| 摘要 |
In a chain shifting device for a bicycle or the like, a bicycle chain extending from the pedal crank can be shifted between the wheels of a chain wheel set positioned on a driven wheel. The chain is trained over the guide wheel and tensioning wheel of a chain guiding and tensioning member. A system of parts guides the chain guiding and tensioning mechanism between its different positions. The system of parts includes a movable joint block connected to the chain guiding and tensioning mechanism and a fixed joint block connected to the bicycle frame. An articulated lever and a guide member are connected by different joints to the movable and fixed joint blocks and are joined together by still another joint. A locking mechanism interlocks two of the parts of the system which are movable relative to one another for securing at least one position of the chain guiding and tensioning mechanism. |
