| 摘要 |
<p>The invention relates to a fixed-shot retractable syringe (10) designed to limit the fluid amount sucked into the syringe to a maximal preset amount. According to the invention, the retractable syringe (10) comprises an oblong tube-shaped case (12) having a front end portion (18), a rear end portion (20) having an orifice (92) and a wall (22) which extends longitudinally between the front end portion (18) and the rear end portion (20), an oblong plunger (16) mounted to impart a reciprocating motion, in close sliding contact with the case wall (22) extending longitudinally, the plunger (16) having a tube-shaped wall (46) confining a front end portion (48) whose head (52) has a seal (60) of the plunger (16), an upper end portion (50) supporting a limiting cover (78) and a hollow inside part comprising a retraction cavity (72), a retractable needle (38) placed in the front end portion (18) of the tube-shaped case (12), preventing the syringe from being re-used after injection by retracting in the retraction cavity (72), a fluid chamber (44) placed in the tube-shaped case (12), between the retractable needle (38) and the head (52) of the plunger (16), the syringe also comprising a shot limiting structure (24, 62) preventing the plunger (16) from sucking more fluid than the maximal limited capacity of the syringe (10).</p> |
