Eight-gear double-input gearbox

According to the eight-gear double-input gearbox, eight-gear output is completed through seven pairs of gears, the axial length of the gearbox is reduced, and the application requirement of a vehicle body is met. The long input shaft penetrates through a center receding hole of the short input shaft to protrude backwards and is arranged towards the output shaft, the output shaft and the long input shaft are coaxially arranged, the front end of the output shaft is sleeved with a direct gear synchronizer, and a second-fourth gear, a fifth-seventh gear, an output shaft synchronizer and a first-third gear are sequentially arranged behind the direct gear synchronizer of the output shaft. A coupling synchronizer, a long input shaft low-gear gear, a long input shaft synchronizer and a long input shaft high-gear gear are sequentially arranged on the rear convex part of the long input shaft; a short input shaft high-gear gear, a short input shaft synchronizer and a short input shaft low-gear gear are sequentially arra