Bicycle Derailleur Friction Element Chain Tension
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bicycle derailleurs face issues with chain derailment and slack management, particularly when riding over rough terrain, due to insufficient rotational resistance, leading to increased risk of chain derailment or entanglement between sprockets.
Innovation Solution
A bicycle derailleur system incorporating a friction element between a movable member and a chain guide to provide rotational resistance, coupled with a motor to adjust the chain guide's position, ensuring consistent tension and reducing the risk of derailment by applying controlled resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If rotational resistance is increased to prevent chain derailment, then chain guide stability improves, but the mechanism complexity increases
Solution Approach 1:
The electromagnetic brake serves multiple functions: it provides motion damping to prevent chain derailment, maintains chain tension during gear changes, and can be controlled through existing derailleur actuation mechanisms. This multi-functionality reduces the need for separate dedicated components for each function.
Solution Approach 2:
The electromagnetic brake acts as an intermediary between the chain guide's rotational movement and the control system. It translates small control signals into appropriate braking forces, providing a bridge between the rider's inputs and the chain guide's response while isolating the complexity within a single controllable component.
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 system effectively maintains chain tension and prevents derailment by providing adjustable rotational resistance, enhancing the reliability and safety of gear shifting, especially on rough terrain.
Implementation Method 1
a friction element is operatively arranged between a movable member and a chain guide to frictionally provide rotational resistance in a first rotational direction of the chain guide
Data Source
AI summary
A bicycle derailleur basically includes a base member, a movable member, a chain guide, a friction element and a motor. The base member is configured to be mounted to a bicycle. The movable member is movably coupled to the base member. The chain guide is coupled to the movable member to rotate around a rotational axis with respect to the movable member. The friction element is operatively arranged between the movable member and the chain guide to frictionally provide rotational resistance in a first rotational direction of the chain guide. The motor is operatively coupled to the movable member to move the movable member with respect to the base member.