Patent ID: 8535266
Filing Date: 2013-09-17
Classification: A61M

Abstract:
1. A retractable safety syringe apparatus, comprising: a syringe body having a distal end, a proximal end and an inner surface; a plunger having a piston slideably disposed within the syringe body and a shaft extending through the proximal end; a distal seal disposed between the plunger piston and the syringe body forming a fluid tight seal between the plunger piston and the syringe body; a needle holder disposable at the distal end of the syringe body, the needle holder being removeably engageable to the distal end of the syringe body, the needle holder also being engageable to the piston and removeably engageable from inside the syringe body; a release element disposed between the needle holder and the syringe body, the release element configured to removeably engage the needle holder to the distal end of the syringe body at least prior to and during the use of the syringe and at least until the release element is engaged by the plunger, the release element frictionally engaged to the needle holder and defining a retaining force holding the needle holder at the distal end of the syringe body at least prior to and during the use of the syringe and at least until the release element is engaged by the plunger, the needle holder configured to be released from removable engagement with the syringe distal end of the syringe body by the engagement of the plunger with the release element; and an adapter releaseably engageable to the distal end of the syringe body from outside the syringe body, the needle holder being removeably engageable from outside the syringe body to the distal end of the syringe body via the adapter, so that the adapter can be removed by a user from outside the syringe body to change needle holders prior to use of the syringe, wherein the piston is biased toward a retracted position via a retraction force greater than the retaining force so that the needle holder is withdrawn into the syringe body responsive to the engagement of the piston with the needle holder.