Patent ID: 6669671
Filing Date: 2003-12-30
Classification: A61B,A61M

Abstract:
A retractable syringe needle for use with a syringe, said syringe comprising a plunger and a tubular syringe barrel having a defined outer diameter, said barrel having an open end adapted to receive the plunger and a closed end having a tip projecting therefrom, said tip having a maximum defined diameter which is less than the defined outer diameter of the syringe barrel and a longitudinal bore passing through the tip and the closed end of the barrel, said retractable syringe needle comprising:a) a needle assembly featuring: a needle-holding mechanism, said needle-holding mechanism comprising a hub and an annular sleeve connected with said hub, said sleeve having an exterior surface and an interior surface, where said interior surface of said sleeve defines a cavity having a diameter which is substantially equal to the maximum defined diameter of the tip of the syringe barrel, the interior surface of the sleeve being adapted to frictionally engage the tip of the syringe barrel; a hypodermic needle extending through said hub; and a pin directly connected to the exterior surface of said annular sleeve; b) a container with a defined cylindrical axis having a tubular wall with a longitudinal slot therein, said container having a first open end adapted to receive a syringe barrel and a second open end adapted to receive a syringe needle, said container having said needle assembly mounted therein so that the pin is slidably engaged by the longitudinal slot, and so that said needle assembly may be moved from a first position where the needle is within the container to a second position where the needle is exposed by sliding the pin toward the second open end of the container and causing the needle to pass through the second open end; c) a means for biasing the needle assembly toward said first position; and d) a means for releasably engaging the pin at a defined location in said longitudinal slot so as to hold said needle assembly in said second position; wherein said means for releasably engaging the pin comprises a notch which intersects said longitudinal slot at said defined location, so that said needle assembly may be releasably held in said second position by sliding said pin out of said longitudinal slot into said notch; wherein the hub of said needle-holding mechanism is movably positioned along the defined cylindrical axis of the container, the position of the hub being maintained along the axis by a crosspiece rigidly fixed to a defined location along the length of the pin, said crosspiece being on the exterior of the container, and being unable to pass through the longitudinal slot.