PROBLEM TO BE SOLVED: To provide a medical treatment tool for efficiently transmitting an operation input and generating large grasping force with the small operation input.SOLUTION: The medical treatment tool 1 includes: a treatment section 10 having a first forceps piece 11 and a second forceps piece 12, at least one of which is rotatably supported with respect to a cover member an operating member 20 that moves to advance and retract with respect to the cover member in its own axial direction, so that the pair of forceps pieces rotates and opens and closes and link members 15, 17 the distal ends 15A, 17A of which are linked to the rotatable forceps pieces, and the proximal ends 15B, 17B of which are linked to the operating member. The advancing and retracting axis of the proximal end is parallel to the axis of the operating member a distance between the advancing and retracting axis of the proximal end and the distal end is shorter than the length of the link member and the length of projection on the advancing and retracting axis of a line segment which connects the proximal end and the center of rotation of the first forceps piece and the second forceps piece is shorter than the length of projection on the advancing and retracting axis of a line segment which connects the distal end and the center of rotation.COPYRIGHT: (C)2013,JPO&INPIT【課題】操作入力が効率よく伝達され、小さい操作入力で大きい把持力を発生させることができる医療用処置具を提供する。【解決手段】本発明の医療用処置具1は、少なくとも一方がカバー部材に対して回動可能に支持された第一鉗子片11および第二鉗子片12を有する処置部10と、カバー部材に対して自身の軸線方向に進退することにより一対の鉗子片を回動させて開閉させる操作部材20と、回動可能な鉗子片に先端部15A、17Aが連結され、基端部15B、17Bが操作部材に連結されたリンク部材15、17とを備え、基端部の進退軸は、操作部材の軸線と平行であり、基端部の進退軸と先端部との距離は,リンク部材の長さより短く,基端部と第一鉗子片および第二鉗子片の回動中心とを結んだ線分を前記進退軸に射影した長さは、先端部と回動中心を結んだ線分を進退軸に射影した長さよりも短いことを特徴とする。【選択図】図3
