PREFILLED RETRACTABLE SYRINGE, PLUNGER AND NEEDLE ASSEMBLY THEREFOR

摘要

A RETRACTABLE SYRINGE (10), PLUNGER (20) AND RELEASABLE NEEDLE RETAINING ASSEMBLY (90) ARE PROVIDED. THE RETRACTABLE SYRINGE (10) TYPICALLY HAS A GLASS BARREL (11) AND IS PREFILLED WITH FLUID CONTENTS BEFORE USE. THE RELEASABLE NEEDLE RETAINING SYSTEM (90) COMPRISES A RETRACTABLE NEEDLE (40), A NEEDLE SEAL (43), A RETAINING MEMBER (30) AND AN EJECTOR MEMBER (60) THAT IS OPERABLE TO RELEASE THE RETRACTABLE NEEDLE (40) FROM THE RETAINING MEMBER (30). THE RETAINING MEMBER (30) HAS A MATING SURFACE FOR MOUNTING TO A COMPLEMENTARY MATING SURFACE OF AN INTERIOR WALL OF A SYRINGE BARREL (11). THE PLUNGER (20) COMPRISES A PLUNGER OUTER (22), A PLUNGER ROD (21) FRANGIBLY CONNECTED TO A CONTROLLING MEMBER (50), A SPRING (70) AND A UNITARY PLUNGER SEAL CAPABLE OF ENGAGING THE RETRACTABLE NEEDLE (40), WHEREIN THE PLUNGER ROD (21), PLUNGER OUTER (22) AND THE CONTROLLING MEMBER (50) CO-OPERATE TO RELEASABLY MAINTAIN THE SPRING (70) IN AN INITIALLY COMPRESSED STATE. AFTER DELIVERY OF FLUID CONTENTS OF THE SYRINGE, THE PLUNGER (20) FORCES THE EJECTOR MEMBER (60) TO RELEASE THE RETRACTABLE NEEDLE (40) FROM THE RETAINING MEMBER (30). DECOMPRESSION OF THE SPRING (70) AT THE END OF DEPRESSION OF THE PLUNGER (20) FACILITATES RETRACTION OF THE RETRACTABLE NEEDLE (40) WHEN ENGAGED WITH THE UNITARY PLUNGER SEAL. DUAL LOCKING SYSTEMS PREVENT RE-USE OF THE SYRINGE AFTER NEEDLE RETRACTION.