Retractable hypodermic needle

摘要

An automatically retractable hypodermic needle incorporating a spring loaded needle assembly held in place by a rotatable member having a dislodgable filler sleeve extending through a hole in the rotatable member, such that upon the application of downward pressure by the plunger on the edge of the rotatable member, the member is rotated and the dislodgable filler sleeve is aligned with the spring loaded needle assembly, allowing the needle assembly to force the filler sleeve out of the hole in the rotatable member, and accordingly, allow the filler sleeve and needle assembly to be automatically retracted into the barrel of the plunger.