| 摘要 |
<p>A safety syringe is formed of an inner sleeve receiving a cartridge with liquid, an outer sleeve through which said inner sleeve is telescopically reciprocated, and a plunger assembly that is attached to the inner sleeve and used to eject the liquid. The needle is mounted on a front end of the inner sleeve and in a retracted position is wholly contained within the outer sleeve while in a protracted position the needle is exposed so that it can be used for an injection. Advantageously, in one embodiment, the inner sleeves can rotate with respect to each other causing the needle to rotate both when the needle is extended and when is retracted into the outer sleeve. Another feature of the invention is that in one embodiment the inner sleeve has an internal puncture member for puncturing the cartridge. Therefore, instead of a dental needle with two sharp tips, a standard needle with a single tip and a Luer connection may be used.</p> |
