| 摘要 |
The purpose of the present invention is to provide an injection needle assembly which can decrease the force needed to attach the injection needle assembly and a drug discharge pipe and which, even when a weak force is used, can reliably achieve said attachment without leaking. This injection needle assembly (2) is provided with: an injection needle (11); a fitting unit (12) which is formed in a cylinder shape, one end thereof being a fitting opening, and which is formed into a female-type tapered shape, the inner diameter of the cylindrical hole thereof becoming smaller from the fitting opening towards the back; and a hub (13) in which the fitting part (12) is disposed and which holds the injection needle (11). This injection needle assembly (2) is used by the female-type tapered shape of the fitting unit (12) being fitted via the fitting opening onto the drug discharge pipe (22), which is formed in a male-type tapered shape, the outer diameter of the cylinder becoming smaller towards the leading end, and when the taper ratio of the male-type tapered shape of the drug discharge pipe (22) is N/100, then the female-type tapered shape of the fitting unit (12) is formed with an M/100 taper ratio, where M>N. |
