Bar-End Bicycle Gearshift Lever with Nested Pressure Areas
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Bicycle gearshift actuation devices for speed races face challenges in maintaining aerodynamic efficiency and ease of use, as cyclists need to change hand positions significantly to operate controls, disrupting their aerodynamic stance and increasing effort during races.
Innovation Solution
The design of a control lever with multiple concave and flat pressure areas allows the cyclist to maintain an aerodynamic hand position while shifting gears, with thumb and index finger positions optimized to reduce movement and enhance control, featuring asymmetric mounting and tapered arm shapes for improved aerodynamics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If traditional bar-end gearshift devices are used, then gearshifting can be actuated, but the cyclist must change hand position significantly, disrupting aerodynamic posture
Solution Approach 1:
The control lever is designed with nested pressure areas where the first upper pressure area is adjacent to and nested with the body, the third lower pressure area is nested between the body and second pressure area, allowing multiple finger positions to be accommodated within the compact lever structure, enabling gearshifting without hand position changes
Solution Approach 2:
The control lever arm projects substantially tangentially to the upper part of the body in a direction perpendicular to the main axis, creating a lateral dimension for finger engagement that allows aerodynamic hand positioning while maintaining operational accessibility
2Productivity
If hand position is changed to operate traditional gearshift devices, then gearshifting can be performed, but cyclist effort increases and cramping risk rises
Solution Approach 1:
The control lever is pre-configured with multiple pressure areas (first upper, third lower, and second lower) positioned to accommodate thumb and index finger in aerodynamic positions before gearshifting begins, allowing immediate operation without preliminary hand repositioning movements that consume energy
3Object-affected harmful factors
If control lever allows multiple finger positions, then aerodynamic posture is maintained, but device complexity increases
Solution Approach 1:
The control lever arm is segmented into distinct pressure areas (first upper pressure area adjacent to body, third lower pressure area between body and second pressure area, and second lower pressure area) each serving specific finger engagement functions, allowing multiple aerodynamic positions within a single unified component rather than multiple separate controls
Data Source
AI summary
The control lever (120) comprises a substantially cylindrical body (130) for mounting in the actuation device (100) and an arm (140), which projects with respect to the body (130) according to a main axis (A) substantially tangential to the upper part of the body (130) and is intended to face forwards in the direction of travel of the bicycle. The arm (140) comprises a first upper pressure area (141), concave and adjacent to the body (130), and a second lower pressure area (142), remote from the body (130).