| 摘要 |
The present invention relates to a self destructing syringe which is only capable of being used once and is thereafter rendered useless. The syringe has a plunger and plunger rod which are interconnected by a coupling assembly. This coupling assembly includes a receiver which is hollow and extends outwardly from the plunger and a connector which is in the form of an enlarged head on the end of the plunger rod which is adapted to be inserted into the receiver. In the preferred embodiment, the receiver has longitudinal splits along the side wall which form outwardly biased fingers. The coupling assembly also includes a locking sleeve which is adapted to slide over the receiver to prevent the connector from being released from the receiver when the locking sleeve is in place. The locking sleeve remains in place as the plunger rod is pulled away from the needle to draw fluid into the syringe and moves away from the receiver as the plunger rod is pushed toward the needle to discharge the fluid from the syringe. The locking sleeve frictionally engages the inner wall of the housing and is wedged against the housing when the plunger rod is pushed towards the needle. Simultaneously, the fingers spring outwardly against the inner wall of the housing. Thereafter, there is nothing to hold the plunger rod is the receiver and if the needle is attempted to be used again, the plunger rod is released from the syringe rendering the syringe useless. |
