| 摘要 |
PROBLEM TO BE SOLVED: To prevent undesired action of a safety stop bush button by a method wherein when a working latch member engages a needle hub, a protruding part arranged on a working latch member adjoins a catheter hub to prevent the working latch member from being pressed in. SOLUTION: When a working latch member 34 is lifted up to an unworking position, a smaller hole of a keyhole-shaped opening 36 communicates with a lumen of a barrel 31. At this position, the smaller hole part engages a needle hub 3 while the needle hub 33 adjacent to the extreme end of the barrel 31 is held against a spring 39. When the working latch member 34 is at the non- working position, the protruding part 40 is arranged inside a catheter hub 22 and a catheter 22 is on a needle 32. Thus, the protruding part 40 prevents the working latch member 34 from moving downward to the working position when the catheter 22 adjoins the extreme end of the barrel 31. |
