Patent ID: 8652030

Claim:
A two-part bending endoscope comprising: an insertion portion; a bending portion arranged on the insertion portion, the bending portion including a first bending part and a second bending part, wherein the first bending part is arranged on one side of the bending portion, and the seconds bending part is arranged on an other end side of the bending portion and linked with the first bending part; an operation portion; and a bending portion operation apparatus which is provided on the operation portion so as to be linked with a proximal end of the insertion portion, the bending portion operation apparatus including a first operation device for causing the first bending part to perform a bending action and a second operation device for causing the second bending part to perform a bending action, wherein: the bending portion operation apparatus includes a selective power-transmitting mechanism section which enables at least a bending action of the first bending part by the first operation device, and an interlocking operation of the second bending part and the first bending part by the second operation device; the selective power-transmitting mechanism section is an independent rotation/co-rotation mechanism section; and the independent rotation/co-rotation mechanism section includes: a shaft arranged on the first operation device; a first rotation body whose cross-sectional shape is a regular polygon, the first rotation body being integrally fixed to the shaft; a ring-shaped member arranged on the second operation device; a second rotation body which is integrally fixed to the ring-shaped member, the second rotation body including a first rotation body arranging recessed portion in which the first rotation body is rotatably arranged and whose cross-sectional shape is a regular polygon, and a hole through which the shaft passes; a plurality of stepped pillar members, each including: a globe portion which has a predetermined diameter and which is arranged in a gap formed by an inner surface of the first rotation body arranging recessed portion and an outer surface of the first rotation body; a small-diameter portion to which the globe portion is integrally fixed; and a large-diameter portion as a sliding portion; and a rotational force transmission switching section including a through hole through which the shaft passes, long holes in which the respective small-diameter portions of the stepped pillar members are slidable, the long holes being formed in an elongated shape in a central axis direction of the through hole, and a case body having a space portion in which the respective large-diameter portions of the stepped pillar members are slidably arranged.