Multi-Tendon Cable Deflection Deviator for Stress Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing traction systems with multi-tendon cables face challenges in managing angular deflection, leading to transverse contact stresses and uneven force distribution, especially under high traction forces, which can damage tendons and reduce cable capacity and durability.
Innovation Solution
A traction system with a deviator that guides tendons through a pattern of segments with channels, allowing for significant angular deflection (up to 180°) while maintaining tendon alignment and distributing forces uniformly, using a support structure with convex surfaces and abutments to control movement and prevent damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a deflection angle is introduced to the multi-tendon cable for pulling over obstacles or providing leverage, then the cable can navigate obstacles and provide sufficient leverage, but some tendons undergo larger tensile forces and transverse contact stresses which may damage the tendons and reduce cable capacity
Solution Approach 1:
The deviator is divided into multiple segments (first deviator segment, second deviator segment, etc.), each handling a portion of the deflection angle. This segmentation distributes the mechanical stress across multiple contact points rather than concentrating it at a single point, reducing the transverse contact stresses on individual tendons while maintaining the overall deflection capability.
Solution Approach 2:
The deviator segments are designed to be movable along the tendons, allowing the system to dynamically adapt to varying deflection requirements. The segments can shift positions based on the applied load and deflection angle, optimizing the force distribution and reducing peak stresses on the tendons during operation.
2Loss of energy
If pulleys are used to reduce friction efforts in deflection systems, then friction is reduced, but the solution becomes incompatible with multi-layer tendon arrangements and very high traction forces due to excessive friction and stress at axles and bearings
Solution Approach 1:
The invention extracts the friction-generating elements (axles and bearings) from the system by replacing pulleys with a deviator system that guides tendons through channels. This eliminates the rotational friction at axles and bearings, allowing the system to handle very high traction forces without excessive friction losses while maintaining compatibility with multi-layer tendon arrangements.
Solution Approach 2:
The deviator segments act as intermediaries between the tendons and the support structure. Instead of tendons directly contacting pulley surfaces with high friction, they are guided through channels in the deviator segments, which distribute the contact stresses and reduce frictional losses while maintaining effective force transfer.
3Adaptability or versatility
If tendons are pressed against each other on the inner side of curvature during deflection, then the cable can achieve deflection, but transverse contact stresses increase which may damage the tendons and hinder transfer of traction forces to the load
Solution Approach 1:
The deviator is segmented into multiple sections, each providing a portion of the total deflection angle. This segmentation reduces the curvature radius requirement and distributes the transverse contact stresses across multiple segments rather than concentrating them at a single high-curvature point, improving both deflection capability and force transfer efficiency.
Solution Approach 2:
The deviator segments serve as intermediaries that guide and separate the tendons during deflection. The channels in the deviator segments maintain proper tendon spacing and alignment, preventing excessive transverse contact between tendons on the inner side of the curvature while still achieving the required deflection angle.
Data Source
Figure 1A~2
Figure 3A~3C
Figure 4A~4C
AI summary
The traction system comprises a plurality of substantially parallel tendons (2) movable for pulling a load, the tendons being disposed according to a pattern in a plane perpendicular to the tendons; and at least one deviator (3) for guiding the tendons, the deviator accommodating an angular deflection of the plurality of tendons. The deviator includes a support structure (4) and a plurality of segments (5) each having an inner surface facing a convex surface of the support structure, front and rear surfaces and a plurality of channels extending from the front surface to the rear surface. The channels are disposed according to said pattern in the front and rear surfaces of each segment, each tendon being received in a respective one of the channels. At least some of the segments (5) have their inner surfaces bearing on the convex surface of the support structure (4) in response to tensile forces applied to the tendons.