| 摘要 |
PROBLEM TO BE SOLVED: To provide an indwelling canula assembly which obviates liquid leakage by deterioration with lapse of time and a valve plug. SOLUTION: This indwelling canula assembly 1 has a hollow outer needle 2, an outer needle hub 3 which is disposed at the base end of the outer needle 2 and has an internal cavity part 34 communicating with the inside of the outer needle 2, an inner needle 4 which is inserted into the outer needle 2, an inner needle hub 5 which is disposed at the base end of the inner needle 4 and a valve plug 7 which consists of an elastic membrane installed so as to seal the internal cavity part 34 of the outer needle hub 3 in the internal cavity part 34. The valve plug 7 has a nearly funnel shape over the entire part and has a projecting part 72 of a shape converging toward the front end. A hole 73 to be inserted with the inner needle 4 is formed at the center of the projecting part 72. When the inner needle 4 is removed by moving the same toward the base end, the projecting part 72 which is thus far projected toward the front end is inverted upside down and is projected toward the base end in accordance with the same. The projecting part 72 before the inversion comes into tight contact with the outer peripheral surface of the inner needle 4, thus maintaining the liquid tightness. Further, the hole is closed by its elasticity of the projecting part and the liquid tightness is maintained even after the inversion. |
