PROBLEM TO BE SOLVED: To impose a restriction to a bending angle so that it does not become excessive by a curve direction instructed by operation.SOLUTION: An operation unit can be operated by a user, detects its operation, and outputs an operation detection signal. A curve instruction part generates a curve instruction signal on the basis of the operation detection signal. A first curve driving part curves an end of an insertion part in a first direction on the basis of the curve instruction signal, and a second curve driving part curves an end of the insertion part in a second direction orthogonal to the first direction. The curve instruction part adjusts a curve instruction amount so that a curve instruction amount in the first direction in the curve instruction into a cross direction is smaller than a curve instruction amount in the first direction in the curve instruction into the first direction and a curve instruction amount in the second direction in the curve instruction into the cross direction is smaller than a curve instruction amount in the second direction in the curve instruction into the second direction.SELECTED DRAWING: Figure 2COPYRIGHT: (C)2017,JPO&INPIT【課題】操作によって指示される湾曲方向により湾曲角度が過大になることを制限する。【解決手段】操作部はユーザーによる操作が可能であって、その操作を検出し、操作検知信号を出力し、湾曲指示部は操作検知信号に基づいて、湾曲指示信号を生成し、第1湾曲駆動部は湾曲指示信号に基づいて、挿入部の先端を第1方向に湾曲させ、第2湾曲駆動部は挿入部の先端を第1方向に直交する第2方向に湾曲させる。湾曲指示部は、操作検知信号に基づいて生成される湾曲指示信号が、第1方向と第2方向の両方に交差する交差方向への湾曲指示を示す場合、交差方向の湾曲指示における第1方向の湾曲指示量が、第1方向への湾曲指示における第1方向の湾曲指示量よりも小さく、且つ、交差方向の湾曲指示における第2方向の湾曲指示量が、第2方向への湾曲指示における第2方向の湾曲指示量よりも小さくなるように、湾曲指示量を調整する。【選択図】図2
