| 摘要 |
<p>A plunger for use in a retractable-type safe self-destructing syringe, comprising a plunger body (1). An asymmetric flexible locking retracting piece is arranged at an end part of the plunger body (1). The retracting piece uses the symmetric centerline of the plunger as the axis, and forms one engaging-locking part on each of the two sides of the axis, where the engaging-locking parts are asymmetric. The engaging-locking part of one side or the engaging-locking parts of both sides are provided with flexibility, thus ensuring that the retracting piece is allowed to enter smoothly into a cavity of the needle base and to engage with and lock onto the engaging part in the cavity of the needle base. When the needle base is retracted into a barrel body of the syringe, under the effect of an asymmetric force, the needle base automatically deflects to a side, while an injection needle therefore swings to a side of the inner wall of the barrel body and is locked by a neck part of the barrel body, thus effectively preventing secondary injury or cross-infection caused by the needle being pushed out again after being used.</p> |
