Patent ID: 9743827
Date: 2017-08-29
CPC Classifications: A61B,G02B

Claim:
1. An endoscope comprising: an insertion portion provided with a bending portion at a distal end part; an operation portion coupled to the insertion portion; four operation wires insertedly arranged inside the insertion portion and the operation portion, the four operation wires causing the bending portion to bend by being pulled/slackened; one operation member provided on the operation portion, the operation member having a rotation portion and being capable of performing a bending operation of the bending portion in four directions by being inclined with the rotation portion as a center; a rotation member provided in the operation portion and having a proximal end side and a distal end side, the proximal end side being connected to an opposite side of the operation member with the rotation portion as a center, and the rotation member pulling/slackening the four operation wires by being inclined with the rotation portion as a center in conjunction with an inclination operation of the operation member; and an amount-of-operation-force reducing portion, an end portion of which is movably held on the distal end side of the rotation member, the amount-of-operation-force reducing portion applying rotation torque to the rotation member in a direction in which the rotation member is inclined, in response to inclination of the operation member, to reduce an amount of operation force of the operation member, wherein the rotation torque of the amount-of-operation-force reducing portion increases with an increasing displacement of the operation member to offset and reduce the amount of operation force required for the inclination operation of the operation member.