Variable speed drive for a bicycle
US5342075A · kind A · utility
Inventor
Key dates
| Filing date | Nov 23, 1992 |
| Grant date | Aug 30, 1994 |
| Priority date | — |
| Expiry date | Nov 23, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/1933
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
This invention relates to bicycles, specifically to an improved speed changing mechanism for a bicycle. The primary attribute of this invention is the utilization of a pair of pinion shafts and a pair of face gears to accomplish variation in speed. The face gear teeth and pinion are designed so that only one pair of teeth mesh at a time so that effectively they run as a pair of spur gears. The pinion shafts both forward and aft float inside a telescopic sleeve which allows a large number of gear ratios to be installed on the bicycle. The telescopic sleeve functions as a drive shaft connecting the output of the crank to a follower. The cyclist can select a gear ratio at the crank end by positioning the forward pinion. The aft pinion is positioned by a cable plus a cable lever. The invention eliminates the chain and provides a constant speed ratio at the crank. The telescopic sleeve eliminates the tension in the chain and will increase bearing life. The invention does not require major modifications to the bicycle because the free wheel mechanism and crank are not disturbed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.