Single Lever Bicycle Control Device for Brake and Derailleur
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bicycle control devices require cyclists to move their hands to switch between braking and gear shifting operations, leading to potential loss of grip and reduced stability.
Innovation Solution
A single lever control device that allows simultaneous or sequential operation of braking and gear shifting without hand movement, featuring a support body with a single mobile lever that can command both brake and derailleur in two opposite directions, with distinct movements for upward and downward gear shifting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If multiple separate levers are used for brake and gear shifting operations, then each function can be controlled independently, but the cyclist must move their hand to switch between operations, leading to potential loss of grip and reduced stability
Solution Approach 1:
The patent combines multiple control functions (brake and gear shifting) into a single integrated lever. The lever can be actuated in different directions: pulling towards the handlebars activates the brake, while pushing forward activates gear shifting. This merging eliminates the need to move the hand between separate controls, maintaining continuous grip on the handlebar while enabling multiple operations.
Solution Approach 2:
The single lever is designed to perform multiple functions through different actuation directions. The same lever component can command both the brake cable and the derailleur cable, making it a universal control element. This multi-functionality reduces the number of separate control devices while maintaining independent control over braking and gear shifting operations.
2Reliability
If a single lever is used for both brake and gear shifting operations, then hand movement is eliminated improving stability, but the device complexity increases due to the need for a single lever to command multiple functions
Solution Approach 1:
The lever is designed with dynamic actuation capabilities, allowing it to be moved in different directions (pulling back for brake, pushing forward for gear shift). This dynamic design enables a single static component to control multiple functions through varied motion, reducing the need for multiple separate levers while maintaining reliability through continuous hand contact.
Solution Approach 2:
The patent introduces an intermediate body that serves as a mediator between the single lever and the multiple control functions. The intermediate body receives actuation from the lever in different directions and accordingly commands either the brake cable or the derailleur cable. This intermediary mechanism allows one lever to control multiple functions without requiring complex direct linkages.
3Ease of operation
If distinct movements are required for upward and downward gear shifting, then precise gear control is achieved, but the control mechanism becomes more complex
Solution Approach 1:
The indexing mechanism is segmented into distinct components: a gear wheel with multiple spaces, ratchets for directional control, and an intermediate body. Each space on the gear wheel corresponds to a specific gear position, and the ratchets control movement in opposite directions. This segmentation allows precise gear selection through distinct lever movements while organizing the complexity into manageable, functional modules.
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
Enables quicker and safer cycling by allowing braking and gear shifting without hand movement, improving riding conditions by preventing unintended gear shifts during braking and vice versa.
Implementation Method 1
the elastic return action of an elastic return member (typically a spring) provided in the derailleur itself
Implementation Method 2
the control cable is actuated in traction or in release through winding and unwinding on a rotor element, commonly known as cable-winding bush, the rotation of which is controlled by the cyclist with suitable control levers
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Integrated control device for a bicycle, comprising a support body suitable for being fixed to the handlebars of a bicycle and a single lever that is mobile with respect to the support body to command both a brake and a derailleur in two first and second directions of movement, opposite one another; the single lever has a rest position in which it commands neither the brake nor the derailleur and it is mobile in a first direction to command the brake; the single lever is mobile in a second direction different from the first direction by a first amount for the movement of the derailleur in its first direction and by a second amount different from the first amount for the movement of the derailleur in its second direction.