Bicycle Rear Sprocket Weight Reduction via Segmented Support

The sprocket support member is divided into multiple discrete support members (first support member, second support member, etc.) that are positioned radially around the rotational axis. Each support member is a separate component that can be independently optimized, allowing weight reduction through selective material placement while maintaining overall structural strength through the distributed arrangement.

Each support member features varying thickness profiles with radially outer portions that are thicker than radially inner portions. This local quality variation optimizes material distribution - thicker sections provide strength where loads are applied (at the outer radius where sprocket teeth engage), while thinner sections reduce weight in areas experiencing lower stresses.

The support members serve multiple functions simultaneously: they provide structural support, define the axial gap for sprocket positioning, and create attachment surfaces for joining methods. The axial gap between support members serves both as a positioning feature for the sprocket and as a weight-reduction feature, eliminating material that would otherwise be needed for solid continuous structure.

The invention transitions from considering only radial spacing between support members to utilizing the axial dimension by creating an axial gap. This axial separation allows the sprocket to be positioned between support members, providing structural integrity through the radial arrangement while reducing weight through axial spacing. The attachment portions extend radially outward to bridge this axial gap, maintaining integrity without requiring continuous material.

The attachment portions are designed as distinct features on each support member rather than being integrally formed with the entire support structure. This segmentation allows each support member with its attachment portion to be manufactured separately using optimized processes, then joined together. The attachment portions can be specifically designed for diffusion bonding or other joining methods, enabling weight reduction through precise material placement only where needed for attachment.

The support members and attachment portions can be manufactured from different materials or material treatments optimized for their specific functions. The support member body can use materials optimized for structural strength, while attachment portions can use materials or surface treatments optimized for bonding. This composite approach enables weight reduction by selecting materials based on local requirements rather than using a single heavy material throughout.