The bushing needle assembly body to have, be able to slide extension person in charge stopping position and the sharp point which stretching are done in inside the braking component which is arranged relatively the bushing needle housing which possesses the sluggish distal (2036) edge and proximal edge (18) with, the blade assembly body which possesses the sharp point (16,20,22) with, the bushing needle housing (18) vis-a-vis (24) with the distal (2036) edge where the sharp point is sluggish compared to distal (2036) to proximal edge direction than protection position pulling with the safe position which is packed the bushing needle housing (18) the blade assembly body (16,20,22), protection positionWhen cutting off organization the blade assembly body (16,20,22) with, when the braking component (24), it contacts organization, sliding to proximal position due to the contact with the organization, it exposes the sharp point and the person in charge stopping cancellation component (26) operates, the braking component (24), distal (2036) the braking component (24) it has the component which possesses the spring component which energization is done, contact with the organization is cancelled, to move distal (2036) due to the spring component, the braking component (24) with the movement to distal (2036) edge direction, the person in charge stopping cancellation component(26) operates, the blade assembly body (16,20,22) cancels from protection position and the blade assembly body (16,20,22) moves to safe position.< Selective figure >Figure 1套管針組立体は、鈍い遠位端及び近位端を有する套管針ハウジング(18)と、鋭利な先端部を有する刃組立体(16,20,22)と、套管針ハウジング(18)に対して相対的に配置される制動部材(24)とを備え、鋭利な先端部が鈍い遠位端よりも遠位に延伸する伸張係止位置と、鋭利な先端部が防護位置よりも近位端方向に引込む安全位置との間で套管針ハウジング(18)内で刃組立体(16,20,22)を摺動でき、防護位置の刃組立体(16,20,22)により組織を切断するときに、制動部材(24)は、組織に接触し、組織との接触により近位位置に摺動して、鋭利な先端部を露出しかつ係止解除部材(26)を作動し、制動部材(24)は、遠位に制動部材(24)を付勢するばね部材を有する部材を備え、組織との接触が解除されると、ばね部材により遠位に移動し、制動部材(24)の遠位端方向への移動により、係止解除部材(26)が作動し、防護位置から刃組立体(16,20,22)を解除して安全位置に刃組立体(16,20,2
