Abstract: A needle-stick safety syringe includes an inner tubular body, plunger, and needle extending from a distal end of said inner tubular body, an outer tubular housing concentrically and slidingly surrounding at least a portion of the inner tubular body and biased apart from the inner tubular body. A recess is defined within an interior wall surface of the outer tubular housing, and a latch attached to a distal end of the inner tubular body. The latch includes a ring-shaped collar attached to the distal end of the inner tubular body and includes a cantilevered push-stop. A portion of the cantilevered push-stop is sized to fit within the recess when the latch is sufficiently disposed within the outer tubular housing.

Abstract: A needle stick safety syringe includes a outer tubular protective cover or sleeve for the inner syringe body where a concentric coil spring is compressed against the normal flange of the inner syringe body and retained there by a stop which is cantilevered from a collar affixed to the distal end of the inner syringe body. This cantilevered stop also includes a convenient button which may be easily depressed by a finger of one hand holding the outer tubular body to allow the sleeve to be slid over the needle under the bias of the spring. The cantilevered button and stop rides in a groove in the inner diameter of the tubular outer protective body and is captured by a slot which effectively prevents reuse.