| 摘要 |
Automatic continuously adjustable bicycle drives are already known. Their design and construction are however considerably costly, in particular to achieve fine adjustment steps with a Bowden wire lever and a transmission device. In order to reduce construction costs and to improve the efficiency of the drive, the chain wheel (2) connected to the hub (3) of the rear wheel consists of several tooth segments (6), i.e. of at least three tooth segments whose outer circumference provided with teeth (7) is an involute. The tooth segments are swivellingly received against the force of a restoring spring (8) in a housing (10) preferably mounted on the free-wheel (9) of the hub (3). This bicycle drive may be used in all bicycles, even bicycles with particularly high cross-country mobility requirements. |
