| 摘要 |
A safety syringe for intravenous injection includes: a hollow needle normally eccentrically held in a sleeve portion formed on a front portion of a syringe, a suction tube replaceably mounted on the sleeve portion for sucking liquid medicine from an ampoule into the syringe, a plunger straightly slidably held in the syringe for injection use, a coupling member retained in the plunger engageable with a biasing socket recessed in a rear needle portion of the hollow needle with the biasing socket, whereby upon pushing of the plunger to the needle by forcibly inserting the coupling member into the biasing socket of the needle when finishing the injection, the biasing socket will be forcibly coupled with the coupling member, and upon retraction of the plunger and the needle into the syringe, the needle will be automatically inclined to prevent an outward protruding of the retracted needle from the syringe for preventing its pricking to the others; with the hollow needle annularly formed with a ratchet-tooth recess in a shank portion of the hollow needle to be engaged with a ratchet tooth annularly formed in an inside surface of the sleeve portion, thereby preventing an outward forward ejection of the hollow needle during the injection, and allowing a smooth rearward releasing of the hollow needle from the sleeve portion to be retracted into the syringe after the injection. |
