Elongated Spoke Holes and Angular Alignment for Bicycle Wheel Stability
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Solution Overview
Problem
Existing bicycle wheel spoke fastening systems face challenges with using tubeless tires due to complex rim designs and high spoke tension, leading to increased spoke breakage and assembly complexity.
Innovation Solution
A wheel with elongated spoke holes and a holding element that allows angular alignment of the spoke nipple, distributing forces over a larger area, reducing rim thickness and minimizing lateral stresses, enabling easy assembly and reduced spoke breakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If spoke holes are made small to secure spoke nipples, then spoke retention is improved, but tubeless tire installation becomes difficult
Solution Approach 1:
The spoke hole is segmented into two functional zones: a large outer opening area that allows easy insertion of spoke nipples and accommodation of tubeless tires, and a smaller inner retention area that securely holds the spoke nipple. This segmentation resolves the contradiction by providing both large access and small secure retention.
Solution Approach 2:
Different regions of the spoke hole have different dimensions and functions. The outer region has a larger diameter for easy insertion and tubeless tire compatibility, while the inner region has a smaller diameter for secure spoke nipple retention. This local differentiation of hole quality resolves the contradiction between ease of installation and secure retention.
2Stability of the object's composition
If rim wall thickness is increased to provide stability, then wheel stability is improved, but wheel weight increases
Solution Approach 1:
The load-bearing function is segmented from the rim wall to the holding elements. The rim wall can be made thinner since it no longer needs to bear the full spoke load, while the holding elements (arranged in elongated slots) provide the necessary stability and force distribution. This segmentation allows weight reduction while maintaining stability.
Solution Approach 2:
Instead of increasing rim wall thickness in the radial dimension to achieve stability, the solution transitions to a different dimension by using elongated holding elements arranged in circumferential slots. This dimensional shift allows stability to be achieved through distributed force bearing in the circumferential direction rather than through radial wall thickness.
3Strength
If spoke nipples are tightly fitted in spoke holes, then spoke tension is improved, but lateral forces and buckling stresses increase
Solution Approach 1:
The spoke hole is segmented into a large outer opening for insertion and a smaller inner retention zone. This segmentation allows the spoke nipple to be inserted easily while maintaining secure retention, reducing lateral forces during installation while preserving necessary spoke tension.
Solution Approach 2:
The dimensions of the spoke hole are optimized to specific parameter ranges that balance retention and stress reduction. The hole diameter is precisely controlled to be small enough for secure retention but large enough to minimize lateral forces and buckling stresses, representing a parameter optimization approach.
Data Source
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AI summary
The wheel has a hub with spokes arranged between a hub housing and a rim, which has a rim base that includes spokes holes. A fastening unit (33) of a spoke fastening system (100) is arranged in each hole that extends in a peripheral direction of the wheel longer than in axial direction. A spoke nipple (31) and the unit are designed, such that an angle-moderate variable adjustment of the spoke to the rim is allowed. A nipple head (43) is designed rounded and received in a rounded designed nipple head retainer (44) of the unit that is made of light metal and fiber-reinforced plastic.