Product Overview

The unidirectional bending section tube is the core tube component for controllable steering at the distal tip of an endoscope. The figure shows an integrated pre-installed pull-wire assembly, composed of a proximal straight hypotube + distal unidirectional bending section, polymer sheath, distal tip base, and externally routed pull wire. Pulling the exposed pull wire drives the distal tip of the bending section to bend in a single direction; releasing the pull wire allows spring-back and reset via the sheath and joint structure. The finished product is fully assembled, requires no separate wire threading by the customer, and can be directly connected to an endoscope handle. It is commonly used as the steering unit of single-use minimally invasive endoscopes.

Structure and Materials

• Bending section body: medical-grade 316L stainless steel, laser-cut and formed, bending segments spin-riveted and hinged, with built-in travel limits to prevent failure from over-bending, meeting medical biocompatibility requirements

• Pull wire: medical-grade stainless steel ultra-fine wire, low friction, high tensile strength, led out from the proximal end of the tube (dual-wire layout shown in the figure)

• Outer sheath: medical polymer tubing, fully covering the articulation skeleton area, smooth and wear-resistant, isolating body fluids, improving passage through body cavities

• Distal and proximal bases: metal connector bases, precision positioned, facilitating assembly with the endoscope distal camera module and proximal sheath tube

Product Features

1. Unidirectional targeted bending: active steering in only one direction, with strong rigidity in the reverse direction, stable support and resistance to buckling, clear operational feedback, suitable for simplifying handle drive mechanisms.

2. Delivered as a pre-installed pull-wire assembly: the bending section, sheath, and pull wire are pre-assembled, eliminating customer steps for wire threading and adjustment, greatly reducing overall assembly difficulty and labor hours.

3. Customizable dimensions and bend angles: outer diameter, inner diameter, effective bending length, number of bending segments, maximum bending angle, and bending radius can be customized on demand; ultra-small outer diameter specifications are supported to fit narrow cavities.

4. Reserved internal lumen: the central through-hole of the tube can accommodate image cables, illumination fibers, and instrument channels, offering high integration.

Applications

Single-use nasopharyngoscopes, simple gastrointestinal endoscopes, urological endoscopes, and minimally invasive examination instruments; also suitable for small-diameter industrial borescope inspection equipment; ideal for projects requiring overall device cost control and simplified handle structures.