Bicycle Shifter Single Lever Cable Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional bicycle shifters with separate control levers for pulling and releasing the control cable result in added weight and discomfort due to the need to repeatedly maneuver hands and fingers between levers, while single-lever designs operable in two directions can lead to discomfort and loss of control during gear shifting.
Innovation Solution
A bicycle shifter with a single control member that can move in a single direction to both pull and release the control cable, utilizing a housing with a takeup member biased for cable-release, a ratchet wheel with uneven teeth, and a drive mechanism that disengages the holding pawl to allow gear shifts, providing both audible and tactile feedback.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate control levers are used for pulling and releasing the control cable, then the gear shifting function is reliable, but the device weight increases and operation comfort deteriorates
Solution Approach 1:
The patent combines two separate control levers (one for pulling the cable, one for releasing it) into a single control lever that can perform both functions by moving in opposite directions. This merging reduces the number of components, decreases weight, and simplifies the overall shifter structure while maintaining the reliable gear shifting function through the bidirectional operation capability.
Solution Approach 2:
The single control lever is designed to serve multiple functions: it can pull the control cable in one direction and release it in the opposite direction. This multi-functionality eliminates the need for separate dedicated levers for each operation, reducing device complexity and weight while preserving operational reliability.
2Reliability
If separate control levers are used for pulling and releasing the control cable, then the gear shifting function is reliable, but the ease of operation deteriorates due to repeated hand movements
Solution Approach 1:
By merging the pull and release functions into a single control lever, the rider no longer needs to move their hand between separate levers. The unified lever allows both operations from a single location, significantly improving ease of operation and reducing repetitive hand movements while maintaining gear shifting reliability.
Solution Approach 2:
The control lever's ability to perform both pulling and releasing functions universally from one position eliminates the need for repeated hand repositioning. This multi-functional design keeps the rider's hand in one place, enhancing operational comfort and ease of use.
3Device complexity
If a single lever operable in two directions is used, then the device complexity is reduced, but operation comfort deteriorates due to hand maneuvering between lever sides
Solution Approach 1:
The control lever is segmented into distinct functional zones or sections along its length, with each side or portion dedicated to a specific function (pulling vs. releasing). This segmentation allows the rider to operate different functions at different locations along the same lever body, eliminating the need to maneuver the hand between separate levers while maintaining reduced device complexity.
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 efficient and comfortable gear shifting with reduced weight and improved control, allowing single or multiple gear changes in either direction with a single lever movement, enhancing the overall riding experience.
Implementation Method 1
the takeup member is biased in the cable-release direction by tension in the control cable
Implementation Method 2
The control member is biased toward a rest position
Implementation Method 3
a ratchet wheel having preferably a plurality of unevenly spaced teeth about its periphery, the ratchet wheel being rotatable with the takeup member, while the holding mechanism includes a holding pawl engageable with the ratchet wheel teeth to retain the takeup member in a selected gear position
Data Source
AI summary
A bicycle shifter for pulling and releasing a control cable connected to a gear change mechanism that includes a housing mountable to a handlebar, a takeup member, a control member, a holding mechanism and a release mechanism. The takeup member is movable for pulling the control cable in a cable-pull direction and releasing the control cable in a cable-release direction. The control member is movable in a shift direction from a rest position for a first shift movement to permit motion of the takeup member in the cable-release direction. The first shift movement corresponds to a single gear change. The control member is movable in the shift direction from the rest position for a second shift movement to move the takeup member in the cable-pull direction. The second shift movement corresponds to a plurality of gear changes. The second shift movement is greater than the first shift movement. The control member is biased toward the rest position. The holding mechanism retains the takeup element in a selected gear position. The drive mechanism is operable for releasing the holding mechanism from the takeup member and for moving the takeup member in response to actuation of the control member.