Needle sheath assembly

A hypodermic syringe assembly comprising a barrel having an open proximal end, a chamber for retaining fluid and a tip portion extending from a distal end of said barrel having a passageway therethrough communicating with said chamber;

• a needle cannula having a distal end extending outwardly from said tip portion including a lumen therethrough in fluid communication with said passageway;
• a needle shield assembly including a resilient needle sheath having an open proximal end, a closed distal end, a sidewall defining a receptacle therein, said resilient needle sheath being positioned within an elongate rigid needle shield having an open proximal end;
• a distal end and a sidewall therebetween;
• means for holding said sheath within said shield so that said sheath cannot be removed from said shield during normal use of said syringe assembly, said sheath including cannula sealing means at said distal end of said receptacle;
• said needle shield assembly being positioned with said distal end of said cannula engaging said cannula sealing means and said proximal end of said needle sheath removably engaging said tip portion to hold said shield assembly on said barrel while simultaneously sealing said lumen of said cannula so that said sheath surrounds the entire portion of said cannula which extends outwardly from said tip portion.

A hypodermic syringe assembly comprising an elongate barrel having an open proximal end, a chamber for retaining fluid and a tip portion extending from a distal end of said barrel having a passageway therethrough communicating with said chamber;

• a needle cannula having a distal end extending outwardly from said tip portion including a lumen therethrough in fluid communication with said passageway;
• a needle shield assembly including a resilient needle sheath having an open proximal end, a closed distal end, a sidewall defining a receptacle therein, a projection extending outwardly from said proximal end, said resilient needle sheath being positioned within an elongate rigid shield having an open proximal end, a distal end and a sidewall therebetween;
• means for holding said sheath within said shield so that said sheath cannot be removed from said shield during normal use of said syringe assembly, said holding means including a first inwardly projecting ledge in said shield positioned proximally of said sheath projection;
• said sheath including cannula sealing means at said distal end of said receptacle for providing a fluid-tight seal between said lumen and the environment of said syringe assembly including an elongate retention conduit having a sidewall adapted to accept said distal end of said cannula in fluid-tight engagement between the outside of said cannula and said conduit sidewall;
• said needle shield assembly being positioned with said distal end of said cannula engaging said cannula sealing means and said proximal end of said sheath removably engaging said tip portion to hold said needle shield assembly on said barrel while simultaneously sealing said lumen of said cannula so that said sheath surrounds the entire portion of said cannula which extends outwardly from said tip portion, said shield and said sheath being structured so that said shield cannot be manually assembled to or manually separated from said sheath while said sheath is properly positioned sealing said cannula and engaging said tip portion of said barrel;
• said needle shield assembly being easily engageable to and removable from said barrel and said cannula using manual force applied to said shield;
• a stopper slidably positioned in fluid-tight engagement inside said barrel adapted to engage a plunger rod to facilitate its operation, 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;
• and medicament within said chamber between said stopper and said distal end of said barrel.

A needle shield assembly for use with a syringe barrel having a chamber for retaining fluid, a tip portion extending outwardly from a distal end of said barrel having a passageway therethrough and a needle having a distal end extending outwardly from said tip portion having a lumen therethrough in fluid communication with said passageway comprising:

• a resilient needle sheath having an open proximal end, a closed distal end, a sidewall defining a receptacle therein, and a projection extending outwardly from said proximal end;
• said resilient needle sheath being positioned within an elongate rigid shield having an open proximal end, a closed distal end and a sidewall therebetween;
• means for holding said sheath within said shield so that said sheath cannot be removed from said shield during normal use of said syringe assembly including a first inwardly projecting ledge in said shield, positioned proximally of said sheath projection;
• said sheath including cannula sealing means at said distal end of said receptacle for providing a fluid-tight seal between said lumen and the environment of said syringe assembly;
• said needle shield assembly being sized so that said distal end of said cannula sealing means is adapted to engage said cannula and said proximal end of said sheath is adapted to removably engage said tip portion to hold said shield assembly on said barrel while simultaneously sealing said lumen of said cannula so that said sheath may surround the entire portion of said cannula which extends outwardly from said tip portion;
• said shield and said sheath being structured so that said shield cannot be manually assembled to or manually separated from said sheath while said sheath is properly positioned sealing said cannula and engaging said tip portion of said barrel;
• and
• said needle shield assembly being easily engageable to and removable from said barrel and said cannula using manual force.