Abstract: A retracting needle assembly for use with a syringe barrel having a cylindrical collar and a plunger having a release element with a sharp distal end includes an outer hub having a passageway therethrough and an inner hub having a proximal end, a distal end and a conduit therethrough. The proximal end of the inner hub has an inner portion and a dissociable outer portion connected to the inner portion. The dissociable outer portion is further connected to the outer hub. The distal end of the inner hub is smaller than the passageway of the outer hub at the distal end of the outer hub and projects distally outwardly therefrom. A needle cannula having a distal end, a proximal end, and a lumen therethrough is connected to the inner hub so that the lumen is in fluid communication with the conduit. An energized spring is contained between the inner and outer hub. Structure is provided for connecting the outer hub to the collar of the syringe barrel.

Abstract: A retracting needle assembly for use with a syringe barrel having a cylindrical collar and a plunger having a release element with a sharp distal end includes an outer hub having a passageway therethrough and an inner hub having a proximal end, a distal end and a conduit therethrough. The proximal end of the inner hub has an inner portion and a dissociable outer portion connected to the inner portion. The dissociable outer portion is further connected to the outer hub. The distal end of the inner hub is smaller than the W o passageway of the outer hub at the distal end of the outer hub and projects distally outwardly therefrom. A needle cannula having a distal end, a proximal end, and a lumen therethrough is connected to the inner hub so that the lumen is in fluid communication with the conduit. An energized spring is contained between the inner and outer hub. Structure is provided for connecting the outer hub to the collar of the syringe barrel.

Abstract: An improved syringe plunger rod for a retracting needle syringe is illustrated having a plunger rod with inner and outer members and a retaining ring. The retaining ring restricts movement between the inner and outer members until the ring makes contact with the proximal end of the retracting needle syringe and further distal force is applied to the inner member. Once disengaged, the inner member moves relative to the outer member to activate the retractable needle syringe. One advantage of the improved plunger rod is that it reduces the probability of premature activation of the retractable needle syringe. In addition, the improved plunger rod assists in the prevention of re-use of the syringe.

Abstract: A retracting needle syringe is described which allows safe and easy disposal of a syringe and prevents re-use of the syringe by destroying the plunger rod and needle hub and retracting the needle into the plunger rod. Once the safety feature is activated, positive or negative pressure in the barrel to draw out medication is defeated. The retracting needle safety feature requires only an increase of force along the same line of action as the injection stroke. This allows for safe, one-handed injection, which is critical in some situations. The retracting needle syringe of the present invention also minimizes the amount of wasted medication because the plunger rod incorporates a plunger tip that occupies the entire volume inside the barrel. Because the retracting needle syringe uses standard luer-lok fittings, it can be used with a variety of standard needles that do not have retracting cannula.