Pivoting Guide Rollers for Constant Rope Wrap Angle
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Solution Overview
Problem
Endless rope exercise devices suffer from a lack of flexibility in pull angle and slippage of the rope off rollers/pulleys due to inadequate rope alignment and tension management.
Innovation Solution
The design incorporates a dynamic head assembly with a drive roller and independently pivoting guide rollers that maintain a constant wrap angle of the rope, ensuring proper alignment and tension regardless of the pull angle, along with a resistance assembly for adjustable resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If fixed rollers are used to guide the rope, then the structure is simple, but the rope slips off the rollers when pulled at various angles
Solution Approach 1:
The guide rollers are made dynamically adjustable rather than fixed. Each guide roller can independently pivot about its roller axis and the pair pivots together as a unit about the drive shaft axis, allowing the system to adapt to varying rope pull angles while maintaining reliable rope grip without requiring complex mechanical structures
2Adaptability or versatility
If the rope is allowed to pull at various angles, then the exercise flexibility is improved, but the wrap angle of contact varies causing slippage
Solution Approach 1:
The guide rollers dynamically adjust their orientation to maintain optimal rope contact. The ability of the guide rollers to pivot independently and as a unit allows the system to accommodate various pull angles while maintaining a substantially constant wrap angle of contact, ensuring reliable rope grip across different exercise positions
Solution Approach 2:
The guide rollers automatically self-adjust to the correct orientation based on the rope pull angle without requiring external control mechanisms. The rollers pivot themselves into the proper position to maintain constant wrap angle, providing self-regulating adaptability that ensures both flexibility and reliability
3Reliability
If the guide rollers are fixed relative to the drive roller, then the structure is simpler, but the wrap angle cannot be maintained constant when pull angle changes
Solution Approach 1:
The guide rollers are mounted on pivoting mechanisms that allow them to move dynamically while maintaining functional simplicity. The dual-pivot capability (independent roller pivot and unit pivot about drive shaft) enables constant wrap angle maintenance through natural mechanical adaptation rather than complex active control systems
Data Source
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AI summary
An endless rope trainer that includes an upright frame, a drive roller supported a distance above ground on the frame, an endless rope entrained around the drive roller, and a means of applying resistance to rotation of the drive roller. A pair of guide rollers are provided proximate the drive roller. The guide rollers pivot together as a unit about the axis of the drive roller independently of the drive roller for maintaining a constant wrap angle of contact of the endless rope on the drive roller regardless of pull angle on the endless rope.