Endoscope Bending Section Segmented Comb Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing endoscope bending sections face challenges in manufacturing when trying to make them longer and thinner, as the narrow passages for pull-wires become prone to failure due to long and thin retractable cores used in the moulding process.
Innovation Solution
The endoscope features a bending section with two elongate parts forming comb-like structures, allowing for a single lumen during injection moulding, using a large single longitudinal core for increased mechanical strength and facilitating assembly by sideways joining of the parts, which simplifies the manufacturing process and reduces stress on the bridges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the bending section is made longer and thinner with increased segments, then the flexibility and manoeuvrability of the endoscope is improved, but the passages for pull-wires become very narrow and the retractable cores become very long and thin, making them more prone to failure
Solution Approach 1:
The bending section is divided into two separate elongate parts (first and second bending section parts), each with its own comb-like structure. This segmentation allows each part to be manufactured independently with robust cores, avoiding the reliability issues of single long thin cores while achieving the desired flexibility through the articulated arrangement of multiple segments across both parts.
Solution Approach 2:
The bridges of the first bending section part extend in a first direction while the bridges of the second bending section part extend in a second direction transverse to the first direction. This dimensional arrangement allows the pull-wire passages to be oriented in different directions, enabling the use of shorter, more robust retractable cores in each part while maintaining overall flexibility.
2Shape
If the bending section is made longer and thinner, then the outer diameter is reduced, but the passages for pull-wires become very narrow
Solution Approach 1:
Dividing the bending section into two separate parts allows the pull-wire passages to be distributed across both parts. Each part can have simpler, wider passages suitable for robust core manufacturing, while the combined structure achieves the required small outer diameter through efficient spatial arrangement.
Solution Approach 2:
By orienting the bridges and passages in different directions (first direction for first part, second transverse direction for second part), the design accommodates pull-wire passages in multiple dimensions. This allows for larger passage cross-sections in each part while maintaining the overall compact external dimensions of the bending section.
3Ease of manufacture
If the bridges are just attached as hinges to neighbouring segments, then the assembly is simple, but the bending stresses are concentrated over only the distance between two neighbouring segments
Solution Approach 1:
The bridges of the first bending section part and the bridges of the second bending section part are arranged to extend in different directions and work together to provide combined bending support. This merging of bridge functions in perpendicular directions distributes the bending stress across a larger volume of material, enhancing mechanical strength while maintaining the articulated hinge-like flexibility.
Solution Approach 2:
The bridges extend in two different directions (first direction and second transverse direction), creating a three-dimensional stress distribution network. This dimensional arrangement allows bending stresses to be distributed across both directional axes, significantly improving the mechanical strength and stress resistance of the bending section compared to single-direction hinge attachments.
Data Source
Figure 1
Figure 2~3
Figure 4a~4b
AI summary
An endoscope comprising a handle at the proximal end, an insertion tube connected to the handle. The insertion tube comprises a bending section (6). The bending section (6) comprises a first elongate bending section part (10) and a second elongate bending section part (10'). The first elongate bending section part (10) comprises a number of first annular members (13). The first annular members (13) are arranged in a row and interconnected by a number of first bridges (14) so as to form a first comb-like structure. The second elongate bending section part (10) comprises a number of second annular members (13'). The second annular members (13') are arranged in a row and interconnected by a number of second bridges so as to form a second comb-like structure. The outer circumferential surface of at least some of said first annular members (13) comprise a groove adapted to receive and accommodate a second bridge of said second bending section part (10') and the outer circumferential surface of at least some of said second annular members (13') comprise a groove adapted to receive and accommodate a first bridge (14) of said first bending section part (10).