Combined drive for bicycle dynamo and tachometer

摘要

Bicycle dynamos usually have a fluted friction wheel which is pressed against the rotating side wall of the bicycle tyre during use of the dynamo. As is known, such drives have an unfavourable efficiency and are unreliable, in particular in bad weather and in the event of a diminishing contact force of the dynamo, so that satisfactory illumination is no longer available. The novel combined drive is intended to increase the road safety and allow energy-saving dynamo operation as a result of a high availability of illumination and a noticeable annular lateral reflection surface. A novel toothed ring 6 is attached to the wheel spokes 3, in the toothing 2 of which toothed ring 6 the pinion 1 which is fastened on the dynamo shaft 7 in place of a friction wheel engages in a positive-locking and frictionally engaged manner. Uniform tooth engagement between the pinion 1 and the toothing 2 is achieved by means of a roller 5 which is arranged concentrically on the pinion 1 and runs along the non-toothed part of the toothed ring 6. Slipless drive for bicycle dynamos which, at the same time, can also be used as a drive for tachometers. <IMAGE>