| 摘要 |
PROBLEM TO BE SOLVED: To provide an endoscope in which the screw-in force (torque) applied repeatedly each time a treatment instrument (treatment instrument attachment) is mounted to a mouthpiece member is distributed to thereby prevent the destruction of a collar member supporting the mouthpiece member and also the trouble that the mouthpiece member rotates relative to the collar member.SOLUTION: A non-circular raised fitting part includes: a circular raised cylindrical surface formed of a portion of a cylindrical surface with the axis of a metallic mouthpiece member as its center; and a plurality of raised detents projecting outward in a radial direction of an extension surface of the circular raised cylindrical surface in a region where the circular raised cylindrical surface is not present. A non-circular recessed fitting hole includes: a circular recessed cylindrical surface which is engaged with the circular raised cylindrical surface; and a plurality of recessed detents which project outward in the radial direction of an extension surface of the circular recessed cylindrical surface and which are engaged with the raised detents. |
