Injection syringe for the missing and application of injection substances

Claim 1

A double chamber injection syringe for mixing and applying injection substances, comprising: a syringe cylinder; a first plunger displaceable therein and having a proximal end projecting from the cylinder and a stopper at a distal end engaging against an inner surface of said cylinder to form an injection volume in the syringe cylinder; a mixing plunger guided for movement in a longitudinal direction through said first plunger and projecting at a proximal end thereof from said stopper, said mixing plunger being provided at its distal end with a mixing piston having at least one opening through which injection substances can pass upon displacement of said mixing piston toward the injection volume; and a displaceable second stopper disposed between said mixing piston and one end of said syringe cylinder and separating a first chamber and a second chamber on opposite sides of said second stopper, said first chamber containing a substance to be dissolved or suspended, said second chamber containing a solvent or suspension agent, wherein said second stopper carries a valve responsive to advance of said mixing piston relative to said second stopper to provide communication between said chambers within the syringe cylinder, to enable transfer of said solvent or suspension agent to the first chamber by downward displacement of the second stopper in response to depression of the mixing piston.