Two-component medication syringe assembly

A two-component syringe assembly comprising:

• an elongate barrel having a chamber for retaining fluid;
• a distal end of said barrel having a passageway therethrough communicating with said chamber;
• a bypass stopper slidably positioned in fluid-tight engagement inside said barrel;
• a bypass means defining a bypass zone positioned along said barrel for allowing fluid to flow around said bypass stopper when said bypass stopper is positioned intermediate the ends of said barrel in said bypass zone;
• a bypass stopper extension projecting outwardly from the distal end of said bypass stopper, said extension including a distal extension rib contacting the inside of said barrel and a recess between said extension rib and said bypass stopper, said extension rib including a groove for allowing fluid communication between said recess and said chamber, said groove positioned angularly with respect to the longitudinal axis of said barrel so that fluid passing through said groove is directed angularly with respect to the longitudinal axis of said barrel;
• a stopper slidably positioned in fluid-tight engagement inside said barrel;
• a rigid plunger rod having an elongate body portion engaging said stopper to facilitate operation of said stopper, said body portion extending outwardly from the proximal end of said barrel;
• and
• a barrier means positioned on said body portion and intermediate the ends thereof, said barrier means projecting outwardly from said body portion into the space between the inside wall of said barrel and the outside of said body portion for acting as a barrier for blocking the path of fluid which may be propelled in a distal direction through said bypass while said syringe is being operated, said barrier means being positioned on said body portion so that said barrier means is within said chamber when said stopper is positioned within said bypass zone, wherein the area described by said barrier means as viewed along the longitudinal axis of said plunger rod being at least about 87 percent as large as the area described by the interior wall of said barrel as viewed along the longitudinal axis of said barrel.

A two-component medication syringe assembly comprising:

• an elongate substantially cylindrical barrel having an interior wall defining a chamber for retaining fluid;
• a tip extending from a distal end of said barrel having passageway therethrough communicating with said chamber;
• closure means releasably connected to said tip for sealing said passageway;
• a bypass stopper slidably positioned in fluid-tight engagement inside said barrel;
• a raised peripheral portion of said barrel serving as a bypass and defining a bypass zone, said bypass zone being longer along the longitudinal axis of said barrel than the length of said bypass stopper along the longitudinal axis of said barrel, said bypass being raised enough to allow fluid flow around said bypass stopper when said bypass stopper is positioned within said bypass zone;
• a bypass stopper extension projecting outwardly from the distal end of said bypass stopper, said extension including a distal extension rib contacting said interior wall of said barrel and a recess between said extension rib and said bypass stopper, said extension rib including a groove for allowing fluid communication between said recess and said chamber, said groove positioned angularly with respect to the longitudinal axis of said barrel so that fluid passing through said groove is directed angularly with respect to the longitudinal axis of said barrel;
• a stopper slidably positioned in fluid-tight engagement inside said barrel, said stopper being positioned further from said distal end than said bypass stopper, said stopper capable of moving fluid from said chamber through said passageway upon its movement toward said distal end, said stopper capable of facilitating the drawing of fluid into said chamber through said passageway upon its movement away from said distal end;
• a rigid plunger rod having an elongate body portion engaging said stopper to facilitate operation of said stopper, said body portion extending outwardly from the proximal end of said barrel;
• and
• a plunger rod barrier flange positioned transversely with respect to the longitudinal axis of said body portion of said plunger rod and intermediate the ends thereof, said barrier flange projecting outwardly from said body portion into the space between the inside of said barrel and the outside of said bydo portion wherein the area described by the periphery of said barrier flange as viewed along the longitudinal axis of said plunger rod being at least about 87 percent as large as the area described by the interior wall of said barrel as viewed along the longitudinal axis of said barrel, said barrier flange acting as a barrier for blocking the path of fluid which may be propelled in a distal direction through the bypass while said syringe is being operated, said barrier flange being positioned on said body portion so that said barrier flange is within said chamber when said stopper is positioned in said bypass zone;
• a first component of liquid medication contained within said chamber between said bypass stopper and said stopper, said bypass stopper being positioned outside said bypass zone adjacent to the proximal end of said bypass;
• and
• a second component of medication substantially within said chamber between said bypass stopper and said distal end of said barrel.