摘要 |
Device for use in bicycles having displaceable chain sprocket segments as variable-speed gear change. The gear change must be able to be made during travel, i.e. the segments are displaced whilst the chain sprocket and the chain are going round. This requirement has been met through the use of diverters (α,β). Whenever there is a change of gear, the angled diverters are placed transversely across and in the way of the circling segments. Following the collision, three functions occur in quick succession; the fixation of the segment loosens, the segment is displaced and the segment is re-fixed elsewhere, this in rotation, and an altered chain sprocket diameter has come about. This is effected with light touch and over a short time. Afterwards no solid connection whatever exists between segments and diverters. The driving and the driven chain sprocket lie always with all gear changes in the same plane, which means the avoidance of edge wear on the chain parts. The chain does not pull obliquely. The efficiency level is favourable since no sliding friction arises, for example planetary gearing. <IMAGE> |