Catheter Distal Tip Bonded to Coil Inner Surface
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Therapeutic catheters inserted into hard stenoses or bones face issues with insertion performance due to a rigid metal distal end tip that increases the outer diameter, leading to bonding strength issues and risk of separation, potentially causing damage to vessels or ducts.
Innovation Solution
A catheter design where the metal distal end tip is bonded to the inner surface of a coil body at the distal end of the catheter shaft, maintaining sufficient bonding strength without increasing the outer diameter, reducing the risk of separation and improving insertion performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a rigid metal distal end tip is bonded to the outer peripheral surface of the braid, then sufficient bonding strength is achieved, but the outer diameter of the distal end tip becomes greater than the outer diameter of the catheter shaft, degrading insertion performance
Solution Approach 1:
The bonding interface is transitioned from an external surface (outer peripheral surface of braid) to an internal surface (inner surface of coil body). This dimensional shift allows the distal end tip to be bonded within the catheter shaft structure, maintaining the outer diameter while achieving sufficient bonding strength through the inner surface attachment.
Solution Approach 2:
The distal end tip is nested within the coil body structure, with the tip bonded to the inner surface of the coil body. This nesting arrangement allows the tip to be contained within the overall catheter shaft diameter, preventing diameter increase while securing the tip through internal bonding.
2Adaptability or versatility
If the catheter is greatly bent to reach hard stenosis at the end of blood vessel, then the catheter can access the target location, but load concentrates at the bonding portion between the distal end tip and the braid, risking separation
Solution Approach 1:
The bonding interface is relocated from the external braid surface to the internal coil body surface. This internal bonding position is more favorably positioned to resist bending-induced separation forces, as the inner surface bonding creates a more robust connection that better withstands the concentrated loads generated during catheter bending and rotation.
3Ease of operation
If the distal end tip is rotated while greatly bent and caught on hard stenosis, then the catheter can be maneuvered, but the proximal end of the distal end tip may separate from the braid due to concentrated load
Solution Approach 1:
The bonding interface is shifted to the inner surface of the coil body, where the bonding geometry and structural support better resist rotational and bending loads. The internal bonding position provides enhanced mechanical interlocking and load distribution, preventing separation during rotation and maneuvering operations.
4Ease of operation
If the proximal end of the distal end tip separates from the braid, then the catheter can be manipulated, but the separated tip may break through the outer layer and damage normal portions of the blood vessel
Solution Approach 1:
The bonding interface relocation to the inner surface of the coil body creates a more secure connection that prevents tip separation. This internal bonding ensures the distal end tip remains firmly attached during manipulation, eliminating the risk of tip breakage and subsequent damage to blood vessel walls.
Solution Approach 2:
The design proactively prevents tip separation through robust inner surface bonding, thereby preventing the harmful consequence of tip breakage and vessel damage before it can occur. The strengthened bonding interface acts as a preventive measure against potential catastrophic failure.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A catheter (1,1a,1b) includes a catheter shaft (10) extending from a proximal end to a distal end and comprising a main body (13) and a distal end portion (33), and a distal end tip (50). The main body (13) includes an inner layer (20) defining a first space (22), a coil body (30) wound around an outer periphery of the inner layer and made of a metal, and an outer layer (40) that covers an outer periphery of the coil body (30). The distal end tip (50) defines a second space (52) that communicates with the first space. The distal end tip (50) is provided at a distal end of the catheter shaft (10), and is made of a metal. The distal end portin (33) includes the coil body (30) and the outer layer (40). The distal end tip (50) is bonded to a distal end (32, 32a) of the coil body (30) and an inner surface (34, 34a) of a distal end portion (33) of the coil body (30).