TW200702009A - Improved controlled retraction syringe and plunger therefor - Google Patents

Abstract

A retractable syringe and plunger therefore are provided, the syringe having a barrel, a retractable needle mount to which is mounted or is mountable a needle, and a plunger, the plunger comprising an initially compressed spring, a means for engaging the retractable needle mount, an integrally formed plunger seal and a removable controlling means for facilitating control of the rate of retraction of the retractable needle mount when engaged with the plunger. The needle mount is held in the barrel by a holding means which prevents inadvertent retraction of the needle mount when the plunger is withdrawn to fill the syringe. The holding means comprises a plurality of clips that may be integrally formed with the barrel or may be present on a cap mounted to the barrel. An ejector means is also provided, whereby plunger depression can urge the ejector means to release the needle mount from the holding means and thereby allow retraction of the needle mount following decompression of the spring.