Bicycle Multi-Sprocket Locking Screw for Wider Gear Range
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional bicycle derailleur systems face limitations in achieving a wide range of transmission ratios due to the standardized installation width and geometry of the driver, which restricts the use of smaller sprockets, particularly those with ten or fewer teeth, as they are incompatible with standard components and more costly specialized drivers.
Innovation Solution
A multi-sprocket assembly with a locking screw arrangement that allows at least two smallest sprockets to be axially fixed to the driver, featuring a shaft portion with an external thread that engages with the driver's internal thread, enabling a larger transmission ratio without requiring specialized drivers, by using a locking screw arrangement with an external thread diameter larger than the shaft portion, allowing for more sprockets and improved gear range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If specialized drivers are used to accommodate smaller sprockets, then the transmission ratio range is improved, but costs increase due to non-standard components
Solution Approach 1:
The locking screw arrangement is designed to be compatible with standard drivers, allowing the same locking screw design to be used across different driver models. This universal design approach enables the system to accommodate various sprocket sizes without requiring specialized drivers for each application, thereby reducing manufacturing costs.
Solution Approach 2:
The driver system is segmented into two independent components: the standard driver and the locking screw arrangement. This segmentation allows the locking screw to be optimized for accommodating smaller sprockets while the driver remains a standard, cost-effective component, avoiding the need to redesign the entire driver assembly.
2Quantity of substance
If more sprockets are added to increase the number of gears, then the transmission ratio range is improved, but the installation width constraint is exceeded
Solution Approach 1:
By mounting sprockets on the axially extending locking screw rather than on the driver's outer circumference, the patent utilizes the axial dimension to accommodate additional sprockets. This vertical arrangement allows more sprockets to be fitted within the same radial space, effectively increasing the number of gears without exceeding the installation width constraint.
Data Source
AI summary
A multi-sprocket assembly for a bicycle rear wheel assembly comprising a multi-sprocket arrangement and a locking screw arrangement. The multi-sprocket arrangement is configured to be couplable to a driver of the wheel assembly in a torque-transmitting manner and comprises at least eleven sprockets. The multi-sprocket assembly is configured such that at least two of the smallest sprockets are axially fixed to the driver via the locking screw arrangement. The locking screw arrangement has a shaft portion for receiving at least one sprocket. The shaft portion has an axially outer stop portion at one end region and at least one external thread at an opposite end region. The external thread configured to be screwed into an associated internal thread to fix the locking screw arrangement. The external thread has an outer diameter which is larger than an outer diameter of a shaft portion region that receives the at least one sprocket.