BENDING STRUCTURE AND JOINT FUNCTION PART

WIPO Patent Application WO/2021/162089

A1

Provided are a bending structure and a joint function part with which it is possible to enhance structural simplicity while improving the stability of a bending movement. A bending structure in which an inner coil part 5 is positioned inside an outer coil part 3. The outer coil part 3 has a plurality of gaps 3c across which winding parts 3b that are adjacent in the axial direction are set apart from each other. In the inner coil part 5, winding parts 5a are provided in correspondence with the gaps 3c in the outer coil part 3, and are fitted between adjacent winding parts 3b of the outer coil part 3 while in contact with the winding parts 3b. A dimension P is set so as to be within a range satisfying πR/4N≤P