Multi-articulated manipulator

A multi-articulated manipulator having a driving means which comprises more than one hollow outer shells arranged in series in a lengthwise direction, an articulation connecting adjoining joints of the outer shells in a bending manner, grasping members connected in a bending manner to a foremost one of the outer shells, a power transmission shaft fit to the outer shells to operate the grasping members for extending, contracting and bending manner, and a linkage mechanism connecting the power transmission shaft with the outer shell at the articulation to bend the outer shells, in synchronizing manner in the same direction the foremost outer shell and the intermediate outer shell,

• wherein the power transmission shaft is composed of a foremost outer shell constituting one of the outer shells and operating a pair of claw members for the grasping members independently from each other, a pair of claw power transmission shafts fit in an intermediate outer shell and a basement outer shell and mounted for rocking movement, and outer shell power transmission shafts fit in the basement outer shell and intermediate outer shell to be able to bend the foremost outer shell and the intermediate outer shell in the same direction and further fastened in a rocking manner to basement outer shell and the intermediate outer shell,
• wherein the linkage mechanism has a nut having female threads mating with male threads formed on the claw power transmission haft and the outer shell power transmission shaft, and a linkage member connecting the nut with the outer shell, and
• wherein upon rotation of the claw power transmission shaft, the nut moves axially along the male threads and the linkage mechanism moves in association with the movement of the nut so as to make opening/closing movement or bending movement in same direction of the claw members of the grasping members, and further upon rotation of the outer shell power transmission shaft, the nut moves axially along the male threads and at the same time the linkage mechanism is operated to bend the adjacent outer shells relatively to each other.