Bend controllable tubular shaft for laparoscopic instrument, has outer tube formed as screw element that traverses bendable and rigid sections, where screw element is rigidly reinforced in rigid sections

摘要

The shaft has two bendable sections (3, 5) limited by side rigid sections (2, 6) and a middle rigid section (4) in a longitudinal direction, where the shaft is defined by one of the bendable sections in an outer tube (1). The outer tube is formed as a screw element that traverses the bendable and rigid sections, where the screw element is rigidly reinforced in the rigid sections. A stiffener is formed at longitudinal strips e.g. weld seams, distributed around a circumference. The screw element consists of a flat band. Windings of a metal wire are welded with one another at the strips.