PROBLEM TO BE SOLVED: To provide a body cavity insertion instrument for normally fixedly adjusting the tension of wires for bending a bending part without performing complicated work.SOLUTION: An endoscope 1 includes: an insertion part 2 having the bending part 6 for performing a bending operation, and to be inserted into a body cavity an operation part 3 arranged closer to the proximal end compared with the insertion part 2 and the wires 28A, 28B whose distal ends are connected to the bending part 6 so as to bend the bending part 6 by being pulled or loosened. The endoscope 1 also includes: a pulley 27 to which the proximal ends of the wires 28A, 28B are connected and which pulls or loosens the wires 28A, 28B by rotating with a rotational axis as a center a mobile unit 15 arranged in the operation part 3 so as to be movable by self weight and an electromagnetic clutch 13 to change an actuation state between the first actuation state for regulating the movement of the mobile unit 15 and the second actuation state for not regulating the movement of the mobile unit 15.COPYRIGHT: (C)2012,JPO&INPIT【課題】複雑な作業を行うことなく、湾曲部を湾曲させるワイヤの張力を常に一定に調整することが可能な体腔内挿入器具を提供することにある。【解決手段】内視鏡1は、湾曲動作を行う湾曲部6を備え、体腔内に挿入される挿入部2と、挿入部2より基端方向側に設けられる操作部3と、先端が湾曲部6に接続され、牽引又は弛緩されることにより湾曲部6を湾曲させるワイヤ28A,28Bとを備える。また、内視鏡1は、ワイヤ28A,28Bの基端が接続され、回転軸を中心に回転することによりワイヤ28A,28Bを牽引又は弛緩するプーリ27を備え、操作部3に自重により移動可能な状態で設けられる移動ユニット15と、移動ユニット15の移動を規制する第1の作動状態と移動ユニット15の移動を規制しない第2の作動状態との間で作動状態が変化する電磁クラッチ13とを備える。【選択図】図3
