Bicycle Axle Assembly Anti-Rotational Nut Mechanism

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing bicycle wheel quick release mechanisms often require assistance to remove and reinstall wheels, and they can lose axle retaining force during removal, making it difficult for a single person to manage.

Innovation Solution

A bicycle axle assembly featuring a nut member with a first and second part, including anti-rotational structures that move between engaged and disengaged positions, allowing for single-handed removal and reinstallation while maintaining the original axle retaining force, utilizing a locking projection to secure the wheel to the frame.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a typical quick release mechanism with a skewer and cam structure is used, then wheel removal and reinstallation is facilitated, but it requires assistance from another person to stabilize the bicycle during operation

Engineering Contradiction:
Improvewheel removal and reinstallationVSAvoidneed for additional person
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The nut member is designed to self-stabilize during wheel removal and reinstallation by engaging its projection with the dropout, eliminating the need for another person to hold the bicycle. The anti-rotational structures between the first and second parts provide self-limiting rotation that maintains stability throughout the operation.

Inventive Principle:
Principle #25Self-service

2Ease of operation

If a typical quick release mechanism is used, then wheel removal is enabled, but the axle retaining force is lost during removal

Engineering Contradiction:
Improvewheel removalVSAvoidaxle retaining force
Core Design Contradiction:
Ease of operationVSStrength

Solution Approach 1:

The nut member transitions dynamically between states: during removal, the anti-rotational structures disengage to allow rotation; during reinstallation, they re-engage to restore axial retention. The projection continuously engages the dropout to maintain lateral stability throughout the entire cycle, preserving axle retaining force when needed.

Inventive Principle:
Principle #15Dynamics

3Ease of operation

If a nut member with anti-rotational structures is used, then single-handed operation is enabled, but the structure becomes more complex

Engineering Contradiction:
Improvesingle-handed operationVSAvoidnut member structure
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The nut member is segmented into a first part and a second part with distinct functions: the first part provides threading and anti-rotational structures, while the second part provides the projection for dropout engagement. This segmentation allows each part to be optimized for its specific function while working together to achieve single-handed operation.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP2599704B1Bicycle axle assembly
Publication Date: 2016.07.27 SHIMANO SINGAPORE PRIVATE LTD
  • EP2599704B1 patent drawingFigure 1
  • EP2599704B1 patent drawingFigure 2~3
  • EP2599704B1 patent drawingFigure 4~5

AI summary

A bicycle axle assembly (14) has a nut member t(26, 126, 226) hat includes a first part (50, 150, 250) and a second part (52, 152, 252). The first part has an internal thread. The second part has a projection (54, 154, 254) that is arranged to engage a dropout (48) of a bicycle frame. The first and second parts have first and second anti-rotational structures (56156, 256; 58, 158, 258), respectively, that move relative to each other between an engaged position, in which the first and second parts are non-rotatably engaged relative to each other by the first and second anti-rotational structures, and a disengaged position, in which the first and second mating anti-rotational structures are disengaged such that the first and second parts rotate relative to each other.