Bicycle Fork Arch Torsional Stiffness Design

Solution Overview

Problem

Vehicle components, such as bicycle forks, face challenges in balancing strength and weight to optimize torsional stiffness and transverse shear stiffness, particularly in extreme performance scenarios where small weight and strength advantages are sought to enhance speed and jumping capabilities.

Innovation Solution

The implementation of a fork arch design that incorporates specific geometric features to optimize torsional stiffness and transverse shear stiffness, combined with material removal regions to reduce weight, particularly in low-stress areas, allowing for adjustable alignment and improved structural integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the fork arch is reinforced to improve torsional stiffness and transverse shear stiffness, then the structural strength is improved, but the weight of the fork arch increases

Engineering Contradiction:

Improvetorsional stiffness and transverse shear stiffnessVSAvoidweight of fork arch

Core Design Contradiction:

StrengthVSWeight of moving object

Solution Approach 1:

The patent applies local quality by implementing specific geometric features (such as arch curvature, thickness variations, and cross-sectional shapes) in different regions of the fork arch. These localized geometric modifications optimize stiffness in critical areas while maintaining lighter weight in non-critical areas, resolving the contradiction between overall strength and weight.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent utilizes curved geometric features in the fork arch design, such as arch-shaped structures and rounded transitions, which inherently provide better structural efficiency for resisting torsional and transverse loads compared to straight lines. This curvature principle allows achieving higher stiffness with less material, thereby reducing weight while maintaining strength.

Inventive Principle:

Principle #14Spheroidality (Curvature)

2Weight of moving object

If material is removed from the fork arch to reduce weight, then the weight is reduced, but the structural integrity and strength may be compromised

Engineering Contradiction:

Improveweight of fork archVSAvoidstructural integrity

Core Design Contradiction:

Weight of moving objectVSStrength

Solution Approach 1:

The patent applies local quality by implementing specific geometric features (such as arch curvature, thickness variations, and cross-sectional shapes) in different regions of the fork arch. These localized geometric modifications optimize stiffness in critical areas while maintaining lighter weight in non-critical areas, resolving the contradiction between overall strength and weight.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent incorporates alignment adjustment capabilities that allow preliminary positioning and optimization of the fork arch geometry before final assembly. This enables the structure to be pre-configured for optimal stress distribution, ensuring structural integrity is maintained even with reduced material.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS20240227978A9Fork arch

Publication Date: 2024.07.11 FOX FACTORY INC

AI summary

A fork arch is disclosed. The fork arch includes a torsional geometry portion to provide torsional stiffness. The fork arch also includes a transverse geometry portion to provide transverse shear stiffness, the transverse geometry portion intermingled with the torsional geometry portion to provide an optimized hybrid torsion and transverse shear stiffness for the fork arch.