PROBLEM TO BE SOLVED: To provide an indwelling needle assembly where a seal function of a seal member is prevented reliably from being degraded in the respective states of putting an inner needle through a slit and pulling out the inner needle from the slit.SOLUTION: The indwelling needle assembly 1 is provided with: the inner needle 4 having an acute tip 41 at the distal end an inner needle hub 5 fixed to the proximal end of the inner needle 4 a hollow outer needle 2 which the inner needle 4 is put through an outer needle hub 3 fixed to the proximal end of the outer needle 2 and the sealing member 8 provided at the outer needle hub 3 and having the slit 81 which the inner needle 4 can be put through. The indwelling needle assembly 1 is provided with a correction member 30 for compressing the outer peripheral part of the sealing member 8. In an assembled state, the correction member 30 makes the outer peripheral surface of the inner needle 4 and the inner surface of the slit 81 adhere to each other and makes the inner surfaces of the slit 81 adhere to each other to keep a sealing function substantially. While the inner needle 4 is pulled out from the slit 81, the correction member 30 makes the inner surfaces of the slit 81 adhere to each other to keep the sealing function.COPYRIGHT: (C)2007,JPO&INPIT【課題】内針をスリットに挿通した状態および当該スリットから内針を抜去した状態の各状態で、シール部材のシール機能が低下するのを確実に防止することができる留置針組立体を提供すること。【解決手段】留置針組立体1は、先端に鋭利な針先41を有する内針4と、内針4の基端部に固定された内針ハブ5と、内針4が挿通される中空の外針2と、外針2の基端部に固定された外針ハブ3と、外針ハブ3に設けられ、内針4を挿通可能なスリット81を有するシール部材8とを有している。この留置針組立体1には、シール部材8の外周部を圧縮する矯正部材30が設けられ、矯正部材30により、組立状態では、内針4の外周面とスリット81の内面とが密着するとともに、スリット81の内面同士が密着して、実質的にシール機能が維持され、スリット81から内針4を抜去した状態では、スリット81の内面同士が密着して、シール機能が維持される。【選択図】図2
