Patent ID: 9345390
Filing Date: 2016-05-24
CPC Classification: A61B,G02B

Claim Text:
1. An endoscope including an insertion portion which exhibits flexibility to be inserted into a body cavity, the endoscope comprising: a bending portion formed at a distal end side which is configured to be maximally bent with a first curvature radius and to be bendable according to a bending operation by an operator, the bending portion being provided inside thereof a plurality of annular bending pieces which are rotatably connected in series by pivots, peripheral edges of opposite surfaces of adjacent ones of the bending pieces serving as abutment portions to abut to each other to regulate the curvature radius at which the bending portion is maximally bent; a first flexible tube portion connected in series at a proximal end side of the bending portion, which is maximally bendable with a second curvature radius larger than the first curvature radius, and which is bent when applied with an external force but is not bendable according to a bending operation by an operator, the first flexible tube portion being maximally bent by being pushed against an inner wall of the body cavity, the first flexible tube portion being provided inside thereof a plurality of curvature regulation pieces rotatably connected in series by pivots, peripheral edges of opposite surfaces of adjacent ones of the curvature regulation pieces serving as abutment portions to abut to each other to regulate the curvature radius at which the first flexible tube is maximally bent; and a second flexible tube portion connected in series at a proximal end side of the first flexible tube portion, the second flexible tube portion comprising a helical tube, a braid covering an outer circumference of the helical tube, and an outer resin coat covering the braid, the second flexible tube portion having a flexural rigidity larger than a flexural rigidity of the first flexible tube portion.