Chain drive means for a bicycle or the like
US4181034A · kind A · utility
Inventor
Key dates
| Filing date | Apr 27, 1978 |
| Grant date | Jan 1, 1980 |
| Priority date | — |
| Expiry date | Apr 27, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/2165
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A drive mechanism is disclosed for driving the chain of a bicycle, motorbike or the like, including a sprocket gear adapted for rotatable connection at its center with the vehicle frame, the sprocket gear periphery including a pair of diametrically opposed portions of corresponding cycloid configuration, and a pair of foot pedal crank arms connected with, and extending diametrically outwardly from the center of, the sprocket gear, the crank arms being angularly advanced, relative to the minor axis of the sprocket gear, in the power supplying direction of rotation by an angle of from about 30.degree. to about 40.degree.. In one modification, the cycloid portions are spaced in the direction of the minor axis of the sprocket gear, the adjacent ends of the cycloid surfaces being joined by tangentially arranged arcs of a circle the diameter of which equals the length of the major axis of the cycloid. In order to provide change speed gearing capability, a second corresponding sprocket gear of different size may be connected adjacent and coaxially with the first sprocket gear.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.