Non-overlapping Frame Folding Bike Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing folding bicycles are structurally weak and complicated to fold, as they often require multiple steps and have overlapping frame members during folding, which can lead to instability and increased manufacturing tolerances.
Innovation Solution
A novel fastening system positioned near the seat tube allows the front and rear frames to bypass each other during folding, using an innovative mechanism with wedges at varying angles for primary and secondary retention, which automatically engages during unfolding and preloads the hinging mechanism to provide a rigid riding position, reducing hinge/axis of rotation tolerances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a hinging member is inserted into a cut main tube near the middle of the bicycle to fold the bicycle, then the bicycle can be folded, but the structural strength is reduced and the folding process becomes complicated requiring multiple steps
Solution Approach 1:
The bicycle frame is divided into separate front and rear frame members that can be independently positioned and folded relative to each other, rather than using a single continuous main tube that must be cut and hinged. This segmentation allows folding without compromising the integrity of the main structural tubes.
Solution Approach 2:
The front frame member is positioned within or alongside the rear frame member during folding, with the front frame bypassing the rear frame in a non-overlapping manner. This nesting arrangement allows compact folding while maintaining structural strength through proper load distribution.
2Ease of operation
If frame members overlap during folding, then the folding process is simplified, but manufacturing tolerances increase and structural weakness occurs
Solution Approach 1:
A fastening assembly acts as an intermediary mechanism between the front and rear frame members, providing precise alignment and positioning during folding. This fastening system ensures that the frames meet at specific predetermined positions without overlapping, thereby maintaining manufacturing precision while enabling smooth folding operation.
3Ease of operation
If the fastening mechanism is positioned above the uppermost surface of the front frame, then the locking mechanism is easily accessible, but the bicycle becomes heavier and more complex to manufacture
Solution Approach 1:
The fastening assembly is merged with the existing frame structure, with components integrated into the front and rear frame members rather than being separate protruding elements. This integration reduces overall weight while maintaining accessibility through strategic positioning and design of the fastening components.
4Device complexity
If the fastening mechanism handles all forces during riding, then the bicycle can be simpler in structure, but the actuating mechanism becomes overly complex and less reliable
Solution Approach 1:
The load-bearing function is extracted from the actuating mechanism and transferred to dedicated fixed meeting surfaces and structural frame components. The fastening mechanism's actuating parts are relieved of force handling duties, focusing only on locking and retention functions, which simplifies the actuation system and improves reliability by separating structural support from actuation functions.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enhances the structural strength and simplifies the folding process by ensuring non-overlapping frames during folding, providing a lightweight, easy-to-manufacture, and cost-effective bicycle with improved rigidity and reduced manufacturing tolerances, allowing forces during riding to be handled by fixed meeting surfaces rather than the actuating mechanism.
Implementation Method 1
an assembly of wedges that are at varying angles relative to one another and working together to allow for a system where the secondary retention may automatically engage
Implementation Method 2
the act of locking the primary retention may also preload the hinging mechanism
Data Source
AI summary
A folding bike designed such that when the bicycle is folded, the front and rear frame structural members bypass each other in a non-overlapping manner except at folding and fastening positions using an axis of rotation at or near the seat tube, wherein the folding bicycle maintains a rigid riding position using an innovative fastening mechanism positioned to fasten by actuation of a member located not above the uppermost surface of the front frame, and which may be equipped with primary and secondary retention wherein the secondary retention may automatically engage when the bike is unfolded to the operative riding position.