Split Pinion Face Gear Shifting for Low-Wear Gear Changes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional gear shifting systems, such as those used in bicycle shaft drive systems, face inefficiencies and component wear due to friction and the need for additional shifting force during gear changes, especially when pedaling, and lack a mechanism for smooth gear shifting without loss of momentum or power.
Innovation Solution
A pinion gear assembly with split sections that can align with two gear rings simultaneously, allowing for smooth and efficient gear shifting by splitting and re-aligning during rotation, reducing friction and wear, and enabling gear changes without additional pedaling energy or loss of power.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single gear-pinion is used to enable gear change, then the device complexity is reduced, but additional shifting force is required to overcome friction between pinion teeth and gear ring teeth during lateral sliding
Solution Approach 1:
The pinion gear is divided into two separate pinions (first pinion and second pinion) that can independently engage with different gear rings. This segmentation allows each pinion to be optimally positioned for its specific gear ring, reducing lateral sliding friction and the force required for shifting while maintaining overall system simplicity
2Ease of operation
If multiple gear-pinions are used to allow shift between concentric gear rings, then the gear shifting smoothness is improved, but the device complexity and number of components increases
Solution Approach 1:
The first and second pinions are designed with universal engagement capabilities, where each pinion can engage with multiple gear rings depending on its axial position. This multi-functionality allows two pinions to handle shifts between three gear rings, reducing the total number of pinions needed while maintaining smooth shifting operation
3Device complexity
If the pinion teeth slide laterally across gear ring teeth during gear change, then the gear shifting mechanism is simplified, but excessive wear of the teeth occurs
Solution Approach 1:
The pinions are designed to dynamically adjust their axial positions along the drive shaft, allowing them to engage and disengage from different gear rings smoothly. This dynamic positioning reduces lateral sliding by enabling more gradual engagement transitions, thereby reducing tooth wear while maintaining mechanism simplicity
Data Source
Figure 1
Figure 2a~2b
Figure 3a~3c
AI summary
The present invention relates to a gear shifting system comprising a drive shaft (8), a face gear (7), and at least one power transmission component(s). The gear system comprising also a pinion gear assembly (13), which is coupled to the first end of the drive shaft (8). The pinion gear assembly (13) is configured to mesh with one of the concentric gear-rings on the face gear (7), so that the rotational movement of the gear-ring is transmitted to the shaft. The gear shifting system is easy to operate, mechanically simple, can smoothly shift between gears under any gear shifting conditions, and exhibits decreased component wear.