Sage Leaf Bicycle Frame Profile Reduces Drag
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bicycle designs fail to effectively minimize drag and harness wind energy for enhanced performance, particularly in conditions with varying wind angles, leading to increased cyclist effort and battery consumption in electrically assisted bicycles.
Innovation Solution
Implementing a symmetrical aerodynamic profile with a sage leaf shape defined by 5 tangent arcs of circles, which generates a motor effect in the direction of forward movement across varying wind conditions, reducing drag and enhancing propulsion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional bicycle frame profiles are used, then manufacturing is simpler, but drag is not minimized and no motor effect is generated
Solution Approach 1:
The patent applies curved surfaces by defining the frame profile using 5 tangent arcs of circles instead of straight lines or simple curves. This complex curvature arrangement creates the sage leaf shape that generates the motor effect and minimizes drag by optimizing airflow around the frame tubes.
Solution Approach 2:
The patent changes the geometric parameters of the frame profile by specifying exact ratios (E/C between 0.1-0.3) and using 5 specific circular arcs with defined radii and tangency points. This precise parameter control transforms the conventional simple profile into the optimized sage leaf shape that produces aerodynamic benefits.
2Productivity
If conventional frame profiles are used, then structural strength is maintained, but aerodynamic performance is suboptimal
Solution Approach 1:
The patent modifies the frame's geometric parameters by implementing the sage leaf profile with specific E/C ratios (0.1-0.3) and 5 tangent circular arcs. This transforms the frame from a conventional shape to one that generates a motor effect and reduces drag, directly improving aerodynamic performance while maintaining structural integrity through the distributed curvature.
Solution Approach 2:
By replacing conventional straight or simple curved tube profiles with the complex 5-arc tangent circle configuration, the patent creates a frame that actively interacts with airflow to generate propulsive force, significantly enhancing aerodynamic performance.
3Loss of energy
If the sage leaf profile with 5 tangent arcs is implemented, then drag is reduced and motor effect is generated, but manufacturing precision requirements increase
Solution Approach 1:
The patent defines the complex sage leaf profile using 5 tangent arcs of circles with specific radius ratios and tangency conditions. This mathematical definition provides a precise manufacturing blueprint that achieves the aerodynamic motor effect while allowing for controlled fabrication through defined geometric constraints.
4Weight of moving object
If minimal frame weight is pursued, then weight reduction is achieved, but aerodynamic optimization is compromised
Solution Approach 1:
The patent implements the sage leaf profile with its 5 tangent circular arcs to create an aerodynamically optimized frame shape. This curvature-based design generates a motor effect that produces propulsive force, counteracting the weight reduction by providing active aerodynamic assistance that reduces overall energy consumption.
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 sage leaf profile reduces drag and generates a motor effect, saving battery power and reducing cyclist effort by up to 40%, allowing for longer battery life and improved performance in electrically assisted bicycles.
Implementation Method 1
the applicant, following research and numerous tests, found that by using completely specific profiles in the shape of a sage leaf with 5 tangent arcs of circles, it was possible to reduce, or even completely cancel the drag, but also in the case of a side or inclined wind, to generate a positive force in the direction of forward movement of the bicycle
Implementation Method 2
by using completely specific profiles in the shape of a sage leaf with 5 tangent arcs of circles, it was possible to reduce, or even completely cancel the drag
Data Source
Figure 1
Figure 2~4C
Figure 5~6
AI summary
The invention relates to an aerodynamic symmetric profiled element (1) for a wheeled vehicle (V) having, in cross section perpendicular to the plane of symmetry (12), at least 90% of the central part of a profiled section with at least 5 circular arcs, referred to as a sage-leaf shape, with a ratio of the maximum width (E) measured perpendicularly to the plane of symmetry (12)/chord (C) measured in the plane of symmetry (12) of between 0.1 and 0.3. Said profiled section is designed to create a force that is always oriented towards the leading edge (16) of the profiled section for all the resultants combining the wind speed and the speed of forward movement of the vehicle.