| 摘要 |
A barrel adapter for a syringe having a barrel and plunger. The adapter comprises a barrel tip and a needle retraction mechanism having a needle subassembly with a needle and a lumen, actuator subassembly, and biasing member. The needle subassembly moves from an injection to a retracted position within the barrel tip. The actuator subassembly includes a retainer connected to the barrel tip, a stylet held in a stylet disc, and a prong passing into the retainer. The stylet slides within the needle lumen and is spaced from the needle tip in the injection position. The biasing member biases the NOM from the retainer. A locking arrangement compresses the biasing member when locked and releases the biasing member when actuated by depression of the plunger, which moves the prong against the retainer. The biasing member moves the needle and stylet from the injection position to the retracted position when released. |
| 主权项 |
1. A barrel adapter for a delivery syringe having a barrel and a plunger assembly adapted to move within the barrel, the barrel adapter comprising:
a barrel tip configured to be sealingly engaged with a distal end of the barrel; a needle retraction mechanism including:
a needle subassembly including a needle and a needle-over-mold through which the needle extends, the needle having a lumen, wherein the needle subassembly is disposed at least partially within the barrel tip and adapted to move from an injection position in which the needle extends from a distal end of the barrel tip to a retracted position,an actuator subassembly including a needle-over-mold retainer connected to the barrel tip, a stylet, a stylet disc holding a proximal end of the stylet, at least one prong passing through the stylet disc and into the needle-over-mold retainer, the at least one prong being actuable in response to movement of the plunger assembly within the barrel, wherein the stylet is axially slidable and at least partially disposed within the needle lumen and the stylet is proximally disposed and spaced from a distal tip of the needle when the needle is in the injection position, andat least one biasing member disposed between the needle-over-mold and the needle-over-mold retainer so as to bias the needle-over-mold away from the needle-over-mold retainer; and an actuable locking arrangement disposed to maintain the at least one biasing member in an energized position when the locking arrangement is locked and release the biasing member when actuated by the actuator subassembly, the locking arrangement being actuable by depression of the plunger assembly to move the at least one prong against the needle-over-mold retainer, the at least one biasing member being disposed to provide relative motion of the needle and stylet from the injection position to the retracted position when the biasing member is released from the energized position. |
