| 摘要 |
A single-use syringe having a needle which retracts upon a full depression of its plunger and thus, renders the syringe non-reusable. The plunger selectively engages the barrel of the syringe so as to limit the withdraw of the plunger relative to the barrel. The barrel has formations extending therefrom which selectively and matingly engage formations extending from the plunger so as to selectively limit the travel of the plunger relative to the needle and retract the needle into a concealed position. The nose of the barrel carries a split ring which is contractible to permit a rearward displacement of the barrel and the needle attached thereto relative to the stationary housing upon a full depression of the plunger. The travel of the barrel relative to the stationary body is terminated by dogs located proximate the forward end of the nose which are engageable with the notches in the stationary housing upon the rearward displacement of the barrel relative to the stationary housing. A cap may be provided for sheathing the needle prior to use. |
