Dispenser for storing and mixing several components

Claim 1

A two compartment syringe assembly for dispensing a liquid medication derived from the mixing of a first and a second component, one of said components being a liquid, said assembly having a cylindrical medication barrel having a forward medication delivery end and a rearward end, an axially slidable plunger for closing off the rearward end of said barrel, said plunger being disposed in fluid tight engagement in said barrel, a partitioning stopper being separate from the plunger for dividing the barrel into said two compartments, said stopper being slidably disposed in fluid tight engagement in said barrel, said stopper having a fluid passageway extending axially therethrough, a pop-out blow plug disposed in fluid tight engagement in said fluid passageway, said blow plug being displaceable, so as to unblock said fluid passage, under fluid pressure, as induced by movement of the plunger, said partitioning stopper being forwardly displaceable by abutting contact with said plunger as said plunger undergoes forward movement, characterized in that said stopper is of a resilient material, said fluid passageway consists of a first rearward opening and a second forward opening connected to and spaced apart by a fluid bypass chamber, said bypass chamber having a forward axial end wall and a rearward axial end wall, said first opening being defined by said rearward axial end wall and said second opening being defined by said forward axial end wall, said pop-out blow plug is sized larger than said first and second openings and smaller than said bypass chamber, and said pop-out blow plug releasably blocks one of said first and second openings, the opening blocked by the blow plug being defined by a respective resilient axial end wall such that, under said pressure, the end wall deflects into said bypass chamber and said blow plug is dislodged from said opening into the fluid bypass chamber thereby allowing for bypass flow of liquid from one compartment through the partition stopper and into the other compartment.