Bicycle Rear Triangle Segmentation for Mud Clearance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing rear triangle designs for tubular bicycle frames with a classic diamond shape face issues such as mud and stone accumulation, structural weak points, and increased wheelbase, which hinder performance and agility, particularly in off-road cycling.
Innovation Solution
A rear triangle composed of two distinct half-triangles with articulated connections using Hirth-type joints and rocker arms, allowing for synchronous movement and reducing the risk of mud accumulation while maintaining a compact wheelbase.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the rear triangle is made in a single piece with bridges, then structural strength is improved, but mud and stone accumulation occurs in gaps creating harmful factors
Solution Approach 1:
The rear triangle is divided into two separate half-triangles that are joined at the pivot point, eliminating the need for bridges. This segmentation removes the gaps where mud and stones would accumulate while maintaining structural integrity through the articulation joint.
Solution Approach 2:
The bridges (lower and upper) are completely removed from the design. By extracting these bridge elements, the patent eliminates the problematic gaps they created, allowing the chain stays and seat stays to connect directly at the pivot point without creating mud-trapping regions.
2Object-affected harmful factors
If the rear triangle is made in two distinct pieces, then mud accumulation is reduced, but structural weak point is created at the joint
Solution Approach 1:
The two half-triangles are merged at the pivot point through rigid articulation joints. This combining of separate pieces at the critical connection point eliminates structural weak points while maintaining the benefits of segmentation elsewhere in the design.
Solution Approach 2:
Instead of joining pieces with flexible bindings or welds that create weak points, the patent uses rigid articulation joints that provide both connection strength and rotational freedom. The inversion approach uses rigid rather than flexible connections at the joint.
3Ease of operation
If chain stay length is increased to improve tire turning, then tire turning is improved, but wheelbase increases reducing agility
Solution Approach 1:
The rear triangle is designed with dynamic articulation joints that allow controlled movement and rotation. This dynamic design enables the tire to turn effectively through the articulated connections without requiring increased chain stay length, thereby maintaining a short wheelbase and high agility.
Data Source
AI summary
A rear triangle of a tubular bicycle frame, which comprises a tubular structure which defines at least one head tube for connection to a front fork, a first horizontal tubular body, which is connected to the head tube and defines an inlet for mounting a saddle post, and a second, oblique tubular body and a third, vertical tubular body.The rear triangle is composed of a first half-triangle and a second half-triangle, each one composed of a pair of horizontal chain stays which at one end are rigidly connected to a pair of distinct oblique seat stays so as to define, for each one of said pairs of horizontal chain stays and oblique seat stays, a V-shape.The upper and lower free ends of the pairs of horizontal chain stays and oblique seat stays are articulated to third tubular body so that they can oscillate.