Multi-gear self-adaptive gear box for railway vehicle

The invention provides a multi-gear self-adaptive gear box for a railway vehicle. The gear box comprises a gear box body, an input pinion shaft, an intermediate gear shaft and a power output shaft, the input pinion shaft is arranged on the gear box body through N input gears, the intermediate gear shaft is arranged on the gear box body through M intermediate gears, and K of the M intermediate gears are engaged with gears on the power output shaft, wherein N>=2, and M=N +K; and the gear box further comprises a gear shifting driving part, the gear shifting driving part comprises a driving source, and the driving source is controlled to rotate forwards and backwards to left and right displace the M-K gears on the intermediate gear shaft to be respectively engaged with the N input pinion shafts. Compared with the related art, the gear box provided by the invention changes the load point of a vehicle driving system, so that a motor and a converter operate in an optimal efficiency range, andthe self-adaptive perfor