| 摘要 |
A non re-usable syringe comprising a syringe barrel, a piston consisting of a piston head and a piston rod, a piston locking means being designed as claws and staple which locking means is activated during injection by relative approaching movement between the piston head and the piston rod in such a way as to lock the piston inside the syringe barrel against any subsequent aspiration or, alternatively, the locking means comprises radially expanding elastic claws being compressed together by a retaining ring so that during injection stroke the claws are released from the retaining ring. In both cases the claws come into engagement with the inner side wall of the syringe barrel to thereby inhibit retracting of the plunger. If forced retraction of the plunger is attempted in order to reload the syringe the locking means will perforate the syringe barrel due to sharpened ends of the claws. Also means to disrupt the piston seal by piercing and a non-separable connection between needle hub and syringe nozzle is disclosed. |
