder, together, defining a second chamber; and a fluid medicament in said second chamber; whereby said fluid and solid medicaments may be mixed preparatory to making an injection by first moving said plunger and needle sufficiently toward said first diaphragm to project the pointed end of the needle through said first diaphragm to establish communication between the two chambers and by then moving said first cylinder, first diaphragm, plunger, and needle as a unit toward said second diaphragm to progressively reduce the volume of said second chamber substantially to zero and thereby express said liquid medicament through the neeDle into the first chamber while bringing said first and second diaphragms substantially into engagement and disposing the pointed end of said needle in position to project said needle through said second diaphragm upon further movement of said plunger toward said first and second diaphragms.