Bicycle Rear Hub Connection Crown for Tool-Free Freehub Replacement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing connecting mechanism between the hub body and the freehub in bicycle rear hubs is difficult to disassemble and replace without specialized tools, leading to increased maintenance costs and reduced hub lifespan.
Innovation Solution
A connecting mechanism featuring a crenellated and splined connecting crown with an elastic ring, allowing for easy manual removal and replacement of parts without the need for special tools.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If an externally threaded connecting part is used to join the hub body and freehub, then the connection becomes very tight and secure during pedalling, but it becomes difficult to loosen and replace without special tools
Solution Approach 1:
The connecting mechanism is divided into two separate components: a connecting crown with external creneleation and a hub body with internal creneleation. This segmentation allows each part to be independently manufactured and replaced, solving the problem of difficult replacement while maintaining strong connection during use.
Solution Approach 2:
Instead of using traditional external threading that tightens irreversibly, the patent inverts the approach by using external creneleation on the connecting crown that engages with internal creneleation in the hub body. This inverted geometry allows for easy insertion and removal while maintaining secure connection during operation.
2Reliability
If a threaded connecting part is used, then the connection is secure and prevents loosening during pedalling, but special tools and knowledge are required for maintenance
Solution Approach 1:
The connecting crown is designed to be self-installing and self-securing through its external creneleation that engages with the internal creneleation of the hub body. The elastic ring provides automatic retention without requiring threaded fastening, allowing users to perform maintenance without specialized tools or knowledge.
Solution Approach 2:
The elastic ring acts as an intermediary element between the connecting crown and the hub body. It provides the retaining force necessary for reliable connection while allowing simple insertion and removal, eliminating the need for threaded fasteners and special maintenance tools.
3Stability of the object's composition
If traditional threaded connection is used, then the parts remain fixed during pedalling, but replacement increases maintenance costs and reduces hub lifespan
Solution Approach 1:
The connecting mechanism is segmented into replaceable components (connecting crown, elastic ring) that can be independently manufactured and replaced. This reduces maintenance costs compared to replacing the entire hub assembly, while the creneleated engagement ensures stable connection during pedalling.
Solution Approach 2:
The patent changes the connection parameter from irreversible threaded fastening to reversible creneleated engagement with elastic retention. This parameter change allows for easy replacement of wear components, reducing maintenance costs and extending hub lifespan while maintaining operational stability.
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
Facilitates easier maintenance by allowing for the easy removal and replacement of parts, reducing maintenance costs and prolonging the life of the hub and bicycle wheel.
Implementation Method 1
a connecting crown (7) and an elastic ring (8), which are the key innovative parts of the invention... The elastic ring (8) of the rear hub (1) of the invention comprises a circular flat body with two free ends (8a, 8b) so as to be able to expand towards the inner surface (2c) of the body (2)
Data Source
Figure 1~1A
Figure 2
Figure 3
AI summary
The invention refers to the internal connection of a rear bicycle wheel hub (1) comprising a cylindrical body (2) that surrounds an axle (3), where a proximal end (2b) of the body (2) is attached to a freehub body (4) that surrounds a freewheel system (6). A connecting mechanism (5) between the body (2) and the freewheel system (6) of the freehub body (4) is characterized in that it comprises a connecting crown (7) coupled to an inner surface (2c) of the body (2) that connects with a ring (6a) in the freewheel system (6) and an elastic ring (8) seated in a circular recess (9) on a lateral surface (7c) of the connecting crown (7) so that it can expand towards the inner surface (2c) of the body (2) and fix the connecting crown (7) inside the body (2).