| 摘要 |
PCT No. PCT/AU91/00558 Sec. 371 Date Jun. 21, 1993 Sec. 102(e) Date Jun. 21, 1993 PCT Filed Nov. 29, 1991 PCT Pub. No. WO92/09320 PCT Pub. Date Jun. 11, 1992.A syringe unit arranged for a single-use only. The syringe unit comprises a barrel substantially closed at one end by a nozzle and open at the other end. A plunger having a piston is received in the barrel and is movable therealong. A fluid chamber is defined within the barrel between the piston and the nozzle. A syringe needle is releasably secured to the barrel with the cannula extending outwardly from the barrel and communicating with the fluid chamber and is releasable upon rotation relative to the barrel. An engaging means is provided for releasably engaging the piston with the needle whereby when so engaged the piston can be rotated to effect release of the needle from the barrel and then retracted to move the needle into a protective position within the barrel. The engaging means comprises a socket defined in a cavity provided in the needle, and a projection provided on the piston for reception in the socket and engagement therewith. The cavity provides for fluid communication between the barrel and the cannula of the needle and at least one fluid flow passage is defined between the cavity and the projection when the projection is engaged in the cavity. The fluid flow passage contributes to provision of fluid communication between the fluid chamber and the bore of the cannula. |
