| 摘要 |
A retractable needle medical assembly includes a barrel and a plunger assembly defining an internal passageway. A sleeve is mounted to the barrel and extends into the internal passageway defined by the plunger assembly. An actuator member, in the form of an actuator tube, is mounted within the sleeve toward its rearward end, and includes a trigger which can either be manually engaged by the user or engaged by the plunger when the plunger is in its full-forward position relative to the barrel. A hub is received within the sleeve passage, and a spring bears against the hub so as to urge the hub to a rearward, retracted position. The actuator tube engages the hub so as to maintain the hub in a forward position, and a needle assembly consisting of a needle and a head is engaged with the hub by the user prior to operation of the assembly. Depression of the trigger results in movement of the actuator tube to disengage the actuator tube from the hub, so as to allow the spring to propel the hub, and thereby the needle assembly, rearwardly to retract the needle into the sleeve passage and to prevent accidental contact therewith. The needle retraction system may be incorporated into a medical device such as a syringe, or into a system for collecting blood or other body fluids from a patient. |
