US Patent 9085340 Electronic front derailleur

The present invention provides an electronic front derailleur including a driving member, a driving pulley, a driven pulley, a transmission shaft, a transmission assembly, and a chain guide member disposed with a chain-moving member connected to the transmission assembly, wherein the chain-moving member is disposed with a groove to receive a chain. When the driving member drives the driving pulley to rotate the driven pulley, then the driven pulley further actuates the transmission shaft to move therewith, and then the transmission assembly and the chin guide member are further driven to make movements, allowing the bicycle chain move from one sprocket to another sprocket with a different size.