Coaxial double-input gearbox structure

The utility model provides a coaxial double-input gearbox structure which enables two power sources and a transmission to be connected conveniently and reliably, enables the size of a gearbox to be small, and ensures that power output is not interrupted. The transmission mechanism comprises a double-input shaft and a power output shaft which are coaxially arranged, the double input shafts comprisea second hollow input shaft and a first input shaft; the first input shaft penetrates through a hollow inner cavity of the second hollow input shaft and is coaxially arranged; the input end of the second hollow input shaft is connected with an external second power source; the input end of the first input shaft is connected with an external first power source; the output end of the second hollowinput shaft is fixedly sleeved with a second transmission gear; the output end of the first input shaft is arranged behind the second transmission gear and sequentially sleeved with a coupling synchronizer and output six-gear